Body size at birth and psychiatric disorders among adolescents: a clinical study of 310 under-age inpatient adolescents in Northern Finland.

BACKGROUND

Deviant birth measure is a risk factor for later somatic illness but also for later psychiatric disorders of the offspring. Only a few studies have examined the association of birth measures to later psychiatric disorders among adolescents. Studies on sex differences in these associations are scarce as well.

METHODS

The cases consisted of 508 adolescents (208 boys and 300 girls) aged 12-17 years, who were admitted to inpatient psychiatric hospitalization between 2001 and 2006. In addition, 478 healthy controls were derived from the Northern Finnish Birth Cohort 1986, born in approximately the same period and same area as the cases. Data of birth measures were collected from the National Birth Register for cases and from antenatal clinics for controls. Both cases and controls were interviewed using the Schedule for Affective Disorder and Schizophrenia for School-Age Children-Present and Lifetime (K-SADS-PL) to assess psychiatric disorders.

RESULTS

The adolescent patients were statistically significantly shorter and had higher ponderal index at birth compared to healthy controls. In addition, the age of the mothers at adolescent's birth was significantly younger in the patients than the controls. After controlling for various covariates, a 2.4-fold increased likelihood for internalizing disorders was seen among male adolescents with high ponderal index.

CONCLUSIONS

The association of birth measures to psychiatric disorders was confirmed in our study, particularly among male adolescents suffering from internalizing disorders. Further studies in larger adolescent samples are needed to confirm our findings and clear up the association of high ponderal index to specific psychiatric disorders.