Abstract
Aims
This study assesses national trends and, sociodemographic and clinical factors associated with polypharmacy and potentially in appropriate prescribing among people with type 2 diabetes in Scotland from 2012 to 2022.
Methods
Retrospective cohort study using nationwide data from the Scottish Care Information – Diabetes database. Individuals aged ≥40 years with type 2 diabetes were included. Medication counts were based on unique medications dispensed per calendar year. Potentially inappropriate medications were based on the 2023 Beers criteria and applied to people aged over 65 years. A Poisson mixed-effects model with individual-level random intercepts assessed the relationship between number of drug classes dispensed and year, gender, age group, and socioeconomic status, Elixhauser comorbidity index and the hospital frailty risk score.
Results
387,338 people were included. The median number of medications dispensed per person was 9 (interquartile range 5-13). Adjusted medication counts were modestly higher in older people (rate ratio [RR] 1.06, 95% confidence interval [CI] 1.06-1.06 at age 80+ compared to 40-59), higher in females (1.14, 1.13-1.14), in more deprived areas (1.24, 1.23-1.24 in most deprived vs most affluent quintile) and in those with higher comorbidity (1.12, 1.12-1.13 in 4+ vs 0 comorbidities) but not with high frailty risk (1.00, 1.00-1.00). People over 65 were dispensed a median of 2 (IQR 1-3) potentially inappropriate medications. Potentially inappropriate medication showed a stronger association with comorbidity (1.24, 1.23-1.25) and a positive association with high frailty risk (1.24, 1.23-1.25).
Conclusions
The degree of polypharmacy highlights the need for regular formal medication reviews in this population.