Objective:

Background:

ADHD is common in childhood and adolescence, but it persists into adulthood in most cases, even without a prior diagnosis.

Design/Methods:

A retrospective observational study was conducted, analyzing 42 patients between the ages of 16 and 65, who were evaluated between June 2022 and July 2024. Crude annual incidence rates, sex- and age-specific incidence rates, and rates standardized according to the 2022 National Population Census of Argentina (CNPA) were calculated, along with sociodemographic characteristics and results from self-administered questionnaires and neuropsychological tests.

Results:

The crude annual incidence rate of ADHD was 74.8 per 100,000 inhabitants/year (95% CI: 6.25-19.1), 65 per 100,000 in men (95% CI: 7.2-33.1), and 83 per 100,000 in women (95% CI: 3.4-17.2). The rate adjusted to the CNPA was 5.8 cases per 100,000 inhabitants/year. The mean age at diagnosis was 33.80 years (SD 13.22), with the most frequent subtype being inattentive (54.76%), followed by combined (35.71%) and hyperactive (4.76%). No significant sex differences were found among ADHD subtypes (p: 0.22). The majority of patients had incomplete university education (30.95%) and were employed (59.52%). The most common comorbidities were anxiety (90.48%) and depression (57.14%). Substance use affected 35.71% of patients, with marijuana being the predominant substance. Neuropsychological tests showed below-average Z-scores in IFS (-1.65, SD 1.23), TRAIL B (-1.43, SD 1.33), TRAIL A (-0.95, SD 1.3), PASAT 3 seconds (-1.29, SD 1.22), and IMO (-1.16, SD 0.84).

Conclusions:

This work represents the first incidence study of ADHD in Argentina and shows a low crude annual incidence rate and census-adjusted rate compared to other recent studies conducted in different populations.