Acculturation and sleep among a multiethnic sample of women: the Study of Women's Health Across the Nation (SWAN).

STUDY OBJECTIVES

Mexican immigrants to the United States report longer sleep duration and fewer sleep complaints than their US-born counterparts. To investigate whether this effect extends to other immigrant groups, we examined whether the prevalence of self-reported sleep complaints is higher among US-born Hispanic/Latina, Chinese, and Japanese immigrant women compared to their first-generation immigrant ethnic counterparts as well as to US-born whites. We examined whether these associations persisted after adjusting for sociodemographic and health characteristics and whether acculturation mediated the effects.

DESIGN

Cross-sectional observational study.

SETTING

Multisite study in Oakland, CA; Los Angeles, CA; and Newark, NJ.

PARTICIPANTS

Hispanic/Latina (n = 196), Chinese (n = 228), Japanese (n = 271) and non-Hispanic white (n = 485) women (mean age = 46 y, range 42-52 y) participating in the Study of Women's Health Across the Nation (SWAN); 410 or 59.0% of the nonwhites were first-generation immigrants.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Questionnaires were used to assess sleep complaints, race/ethnicity, immigrant status, language acculturation (use of English language), and sociodemographic and health variables. Approximately 25% of first-generation immigrant women reported sleep complaints compared to 37% of those who were US-born nonwhites and 42% of US-born whites. Multivariable adjusted logistic regression analyses showed that US-born nonwhites had higher odds of reporting any sleep complaints (odds ratio = 2.1, 95% confidence interval [CI] 1.5-3.0), compared to first-generation immigrants. Women with higher levels of language acculturation had greater odds of reporting any sleep complaint compared to those with less language acculturation. Adjustment for language acculturation mediated 40.4% (95% CI 28.5-69.8) of the association between immigrant status and any sleep complaint. When results were stratified by race/ethnicity, significant mediation effects of acculturation were only found for Hispanic/Latina and Japanese women, but not for Chinese women.

CONCLUSION

US-born Hispanic/Latina, Chinese, and Japanese immigrants were more likely to report sleep complaints than their first-generation ethnic counterparts, a finding largely explained by language acculturation and unmeasured factors associated with language acculturation.