2.4 POLYPHARMACY IN THE ELDERLY
2.4.1 Factors contributing to polypharmacy
• Patient related factors
Advancing age; polypathologies; poly-diseases; poly-susceptibilities; multiple symptoms; OTC remedies - many polycomponent; poor nutrition; poor organ function; forgetfulness; loss of lean body mass; unsteadiness; subliminal dysfunctions _ especially psychoneurological; poverty; disablement; neglect; hypochondriasis; and many more factors may contribute to polypharmacy. Thus, largely, but by no means entirely due to their often chronic polypathologies, we find the elderly receiving a grossly disproportionate excess of medications. The bottom line is that the risk of adverse events increases dramatically with the number of drugs administered.
• Medicament related factors
Medicament-related risks include: poly-drugs, especially polycomponent; dose too large, and too often; the medication may be entirely inappropriate; but even if appropriate it may also be dementing, constipating, urine-retaining, mineral losing, diabetogenic, psychoneurologically decompensating, sodium and water retaining, broncho-constricting, allergenic, etc. These side effects may then be treated. The Medical Model influence healthcare providers to regard every sign or symptom of a disease as a medical problem to be controlled or cured - usually with medications.
Healthcare providers believe not only that "there is a pill for every ill," but that "every ill deserves a pill!" (Mallet, 1996). Thus, poly-pharmacy in the care of the elderly continues to increase.
Poly-pharmacy is also due to copious prescribing, multiple prescribers, lack of a primary provider to coordinate drug therapy, the use of multiple pharmacies, drug regimen changes, hoarding of medications, and self-treatment. OTC medications are full of potential problems and surprises. Users do not regard many as medicines, so
Drug relltted probletm among geriatric out-patients at a public sedor hospital: An intervention study 44
that unless specific enquiry is made, it may seem that there are no OTC's in use. Many of the OTC medicines are also poly-consti~uent. Too many medications means more medications to treat adverse effects, which give more adverse effects, and a vicious cycle is so easily established (Mallet, 1996).
Pressures for increased drug use in the elderly will continue to mount with improved diagnosis of disease and marketing of drugs to treat symptoms and diseases.
Although many authors condemn multiple drug use in the elderly, more and more recommendations for preventive drug therapy are published. Calcium and estrogen have been recommended for prevention of osteoporosis, hypercholesterolemic agents have been suggested to prevent coronary artery disease in a large percentage of the elderly, and daily aspirin therapy to prevent myocardial infarcts has been suggested for a large segment of the population.
If one considers the prevalence of potentially treatable disease in the elderly, it can be concluded that multiple drug therapy will be the rule, not an exception. Although pressures to increase drug use in the elderly will continue to rise, several factors may mitigate against multiple drug use in this population. These factors include:
the development of drugs with more precise mechanisms of action,
increased education for physicians who prescribe for the elderly people, and development of computer software to assist in selection of more appropriate drugs and to screen for drug-disease and drug-drug interactions.
Currently few available drugs have precise and specific mechanisms of action.
Amitriptyline is useful for alleviating depression in the elderly but it has anti- cholinergic, arrhythmogenic, and alpha-adrenergic blocking effects that may aggravate diseases commonly present in this age group (Merck Manual, 1992). Drugs likely will be developed in the future with more precise actions and fewer adverse effects. New drugs will be marketed that can cause a specific receptor to control illness rather than affecting mUltiple receptor types throughout the body.
In the past, two or three drugs were often necessary to effectively treat hypertension, congestive heart failure, or peptic ulcer disease but in the future more potent drugs
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Drug reloted problems among geriatric out-patients at a public sector hospital: An intervention study
will be available. This will allow physicians to prescribe one drug to treat a disease that required multiple drug therapy a decade ago. For example, ten years ago patients with peptic ulcer disease would be treated with multiple daily doses of antacids and anticholinergics, but today single-drug therapy with histamine2-receptor blocking drugs may be sufficient.
Greater emphasis on geriatric education has already occurred in medical curricula and even more emphasis is needed for the future. Increased education is needed to prepare physicians to deal with special psychosocial needs of the elderly and to assess the benefit-to-risk ratio of drug therapy. Physicians need to be aware of the multiple disease states present in older people and the problems resulting from polypharmacy.
Current prescribing practices of a "pill for every ill" need to be modified to a careful assessment of the potential benefits of prescribing a medication with the possible adverse effects (Mallet, 1996). A greater reliance of non-drug therapies such as diet modification, exercise, and counseling will be needed to decrease the problem of multiple drug use in the elderly.
Elderly people should also be educated about the benefits and risks of prescribed and nonprescribed medication. Patients often state that they take many medications because doctors prescribed them, whereas physicians state they prescribe many drugs because patients demand them. Education should be directed at patients who consume drugs and physicians who prescribe them.
Physicians cannot be expected to remember the adverse effects, drug-drug, drug- disease, and drug-diet interactions of hundreds of drugs used by elderly patients.
However, this information can be readily yategorized and stored in a computer and used to aid physicians in their attempt to prescribe safer, more effective, and less costly drugs for the elderly. Pharmacists who monitor drug therapy of elderly patients can also use computers. Implementing these types of software programs in physicians' offices and in pharmacies would have a major impact on identifying therapeutic duplication and antagonism and reducing the number of medications used by older people. Computer software development to perform the above functions should be a high priority of federal agencies concerned with geriatric care.
Drug relilled problems among geriatric out-patients at a public sector hospital: An intervention study
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The trend of multiple drugs usage will likely increase in the future as a result of an increasing burden of chronic disease and success of researchers who develop new drugs. Increased educational efforts concerning the hazards of multiple drug therapy should be directed to physicians who prescribe drugs for the elderly and to consumers who use drugs. A high priority should be placed on the development of computer systems to aid physicians in prescribing more appropriately for older people and to aid pharmacists who monitor drug therapy of their patients (Stewart, 1990).
Often, the result is that similar compounds are used simultaneously, for example two or more benzodiazepines or antipsychotics: or drugs with similar properties are used concurrently, for example a number of drugs with anti-cholinergic properties.
Polypharmacy increases the risk of prescribing errors and needs to be addressed (Burgess, 1997). Studies have shown that on average elderly people took three to four different medications (both prescribed and aT C) (FIP Lisbon Congress, 1994).