An exploratory analysis of lisdexamfetamine trials described symptom-item patterns across age and sex. It did not establish a validated age- or sex-based rule for predicting individual treatment response.
Weisler and colleagues reanalyzed two four-week placebo-controlled trials, one in children aged 6–12 and another in adults aged 18–55. They examined individual ADHD Rating Scale IV items within age-by-sex subgroups.
A total score can conceal different combinations of inattention and hyperactivity or impulsivity. Item-level description asks which symptoms contribute to that total. It is a different question from whether a medicine improves the average total score.
Baseline item scores were generally numerically similar across the examined subgroups. Inattention items tended to be more severe than hyperactivity/impulsivity items among older children and adults. Endpoint item scores were numerically lower after active treatment across the subgroups.
These observations should retain the paper’s exploratory, qualitative status. Similar-looking profiles do not demonstrate statistical equivalence, and a numerical difference between demographic groups is not a proven treatment interaction.
The trials were not prospectively powered for these subgroup questions. Some groups, especially placebo subgroups, were small, producing substantial variability. Comparing age groups from separate studies also differs from following the same people as they age.
The analysis was industry funded and based on selected clinical samples. It does not show that age or sex should determine a person’s dose, that all symptoms improve equally, or that scale changes measure driving ability. Its value is a more detailed description of symptom presentation, with uncertainty preserved rather than hidden by an overall score.
See a placebo-controlled cognitive comparison in youth.
Analysis of individual items on the attention-deficit/hyperactivity disorder symptom rating scale in children and adults: the effects of age and sex in pivotal trials of lisdexamfetamine dimesylate. doi:10.2147/NDT.S47087.