An observational study of once-daily modified-release methylphenidate in ADHD: quality of life, satisfaction with treatment and adherence

Abstract

Attention deficit hyperactivity disorder (ADHD) impacts significantly on the quality of life (QoL) of patients and their families. Choice of therapy is increasingly influenced by treatment satisfaction and patient preference, with once-daily modified-release methylphenidate (MPH-MR) formulations offering clear benefits compared with immediate-release (IR) dosage forms. The effects of MPH-MR on QoL in ADHD have not been widely investigated and need more clarity in practice. The open-label OBSEER study evaluated the effectiveness and tolerability of Equasym XL(®), a MPH-MR formulation, in routine practice. Children and adolescents (aged 6-17 years) with ADHD and attending school were included if Equasym XL(®) treatment was planned by the treating physician. Physicians, parents and patients completed questionnaires assessing QoL (KINDL; parent, child or adolescent versions), satisfaction with medication, adherence and treatment tolerability at baseline (Visit 1), 1-3 weeks (Visit 2) and 6-12 weeks (Visit 3) over a maximum 3-month observation period. Data from 822 consecutively referred patients were analysed. QoL and medication satisfaction increased from Visit 1 to Visit 3, with both patients and parents rating therapy with Equasym XL(®) as better than previous drug therapy. KINDL total score effect sizes were 0.67 (parents' ratings), 0.52 (children's ratings) and 0.51 (adolescents' ratings; all p < 0.001). All KINDL subscores also increased: both parents and patients had the greatest improvement for school. Adherence to Equasym XL(®) was frequently rated as superior to prior treatment, particularly compared with MPH-IR repeated dosing. Treatment was generally well tolerated; approximately 3% of the patients discontinued treatment due to adverse events. Equasym XL(®) improved QoL compared with prior therapy, and resulted in good medication satisfaction and adherence in drug-naïve and previously treated patients.

Fig. 1

Quality of life total scores (KINDL questionnaire, parent ratings) during the study, by prior treatment. All comparisons are significant at p ≤ 0.001 (two-tailed test between KINDL total score at Visit 1 versus total score at Visit 3). IR immediate release, MPH methylphenidate, MR modified release

Fig. 2

a Mean ratings of adherence to treatment with Equasym XL^®, as assessed by attending physicians, at last visit. n = 773; 49 missing values. 1 very good, 6 fail. b Adherence to treatment with Equasym XL^® compared with adherence to prior treatment. n = 553; 61 missing values. IR immediate release, MPH methylphenidate, MR modified release

Fig. 3

Physician-rated global assessment of tolerability at Visit 3, by prior treatment. n = 734; 88 missing values. IR immediate release, MPH methylphenidate, MR modified release