Cannabis misuse linked to ADHD symptoms but not broader cognitive deficits in 1,008 adults

After controlling for age, income, sex, alcohol, and tobacco use, cannabis use severity predicted greater hyperactive-impulsive and inattentive ADHD symptom endorsement in 1,008 adults, but was not associated with other neurocognitive measures. In young adults (n=371), cannabis severity was linked to digit span forward and hyperactive symptoms. In high-risk users (n=161), associations extended to delay discounting and impulsive ADHD symptoms. Age of first cannabis use was not associated with any cognitive outcome.

Dimensional design with 1,008 community adults (mean age 38.5, 56% female) assessed for cannabis involvement, ADHD symptoms, and neurocognitive performance using validated measures and hierarchical multiple regression.

The large sample resolves inconsistencies from smaller studies: cannabis misuse appears specifically linked to ADHD-type symptoms rather than broad cognitive decline. The null finding for age of first use challenges the "earlier is worse" narrative.

The specific ADHD-symptom link (not general cognition) raises two possibilities: cannabis use worsens attention regulation specifically, or people with pre-existing attention difficulties are more likely to develop problematic cannabis use. Either way, ADHD screening in cannabis users may be clinically valuable.

Cross-sectional (cannot determine directionality); community sample may underrepresent heavy users; ADHD symptoms self-reported, not clinically diagnosed; cannabis involvement measured dimensionally, not by product type or potency.