Objective: To examine the course of adolescent major depressive disorder (M
DD) by comparing rates of mood and non-mood disorders between age 19 and 24
years in participants with a history of adolescent MDD versus participants
with adolescent adjustment disorder with depressed mood, nonaffective diso
rder, and no disorder. Method: Participants from a large community sample w
ho had been interviewed twice during adolescence completed a third intervie
w assessing Axis I psychopathology and antisocial and borderline personalit
y disorders after their 24th birthday: 261 participants with MDD, 73 with a
djustment disorder, 133 with nonaffective disorder, and 272 with no disorde
r through age 18. Results: MDD in young adulthood was significantly more co
mmon in the adolescent MDD group than the nonaffective and no disorder grou
ps (average annual rate of MDD = 9.0%, 5.6%, and 3.7%, respectively). Adole
scents with MDD also had a high rate of nonaffective disorders in young adu
lthood (annual nonaffective disorder rate = 6.6%) but did not differ from a
dolescents with nonaffective disorder (7.2%). Prevalence rates of dysthymia
and bipolar disorder were low (<1%). Adolescents with adjustment disorder
exhibited similar rates of MDD and nonaffective disorders in young adulthoo
d as adolescents with MDD. Conclusions: This study documents the significan
t continuity of MDD from adolescence to young adulthood. Public health impl
ications of the findings are discussed.