Tablets, Capsules, Liquids: Polypharmacy and the Elderly

Polypharmacy in the Elderly

Aging. One of life’s inevitabilities that some people embrace and others fight. Regardless of one’s attitude, getting older is a certainty. Becoming “elderly” is someone who is at least 65 years old, by most definitions. However, many of these people do not require geriatric care until they are 70, 75, or even 80 years old.

EMS professionals assess and treat many patients in this age range daily, partially due to the longevity of the Baby Boomer generation—individuals born between 1946 and 1964. Keep in mind that aging is a unique process. A 75-year-old with multiple ailments and the same-aged healthy patient metabolize drugs differently.

Several physiological changes occur with aging. The elasticity of the lungs decreases, as does vital capacity. Vascular peripheral resistance increases, leading to hypertension. The kidneys atrophy, and eventually decrease in blood flow, filtration, secretion, and reabsorption. Combined with the decreased activity of certain liver enzymes and increased serum drug levels, the likelihood of adverse drug effects is high. Decreases in lean body mass, muscle mass, total body water, and increased cellular resistance to insulin and glucose intolerance occur. This causes a higher incidence of diabetes, dehydration, and loss of strength and balance—resulting in a higher incidence of syncope, falls, and increased drug elimination time.

Polypharmacy

The multiple pathologies these patients live with many times require EMS intervention and/or transportation. As the number of medical problems increases with their age, these patients eventually are evaluated and managed by multiple specialist physicians. However, communication between these physicians is typically minimal to non-existent. This leads to multiple medications being prescribed and taken by the elderly patient—potentially resulting in dangerous drug interactions. Multiple medical conditions alone pose diagnostic challenges. Add to the mix multiple medications with the various signs and symptoms they produce, and/or ones they may mask, and diagnosis and appropriate interventions become very difficult for the EMS professional. Additionally, large numbers of prescription medications have a correlation to poor health outcomes.

There are other negative consequences associated with polypharmacy. These include adverse drug events, drug-drug interactions, non-adherence to taking medications, cognitive impairment, falls, and compromised nutritional status.

Adverse Drug Events for the Elderly

A population-based study discovered that geriatric patients taking five or more medications had an 88% increased risk of experiencing an adverse drug event compared to those who were taking fewer medications.

Anticoagulant drugs, antidiabetic drugs, and drugs with a narrow therapeutic index (e.g., digoxin and phenytoin) account for almost 50% of all adverse drug events in the elderly.

Therapeutic index is a ratio that compares the blood concentration at which a drug becomes toxic and the concentration at which the drug is effective. If the therapeutic index is narrow (the difference between the two concentrations is very small), even though the drug dose is appropriate, the patient can easily become toxic from taking one extra dose with their normal dose.

Commonly prescribed medications cause a variety of side effects in the elderly patient. These include: aspirin (gastrointestinal bleeding), digitalis preparations (toxicity, depression), antidepressant medications (altered mental status, cardiac, seizures), loop diuretics (incontinence), over-the-counter sympathomimetics (urinary retention), medications for hypertension (dizziness, syncope), benzodiazepine sedatives (falls), and narcotic analgesics (altered mental status, constipation/impaction).

Thus, EMS professionals may observe a wide variety of signs, symptoms, and complaints in an elderly patient that takes multiple medications.

Drug Interactions

Drug interactions are more likely to occur as the elderly patient’s number of medications increases. One particular study determined that a patient taking 5-9 medications had a 50% probability of an interaction, whereas the risk increased to 100% when a patient was taking 20 or more medications.

A drug interaction occurs when two medications, taken together, result in a pharmacologic change of at least one of the medications, either magnifying or reducing the affected medication’s action. Mixing alcohol or over-the-counter medications with prescription medication may enhance its therapeutic effect and result in toxicity.

Drug interactions can also alter the rate of drug metabolism. Many commonly prescribed medications suppress specific liver enzymes that are responsible for breaking down other ingested medications. As more of the liver’s detoxification ability changes, drug metabolism is delayed. This results in multiple medications remaining in the patient’s bloodstream longer, prolonging their effects.

Medication Non-adherence

Medication non-adherence is associated with potential disease progression, hospitalization, and adverse drug effects. Non-adherence rates in community-dwelling elderly adults have been reported to be between 43-100%.

Multiple medications that an elderly patient requires enhances this problem. There are several issues associated with non-adherence, including:

• Forgetting to take their medication: Patients with Alzheimer’s and other forms of dementia, as well as the average aging patient, become forgetful. This may result in not taking a dose at all or taking a second dose by mistake. If a patient is depressed, they may not be motivated to fill their prescriptions or take them after getting them filled.

• Inability to afford their medications: A large percentage of senior citizens live on fixed incomes. With the rising cost of medications, patients may have to decide between paying for food or multiple medications. Some medications need to be taken with food; otherwise, unwelcome side effects occur. Elderly adults have been known to cut pills in half, skip doses, or skip meals to save money.

• Failure to complete/maintain the entire course of therapy: A common scenario is a patient taking antibiotics who feels better after a few days and stops taking the medication, leading to worse infections. Patients on diuretics may realize that stopping their medication reduces bathroom trips, but this can lead to complications requiring EMS intervention.

• Problems with the container: Childproof caps can also become elderly-proof, especially for patients with arthritis. Poor eyesight may prevent patients from reading labels or small print, leading to incorrect dosages.

Cognitive Impairment

Cognitive impairment, seen with both delirium and dementia, has been associated with polypharmacy. A study in hospitalized elderly adults determined that increasing the number of medications was a risk factor for developing delirium.

Another study in elderly patients with dementia reported that those who experienced a fall had an increased prevalence of polypharmacy.

Several drugs, particularly psychotropic medications (e.g., Xanax, Zoloft, Celexa, Prozac, Ativan, Lexapro), can cause cognitive impairment.

Falls

After aging, polypharmacy may be the most common risk factor for falls in older adults. An analysis of over 800 ED patients aged greater than 65 years old found drugs given for GERD and peptic ulcer disease, analgesics, anti-Parkinson drugs, nasal drugs, medicated eye drops, antipsychotics, and antidepressants were significantly associated with EMS calls for recurrent falls.

In another study of elderly adults, the risk of experiencing a fall increased by 7% for each additional medication prescribed.

There are specific drug interactions that may lead to falls that deserve special attention. Antidiabetic agents (sulfonylurea) when taken with beta-blockers or antibiotics may cause acute hypoglycemia and possible falls. Patients on antihypertensive therapy (especially calcium channel blockers) are at risk for orthostatic hypotension, leading to falls, especially if combined with erythromycin or clarithromycin.

Opioids such as codeine or tramadol, when taken with serotonin-selective reuptake inhibitors (Celexa, Lexapro, Prozac, Paxil, Zoloft), can also increase the likelihood of falls.

Nutrition

Polypharmacy has been reported to affect a patient's nutritional status. A survey of community-dwelling elderly adults found that polypharmacy was associated with a reduced intake of fiber, fat-soluble and B vitamins and minerals, as well as an increased intake of cholesterol, glucose, and sodium.

The diseases and conditions most frequently implicated in the development of malnutrition include:

• higher age groups, particularly 80 years and older

• chronic respiratory diseases

• digestive tract diseases

• tumors

• neurodegenerative diseases, chronic infections, and psychiatric diseases

These patients are often managed with long-term therapy, involving multiple prescribed medications.

Nearly 50% of older adults take one or more medications that are not medically necessary, and research has established a strong relationship between polypharmacy and negative clinical outcomes. Polypharmacy is common among the elderly population due to the need to treat various disease states that develop as a person ages. Unfortunately, this increase in the use of multiple medications comes with the risk for negative health outcomes, including higher healthcare costs, adverse drug events, drug interactions, medication non-adherence, and potential for traumatic falls, TBI, and death.

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