The harmful impact of depression extends far beyond the individual sufferer to caregivers, friends and family members.  Children of people with depression are more likely to suffer from depression themselves.  This may be due to both inherited and environmental factors.

This new randomised controlled trial (RCT), published earlier this week in JAMA Psychiatry, set out to establish whether cognitive-behavioural prevention (CBP) can reduce the incidence of depression in children whose parents are (or have been) depressed.

Methods

The RCT was carried out at four different treatment centres in the US.

Participants

Children (aged 13-17 years old) were recruited who:

• had at least one parent or carer with depressive disorder
• were not currently being treated for depression
• had subsyndromal depressive symptoms, scoring ≥ 20 on CES-D (Center for Epidemiologic Studies Depression Scale), or a history of depressive disorder, in remission for at least 2 months

Regimens

33 sets of siblings were randomised, a total of 316 participants.  159 children were allocated to the CBP intervention, with 157 allocated to UC.

Cognitive-Behavioural Prevention:

• Emphasised cognitive restructuring and problem solving
• 90-minute sessions of mixed-sex, 3-10-participant
• 8-weekly acute sessions and 6-monthly continuation sessions

It’s not clear what the Usual Care regimen was.

Outcomes

Outcomes were measured at baseline, after the acute intervention (2 months), after the continuation (9 mo), 1 year after (21 mo) and 2 years later (33 mo).

• Depression onset rate
• CES-D, CDRS-R
• Sibling correlations were investigated
• NNTs were calculated

Results

• 

  Over the 33-month follow-up, 36.8% of adolescents receiving CBP had a depression onset vs 47.7% of youth in the UC group, corresponding to an NNT of 10 (95% CI, 5 to 2,624)

• There was some evidence that children whose parents were not depressed at the time of intake were more likely to benefit.  128 (45.4%) of parents had active depression at enrolment
• Differences in CES-D and CDRS-R were not statistically significant

Conclusions

The researchers concluded:

The CBP program showed significant sustained effects compared with UC in preventing the onset of depressive episodes in at-risk youth over a nearly 3-year period.

Important next steps will be to strengthen the CBP intervention to further enhance its preventive effects, improve intervention outcomes when parents are currently depressed, and conduct larger implementation trials to test the broader public health impact of the CBP program for preventing depression in youth.

Comments

• It’s not clear whether treatment allocation was concealed prior to recruitment
• It’s not clear how experienced the therapists were
• There was a lot of variation in attendance between centres in retaining participants and in the outcomes experienced by those participants
• Outcomes assessors were blinded to treatment group
• The confidence interval around the benefit was very wide, and close to the “line of no difference” (hence the large upper limit on the NNT)
• It should be noted that children of parents who were currently suffering a depressive episode did not appear to benefit from the intervention
• Although there is a risk of selection bias and some evidence of performance bias, it seems that this study shows promise for preventive interventions, particularly amongst children whose parents are not currently experiencing an active depressive episode

Link

Beardslee,, WR et al Prevention of Depression in At-Risk Adolescents: Longer-term Effects. JAMA Psychiatry. doi:10.1001/jamapsychiatry.2013.295