Klein et al (2001)

Uses: kinship study, genetics

AIM: To investigate the continuities and discontinuities in children and adolescents and MDD in adults in a family.

METHOD: Observational study

PROCEDURE:

268 adolescents with history of MDD, 110 adolescents with a history of non-mood disorders but no history of MDD through age 18 years, and 291 adolescents with no history of psychopathology through age 18 years. Psychopathology in their 2202 first-degree relatives was assessed with semi-structured direct and family history interviews, and best estimate diagnoses were derived with the use of all available data.

RESULTS:

 The relatives of adolescents with MDD exhibited significantly elevated rates of MDD, dysthymia, and alcohol abuse or dependence, but no anxiety disorders, drugs abuse or dependence or antisocial and borderline personality disorder. In contrast, anxiety, substance use, and disruptive behavior disorders in adolescents were not associated with elevated rates of MDD in relatives, However, the relatives of probands with anxiety and substance use disorder exhibited elevated rates of anxiety and substance use disorders, respectively.

CONCLUSIONS:

The result provided evidence of the familial aggregation in adolescent MDD, and also indicates that there is a considerable specificity in the pattern of familial transmission. In addition, we found preliminary evidence of the familial aggregation of adolescent anxiety and substance use disorders.

EVALUATION:

Sampling bias

Reductionist

Bottom up study

Also tests other problems, not just MDD

Klein DN, Lewinsohn PM, Seeley JR, Rohde P. A Family Study of Major Depressive Disorder in a Community Sample of Adolescents. Arch Gen Psychiatry. 2001;58(1):13–20. doi:10.1001/archpsyc.58.1.13