Why Diagnose and Treat ADHD in Adults?

Eliciting preferences for continuing medication among adult patients and parents of children with attention-deficit hyperactivity disorder

BACKGROUND

Adherence to medication for attention-deficit hyperactivity disorder (ADHD) is less than optimal. Previous studies have primarily focused on qualitative assessment of factors that influence medication adherence.

OBJECTIVE

This study aimed to quantify the factors that influence patient and parent preferences for continuing ADHD medication.

METHOD

A discrete-choice experiment was conducted to investigate preferences. Adults, and parents of children, with ADHD were presented with eight hypothetical choice tasks of three options (Medication A, Medication B, No Medication) described by six attributes related to medication outcomes. Preferences were estimated using a mixed multinomial logit model.

RESULTS

Overall, respondents' preferences (n = 216) for continuing medication were negative (mean [β] = -1.426, p < .001); however, a significant heterogeneity in preferences was observed amongst respondents (standard deviation = 0.805, p < .001). Improvements in education, aggressive behaviour, social behaviour and family functioning, and side effects and stigma, influenced respondents' decision to continue taking medication. The respondents were willing to continue medication if they experienced positive effects, but side effects (even moderate) were the strongest concern for not continuing medication. While side effects were the most important factor for both adult patients and parents of children with ADHD, improvement in education was relatively more important for adults and improvement in aggressive behaviour, social behaviour and family functioning was relatively more important for parents of children with ADHD. Parents were more likely to not continue a medication with severe side effects even at the highest level of improvement in education.

CONCLUSIONS

Side effects are the most important factor that influenced preferences for continuing medication for both adults with ADHD, as well as parents of children with ADHD. While overall the respondents preferred not to take/give medication, discrete-choice experiment showed that the relative importance of factors that influenced continuation of medications was different for the two groups.

PATIENT AND PUBLIC INVOLVEMENT

Adults, and parents of children, with ADHD participated in this study by completing the online questionnaire. The questionnaire was based on findings of research in the literature, as well as earlier focus groups conducted with adults, and parents of children, with ADHD. The face validity of the questionnaire was determined by asking parents of children, and adults, with ADHD (n = 3) to complete the survey and participate in a short discussion on their understanding of the questions and their recommendations on improving the clarity of the survey.

Development of an innovative adult attention-deficit hyperactivity disorder clinic

Pharmacist-psychiatrist collaborative clinic models in specialty mental health clinics are limited, and there has been only 1 report of a clinic focused on adult attention-deficit hyperactivity disorder (ADHD). In this article, we describe the successful implementation of a pharmacist-psychiatrist collaborative practice agreement in an adult ADHD clinic at an academic medical center. Adult patients diagnosed with ADHD after a comprehensive assessment, including a full neuropsychological evaluation, were enrolled in the collaborative treatment clinic. The collaboration was a partnership between a psychiatry department and a school of pharmacy at a public university. We report the details of 58 patients and 774 patient encounters at the collaborative pharmacist-psychiatrist practice from March 2015 through June 2018. The visits were billed using traditional medical billing codes for follow-up visits. Pharmacist practice opportunities included psychiatric evaluation, medication management, counseling, and referral to auxiliary services. Challenges to the clinic's success included limited pharmacist time, prescriptive authority, and reimbursement for services from payors. A collaborative practice model targeted at adult ADHD patients may be a unique clinic setting for psychiatric pharmacists.

Safety and tolerability of flexible dosages of prolonged-release OROS methylphenidate in adults with attention-deficit/hyperactivity disorder

The osmotic release oral system (OROS) methylphenidate formulation is a prolonged-release medication for the treatment of attention-deficit/hyperactivity disorder (ADHD) in children, adolescents, and adults. We conducted a seven-week open-label extension of a double-blind study to assess the safety and tolerability of OROS methylphenidate in a flexible dose regimen (18-90 mg daily) for the treatment of adults diagnosed with ADHD (N =370). Medication was adjusted to optimize efficacy and tolerability for each patient. Adverse events, vital signs, and laboratory parameters were assessed. Most patients (337; 91%) completed the seven-week treatment and the final dispensed dose was 18 mg (8%), 36 mg (29%), 54 mg (34%), 72 mg (20%), or 90 mg (9%). Adverse events were reported in 253 (68%) patients and most were mild or moderate in severity; most frequently reported included headache (17%), decreased appetite (13%), and insomnia (11%). Adverse events were rarely serious (<1%; 2/370). Small mean increases in systolic and diastolic blood pressure (both 2.4 mmHg) and pulse (3.2 bpm) were observed. Body weight decreased slightly (-1.5 kg). The results provide additional support for the safety and tolerability of prolonged-release OROS methylphenidate in a flexible dose regimen (18-90 mg/day) for the treatment of adults with ADHD.