3. Results

3.1 Study Population

The number of patients treated for diabetes included in this study ranged from 27,845 in 2012 to 24,809 in 2016. The percentage of people with diabetes out of the total population was around 8-9% throughout the study period. Among the people with diabetes, around 14% were 45-54 years, around 25% were 55-64 years, and around 61% were 65 years or older. From 2012 to 2016, the percentage in the oldest age group slightly increased from 59.1% to 61.5% (Table 1).

3.2 Trends of polypharmacy in people with diabetes

Overall, the prevalence of polypharmacy increased from 56.5% (95% Confidence Interval [CI] 55.9-57.1) in 2012 to 58.2% (95% CI: 57.6-58.8) in 2016 (p-value for trend <0.001), with the highest prevalence in 2015 of 58.8% (95% CI: 58.2-59.3) (Figure 2). In the oldest age group, the highest prevalence was 66.2% in 2016 (95% CI: 65.5-67.0). In the same year, the prevalence was 50.3% (95% CI: 49.0-51.5) in the 55-64 years old, and 36.9% (95% CI: 35.3-38.5) in the 45-54 years old (Figure 2, Appendix Table 2). The absolute increase over the study period was 1.0% in the ≥65 years old, 2.0% in the 55-64 years old, and 1.4% in the 45-54 years old (p-values for linear trend for all age groups <0.001).

3.3 Trends in PIM in older people with diabetes and polypharmacy

In patients of 65 years and older with polypharmacy, the percentage with at least one PIM according to the 24 Beers criteria decreased from 28.0% in 2012 to 24.9% in 2016 (p-value for linear trend <0.001). The majority received one PIM (21-24%) and the highest number of PIMs was five (Table 2). The highest prevalence was observed for long-term high-dose use of proton-pump-inhibitors (PPI) (17-18%), for benzodiazepines (9-10%), for strong opioids without laxatives (7-8%), and for tricyclic antidepressants (TCAs) (6%) (Table 3).
At individual PIM level, also looking at the additional PROMPT criteria, absolute increases of at least 0.1% during the study period were seen for the use of strong opioids without laxatives (0.9%), TCAs (0.6%), long-term high-dose use of PPIs (0.5%), and sliding scale insulins (0.2%). Meanwhile absolute decreases of at least 0.1% were seen for the use of benzodiazepines (-1.7%), dipyridamole (-0.8%), long-acting sulfonylureas (-0.7%), long-term corticosteroids without biphosponates (-0.7%), high-dose digoxin (-0.4%), first generation antihistamines (-0.4%), nonsteroidal anti-inflammatory drugs (NSAIDs) without PPI or misoprostol (-0.4%), high-dose acetylsalicylic acid (-0.2%), and antispasmodics (-0.2%) (Table 3).

3.4 Trends in PIM in middle-aged people with diabetes and polypharmacy

In middle-aged patients with polypharmacy, the percentage with at least one PIM from the 13 PROMPT criteria increased gradually from 36.9% in 2012 to 39% in 2015. In 2016, the percentage decreased to 37.8% (p-value for quadratic trend <0.05). The majority received one PIM (27-30%), and the highest number of PIMs was five (Table 2). The highest prevalences were seen for the use of long-term high-dose PPI (22-23%), long-term benzodiazepines (11%), and strong opioids without laxatives (9-10%) (Table 3).
At individual PIM level, absolute increases during the study period were seen for long-term high-dose use of PPIs (0.7%), strong opioids without laxatives (0.6%), long-term corticosteroids without biphosponate (0.3%), long-term non-benzodiazepines (0.2%). Conversely, NSAIDs long-term without PPIs or misoprostol (0.4%), long-term benzodiazepines (0.4%), long-acting sulfonylureas (-0.2%), dipyridamole monotherapy (-0.2%), stimulant laxative no long-term, except with opioid (-0.2%) showed absolute decreases in prevalence (Table 3).