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Published on: August 2, 2017
An ecological analysis of sleep health across five African-origin populations spanning the epidemiologic transition
Candice Choo-Kang1, Stephanie J Crowley2, Sirimon Reutrakul3
1Public Health Sciences, Parkinson School of Health Sciences and Public Health, Loyola University Chicago, Maywood, Illinois, USA.
Background:
Sleep health is emerging as a public health priority due to its strong associations with several key domains of health. However, most of the existing literature are from studies located in high income settings and may not be representative of low-middle income settings. Leveraging the Modeling the Epidemiologic Transition Study, a study of cardiometabolic disease risk in five diverse African-origin populations, we explored differences in objectively measured sleep behavior across cohorts from Ghana, South Africa, Jamaica, Seychelles, and the United States.
Methods:
Data from 809 participants (35-55 years old, 63% women) from the 5 Modeling the Epidemiologic Transition Study research sites were included. Objectively-measured sleep, using actigraphy, was scored according to the criteria of Patel and colleagues. For those with at least 5 nights of valid data, ecological mean sleep onset time, wake-up time, sleep duration, wake after sleep onset, and sleep efficiency were examined.
Findings:
Adjusted models indicate that sleep onset was earlier in all sites when compared to US (p<.005). Sleep efficiency varied by locations, being lower in participants from Ghana, South Africa, and Jamaica when compared to United States (Ghana β: -3.7, South Africa: -5.8, Jamaica: -1.3, p<.05 for all) and higher in Seychelles when compared to United States (Seychelles β: 1.6; p=.02). Women presented with shorter sleep duration but with higher sleep efficiency.
Interpretation:
Sleep duration, timing (wake time, midsleep time and sleep onset), and efficiency differ by country and sex, likely driven by socio-economic settings. Understanding sleep patterns in different contexts is needed to make informed and culturally appropriate health recommendations.
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