Family conflict in childhood: a predictor of later insomnia.

STUDY OBJECTIVES

To examine the association between childhood exposure to family conflict and insomnia at 18 years of age.

DESIGN

Longitudinal prospective data on an entire birth cohort were obtained. Parents completed the Conflict subscale of the Moos Family Environment Scale when the study members were 7, 9, 13, and 15 years of age. Insomnia was examined in a standardized interview when the participants were aged 18 years.

SETTING

Participants were born in Dunedin, New Zealand, and were interviewed at this location.

PATIENTS OR PARTICIPANTS

One thousand thirty-seven children born between April 1, 1972, and March 31, 1973, enrolled in the study (52% male). At age 18 years, 993 (97% of living cohort members) provided data.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

The mean level of family conflict at age 7 to 15 years predicted insomnia at 18 years after controlling for sex, socioeconomic status, sleep problems at 9 years, and self-reported health (odds ratio [95% confidence interval] = 1.42 [1.17-1.73], p < .001). There was a dose-response relationship, whereby the more assessments at which families scored in the top 25% for conflict, the greater the young person's likelihood of developing insomnia at age 18 years. This association was present even after controlling for depression at 18 years.

CONCLUSIONS

This study demonstrates a modest but robust longitudinal link between family conflict during childhood and insomnia experienced at 18 years of age. Future work needs to replicate this finding in different populations and to elucidate the mechanisms underlying this association.