Continuity and adherence to long-term drug treatment by geriatric patients after hospital discharge: a prospective cohort study.

BACKGROUND: Increased life expectancy is associated with an increased prevalence of chronic diseases and drug consumption. Changes often occur in the medication regimen after hospitalization. The extent and nature of these changes and the adherence of elderly patients have not yet been fully investigated.
OBJECTIVE: To investigate the extent and reasons for modifications to the medication regimens of elderly patients and their adherence to treatment during the first month following hospital discharge.
METHODS: This was a prospective cohort study of 198 patients aged>or=65 years in the Acute Geriatric Ward, Beilinson Hospital, Rabin Medical Center, Israel. Clinical, demographic and medication regimen data were recorded for all patients at an interview conducted prior to discharge. After 1 month, the patient, caregiver or general practitioner (GP) were interviewed regarding the extent and reasons for modifications to the medication regimen and adherence to treatment.
RESULTS: At 1-month post-discharge, on average, 36.7% of patient medications had been modified compared with the discharge prescription. No modification was found in 16% of patients. During the observation month, 62% of prescribed long-term medications were taken without modification as recommended at discharge and during follow-up, 50% of all changes were characterized by the addition of a drug or an increase in dosage, and 26%, 16% and 8% consisted of cancelling, omission or switching within the same medication type, respectively. Seventy percent of medication regimen changes were based on specialists' recommendations or secondary to a change in the patients' medical state, and 13%, 8%, 3% and 6% were as a result of poor adherence, adverse effects, administrative restrictions and other reasons, respectively. There was no correlation between medication regimen change and age, gender, physical function, cognitive function and length of hospital stay. Patients discharged home experienced less regimen modification than those discharged elsewhere (p=0.02). Patients who visited their GP only once experienced less regimen modification (p=0.03). Regression analysis showed that the only factors affecting medication regimen changes were GP visits and chronic diseases (p<0.01, R2=0.09). The overall mean adherence among 145 home-dwelling patients was 96.7%. Twenty-seven percent and 6% were under- and over-adherent, respectively, to at least one drug; under-adherence was more widespread than over-adherence. No correlation was found between the overall mean adherence and other clinical parameters or regimen change. However, non-adherence to at least one drug was associated with more medication regimen changes (p=0.001), was more common in patients discharged with prescriptions for seven or more drug types per day (p=0.01) and was associated with failing to visit the patient's GP 1 month after discharge (p=0.02).
CONCLUSION: The majority of elderly patients experienced modifications in their medication regimen during the first month following hospital discharge. Thirty percent of patients were non-adherent to at least one drug. To improve adherence to a hospital medication regimen, patients should be encouraged to visit their GP and the number of long-term drugs should be reduced.