In a population-based cohort study of more than 580,000 Finnish youths, attention-deficit/hyperactivity disorder diagnosis at any age was associated with poorer educational outcomes compared with no diagnosis; however, diagnosis during the early school years was associated with higher grade point averages, higher likelihood of academic-track education, and substantially lower school dropout risk compared with diagnosis closer to age 16 years. The findings suggest that timing of diagnosis may be a key factor in long-term educational trajectories.

Researchers analyzed national registry data from individuals born in Finland between 1990 and 1999 and followed them through age 20 years.

Attention-deficit/hyperactivity disorder (ADHD) diagnosis was defined by the first recorded clinical diagnosis or medication purchase between ages 4 and 20 years. Educational outcomes included grade point average (GPA) at approximately age 16 years, upper secondary education pathways (academic vs vocational), tertiary enrollment, and school dropout at age 20 years.

Among the cohort, 12,208 males (2.1%) and 3,753 females (0.7%) had an ADHD diagnosis. Mean age at diagnosis was 11 years for males and 14 years for females.

School Dropout Risk

Older age at diagnosis during the compulsory school years was associated with increased dropout risk.

• Among males, dropout probability increased from 9% at age 4 years to 30% at age 16 years

• Among females, it increased from 10% at age 6 years to 27% at age 13 years

Patients diagnosed toward the end of compulsory education had the highest risk of school dropout, with nearly one-third not completing or being enrolled in education by age 20 years.

In contrast, among patients diagnosed following compulsory education, older age at diagnosis was associated with higher academic enrollment and lower probability of school dropout.

Academic Performance

GPA was lower among patients with ADHD compared with those without a diagnosis; however, earlier diagnosis was associated with higher GPA.

Among males, GPA declined from approximately 7.1 at diagnosis at age 4 years to 6.5 at age 16 years. Among females, GPA declined from approximately 7.6 at age 6 years to 7.0 at age 12 years.

Educational Pathways

At age 20 years, patients with ADHD were more likely to complete vocational rather than academic upper secondary education. Earlier diagnosis was associated with a higher probability of completing an academic track.

• Among males, academic degree probability decreased from 21% at age 4 years to 5% at age 15 years

• Among females, it decreased from 31% at age 4 years to 12% at age 14 years

Enrollment in tertiary education remained below 11% and was lower than among peers without ADHD. The lowest rates, approximately 3%, were observed among males diagnosed at ages 14 to 17 years.

Patterns by Sex and Timing

Associations between age at diagnosis and educational outcomes were similar among males and females, although males with ADHD had poorer school performance in absolute terms, while females had larger relative differences compared with peers without ADHD. Diagnosis incidence peaked at age 8 years and again at ages 14 to 15 years among males, while incidence among females increased during adolescence.

Study Details

Regression models were adjusted for sociodemographic and family factors, including parental education and household income. Outcomes were derived from national education registers, and ADHD diagnoses were identified from health care and medication data.

Limitations

The researchers noted several limitations, including incomplete capture of diagnoses from private and primary health care before 2011, potential misclassification of age at diagnosis relative to symptom onset, and the inability to infer causality due to the observational design. GPA data were unavailable for a small proportion of patients who did not apply to upper secondary education, which may have led to conservative estimates.

“ADHD diagnosis during the first years of school was associated with better school performance, more academic track choices, and lower probability of school dropout,” wrote lead researcher Lotta Volotinen, MSc, of the Helsinki Institute for Demography and Population Health at the University of Helsinki in Finland, and colleagues.

Full disclosures can be found in the study.

Source: JAMA Psychiatry