Neighbourhood socioeconomic status and overweight/obesity: a systematic review and meta-analysis of epidemiological studies.

OBJECTIVE: Low neighbourhood socioeconomic status (NSES) has been linked to a higher risk of overweight/obesity, irrespective of the individual's own socioeconomic status. No meta-analysis study has been done on the association. Thus, this study was done to synthesise the existing evidence on the association of NSES with overweight, obesity and body mass index (BMI). DESIGN: Systematic review and meta-analysis. DATA SOURCES: PubMed, Embase, Scopus, Cochrane Library, Web of Sciences and Google Scholar databases were searched for articles published until 25 September 2019. ELIGIBILITY CRITERIA: Epidemiological studies, both longitudinal and cross-sectional ones, which examined the link of NSES to overweight, obesity or BMI, were included. DATA EXTRACTION AND SYNTHESIS: Data extraction was done by two reviewers, working independently. The methodological quality of included studies was assessed using the Newcastle-Ottawa Scale for the observational studies. The summary estimates of the relationships of NSES with overweight, obesity and BMI statuses were calculated with random-effects meta-analysis models. Heterogeneity was assessed by Cochran's Q and I2 statistics. Subgroup analyses were done by age categories, continents, study designs and NSES measures. Publication bias was assessed by visual inspection of funnel plots and Egger's regression test. RESULT: A total of 21 observational studies, covering 1 244 438 individuals, were included in this meta-analysis. Low NSES, compared with high NSES, was found to be associated with a 31% higher odds of overweight (pooled OR 1.31, 95% CI 1.16 to 1.47, p<0.001), a 45% higher odds of obesity (pooled OR 1.45, 95% CI 1.21 to 1.74, p<0.001) and a 1.09 kg/m2 increase in mean BMI (pooled beta=1.09, 95% CI 0.67 to 1.50, p<0.001). CONCLUSION: NSES disparity might be contributing to the burden of overweight/obesity. Further studies are warranted, including whether addressing NSES disparity could reduce the risk of overweight/obesity. PROSPERO REGISTRATION NUMBER: CRD42017063889.

Dietary and non-dietary determinants of linear growth status of infants and young children in Ethiopia: Hierarchical regression analysis.

INTRODUCTION: Childhood growth faltering remains a major public health problem in developing countries. We aimed to identify the distal, underlying, and proximal dietary and non-dietary factors associated with length-for-age (LFA) of infants and young children in Ethiopia. METHODS: We used a nationally representative sample of 2,932 children aged 6-23 months from the Ethiopian demographic and health survey (EDHS) conducted in 2016. Hierarchical regression analysis was done to identify the factors associated with LFA. FINDINGS: Pastoral residence (adjusted ß (aß) = -0.56, 95%CI = -0.82, -0.31, P<0.001) and poorest household wealth category (aß = -0.57, 95%CI = -0.66, -0.48, P<0.001) were the basic factors negatively associated with LFA. Among underlying factors, maternal wasting (aß = -0.43, 95%CI = -0.58, -0.28, P<0.001), and unimproved toilet facility (aß = -0.48, 95%CI = -0.73, -0.23, P<0.001) were negatively associated with LFA. Proximal factors found positively associated with LFA were dietary diversity (aß = 0.09, 95%CI = 0.043, 0.136, P<0.001), meal frequency (aß = 0.04, 95%CI = 0.00, 0.08, P = 0.042), and vitamin A supplementation (aß = 0.16, 95%CI = 0.03, 0.29, P = 0.020). Male sex (aß = -0.26, 95%CI = -0.39, -0.14, P<0.001), age (aß = -0.12, 95%CI = -0.13, -0.10, P = 0.001), small birth size (aß = -0.45, 95%CI = -0.62, -0.29, P<0.001), and not currently breastfeeding (aß = -0.29, 95%CI = -0.47, -0.11, P = 0.003) were negatively associated with LFA. CONCLUSION: LFA was associated with various influences at distal, underlying, and proximal levels. A multi-pronged approach, addressing the various factors comprehensively, would represent an important consideration to promote linear growth in early childhood in Ethiopia.

Teff consumption and anemia in pregnant Ethiopian women: a case-control study.

PURPOSE: Teff, an iron-rich staple grain in Ethiopia, is consumed mainly in the form of teff injera (TI). Studies on the association of TI consumption with anemia are limited. We aimed to determine the association of frequencies of TI consumption with anemia, in Addis Ababa, Ethiopia. METHODS: We conducted a hospital-based case-control study involving 592 pregnant women: 187 anemic cases, and 405 non-anemic controls. TI consumption was assessed by a food frequency questionnaire (FFQ). Multiple logistic regression, adjusted for dietary and non-dietary covariates, was performed to determine the relation of TI consumption to anemia status. RESULTS: We found that a decrease in frequency of TI consumption was significantly associated with an increase in the likelihood of anemia (p-trend = 0.009). Compared with everyday TI consumption, the adjusted odds ratios (AORs) of anemia associated with the other frequencies of teff consumption were 1.50 [95% confidence interval (CI) 0.71, 3.23; p = 0.285] for every other day, 2.13 (95% CI 1.03, 4.41; p = 0.04) for 1-2 times a week, and 3.17 (95% CI 1.62, 6.22; p < 0.001) for once in 2 weeks. CONCLUSIONS: Teff consumption was associated with reduced odds of anemia in pregnant women. Further studies are warranted, including determining the feasibility and effectiveness of TI use for anemia prevention. REGISTRATION: The study was registered as https://clinicaltrials.gov/ct2/show/NCT03251664 .

What does my neighbourhood have to do with my weight? A protocol for systematic review and meta-analysis of the association between neighbourhood socioeconomic status and body weight.

INTRODUCTION: Individuals living in poor neighbourhoods are at a higher risk of overweight/obesity. There is no systematic review and meta-analysis study on the association of neighbourhood socioeconomic status (NSES) with overweight/obesity. We aimed to systematically review and meta-analyse the existing evidence on the association of NSES with overweight/obesity. METHODS AND ANALYSIS: Cross-sectional, case-control and cohort studies published in English from inception to 15 May 2017 will be systematically searched using the following databases: PubMed, EMBASE, Web of Sciences and Google Scholar. Selection, screening, reviewing and data extraction will be done by two reviewers, independently and in duplicate. The Newcastle-Ottawa Scale (NOS) will be used to assess the quality of evidence. Publication bias will be checked by visual inspection of funnel plots and Egger's regression test. Heterogeneity will be checked by Higgins's method (I2 statistics). Meta-analysis will be done to estimate the pooled OR. Narrative synthesis will be performed if meta-analysis is not feasible due to high heterogeneity of studies. ETHICS AND DISSEMINATION: Ethical clearance is not required as we will be using data from published articles. Findings will be communicated through a publication in a peer-reviewed journal and presentations at professional conferences. PROSPERO REGISTRATION NUMBER: CRD42017063889.