Impact of Potentially Inappropriate Prescribing on Adverse Drug Events, Health Related Quality of Life and Emergency Hospital Attendance in Older People Attending General Practice: A Prospective Cohort Study.

Emma Wallace, RCSI Dublin
Ronald McDowell, Royal College of Surgeons in Ireland
Kathleen Bennett, RCSI
Tom Fahey, Royal College of Surgeons in Ireland
Susan M. Smith, Royal College of Surgeons in Ireland

Document Type Article

The original article is available at


BACKGROUND: Potentially inappropriate prescribing (PIP) describes medications where risk generally outweighs benefit for older people. Cross-sectional studies suggest an association between PIP and poorer health outcomes but there is a paucity of prospective cohort studies. This study investigates the longitudinal association of PIP with adverse drug events (ADEs), health related quality of life, and accident & emergency visits.

METHODS: Study design: Two-year (2010-2012) prospective cohort study (n = 904, ≥70 years, community-dwelling) with linked pharmacy dispensing data.

EXPOSURE: Baseline PIP: Screening Tool for Older Persons potentially Inappropriate Prescriptions (STOPP) and Beers 2012 applied 12 months prior.

STUDY OUTCOMES: ADEs (patient interview), health related quality of life (EQ-5D-3L: patient questionnaire), and accident & emergency visits (general practice medical record review).

STATISTICAL ANALYSIS: Descriptive statistics: Poisson (incidence rate ratio [95% confidence interval [CI]], linear regression models [regression coefficient [95% CI]], and logistic [odds ratio [OR] [95% CI]).

RESULTS: Of 791 participants eligible for follow-up, 673 (85%) returned a questionnaire and 605 (77%) also completed an ADE interview. Baseline STOPP PIP prevalence was 40% and 445 (74%) patients reported ≥1 ADE at follow-up. In multivariable analysis, ≥2 STOPP PIP was associated with ADEs (adjusted incidence rate ratio: 1.29 [95% CI 1.03, 1.85; p = .03]; poorer health related quality of life [adjusted regression coefficient: -0.11 [95% CI -0.16, -0.06; p < .001]]; and, ≥1 accident & emergency visit [adjusted OR: 1.85 [95% CI 1.06, 3.24; p = .03]]). Baseline Beers 2012 prevalence was 26% and there was no association with adverse health outcomes in multivariable analysis.

CONCLUSIONS: Older community-dwelling people, prescribed ≥2 STOPP PIP are more likely to report ADEs, poorer health related quality of life and attend the accident & emergency department over 2-year follow-up.