Sedentariness and overweight in relation to mortality in Sub-Saharan Africa. A Mediation analysis based on the WHO-Global Health Observatory Data Repository

ABSTRACT

Aims: The aim of the study was to investigate the complex mediation analysis between physical inactivity and overweight in relation to mortality. Methods: The study is based on public data collected by the Global Health Observatory (GHO) of the World Health Organisation. Results: We showed that the median early mortality attributable to NCDs during the period 2016 - 2019 in both men and women all together was 23.2% (5th to 95th range = 17.2, 35.6) while that in men alone was 25.1% (16.5, 45.7) and that of women was 22.0% (17.0, 27.9). When considering regional early NCDs mortality for both men and women, a systematically high median was observed in Southern Africa (28.7% (22.2, 43.8)) and a low median in Eastern Africa (21.1% (17.15, 27.3)). The analysis of the overall relation between physical inactivity, overweight and early mortality due to NCDs revealed a statistical significance of the direct association between physical inactivity and early mortality due to NCDs. Conclusion: Our findings revealed three main epidemiological and public health concerns. First, an early mortality attributable to NCDs in a range of about 20% to 30% across the SSA regions for both sexes were observed. Second, there was a direct effect between physical inactivity and early NCDs mortality as well as for the indirect effect mediated by overweight. Finally, a percentage point decrease of physical inactivity prevalence and overweight could effectively generate a reduction of mortality due to NCDs. Future studies are needed to confirm the scientific evidence observed in this study. Such studies should be based on observation of individual subjects, adopt a longitudinal design, and collect information that evaluate the complex relation between physical inactivity and early NCDs mortality, along with the role of overweight as a possible mediator.