Medication-Related Admissions in Older People

Abstract

Background: Medication-related admissions are an important cause of hospital admissions in older people. The scope for prevention is less clear.

Objectives: To characterize medication-related hospital admissions in older people and assess their preventability.

Methods: This was a cross-sectional, observational study conducted over 3 months. A pharmacist based in the medical admissions ward of a north London hospital screened all patients aged ≥65 years. A specialist physician assembled additional information, which was presented to a multi-professional panel to confirm attribution and preventability. A total of 409 patients were screened, of whom 14% (95% CI 10.6, 17.4) had medication-related problems, 6.4% (95% CI 4.0, 8.8) were admitted because of medication-related problems and 3.9% (95% CI 2.0, 5.8) were considered to have preventable medication-related problems. Medicines to prevent or treat cardiovascular disease were implicated in 69% (18/26) of the medication-related admissions and 69% (11/16) of preventable medication-related admissions. Amongst hospitalized patients, admission attributed to adverse drug reaction was more likely as the number of medications being taken increased, and admission attributed to undertreatment was more likely as the number of pre-existing conditions increased.

Conclusion: Medication-related admissions are common in older people and over half are preventable. Morbidity associated with medicines used for cardiovascular disease is important. There is a difficult balance to be struck between avoiding iatrogenic illness in older people and ensuring they benefit from medications for pre-existing conditions. Opportunities exist for improving the delivery of care to reduce adverse outcomes.

Appendices

Appendices

Appendix 1

Checklist for decision-making on attribution of admissions to medication-related problems and on preventability of medication-related admission.

Assessment of attribution:

• presence of a known adverse drug reaction or toxic reaction, or effect of inadequate treatment;

• presence of a reasonable temporal relationship between commencement of the drug therapy and the onset of the adverse reaction;

• the adverse reaction disappeared on reducing or stopping the drug, or on administration of a suitable antagonist;

• the symptom or event could not be explained by any other known condition or predisposition of the patient;

• laboratory tests showed levels outside the therapeutic range or metabolic disturbances that explained the symptoms;

• the patient had had the same reaction following previous exposure to the same or a similar drug;

• it is unlikely that the admission would have occurred in the absence of medication-related morbidity.

Assessment of preventability:

• the suspected drug was judged to be contraindicated given the patient’s clinical history and other medications;

• the drug was unnecessary, or an alternative, safer option could have been prescribed given the patient’s history and other medications;

• there is good evidence that a medication which the patient was not taking could have averted the outcome;

• the dosage used by the patient was different from accepted recommendations;

• the patient had not been counselled adequately on drug use, and was unclear on dose or frequency of administration;

• it is unlikely that the patient’s illness would have precipitated this particular admission irrespective of drug therapy.

Appendix 2

For details on medication-related problems contributing to preventable medication-related admissions, see table A1.

Table A1

Medication-related problems contributing to preventable medication-related admissions