April 2024 Journal Club – ADHD Pharmacotherapy Showed a Signal for 2year Mortality Reduction But is Likely Healthy User Bias

This headline grabbing paper recently came through, and also pops up on the wellknown point of care decision support resource, UpToDate when searching ADHD treatment. It reports on an observational study done with Swedish registry data evaluating the impact of treatment for ADHD on mortality in those aged 6-64. The authors reported a protective effect in overall mortality of 0.79 (0.70-0.88), which subgroup analysis suggests was driven by accidental poisoning, i.e., overdose, in men. The authors made efforts to adjust for confounders in the data but the bias introduced when comparing those treated versus not is a notorious cause of bias (Schneeweiss et al 2007) that is very possibly in effect here. The authors suggest that because of this, and because of multiple comparisons made, their findings should be considered exploratory.