EClinicalMedicine. 2026 Aug 31;99:104182. doi: 10.1016/j.eclinm.2026.104182. eCollection 2026 Sep.
ABSTRACT
BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) may compromise adherence to pharmacotherapy in adults with type 2 diabetes, but the relationship is unknown. We investigated the association of ADHD and ADHD medication with antidiabetic medication adherence in multinational cohort data.
METHODS: Using a common analytical protocol and population-based databases from seven countries, we identified adults initiating non-insulin antidiabetic medication between 2010 and 2020. ADHD was identified by diagnosis or ADHD medication use. We used the proportion of days covered (PDC) to measure antidiabetic medication adherence and defined the primary outcome, poor adherence, as PDC <80% over 1-, 2-, and 5-year follow-up periods. Time-to-first-discontinuation was the secondary outcome. Country-specific estimates were obtained using logistic and Cox regression and pooled using random-effects meta-analyses.
FINDINGS: Among 3,643,197 individuals included, 1,871,870 (51.4%) were female and 88,339 (2.4%) had ADHD (76,973 [87.1%] received ADHD medication). Overall, ADHD was not associated with poor adherence to antidiabetic medication (1-, 2-, and 5-year pooled odds ratios [OR]: 1.01 [95% CI 0.90-1.14], 1.03 [0.91-1.17], and 1.12 [0.95-1.31]); country-specific estimates ranged from 0.79 to 1.32, 0.80 to 1.35, and 0.80 to 1.47 at 1, 2, and 5 years, respectively. Among males, ADHD was associated with poorer adherence (1.09 [95% CI 1.00-1.20], 1.12 [1.00-1.24], and 1.23 [1.11-1.37] at 1, 2, and 5 years). Similar results were found for discontinuation. Among individuals with ADHD, ADHD medication use was consistently associated with better adherence over 1-, 2-, and 5-year follow-up periods (e.g., 5-year pooled OR 0.45 [0.30-0.67]); associations were directionally consistent across countries.
INTERPRETATION: Among adults with type 2 diabetes, ADHD may not necessarily compromise antidiabetic medication adherence when appropriately managed in routine care. ADHD pharmacological treatment may support adherence among adults with comorbid ADHD and type 2 diabetes, although its causal effect requires further evaluation.
FUNDING: EU Horizon 2020 Research and Innovation Programme.
PMID:42724543 | PMC:PMC13559831 | DOI:10.1016/j.eclinm.2026.104182
