Potentially inappropriate prescribing and adverse health outcomes in community dwelling older patients

Aims: This study aimed to determine the association between potentially inappropriate prescribing (PIP) and health related outcomes [adverse drug events (ADEs), health related quality of life (HRQOL) and hospital accident and emergency (A&E) visits] in older community dwelling patients.

Methods: A retrospective cohort study of 931 community dwelling patients aged ≥70 years in 15 general practices in Ireland in 2010. PIP was defined by the Screening Tool of Older Person's Prescriptions (STOPP). ADEs were measured by patient self-report and medical record for the previous 6 months and reviewed by two independent clinicians. HRQOL was measured by the EQ-5D. A&E visits were measured by patients' medical records and self-report. Multilevel logistic, linear and Poisson regression examined how ADEs, HRQOL and A&E visits varied by PIP after adjusting for patient and practice level covariates: socioeconomic status, co-morbidity, number of drug classes and adherence.

Results: The overall prevalence of PIP was 42% (n = 377). Patients with ≥2 PIP indicators were twice as likely to have an ADE (adjusted OR 2.21; 95% CI 1.02, 4.83, P < 0.05), have a significantly lower mean HRQOL utility (adjusted coefficient -0.09, SE 0.02, P < 0.001) and nearly a two-fold increased risk in the expected rate of A&E visits (adjusted IRR 1.85; 95% CI 1.32, 2.58, P < 0.001). The number of drug classes and adherence were also significantly associated with these same adverse health outcomes.

Conclusions: Reducing PIP in primary care may help lower the burden of ADEs, its associated health care use and costs and enhance quality of life in older patients.