Weissman (2005)

Question 1

Aim

Answer 1

To study the potential genetic nature of Major Depressive Disorder (MDD)

Question 2

Participants

Answer 2

• Longitudinal family study with a sample of 161 grandchildren and their parents and grandparents

Question 3

Method

Answer 3

• Took place over 20 years
• Original sample of depressed patients (now, the grandparents) was selected from an outpatient clinic with a specialization in the treatment of mood disorders
• Non-depressed participants were selected from the same local community
• Original sample of parents and children were interviewed four times during this period
• Data was collected from clinicians, blind to past diagnosis of depression or to data collected in previous interviews

Question 4

Results

Answer 4

• High rates of psychiatric disorders in the grandchildren with two generations of major depression
• Children had an increased risk of any disorder if depression was observed in both the grandparents and the parents, compared to children where their parents were not depressed
• Severity of a parent’s depression was correlated with an increased rate of a mood disorder in the children
• If a parent was depressed but there was no history of depression in the grandparents, there was no significant effect of parental depression on the grandchildren