Exploratory analysis of early treatment discontinuation and clinical outcomes of patients with attention-deficit/hyperactivity disorder

Treatment of ADHD in adults - prevalence of discontinuation and associated factors - results from a cross-sectional analysis of Danish register data

BACKGROUND

A growing number of adults are receiving pharmacological treatment for ADHD but a sizable proportion also discontinues or have gaps in treatment. The primary aims of this study were to identify how many patients treated for ADHD in adulthood, have at least one event of discontinuation in treatment and to identify possible associated variables.

METHODS

Within the Danish population aged 18-60 years on the 1st of January 2013, we identified the number of individuals who had been prescribed ADHD-medication at least once during the 1st of January 2002-31st of December 2013 using Danish register data. Among those who filed more than one prescription, treatment discontinuation was defined as having more than 211 days between two prescriptions. In crude and adjusted logistic regression analysis, we explored potential associations to discontinuation for variables such as gender and age at treatment initiation.

RESULTS

In a population, if N = 3,165,844 individuals, n = 42,892 had received at least one prescription for ADHD medication. Among those with more than one prescription (N = 38,289), 29.4% had discontinued their treatment at least once, according to our definition of treatment discontinuation. ADHD treatment discontinuation was associated with being male, unemployment, lower educational attainment, receiving incapacity benefits and younger age at treatment initiation (p < 0.001).

CONCLUSIONS

A large proportion of individuals treated for ADHD had at least one discontinuation of treatment according to our definition. Although the present study does not allow for investigating the direction of these effects, nor whether some patients later resumed treatment, having at least one discontinuation was associated with a range of variables relating to e.g. age and gender, and provides an emerging profile for clinicians of patients more likely to discontinue.

Clinical Impact of Not Achieving Recommended Dose on Duration of Atomoxetine Treatment in Adults with Attention-Deficit/Hyperactivity Disorder

Aim

To compare atomoxetine (ATX) length of therapy (LoT) among adults with ADHD who reached the recommended dose of 80 mg/day (ATX ≥ 80) versus those who did not (ATX < 80) analyzed separately in patients prescribed ATX as monotherapy (mono) and in combination with other ADHD medications (combo).

Methods

This was a retrospective observational cohort study of the Truven Health Marketscan Commercial Claims Database from January 1, 2006–September 30, 2013, with a 6‐month preindex period free of ATX (1st ATX claim as index event) and a 1‐year follow‐up. LoT during follow‐up was calculated using prescription claim fill dates and included all days with medication on hand regardless of treatment gaps.

Results

Only 45.0% of the 36,076 mono and 77.9% of the 1548 combo patients reached an ATX dose of ≥80 mg/day in 1‐year follow‐up. When patients filled at least one 80 mg prescription, their total days of therapy over the course of a year were significantly greater than if they did not (mono: 159.3 vs. 65.6 days; combo: 237.4 vs. 172.0; P < 0.0001). Across all timepoints examined (Day 14, 30, 60, 90, 210) for mono and combo, ATX ≥ 80 versus ATX < 80 patients had greater mean doses (P < 0.0001). Combo patients had longer ATX LoT than mono patients regardless if they reached 80 mg or not (P < 0.0001), but mono patients LoT was 93.8 days longer for ATX ≥ 80 versus ATX < 80 patients compared to 65.5 days for combo patients. Of patients reaching 80 mg/day, 71.7% of mono and 62.8% of combo patients did so by Day 30. For mono ATX ≥ 80 and ATX < 80 patients, LoT was significantly (P < 0.0001) less in previously treated patients compared to naive patients.

Conclusion

Ensuring adult ADHD patients are treated with ATX at a target dose of 80 mg/day is an important clinical consideration for maximizing patient days on therapy, which can be important for treatment optimization.