Use of attention-deficit/hyperactivity disorder medication among older adults in Denmark

Knowledge on the use of attention-deficit/hyperactivity disorder (ADHD) medication among older adults is limited. We hypothesized that ADHD medication is used off-label in adults aged ≥50 years as part of palliative care in e.g. cancer patients. The aim of this study was to describe the use of ADHD medication among adults aged ≥50 years in Denmark.

Using the Danish health registries, we identified new users ≥50 years of ADHD medication during 2000-2012. We estimated the annual incidence of ADHD medication use and ADHD diagnoses. We described new users of ADHD medication according to co-medication, comorbidities and assessed the 1-year cumulative mortality rate. A posthoc analysis allowed us to include new users until 2015.

We identified 6690 new users of ADHD medication from 2000 to 2012. From 2000 to 2015 we observed an increase in the incidence of ADHD medication use from 12.5 to 30.3 per 100 000 person-years. However, the incidence rate decreased from 2010 to 2015. Throughout the study period, the incidence rate of ADHD diagnoses was low (overall prevalence among new users ≤2%). Opioids were the most frequent comedication used (used by 54%), while cancer was the most frequent diagnosis preceding treatment (prevalence of 52%). The 1-year cumulative mortality was 50%, primarily driven by patients with a preceding cancer diagnosis.

There was an increase in the incidence of ADHD medication use in adults aged ≥50 years from 2000-2010 and a decreasing incidence from 2010-2015. Our results suggest that ADHD medication is used off-label in older adults as part of palliative care.