Department of Epidemiology and Medical Statistics, Faculty of Public Health, College of Medicine, University of Ibadan, Ibadan, Nigeria.
Population Studies and Demography Programme & Population and Health Research Entity, Faculty of Humanities, North-West University, Mmabatho, South Africa.
PLoS One. 2021 Mar 29;16(3):e0249289. doi: 10.1371/journal.pone.0249289. eCollection 2021.
Underweight and overweight constitute unhealthy bodyweight and their coexistence is symptomatic of the dual burden of malnutrition (DBM) of high public health concern in many sub-Saharan Africa countries. Little is known about DBM and its correlates in Malawi, a country undergoing urbanisation. The study examined net effects of urban residence on unhealthy weights amidst individual- and community-level factors among women in Malawi.
Data on 7231 women aged 15-49 years nested within 850 communities extracted from 2015-16 Malawi Demographic and Health Survey were analysed. Women's weight status measured by body mass index, operationally categorised as underweight, normal and overweight, was the outcome variable while urban-rural residence was the main explanatory variable. Multilevel multinomial logistic regression analysis was employed at 5% significant level; the relative-risk ratio (RR) and its 95% confidence interval (CI) were presented.
Urban residents had a significantly higher prevalence of overweight than rural (36.4% vs. 17.2%; p< 0.001) but a -non-significant lower prevalence of underweight (6.2% vs. 7.4%; p = 0.423). Having adjusted for both individual- and community-level covariates, compared to rural, living in urban (aRR = 1.25; CI: 1.02-1.53) accounted for about 25% higher risk of being overweight relative to normal weight. Higher education attainment, being married and belonging to Chewa, Lomwe or Mang'anja ethnic group significantly reduced the risk of being underweight but heightened the risk of being overweight. Being older and living in wealthier households respectively accounted for about 3- and 2-times higher likelihood of being overweight, while breastfeeding (aRR = 0.65; CI: 0.55-0.76) was protective against overweight. Living in communities with higher poverty and higher education levels reduced and increased the risk of being overweight, respectively. Evidence of community's variability in unhealthy weights was observed in that 11.1% and 3.0% respectively of the variance in the likelihood of being overweight and underweight occurred across communities.
The study demonstrated association between urban residence and women overweight. Other important associated factors of overweight included breastfeeding, community education- and poverty-level, while education attainment, marital status and ethnicity were associated with the dual unhealthy weight. Thus, both individual- and community-level characteristics are important considerations for policy makers in designing interventions to address DBM in Malawi.
体重过轻和超重都属于不健康的体重，而两者同时存在则是撒哈拉以南非洲国家高度关注的营养双重负担（DBM）的症状。马拉维是一个正在经历城市化的国家，人们对 DBM 及其相关问题知之甚少。本研究考察了个体和社区层面因素对马拉维女性中城市居住与不健康体重之间的净效应。
本研究分析了 2015-16 年马拉维人口与健康调查中嵌套在 850 个社区内的 7231 名 15-49 岁女性的数据。以体重指数衡量的女性体重状况为因变量，操作上分为体重过轻、正常和超重，而城乡居住状况为主要解释变量。在 5%的显著水平上采用多水平多项逻辑回归分析；呈现相对风险比（RR）及其 95%置信区间（CI）。
与农村相比，城市居民超重的比例明显更高（36.4%比 17.2%；p<0.001），但体重过轻的比例略低（6.2%比 7.4%；p=0.423）。在调整了个体和社区层面的混杂因素后，与农村相比，城市居住（aRR=1.25；CI：1.02-1.53）导致超重的风险相对正常体重增加约 25%。较高的教育程度、已婚以及属于切瓦族、隆韦族或曼甘贾族显著降低了体重过轻的风险，但增加了超重的风险。年龄较大和居住在较富裕家庭分别导致超重的可能性增加了约 3 倍和 2 倍，而母乳喂养（aRR=0.65；CI：0.55-0.76）则可预防超重。生活在贫困程度较高和教育程度较高的社区，分别会增加和降低超重的风险。研究还发现，社区在不健康体重方面存在变异性，即社区间超重和体重过轻的可能性分别存在 11.1%和 3.0%的差异。
本研究表明城市居住与女性超重之间存在关联。超重的其他重要相关因素包括母乳喂养、社区教育和贫困水平，而教育程度、婚姻状况和族裔与双重不健康体重有关。因此，个体和社区层面的特征都是马拉维决策者在制定干预措施以解决 DBM 问题时需要考虑的重要因素。
