A randomized-withdrawal trial asks whether benefits persist when established treatment continues rather than stops. It does not answer the same question as a trial enrolling previously untreated patients. That distinction is central to a 2014 lisdexamfetamine report on quality of life and functioning.
Selection occurred before randomization
Children and adolescents aged 6–17 first received at least 26 weeks of open-label oral lisdexamfetamine, with dose optimization between 30 and 70 mg/day. The open-label full analysis set contained 262 participants. Many came from an earlier European trial, creating cohort overlap with previous publications.
Only 153 entered the randomized-withdrawal phase: 76 continued their optimized dose and 77 switched to placebo for up to six weeks. The study therefore compared selected participants who had already tolerated and continued treatment, rather than an unselected population beginning amphetamine therapy.
What happened to parent-rated quality of life?
Parents completed CHIP-CE and functional-impairment questionnaires. During withdrawal, significant between-group differences favored continued treatment in the Achievement, Risk Avoidance and Satisfaction domains. The reported effect sizes were 0.696, 0.829 and 0.636, respectively.
The findings were not uniform across every domain and subdomain. Within Resilience and Comfort, significant group differences were limited to particular subdomains. A favorable result in selected domains does not demonstrate preservation of every aspect of health or daily life.
The endpoint was not six complete weeks for everyone
Only 57 continued-treatment participants and 16 placebo participants completed the randomized-withdrawal period. Endpoint included the last valid visit or early termination. Describing all 153 as completing six weeks would substantially misstate follow-up.
Withdrawal after a period of successful treatment is also different from receiving placebo without prior treatment. The design addresses maintenance in an enriched population; it cannot independently identify the optimal starting medicine or predict outcomes for initial nonresponders.
How strong were the statistical claims?
These quality-of-life and functional outcomes were secondary objectives. The reported p values were nominal and not corrected for multiple comparisons. The positive results should therefore retain their exploratory or descriptive qualification across the many domains examined.
The open-label improvements before randomization are less causally secure than the randomized comparison. Expectations, time and selection can contribute during a period without a control group.
Practical interpretation
The historical evidence supports maintenance of selected parent-rated benefits among children and adolescents who reached randomization after prolonged treatment. It does not establish a universal need for indefinite therapy, a safe stopping schedule or individual driving capacity. Those questions were not tested, and the report should not be treated as current prescribing advice.
Scientific source
Banaschewski T, Johnson M, Lecendreux M, et al. Health-Related Quality of Life and Functional Outcomes from a Randomized-Withdrawal Study of Long-Term Lisdexamfetamine Dimesylate Treatment in Children and Adolescents with Attention-Deficit/Hyperactivity Disorder. CNS Drugs. 2014;28:1191–1203. doi:10.1007/s40263-014-0193-z. Original commentary on the supplied paper.
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