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Prevention of Iatrogenic Complications in Older Adults


Magda Lenartowicz

, MD,

Last full review/revision Oct 2020| Content last modified Oct 2020
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Iatrogenic complications are more common and often more severe among older adults than among younger patients. These complications include adverse drug effects (eg, interactions), falls, nosocomial infections, pressure ulcers, delirium, and complications related to surgery. Prevention is often possible.

Risk Factors

The first step in prevention is to identify patients at high risk. Risk factors include the following.

Multiple chronic diseases

The greater the number of chronic diseases, the greater the risk that treatment of one disease will exacerbate others. For example, treatment of arthritis with a nonsteroidal anti-inflammatory drug (NSAID) may exacerbate heart failure, coronary artery disease, or chronic gastritis.

Multiple physicians

Having multiple physicians can result in uncoordinated care and polypharmacy. Consultation among multiple physicians every time one of them sees a common patient is difficult. As a result, a patient’s therapeutic regimen is frequently changed without the input of the patient’s other physicians, thereby increasing risk of iatrogenic complications.

Multiple drugs ( polypharmacy ) and inappropriate drugs

Taking multiple drugs concurrently and having multiple chronic diseases markedly increase risk of adverse drug-drug or drug-disease interactions. Risk of such interactions is particularly high among patients who are undernourished or who have renal failure. Also, certain drugs have an especially high risk of adverse effects in older adults, due to changes in body composition and drug metabolism. Specific examples include anticholinergics such as diphenhydramine, benzodiazepines and other sleep aids (eg, zolpidem), opioids, antipsychotics, anticoagulants, and NSAIDs (see Beers criteria).


Risks due to hospitalization include hospital-acquired infection, polypharmacy, and transfusion reactions. Hospitalized patients who have dementia or who are immobilized (eg, after surgery) are at high risk of iatrogenic complications (eg, pressure sores, deep venous thrombosis, urinary retention, delirium).

Medical technology may contribute to iatrogenic complications, including sudden death or myocardial infarction after valvular replacement surgery, stroke after carotid endarterectomy, fluid overload after transfusions and infusions, unwanted prolongation of life via artificial life support, and hypoxic encephalopathy after potentially life-prolonging cardiopulmonary resuscitation (CPR).


Interventions that can prevent iatrogenic complications include the following.

Care management

Care managers facilitate communication among health care practitioners, ensure that needed services are provided, and prevent duplication of services. Care managers may be employed by physician groups, health plans, or community or governmental organizations. Frail older patients benefit the most from case management.

Geriatric interdisciplinary team

A geriatric interdisciplinary team evaluates all of the patient’s needs, develops a coordinated care plan, and manages (or, along with the primary care physician, co-manages) care. Because this intervention is resource-intensive, it is best reserved for very complex cases. Geriatric interdisciplinary teams sometimes focus on specific issues related to aging, such as risk and prevention of falls, assessment of frailty (especially before surgery or cancer treatment), and dementia diagnosis and care.

Pharmacist consultation

A pharmacist can help prevent potential complications caused by polypharmacy and inappropriate drug use.

Acute care for the elderly units

These units are hospital wards with protocols to ensure that older patients are thoroughly evaluated for potential iatrogenic problems before problems occur and that such problems are identified and appropriately managed.

Advance directives

Patients are encouraged to prepare advance directives, including designation of a proxy to make medical decisions. These documents can help prevent unwanted treatment for critically ill patients who cannot speak for themselves.

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