Reducing Adverse Drug Events in Old Age

Reducing Adverse Drug Events in Old Age Introduction

Drug interactions in older adults are a significant concern in geriatric nursing, as they can lead to adverse drug events (ADEs) that affect health outcomes and quality of life. Older adults often take multiple medications, both prescribed and over-the-counter (OTC), increasing their risk of ADEs due to drug interactions. These events can lead to severe health complications, including falls, fractures, cognitive decline, hospitalization, and even death. Understanding the causes of drug interactions, recognizing high-risk medications, and implementing effective nursing interventions and strategies are critical to minimizing these risks and improving patient safety.

Adverse Drug Events in Older Adults

An adverse drug event (ADE) is any harm experienced by a patient due to medication use, which may result from the normal use of a drug, inappropriate use, suboptimal prescribing, poor adherence, self-medication, or medication errors. In older adults, ADEs are alarmingly common, with nearly 1.9 million ADEs occurring annually among Medicare beneficiaries. Of these, approximately 180,000 are life-threatening or fatal (Gurwitz et al., 2003). Factors contributing to the high incidence of ADEs in older adults include altered pharmacokinetics and pharmacodynamics, polypharmacy, incorrect dosing, self-medication, iatrogenic causes, medication adherence issues, and medication errors.

Causes of Adverse Drug Events

Several factors contribute to the increased susceptibility of older adults to ADEs:

1. Alterations in Pharmacokinetics and Pharmacodynamics: Aging affects drug absorption, distribution, metabolism, and excretion. Reduced renal and hepatic function, decreased gastrointestinal motility, and changes in body composition can alter how drugs are processed in the body, leading to a higher risk of toxicity or inadequate therapeutic response (Mangoni & Jackson, 2004; Rochon, 2010).
2. Polypharmacy: Many older adults take multiple medications to manage chronic conditions, increasing the likelihood of drug-drug and drug-disease interactions. Polypharmacy is associated with an elevated risk of ADEs, especially when combined with other factors like cognitive impairment or frailty (Gallagher, Barry, & O’Mahony, 2007).
3. Incorrect Doses of Medications: Incorrect dosing, whether too much or too little, is a common cause of ADEs in older adults. Age-related changes in drug metabolism and clearance make it challenging to determine the correct dosage, leading to potential overdoses or underdoses (Hanlon et al., 2001).
4. Self-Medication or Prescribing Cascades: Older adults may self-medicate with OTC drugs or supplements, unaware of potential interactions with their prescription medications. Additionally, healthcare providers may prescribe medications to treat side effects caused by other drugs, leading to a “prescribing cascade” (Rochon & Gurwitz, 1997).
5. Iatrogenic Causes: Iatrogenic ADEs result from medical interventions, including inappropriate prescribing, medication errors, and adverse drug reactions (ADRs). Frail older adults with multiple medical problems and numerous prescribed and non-prescribed medications are at high risk for iatrogenic ADEs (Rochon, 2010).
6. Medication Adherence Issues: Nonadherence to medication regimens is a common issue among older adults, often due to complex dosing schedules, cost, side effects, or cognitive impairment. This nonadherence can result in inadequate therapeutic outcomes or increased risk of ADEs (Steinman & Hanlon, 2010).
7. Medication Errors: Errors in prescribing, dispensing, or administering medications can lead to significant ADEs. Common errors include administering the wrong medication, incorrect dosing, or inappropriate timing (Kohn et al., 2000).

Adverse Drug Reactions

An adverse drug reaction (ADR) is a type of ADE characterized by any toxic or unintended response to a medication. ADRs account for a significant proportion of ADEs in older adults, with hospital admissions due to ADRs reported to range from 5% to 35% (Gurwitz et al., 2003). In community-dwelling older adults, approximately 38% of ADRs are considered serious, life-threatening, or fatal, and 27% are deemed preventable (Gurwitz et al., 2005).

Drug-Drug and Drug-Disease Interactions

Drug-drug interactions occur when one medication alters the concentration or biological effect of another, leading to increased toxicity or reduced efficacy. Drug-disease interactions happen when a medication adversely affects an existing medical condition. Older adults, often managing multiple chronic conditions, are at high risk for these interactions due to polypharmacy and the involvement of multiple healthcare providers (Gray & Gardner, 2009).

Medication Errors

Medication errors are a significant contributor to ADEs in older adults. These errors can occur at any stage of the medication process, including prescribing, dispensing, administration, and monitoring. The Institute of Medicine (IOM) reported that nearly 7,000 hospital deaths were associated with medication errors in 1999 (Kohn et al., 2000). Common types of medication errors include administering the wrong medication, incorrect dosing, or inappropriate timing.

To reduce medication errors, healthcare organizations should implement strategies such as computerized physician order entry (CPOE) systems, medication reconciliation processes, and comprehensive education programs for healthcare providers and patients.

High-Risk Medications in Older Adults

Certain medications pose a higher risk of ADEs in older adults due to their side effects, potential for drug interactions, and the increased sensitivity of older patients to these drugs. These high-risk medications include:

1. Anticholinergics: These drugs, commonly used to treat conditions such as urinary incontinence and allergies, can cause confusion, dry mouth, constipation, urinary retention, and blurred vision in older adults.
2. Benzodiazepines: Often prescribed for anxiety or insomnia, benzodiazepines can increase the risk of falls, cognitive impairment, and sedation.
3. Non-Steroidal Anti-Inflammatory Drugs (NSAIDs): NSAIDs, frequently used for pain management, can lead to gastrointestinal bleeding, kidney damage, and cardiovascular events in older adults.
4. Opioids: While effective for pain management, opioids carry a high risk of respiratory depression, falls, and constipation.
5. Antipsychotics: Used to manage behavioral symptoms in dementia, antipsychotics can increase the risk of falls, cognitive decline, and cardiovascular events.
6. Anticoagulants: Medications like warfarin and newer oral anticoagulants pose a significant bleeding risk, particularly in older adults with comorbidities or those taking multiple medications.

Over-the-Counter (OTC) Medications and Herbal Supplements

Many older adults use OTC medications and herbal supplements, often without informing their healthcare providers. This practice can lead to unrecognized drug-drug or drug-disease interactions. Common OTC medications that pose risks for older adults include:

• Aspirin and NSAIDs: These can cause gastrointestinal bleeding and kidney damage, especially when taken with other medications.
• Antacids: Some antacids may interfere with the absorption of other medications, reducing their effectiveness.
• Laxatives: Overuse of laxatives can lead to electrolyte imbalances and dehydration.
• Herbal Supplements: Supplements such as St. John’s Wort, Ginkgo Biloba, and Ginseng can interact with prescription medications, affecting their efficacy or increasing the risk of side effects.

Nursing Interventions and Strategies

Nurses play a critical role in preventing and managing ADEs in older adults. Effective nursing interventions and strategies include:

1. Medication Reconciliation: Nurses should conduct thorough medication reconciliation during patient admission, transfer, and discharge to identify potential drug-drug or drug-disease interactions, duplications, and omissions. This process involves reviewing all prescription medications, OTC drugs, herbal supplements, and vitamins that the patient is taking.
2. Assessment of Medication Knowledge and Adherence: Nurses should assess the patient’s understanding of their medications, including the purpose, dosing, potential side effects, and interactions. Educating patients and caregivers about the importance of adherence and the risks of nonadherence is essential to improving outcomes.
3. Use of Assessment Tools: Several tools can help nurses identify potential drug interactions and inappropriate medication use:
   • Beers Criteria: A list of potentially inappropriate medications for older adults.
   • STOPP/START Criteria: Tools to identify potentially inappropriate medications (STOPP) and suggest appropriate ones (START).
   • Drug Interaction Checkers: Computerized tools or mobile applications to identify potential drug-drug and drug-disease interactions.
4. Monitoring for Signs of ADEs: Nurses should regularly monitor for signs and symptoms of ADEs, such as confusion, dizziness, falls, changes in mental status, gastrointestinal disturbances, or any unexplained symptoms. Early identification of ADEs can prevent further complications.
5. Promoting Safe Medication Practices: Encourage older adults to use a single pharmacy to fill their prescriptions, which allows the pharmacist to monitor for potential drug interactions. Encourage the use of medication organizers or blister packs to simplify complex regimens.
6. Encouraging Reporting of Side Effects: Encourage patients to report any new or unusual symptoms they experience, as these may be signs of a potential ADE. Nurses should facilitate open communication and create a non-judgmental environment for patients to discuss their medication concerns.
7. Interdisciplinary Collaboration: Collaborate with other healthcare professionals, such as pharmacists, physicians, and dietitians, to review medication regimens, identify potential interactions, and adjust therapies as needed. Interdisciplinary rounds and consultations can help ensure that medication management is comprehensive and patient-centered.
8. Educating Patients and Caregivers: Provide education on the importance of medication adherence, potential side effects, and the risks associated with polypharmacy and OTC drug use. Tailor education to the patient’s literacy level and cognitive status, using clear language, visual aids, and teach-back techniques.
9. Adjusting Medication Regimens: Work with healthcare providers to adjust medication regimens based on the patient’s age, renal and hepatic function, and overall health status. Use the lowest effective dose and minimize the use of high-risk medications whenever possible.
10. Monitoring Renal and Hepatic Function: Regularly assess renal and hepatic function in older adults, as these organs are critical for drug metabolism and excretion. Dose adjustments may be necessary to avoid toxicity or suboptimal therapeutic effects.

Assessment Strategies for Drug Interactions in Older Adults

Effective assessment strategies are essential for managing medications and preventing adverse drug events (ADEs) in older adults. As people age, changes in pharmacokinetics (the body’s effect on the drug) and pharmacodynamics (the drug’s effect on the body) become significant factors that healthcare providers must consider when prescribing or managing medications.

Changes With Aging

Aging introduces a range of physiological changes that affect drug absorption, distribution, metabolism, and excretion. These changes necessitate adjustments in drug dosing and careful monitoring to avoid ADEs.

1. Pharmacokinetics:
   • Absorption: While aging itself does not significantly alter drug absorption, changes in gastric pH, reduced gastrointestinal (GI) motility, and decreased absorptive surface can affect how drugs are absorbed. For instance, medications like fluoroquinolones, when taken with iron, can have impaired absorption due to altered gastric conditions.
   • Distribution: With age, there is a decrease in cardiac output, total body water, and serum albumin levels, and an increase in body fat. These changes affect the volume of distribution for both water-soluble and fat-soluble drugs. Water-soluble drugs (e.g., alcohol, lithium) have a higher serum concentration, while fat-soluble drugs (e.g., benzodiazepines) have a prolonged half-life due to increased fat storage.
   • Metabolism: Aging affects the cytochrome P-450 enzyme system in the liver, reducing the metabolism of drugs cleared by this pathway. For example, beta-blockers, which undergo first-pass metabolism in the liver, may require lower doses in older adults.
   • Excretion: The decline in renal function with age, characterized by reduced glomerular filtration rate, renal tubular secretion, and renal blood flow, slows the elimination of drugs from the body, leading to prolonged half-life and increased plasma concentrations.
2. Pharmacodynamics:
   • Changes in receptor sensitivity and number, post-receptor effects, and cellular response to drugs result in altered drug response in older adults. These changes can cause increased sensitivity to drugs, particularly those affecting the central nervous system (e.g., benzodiazepines, opioids) or cardiovascular system (e.g., antihypertensives).

Comprehensive Medication History

A complete medication history is crucial for assessing the potential for drug interactions and adverse reactions. This history should include:

• Medication Allergies: Document all known drug allergies and the type of reaction (e.g., hives, anaphylaxis).
• Prescription Medications: Include all current prescription medications, doses, frequency, route of administration, and any recently discontinued drugs with reasons for discontinuation.
• Over-the-Counter (OTC) Medications: Ask specifically about the use of pain relievers, allergy medications, sinus congestion medications, heartburn treatments, and sleep aids. Determine how often the patient exceeds the recommended dose and whether they read labels or consult a pharmacist about interactions.
• Herbal Remedies and Nutritional Supplements: Include all herbal remedies (e.g., ginkgo biloba, St. John’s wort) and nutritional supplements (e.g., calcium with vitamin D, multivitamins). Understand their frequency and reasons for use.
• Alcohol and Smoking: Document the type and amount of alcohol consumed per day and the type and quantity of tobacco products used.
• Immunizations and Lab Tests: Record past and current immunizations (e.g., flu, pneumonia vaccines) and regular lab tests to evaluate medication levels or side effects (e.g., potassium, digoxin levels, liver and renal function).
• Use of Memory Aids: Assess the use of memory aids like pill dispensers and adherence to medication regimens.

Changes in Drug Metabolism and Excretion

• Cytochrome P-450 System: Many drugs metabolized by the cytochrome P-450 enzyme system, such as cardiovascular drugs, antibiotics, and psychoactive medications, may require dose adjustments in older adults due to reduced enzymatic activity.
• Hepatic Metabolism and Renal Clearance: Drugs that undergo hepatic metabolism and subsequent renal clearance (e.g., diazepam) often have significantly longer half-lives in older adults, requiring careful monitoring and potential dose reductions.

Beers Criteria for Potentially Inappropriate Medication Use

The Beers Criteria, developed by the American Geriatrics Society, serves as a guideline to identify potentially inappropriate medications for older adults. The criteria address:

• Medications to Avoid: Drugs or classes of drugs that should generally be avoided in people aged 65 and older due to their high risk of causing ADEs.
• Medications to Avoid in Specific Conditions: Drugs that should not be used in older persons with certain medical conditions due to increased risk of adverse outcomes.

The Beers Criteria have been incorporated into regulatory guidelines by agencies like the Centers for Medicare and Medicaid Services (CMS) and the Joint Commission (TJC). Using these criteria, healthcare providers can reduce the risk of ADEs by avoiding high-risk medications or using them with caution.

Assessment for Potential Adverse Drug Reactions (ADRs)

ADRs are common in older adults, often due to polypharmacy and multiple medical conditions. The most frequent ADRs in older adults involve cardiovascular medications, diuretics, non-opioid analgesics, hypoglycemics, and anticoagulants. Monitoring for errors, such as incorrect dosages, inadequate patient education, or clinically significant drug-drug interactions, is vital for preventing ADRs.

Preventive Strategies for ADRs

1. Regular Monitoring: Regularly monitor lab values (e.g., drug levels, liver and renal function tests) to detect signs of toxicity early. Nurses should understand that ADRs often present as atypical symptoms such as confusion, falls, lethargy, or depression.
2. Comprehensive Medication Review: Review all medications, including OTC drugs and supplements, to identify potential drug-drug or drug-disease interactions.
3. Patient and Caregiver Education: Educate patients and their caregivers about the importance of adherence to prescribed medications, potential side effects, and the risks of polypharmacy.

Drug-Drug Interactions

Drug-drug interactions occur when two or more drugs are taken simultaneously, leading to synergistic, additive, or antagonistic effects that can cause significant toxicity or reduced therapeutic effectiveness in older adults.

• Examples of Drug-Drug Interactions:
  • Concurrent use of antiparkinsonian drugs, tricyclic antidepressants, antipsychotics, antiarrhythmics, and OTC antihistamines can cause dry mouth, gum disease, blurred vision, constipation, urinary retention, or cognitive deficits.
  • Serious ADEs have been documented with specific drug combinations, such as hypoglycemia in patients taking glyburide with cotrimoxazole or digoxin toxicity in patients co-prescribed clarithromycin.

Preventing Drug-Drug Interactions

1. Use of Interaction Checkers: Utilize computer programs, electronic health records (EHRs), or mobile applications to identify potential drug-drug interactions.
2. Collaboration with Pharmacists: Engage pharmacists in medication reviews and consultations to evaluate the safety of drug combinations and adjust therapy accordingly.
3. Regular Medication Reviews: Conduct periodic medication reviews, especially when new medications are added or existing therapies are changed.

High-Risk Medications

High-risk medications in older adults are those that carry a significant risk of ADEs due to their pharmacologic properties or potential for drug interactions. These include:

• Anticoagulants (e.g., warfarin): High risk of bleeding, particularly with changes in diet, concurrent use of NSAIDs, or other factors affecting coagulation.
• Benzodiazepines and Sedatives: Increased risk of falls, confusion, and sedation; associated with a higher incidence of hip fractures.
• Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): Risk of gastrointestinal bleeding, renal impairment, and cardiovascular events.
• Antipsychotics: Elevated risk of cardiovascular events, falls, and mortality, especially in older adults with dementia.

Mitigating the Risks of High-Risk Medications

1. Lower Dosing and Slow Titration: Start with the lowest effective dose and titrate slowly to avoid overshooting the therapeutic window.
2. Close Monitoring: Monitor for signs of toxicity, side effects, or therapeutic failure, particularly when initiating or adjusting high-risk medications.
3. Deprescribing: Review the need for each medication periodically and consider discontinuing those that are no longer necessary or that pose a high risk relative to their benefit.

Assessment for Potential Drug Interactions

1. Functional Capacity Assessment: Evaluate the older adult’s ability to self-administer medications correctly. Tools like the Mini-Mental State Exam (MMSE) and assessment of activities of daily living (ADLs) can help identify cognitive or physical limitations.
2. Creatinine Clearance Calculation: Use the Cockroft-Gault formula to estimate renal function before prescribing medications cleared by the kidneys, as serum creatinine alone is not a reliable indicator in older adults.
3. Monitoring for Clinical Signs of Interactions: Look for symptoms such as confusion, dizziness, hypotension, or signs of drug toxicity, which could indicate an interaction.

Interactions With Over-The-Counter (OTC) and Herbal Remedies

The interaction between prescription medications and over-the-counter (OTC) or herbal remedies is a significant concern, especially among older adults who often consume a large portion of these products. Unfortunately, these interactions are frequently overlooked during medication reconciliation, hospital admissions, or office visits, potentially leading to adverse drug events (ADEs).

Prevalence and Patterns of OTC and Herbal Remedy Use

Older adults are substantial consumers of OTC medications and herbal supplements. According to studies, around 40% of all OTC drugs are consumed by older adults, with usage increasing with age. For example, in a survey of 1,001 older adults, up to 75% reported using OTCs, and 23% reported using two or more OTCs for chronic conditions within the past month. OTC use has continued to rise over the last decade, alongside increased polypharmacy.

Community-dwelling older adults in the United States typically consume approximately 1.8 OTC medications daily. Additionally, the use of herbal or dietary supplements among older adults has increased significantly, from 14% in 1998 to 26% in 2002. A study found that 68% of older adults use prescription medications concurrently with OTCs, dietary supplements, or both, substantially increasing the risk of drug-drug interactions.

Commonly Used OTC and Herbal Remedies

The most commonly reported prescription or OTC medications among older adults include cardiovascular drugs such as antihyperlipidemic agents, aspirin, hydrochlorothiazide, lisinopril, and metoprolol. The most frequently used dietary supplements are multivitamins or minerals, garlic, coenzyme Q10, omega-3 fatty acids, and glucosamine-chondroitin. These medications and supplements often interact with each other, increasing the risk of ADEs.

Herbal remedies that can adversely affect the cardiovascular system include St. John’s wort, motherwort, ginseng, ginkgo biloba, garlic, grapefruit juice, hawthorn, saw palmetto, danshen, echinacea, tetrandrine, aconite, yohimbine, gynura, licorice, and black cohosh. For instance, herbal agents like Chan Su, danshen, ginseng, and licorice can interfere with digoxin levels. Those that interact negatively with warfarin include St. John’s wort, ginseng, ginkgo biloba, and garlic.

Impact of Specific Herbal Remedies

• St. John’s Wort: This herb is one of the top-selling herbal remedies in the United States, but it can potentially lead to serious adverse reactions. St. John’s wort affects drug metabolism by inducing the cytochrome P-450 enzyme system, where many prescription medications are metabolized. This induction can decrease the plasma levels of drugs such as anticoagulants, immunosuppressants, antidepressants, and antiretrovirals, potentially reducing their effectiveness.
• Ginkgo Biloba: Widely used for cognitive enhancement, ginkgo biloba may increase bleeding risk when taken with anticoagulants like warfarin or antiplatelet agents like aspirin. It can also interact with antiepileptic drugs, potentially lowering the seizure threshold.
• Garlic: Often used for cardiovascular health, garlic has anticoagulant properties and can increase the risk of bleeding when taken with other blood-thinning medications such as warfarin or aspirin.
• Ginseng: Ginseng is used for general wellness and energy enhancement, but it may have either hypotensive or hypertensive effects, interact with warfarin, and cause hypoglycemia when taken with antidiabetic medications.
• Licorice: Known for its anti-inflammatory properties, licorice can raise blood pressure and cause hypokalemia when used with diuretics or corticosteroids.

These examples underscore the complexity and potential dangers of combining prescription drugs with OTC medications and herbal supplements.

Lack of Reporting and Healthcare Provider Awareness

Many older adults do not report their use of OTC medications and herbal supplements to healthcare providers, often because they do not consider these products as medications. Simultaneously, healthcare providers frequently fail to inquire about the use of these remedies, which can lead to unrecognized and potentially dangerous drug interactions. This lack of communication and awareness poses significant risks for drug-drug and drug-disease interactions.

Implications of Unidentified Drug Interactions

Herbal products often lack scientific evidence of safety, regulatory oversight, and reliable information. Therefore, the implications for unidentified drug-drug and drug-disease interactions are substantial, potentially leading to severe ADEs, increased morbidity, and even mortality among older adults.

Medication Adherence Challenges

As people age, they may encounter numerous barriers that decrease their ability to adhere to medication regimens. These challenges can include vision impairment, arthritis, and financial constraints, making medication adherence a complex issue that requires careful nursing assessment.

Barriers to medication adherence include:

• Forgetting to take medications or poor organizational skills.
• Belief that the medication is either not needed, ineffective, or that too many medications are being taken.
• Difficulty taking medications, such as opening bottles or swallowing pills.
• Cost-related concerns, especially when medications are expensive or not covered by insurance.

Strategies to Improve Medication Adherence

Several interventions and strategies can help enhance adherence among older adults:

• Simplify Medication Regimens: Whenever possible, reduce the number of daily doses by prescribing extended-release formulations or combination medications.
• Use Pill Organizers: Tools like weekly pill organizers or automated pill dispensers can help older adults manage their medications effectively.
• Provide Clear Instructions: Educate patients about the importance of their medications, potential side effects, and the risks of non-adherence.
• Monitor Adherence: Utilize strategies such as refill history checks, pill counts, or electronic monitoring devices to assess adherence regularly.

Medication Reconciliation

Medication reconciliation (MR) is the process of ensuring the accuracy and completeness of a patient’s medication regimen during transitions of care. It involves comparing the patient’s current medication list with the physician’s admission, transfer, and discharge orders to identify and resolve discrepancies.

Medication discrepancies between physician-acquired medication histories and comprehensive medication histories during hospital admission are common, occurring in up to 67% of cases. Poor communication at transition points (e.g., admission, transfer, discharge) often results in medication errors, but appropriate MR can reduce these errors.

Performing Medication Reconciliation

MR is typically performed by pharmacists or nurses, sometimes with pharmacist collaboration or computer-based programs. The process includes:

1. Comparison of Medication Lists: Compare the patient’s medications based on patient and family reports or admission and transfer documents with the medication orders at different points of care.
2. Identification of Discrepancies: Identify discrepancies, such as omitted medications, incorrect dosages, or added medications, and resolve them promptly.
3. Collaboration and Communication: Foster communication among healthcare professionals to ensure that all involved parties are aware of any medication changes.

Challenges and Barriers to Effective MR

Barriers to effective MR include lack of confidence in existing institutional safety systems, inconsistent practices, poor communication between health professionals, and the time-consuming nature of the process. Despite these challenges, MR can significantly improve patient safety and reduce ADEs.

High-Risk Medications and Drug Interactions

High-risk medications require special attention due to their potential for severe adverse effects, especially when taken by older adults. Common high-risk medications include:

• Warfarin: Frequently identified as a high-risk medication due to its potential to cause serious bleeding events. Warfarin is highly protein-bound, and its metabolism can be affected by other drugs, herbal supplements, and foods high in vitamin K (e.g., spinach, green tea).
• Antihypertensive Agents: Antihypertensive drugs, such as beta-blockers, diuretics, and alpha-blockers, can cause adverse effects like orthostatic hypotension, dizziness, and confusion. Older adults on multiple antihypertensives should be monitored closely for these side effects.
• Benzodiazepines (BZDs) and Sedatives: These medications pose an independent risk factor for falls, impaired cognition, and urinary retention. They should be used with caution in older adults.
• Antipsychotics: These drugs can increase the risk of falls, mortality, and pneumonia, especially in older adults with dementia. Their use should be closely monitored, and alternative therapies considered when possible.

Mitigating Risks Associated with High-Risk Medications

1. Lower Dosing and Slow Titration: Start with the lowest effective dose and increase slowly to minimize adverse effects.
2. Close Monitoring: Regularly monitor for signs of toxicity, adverse effects, or therapeutic failure.
3. Deprescribing: Review the necessity of each medication periodically and consider discontinuing those that are no longer needed or pose a high risk relative to their benefits.

Overview of Mental Health Disorders in Older Adults

Mental health disorders are not a normal part of aging, yet they are common among older adults. Approximately 20% of individuals over the age of 55 experience mental health disorders, with the most prevalent being anxiety, severe cognitive impairment, and mood disorders. Despite this high prevalence, mental disorders are often underreported in this population, leading to a significant gap in diagnosis and treatment. Older adults, particularly those over 85 years, also have the highest suicide rates, which are more than twice the national average.

Risks Associated with Sedative-Hypnotic Drugs

Sedative-hypnotic drugs significantly increase the risk of adverse events in older adults and should generally be used sparingly and monitored very closely. Benzodiazepines (BZDs), regardless of their half-life, have been associated with cognitive impairment, hip fractures, and falls. In a study of 9,093 patients, older adults taking BZDs were found to be at a higher risk for mobility problems and disability in activities of daily living (ADL). Interestingly, short-acting BZDs did not provide any safety benefits over long-acting agents. The increased plasma concentrations of these drugs in older adults, due to changes in body composition and pharmacokinetics, further heightens the risk of side effects such as oversedation, respiratory depression, confusion, and falls.

Psychoactive Medications

Psychoactive medications include a variety of drug classes such as antidepressants (e.g., tricyclics, selective serotonin reuptake inhibitors or SSRIs), anxiolytic agents (e.g., diazepam, lorazepam), antipsychotics (neuroleptics), mood stabilizers (e.g., lithium), and psychoactive stimulants. These medications are prescribed to stabilize mood, manage agitated behaviors, and treat clinical depression. However, many of these drugs have a narrow therapeutic window, especially in older adults, requiring close monitoring to avoid adverse effects and toxicity. For instance, lithium, a mood stabilizer, interacts with many other drugs and necessitates regular monitoring of blood levels to avoid toxicity.

The half-life of psychoactive drugs is often prolonged in older adults, necessitating extreme caution to prevent inducing delirium, falls, and other traumatic events. Medications like sedatives, hypnotics, BZDs, and antidepressants have been strongly linked with falls, especially in adults over the age of 80. The risk of falls and related injuries is significantly higher in those taking psychotropics, antidepressants, BZDs, hypnotics, neuroleptics, and tranquilizers.

Antidepressants and Their Use in Older Adults

Antianxiety agents like BZDs and sedative-hypnotics are often overprescribed for older adults, whereas antidepressants tend to be underprescribed. It is estimated that nearly 15% of older adults living in the community, 5% in primary care, and 15-25% in nursing homes have significant depressive symptoms. Among the antidepressants, SSRIs are considered a safer choice for older adults due to their lower risk of side effects compared to tricyclic antidepressants. Unlike tricyclics, SSRIs do not cause cardiotoxicity, orthostatic hypotension, or anticholinergic effects. However, SSRIs can cause gastrointestinal side effects such as nausea and anorexia, which can be minimized by starting at low doses and gradually increasing them.

A serious but rare complication of SSRIs is serotonin syndrome, which can occur when more than one antidepressant is used or when SSRIs are combined with certain OTC remedies, such as St. John’s wort.

Use of Antipsychotics in Older Adults

Antipsychotics are frequently used inappropriately as a first-line treatment for older adults presenting with agitation and behavioral problems related to dementia. Evidence-based guidelines suggest that the underlying cause of agitation should be determined (e.g., delirium or pain) and that nonpharmacological interventions should be attempted before resorting to antipsychotics. Most antipsychotics are not FDA-approved for managing agitation in dementia patients and are associated with greater risks than benefits. These drugs should be used with caution due to their potential to cause abnormal, often irreversible, involuntary movements (extrapyramidal symptoms) and an increased risk of falls. Newer antipsychotics, such as clozapine, risperidone, olanzapine, and quetiapine, present a lower risk of movement disorders but still require careful monitoring.

A major study on the use of antipsychotics in Alzheimer’s disease found that the adverse effects outweighed the benefits. In 2004, the FDA issued a warning against the off-label use of antipsychotics for dementia-related symptoms due to the potential for adverse effects.

Anti-Cholinergic Drugs and Their Risks

Medications with high anticholinergic properties pose significant risks to older adults, leading to adverse effects like confusion, agitation, hallucinations, blurred vision, urinary retention, and constipation. Older adults, especially those with dementia, are particularly vulnerable to these effects. In older male adults with benign prostatic hyperplasia (BPH), urinary retention caused by anticholinergic drugs can lead to urosepsis and death.

The risk of adverse effects is heightened when multiple anticholinergic drugs are used concurrently. For instance, an older adult with dementia and BPH taking diphenhydramine (Benadryl) for sleep and oxybutynin (Ditropan) for bladder control may experience additive effects, leading to severe complications such as urinary retention and agitation. This may result in a prescribing cascade, where additional medications are prescribed to manage side effects, further exacerbating the problem.

Anticholinergic effects are not limited to psychiatric medications but also include many OTC antihistamines, sleep aids, intestinal and bladder relaxants, corticosteroids, antihypertensives, antiarrhythmics, and some antibiotics. The Anticholinergic Risk Scale (ARS) helps identify older adults at the highest risk for adverse effects from these drugs.

Cardiotonic Drugs: Digoxin

Digoxin is useful in treating congestive heart failure (CHF) due to systolic dysfunction but is not recommended for CHF from diastolic dysfunction in older adults. Digoxin toxicity is more frequent in older adults, often presenting atypically and resulting in death. Toxicity symptoms include nausea, anorexia, visual disturbances, and, more commonly, symptomatic cardiac disturbances and arrhythmias. Because the therapeutic window for digoxin is narrow and it is water-soluble, older adults are particularly susceptible to toxicity, especially if they have low serum albumin levels.

Care must be taken when prescribing digoxin with diuretics, as this combination can cause hypokalemia and exacerbate renal impairment, further potentiating toxicity. Monitoring renal function and potassium levels is crucial, and the maximum recommended dose for older adults is 0.125 mg.

Hypoglycemic Agents and Older Adults

Hypoglycemic agents carry a high risk of serious adverse effects in older adults. While controlling blood glucose levels is essential to prevent complications of diabetes, strict adherence to disease-specific guidelines for glucose control may lead to overmedication in older adults. Tight glycemic control can result in more harm than benefit, particularly in frail older adults or those with multiple comorbidities.

The American Geriatrics Society (AGS) recommends less stringent glycemic targets for older adults, particularly those who are frail or have limited life expectancy. Oral agents with shorter half-lives are preferred, and insulin is less often recommended unless provided in pre-filled syringes. Metformin is not recommended for those over 80 years due to the risk of metabolic acidosis. Blood pressure and lipid control, along with daily low-dose aspirin, are recommended to reduce vascular complications.

Over-The-Counter Medications

Self-medication with OTC medications, herbal remedies, and dietary supplements is common among older adults and may lead to adverse drug-disease and drug-drug interactions. In a study of older adults attending a hypertension clinic, 86% reported using at least two self-medication practices that could result in adverse interactions. Community-dwelling older adults take about as many OTC drugs as prescription drugs, and low-dose aspirin and NSAIDs are frequently implicated in hospital admissions.

Older adults should be educated about the potential risks associated with combining OTC medications and supplements with prescription drugs. For example, ginkgo biloba and garlic, commonly used supplements, can enhance the anticoagulant effects of warfarin, leading to severe bleeding.

Interventions and Care Strategies for Medication Management in Older Adults

Introduction

Medication management for older adults is a complex process that requires careful assessment, monitoring, and collaboration among healthcare providers. As people age, they are more likely to take multiple medications, including prescription drugs, over-the-counter (OTC) medications, and herbal remedies, which increases the risk of adverse drug events (ADEs) and adverse drug reactions (ADRs). Proper assessment strategies and interdisciplinary care approaches are crucial to reducing these risks and improving health outcomes in older adults.

Comprehensive Medication Assessment

A comprehensive medication assessment starts with obtaining a thorough drug history from the older adult or a reliable informant. Studies indicate that up to 67% of patients have medication history errors at the time of hospital admission, a figure that rises to 83% when nonprescription drugs are included (Tam et al., 2005). This highlights the need for a systematic approach to accurately collect medication histories during hospital admission.

Key Steps in Medication Assessment:

1. Obtain a Complete Medical History:
   • Collect information on all medications, including prescription drugs, OTCs, herbal remedies, vitamins, and supplements (Lau, Florax, Porsius, & De Boer, 2000).
   • Validate the accuracy of the medication history by cross-referencing information from multiple sources, such as patient reports, pharmacy records, and medical charts.
2. Use the “Brown Bag” Method:
   • Encourage older adults to bring all their medications, including OTCs and supplements, to their healthcare provider in a “brown bag” (Nathan et al., 1999). This allows for a thorough review of medication types, dosages, administration instructions, and duration.
   • This method can help identify polypharmacy, multiple prescribers, and potential substance abuse issues, particularly with analgesics, anxiolytics, and sedative-hypnotics.
3. Ask Focused Questions:
   • Inquire about the use of nicotine, alcohol, recreational drugs, and herbal or folk remedies. Use specific questions to gather detailed information about the frequency, dosage, and context of use (Astin et al., 2000; Lau et al., 2000).
   • Provide a list of common herbal remedies and ask the patient to identify any they are using (Tachjian et al., 2010).
4. Evaluate for Duplicate Medications:
   • Assess for duplicate medications that may have different trade names but the same active ingredients, especially those containing acetaminophen or other common components (Astin et al., 2000).

Medication Reconciliation (MR)

Medication reconciliation is critical in verifying a patient’s actual medication regimen during transitions of care, such as hospital admission, discharge, or transfer. This process involves comparing the patient’s current medication list with the physician’s orders to identify and resolve discrepancies.

Key Strategies for Effective MR:

• Perform Medication Reconciliation at Key Transition Points:
  • Ensure MR is done at hospital admission, discharge, and across the continuum of care to avoid medication errors and discrepancies (Gleason et al., 2004; Nickerson et al., 2005; Tangalos & Zarowitz, 2006).
  • Use a medication discrepancy tool to facilitate the identification and resolution of discrepancies across different settings (University of Colorado Health Sciences Center, 2005).
• Monitor New Symptoms:
  • Consider the possibility that new symptoms may be caused by an ADR before adding new medications to treat the symptoms (Petrone & Katz, 2005; Rochon, 2010).
  • Avoid the prescribing cascade by using nonpharmacological interventions and treatments before resorting to new medications.

Ongoing Monitoring and Collaboration

Continuous monitoring of patients for potential drug toxicity, especially for high-risk medications, is essential. Nurses should employ technologies such as personal digital assistants (PDAs) to access databases on high-risk medications and drug interactions.

Key Monitoring Strategies:

1. Monitor for Toxicity and ADRs:
   • Be vigilant for signs of toxicity, particularly in drugs with a high prevalence of adverse effects (see Beers criteria; Beers, 1997; Beers et al., 1992).
   • Consider medications as the underlying cause when falls or other adverse events occur, especially when high-risk drugs like diuretics or psychotropics have been recently added.
2. Collaborate with Interdisciplinary Teams:
   • Work closely with other healthcare professionals, including pharmacists, physicians, nurse practitioners, and social workers, to reduce the number of ADEs and ADRs, many of which are preventable (Hanlon et al., 2001).
   • Form a medication care team with clearly defined roles and responsibilities to review medications at admission and discharge using evidence-based practices.

Interventions at Discharge

Discharge interventions are crucial to ensure continuity of care and prevent medication errors after a patient leaves the hospital.

Key Discharge Interventions:

• Pharmacist-Led Interventions:
  • Pharmacists can use computer-based programs to review medication lists for potential drug-drug interactions, drug-disease interactions, and inappropriate medications for older adults. Age-specific alerts can help reduce inappropriate prescribing (Simon et al., 2006).
• Computerized Physician Order Entry Systems:
  • These systems can prevent a significant proportion of medication errors related to dose, frequency, and route (AHRQ, 2001).
• Medication Interaction Alerts:
  • Alerts can reduce the frequency of prescribing potentially interacting medications (Feldman et al., 2006).
• Communication with Community Pharmacy and Primary Care Providers:
  • Pharmacists can communicate the hospital drug regimen to the community pharmacy, primary care provider, and other levels of care to ensure continuity and safety.
• Social Worker Involvement:
  • Social workers can assess issues related to medication access, costs, caregiver support, and other barriers to medication adherence. They can also help plan for home care needs and facilitate discharge interventions.

Patient Education and Counseling

Educating and counseling patients about their medications is a key strategy in preventing medication errors and promoting adherence.

Key Patient Education Strategies:

1. Use Devices to Accommodate Impairments:
   • Recommend devices that address barriers to medication adherence, such as easy-to-open lids for those with arthritis. Consult with occupational therapists as needed.
2. Assess Health Literacy:
   • Determine whether the patient understands what each medication is for, how often it should be taken, and under what circumstances (e.g., with food). Use the “teach-back” method to verify understanding (Hutchison et al., 2006; Schillinger et al., 2003).
3. Assess Ability to Recognize Medications:
   • Ask the patient to describe how they take their medications, including the use of generic versus brand names. Provide written instructions if necessary (Muir et al., 2001).
4. Assess Beliefs and Concerns About Medications:
   • Engage the patient in discussions about their beliefs and concerns regarding their medication regimen. If a medication is not perceived as useful or is causing adverse effects, consider alternatives.
5. Discuss Medication Costs:
   • Address concerns about the costs of medications, particularly for new or expensive drugs. Discuss Medicare Part D and explore generic alternatives or other strategies to manage costs.
6. Consider Social Supports and Barriers:
   • Evaluate the availability of family or social support to assist with medication adherence and monitor changes dictated by insurance or medication coverage plans.

Empowering Patients in Their Care

Encouraging patients to take an active role in their medication management can lead to better health outcomes.

Strategies for Empowering Patients:

• Provide Information and Encourage Involvement:
  • Give patients the necessary information and opportunities to make informed decisions about their medications. This can prevent actions like abruptly discontinuing a medication without tapering, which could lead to ADRs (NCC MERP, 2001).
• Involve Patients in Decision-Making:
  • Patients who are involved in decisions about their care are less likely to make mistakes that could lead to ADRs. Discuss the risks and benefits of their medications and encourage them to ask questions and express concerns.

Conclusion

Effective medication management for older adults requires a comprehensive approach that includes thorough assessment, ongoing monitoring, patient education, and interdisciplinary collaboration. By implementing evidence-based strategies and involving patients in their care decisions, healthcare providers can reduce the risk of ADEs and ADRs, improve medication adherence, and enhance the overall health and well-being of older adults.