Prediction Tool Needed to Prevent Adverse Drug Reactions in Older Patients

Older patients are more susceptible to adverse drug reactions (ADRs) because of comorbidities, cognitive and functional impairment, polypharmacy, and changes in pharmacokinetics and pharmacodynamics. Yet, there is currently no tool that could effectively predict possible ADRs.

General practitioners (GPs) are often under time constraints that make it difficult to adequately predict ADRs that could potentially hospitalize an older patient, but a prediction tool would be able to do this quickly and accurately, according to a study published by Clinical Interventions in Aging. Previous studies show that ADR-related hospital admissions accounted for 6 to 12% of all admissions for older people.

These hospitalizations can potentially lead to fatal outcomes especially when severe ADRs, such as hemorrhage, along with other hematological disorders and acute renal failure. Although some ADR-related hospitalizations are unavoidable, the researchers said that more than half are preventable, according to the study.

The preventable admissions can be due to improper doses, missed drug interactions, or drug allergies. Other studies have found that only 18.6 to 28% of admissions are unavoidable.

The researchers found that gastrointestinal disorders, cardiovascular, and metabolic/endocrine complications are the most frequent ADRs that cause hospitalization. Although many other studies have examined ADRs among older patients, predictions for these reactions are still not fully understood.

Factors such as age can significantly increase the likelihood of having an ADR with each additional year of life. The researchers also said that the number of drugs taken can increase the risk of ADR from 10% to as high as 75%.

Repeat admissions are more likely for patients with comorbidities such as heart disease and failure, depression, diabetes, and peripheral vascular diseases, among others, according to the study. Exposure to potentially inappropriate medications was also found to increase ADR-related hospitalization.

Prediction tools that gather information could potentially decrease the amount of ADR-related hospitalizations among older patients. Currently, ADRs are difficult to predict since the symptoms could be misinterpreted as a new condition or part of an existing condition.

This could lead to another medication, which increases the risk of an adverse reaction. It is also possible that more than 1 medication could cause the ADR, and patients may have cognitive impairments that could make it difficult to communicate ADRs, according to the study.

Proposed ADR risk prediction tools typically fall short in areas such as not including significant risk factors or using a younger population. An accurate prediction tool would include a list of predictive factors based on previous studies, validated ADR prediction tools, and clinical experience, according to the study.

Creating a novel efficient prediction tool is needed in the older population since it could potentially prevent a large amount of avoidable ADR-related hospital admissions, the study concluded.