Potentially inappropriate prescribing to older patients in primary care in the Netherlands: a retrospective longitudinal study

Background: potentially inappropriate prescribing (PIP) is associated with adverse health effects in older patients. PIP comprises prescription of potentially inappropriate medications (PIMs) and potential prescribing omissions (PPOs). Objective: to estimate the prevalence of PIMs and PPOs among older patients in primary care. Design: retrospective longitudinal study. Setting: routinely collected data of 182,000 patients of 49 general practitioners (GPs) gathered in the GPs' database of the Academic Medical Center of Amsterdam, the Netherlands. Subjects: in each studied year, all patients who were aged 65 years and older at 1st January. Methods: the prevalence of patients with at least one PIM and patients with at least one PPO was measured in 8 subsequent years (2007-14) by application of the Screening Tool of Older Persons potentially inappropriate Prescriptions (STOPP)/Screening Tool to Alert doctors to Right Treatment (START) criteria. Multivariate logistic regression was used to evaluate trends in the prevalence of PIMs and PPOs over the years. Results: on average, 4,537 patients were included per investigated year. The mean prevalence of = 1 PIM was 34.7% (range 34.0-35.6%) and of = 1 PPO 84.8% (range 77.4-90.6%). Examples were the prescription of salicylates without a proper indication and the absence of a therapeutically indicated vitamin D prescription. The prevalence of = 1 PPOs showed a statistically significant decrease over the investigated years (OR 0.87, P < 0.001), whereas the prevalence of PIMs did not change significantly. Conclusions: this study underscores the need for more attention to medication prescribing to older patients. The prevalence of PIP among older patients in primary care is substantial and the prevalence of PIMs did not decrease over time.