Nutritional status, growth and sleep habits among Senegalese adolescent girls

Abstract

Objective: To study the relation between sleep habits, nutritional status, growth and maturation in a group of African adolescent girls. The main hypothesis to be tested was that sleep length could be an effective way to spare energy, and thus malnourished girls sleep longer than normal girls. Design: Three repeated yearly surveys (1997)(1998)(1999)) on a subsample of girls drawn from a larger study cohort on growth at adolescence. Setting: The Niakhar district in the central part of Senegal. Subject: In total, 40 girls were initially drawn. Missing girls were replaced at each round by girls having the same characteristics and belonging to the same cohort. Intervention: At each round, data on pubertal development (breast stages and occurrence of menarche), growth and nutritional status were collected. Adolescents wore an accelerometer for three or four consecutive nights and days at each round. Results: At the beginning of the survey, girls were 13.370.5 y old. They were under international reference values in weight and height. Their mean sleep duration was 8.570.9 h. Their puberty status did not influence their sleep habits; however, they slept more in March than in June, which was related to the seasonal change in daylight. There was a significant relation between body mass index and sleep habits: thinner girls slept a longer time and more quietly than the more corpulent girls. Conclusion: The nutritional status of these girls influenced their sleep habits: this may have been either a direct causal relation or a consequence of a protective attitude on the part of the mothers towards the frailer girls. Sponsorship: The R024 'Epidémiologie et Prévention' of the IRD (France) and the Nestlé Foundation.

Patterns of daily activity and time spent in bed of adult women and adolescent and preadolescent girls from a rural community in Senegal, West Africa

“…Interestingly, there was a negative association between time in bed and subcutaneous fat. We reported a similar finding previously in data on another group of girls (Benefice et al 2004). A first plausible explanation is that, in these marginally nourished girls, longer time in bed would improve recovery from a hard day's work and restore the energy balance.…”

“…Thus, this variable is not equivalent to sleep duration. However, when comparing findings concerning the present adolescent girls with those from another longitudinal study (Benefice et al 2004), we obtained extremely close results for bedtime (9:43 ± 0:40 pm in this study versus 9:57 ± 0:41 pm), time of awakening (6:31 ± 0:44 am in this study versus 6:38 ± 0:31 am) and time spent in bed (8:36 ± 1:00 h in this study versus 8:33 ± 0:54 h). For accelerometry counts during the day, reliability was acceptable (ICC=0.73) according to criteria found in the literature (Janz et al 1995).…”

“…Similarly, for a given age, thinner girls slept longer and more quietly than more robust girls (Benefice et al 2004). …”

Determinants and impact of sleep duration in children and adolescents: data of the Kiel Obesity Prevention Study

“…Whereas Benefice et al (2004) could not find an association between sleep and physical activity, von Kries et al…”

Sleep disturbance and cardiovascular risk in adolescents

“…27 Similarly, Senegalese girls aged 13-14 years had a reduction in sleep of 6.85 minutes for every 1.0 increase in BMI. 28 However, additional confounding factors may predispose people to adiposity and cardiovascular risk. For example, caffeine consumption (especially high-caffeine energy drinks), preference for fatty foods and reduced physical activity may simply reflect the current "usual" lifestyle of adolescents, which includes short and disturbed sleep.…”