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Prevention of Iatrogenic Complications in Older Adults


Magda Lenartowicz

, MD, Altais Health Solutions

Reviewed/Revised May 2023

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 for Iatrogenic Complications

The first step in prevention is to identify patients at high risk. Risk factors include having multiple chronic diseases, having multiple clinicians, taking multiple medications, and being hospitalized.

Multiple chronic diseases

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 medications (polypharmacy Overview of Drug Therapy in Older Adults Prevalence of prescription drug use increases substantially with age. Survey data from 2010–2011 indicate that almost 90% of older adults regularly take at least 1 prescription drug, almost... read more ) and inappropriate medications

Taking multiple medications concurrently and having multiple chronic diseases markedly increase risk of adverse drug-drug interactions Drug-Related Problems in Older Adults Drug-related problems are common in older adults and include drug ineffectiveness, adverse drug effects, overdosage, underdosage, inappropriate treatment, inadequate monitoring, nonadherence... read more or drug-disease interactions Drug-disease interactions Drug-related problems are common in older adults and include drug ineffectiveness, adverse drug effects, overdosage, underdosage, inappropriate treatment, inadequate monitoring, nonadherence... read more . Risk of such interactions is particularly high among patients who are undernourished or who have chronic kidney disease Chronic Kidney Disease Chronic kidney disease (CKD) is long-standing, progressive deterioration of renal function. Symptoms develop slowly and in advanced stages include anorexia, nausea, vomiting, stomatitis, dysgeusia... read more Chronic Kidney Disease . Also, certain medications have an especially high risk of adverse effects Drug Categories of Concern in Older Adults Some drug categories (eg, analgesics, anticoagulants, antihypertensives, antiparkinsonian drugs, diuretics, hypoglycemic drugs, psychoactive drugs) pose special risks for older adults. Some... read more in older adults, due to changes in body composition and medication metabolism. Specific examples include anticholinergics such as diphenhydramine, benzodiazepines and other sleep aids (eg, zolpidem), opioids, antipsychotics, anticoagulants, and NSAIDs (see Beers criteria Potentially Inappropriate Drugs in Older Adults (Based on the American Geriatrics Society 2019 Beers Criteria® Update) Potentially Inappropriate Drugs in Older Adults (Based on the American Geriatrics Society 2019 Beers Criteria® Update) ).


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 to Prevent Iatrogenic Complications

Interventions that can prevent iatrogenic complications include the following.

Care management

Care managers facilitate communication among health care professionals, 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 care management.

Geriatric interdisciplinary team

A geriatric interdisciplinary team Geriatric Interdisciplinary Teams Every 4 years, the US Department of Health and Human Services (HHS) updates its strategic plan and defines its mission and goals. The HHS strategic plan for 2022 to 2026 includes the following... read more 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

Acute and emergency care for the elderly units

These acute care 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. Geriatric emergency department care units focus on the unique needs (including care transitions and multidisciplinary care) of older patients.

Advance directives

Patients are encouraged to prepare advance directives Advance Directives Advance directives are legal documents that extend a person's control over health care decisions in the event that the person becomes incapacitated. They are called advance directives because... read more , 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.

Drugs Mentioned In This Article

Drug Name Select Trade
Aid to Sleep, Alka-Seltzer Plus Allergy, Aller-G-Time , Altaryl, Banophen , Benadryl, Benadryl Allergy, Benadryl Allergy Children's , Benadryl Allergy Dye Free, Benadryl Allergy Kapgel, Benadryl Allergy Quick Dissolve, Benadryl Allergy Ultratab, Benadryl Children's Allergy, Benadryl Children's Allergy Fastmelt, Benadryl Children's Perfect Measure, Benadryl Itch Stopping, Ben-Tann , Compoz Nighttime Sleep Aid, Diphedryl , DIPHEN, Diphen AF , Diphenhist, DiphenMax , Dytan, ElixSure Allergy, Genahist , Geri-Dryl, Hydramine, Itch Relief , M-Dryl, Nighttime Sleep Aid, Nytol, PediaCare Children's Allergy, PediaCare Nighttime Cough, PediaClear Children's Cough, PHARBEDRYL, Q-Dryl, Quenalin , Siladryl Allergy, Silphen , Simply Sleep , Sleep Tabs, Sleepinal, Sominex, Sominex Maximum Strength, Theraflu Multi-Symptom Strip, Triaminic Allergy Thin Strip, Triaminic Cough and Runny Nose Strip, Tusstat, Unisom, Uni-Tann, Valu-Dryl , Vanamine PD, Vicks Qlearquil Nighttime Allergy Relief, Vicks ZzzQuil Nightime Sleep-Aid
Ambien, Ambien CR, Edluar, Intermezzo, Zolpimist
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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