ADHD in adults is commonly associated with comorbid psychiatric disorders including a high prevalence of anxiety and depression in women, and substance use, antisocial and conduct disorders in men.
The aim of this study was to evaluate the burden of illness and healthcare resource utilisation in adult, non-psychotic, psychiatric outpatients with ADHD. To put the disease burden in perspective, patients with ADHD were compared with outpatients without ADHD. The extent of healthcare resource utilisation by these patients was also examined.
This was an observational study in which unselected routine patients from general psychiatric outpatient settings were screened. The study was conducted in Austria, Belgium, Denmark, Germany, The Netherlands, Spain, Sweden and the UK. Patients aged 18–65 years (enrolled N=2284; completed N=1986) were enrolled from different outpatient settings providing general psychiatric care. Initial ADHD screening was carried out using the Adult ADHD Self-Report Scale (ASRS) and the Provisional Diagnostic Instrument-4 (PDI-4), and further confirmed by the Diagnostic Interview for ADHD (DIVA). Other data, such as incidence of comorbid conditions, quality of general functioning and healthcare resource utilisation (medication use, doctors’ visits, hospitalisation in the previous 6 months) were captured. Burden of illness was evaluated using the Clinical Global Impressions of Severity (CGI-S) scale, the Sheehan Disability Scale (SDS), and the EuroQol-5 Dimensions questionnaire.
Results show that the prevalence of ADHD in psychiatric patients was 17.4%. The most prevalent comorbidities in patients with ADHD were depression (43%) and anxiety (36.4%). Rates of substance use disorders were substantially higher in patients with ADHD compared with patients without ADHD (substance abuse 9.2% vs 3.4%; alcohol abuse 10.3% vs 5.2%). Also, patients diagnosed with ADHD had higher levels of functional impairment, as reflected by higher scores for CGI-S (3.8 vs 3.3) and SDS (18.9 vs 11.6) and higher percentages of debt (35.5% vs 24.3%) and criminality (13.8% vs 6.1%). Overall, resource utilisation was comparable between the two groups.
In summary, patients with ADHD had a high percentage of comorbidities, and were more likely to be moderately to severely ill (CGI-S scores), and have higher disability (SDS) scores and lower quality of life (EQ-5D) scores compared with patients without an ADHD diagnosis. Nonetheless, healthcare resource utilisation was similar relative to controls.
Karlsdotter K, Bushe C, Hakkaart L, et al. Burden of illness and health care resource utilization in adult psychiatric outpatients with attention-deficit/hyperactivity disorder in Europe. Curr Med Res Opin 2016; 32: 1547-1556.