Sleep Characteristics Among In-School Adolescents In South-Western Nigeria: Pattern, Determinants And Association With Cardio-Metabolic Risk Factors

Abstract

Problematic sleep is a major threat to the well-being of adolescents globally. However, little is known about the sleep health of adolescents in Africa. Thus, this study aimed to map studies on adolescent sleep health in Africa, determine the sleep characteristics of Nigerian adolescents in rural versus urban communities and the association between their sleep health and cardio- metabolic risk factors. We conducted a scoping review by searching five databases from the inception (beginning) of each database to June 2023 using Joanna Briggs Institute (JBI) methodology. Furthermore, a quantitative, cross-sectional study was conducted among adolescents aged 13-19 in six rural and six urban schools in Osun State, Nigeria. We used structured questionnaires to measure sleep duration and quality, daytime sleepiness, and sleep apnea risk and used actigraphs on a subset. We measured their anthropometry, blood pressure and blood sugar. A continuous cardiometabolic (CMR) score was calculated using z-scores of mean arterial pressure (MAP), body mass index (BMI), waist circumference (WC), and random blood glucose. The data obtained was analysed using Stata 15 and SAS software. The 31 studies (77% cross-sectional) included in the scoping review were mainly focused on sleep quantity and quality. Inadequate sleep duration during weekdays was common among adolescents, often compensated by longer weekend sleep durations. Additionally, the prevalence of poor sleep quality and sleep disorders, such as insomnia and sleep-disordered breathing, was high across various regions. Younger age was reported as protective of good sleep health, while gender disparities in adolescent sleep health were noted across regions. The use of electronic devices at bedtime was a major risk factor for sleep disturbances among urban-dwelling adolescents while poor sleeping conditions impaired sleep, especially among adolescents in rural communities and for those in lower social class. Among the 900 participants in the quantitative study, (51% rural; 59% female; average age (SD) = 15.1(1.4) years), the adjusted odds of having poor sleep quality vii (p = .008) and daytime sleepiness (p = .007) were 2-fold higher among urban compared to rural adolescents. Poorer sleep quality was associated with a higher CMR score (β=0.02), BMI z-score (β=0.04) and WC z-score (β=0.03) (all p<0.05). Lower sleep duration was associated with a higher CMR score (β=0.04), BMI z-score (β=0.11), and WC z-score (β=0.07) (all p<0.05). Risk of sleep apnea was associated with higher CMR score (β=0.08), MAP z-score (β=0.17) and WC z-score (β=0.14) (all p<0.05). Using actigraphy for 170 adolescents, shorter total sleep time and earlier wake times were seen on weekdays than weekends. In conclusion, adolescents in rural communities had better sleep than their urban counterparts. Urban adolescents have later bedtimes, earlier wake times and shorter time in bed and total sleep time than rural adolescents. Furthermore, poor sleep health was associated with higher CMR. Interventions aiming to improve the sleep characteristics of adolescents are crucial, especially for urban-dwelling adolescents and may be important for preventing cardiometabolic disease