Familial clustering of depression could be due to combinations of:
(1) genetic abnormality affecting brain chemistry
(2) learned behaviors
Features of familial depression:
(1) higher Family Loading Score of Depression (FLSD)
(2) early onset, especially during childhood
(3) recurrent depression
(4) alcohol abuse or other ways of self-medication
(5) comorbid psychiatric disorders such as anxiety, especially in females
Significance:
(1) Diagnosis of major depression in a child should prompt a more complete family history.
(2) A family history of depression should prompt a screen for substance abuse.
(3) Identification of depression in several family members should prompt a screen of other family members.
Limitations:
• A patient with no family information or only small numbers of first-degree relatives may not be recognized.
• The presence of step parents and step siblings may introduce problems.
