Prevalence and predictors of potentially inappropriate prescribing using codified STOPP-START and Beers criteria: a retrospective cohort study in Ontario's older population

Objectives

To quantify potentially inappropriate prescribing (PIP) and assess the association between patient characteristics and PIP using previously coded STOPP-START and Beers criteria in Ontario's older population.

Study Design and Setting

An established subset of the 2014 STOPP-START and 2015 Beers criteria applicable to health administrative data were used to identify instances of PIP in health administrative data. Associations between the patient characteristics and PIP were examined using multivariable logistic regression. Using Ontario's large health administrative databases, which comprise individual-level, linked information on medication dispensation, physician services use, emergency room visits, hospitalizations, mortality, and sociodemographic data, a cohort including all patients ≥65 years who were issued at least 1 prescription between April 2003 and March 2017 (N = 2,937,927) was formed.

Results

From a total of 2,937,927 patients, 2,220,641 (75.6%) patients were identified with at least 1 PIP using the STOPP-START criteria. Using the Beers criteria, 1,505,243 (51.2%) patients were identified. The most common PIP identified by the STOPP-START criteria was the lack of pneumococcal vaccine to be given at least once after age 65 years according to national guidelines (75.9% of patients). Patient characteristics that were found to be strongly associated with PIP identified by both STOPP-START and Beers criteria were age, female sex, long-term care resident, lack of MedsCheck prior to index date, and frailty, among others.

Conclusion

Applying coding for identifying PIP in health administrative data is a promising approach to screen for PIP at the population level in an impactful and cost-effective manner. This approach will allow investigators to identify areas for intervention in terms of PIP in a population.

Plain Language Summary

We studied medication use in Ontario adults aged 65+ years to identify both potentially harmful or unnecessary prescriptions and important medications that were missing, using established prescribing guidelines. Among nearly 3 million Ontarians, 75% were prescribed at least 1 potentially inappropriate medication with the pneumococcal vaccine (76% of cases) being the most commonly missing medication. Those most at risk included adults over 85 years of age, women, long-term care residents, and people with frailty or no prior medication review. These findings show how health data can efficiently identify prescribing gaps, helping target interventions like improved vaccine programs or medication reviews to enhance safety for older adults.