Environmental factors associated with overweight among adults in Nigeria

TLDR

Environmental determinants of obesity are understudied in Africa, limiting tailored interventions. The study investigated how neighborhood environmental factors relate to overweight among Nigerian adults. A cross‑sectional survey of 1,818 adults aged 20‑65 in high‑ and low‑SES neighborhoods of Maiduguri measured height, weight, and 16 perceived environmental items, defining overweight as BMI ≥ 25 versus normal weight (18.5‑24.9). After adjusting for sociodemographic variables, overweight was associated with distant commercial access, poor aesthetics, garbage/odors, nighttime crime and traffic hazards, with gender‑specific interactions showing density and pedestrian pathways linked to overweight in men and lack of beauty and high traffic linked to overweight in women, confirming that neighborhood environment predicts overweight in Nigerian adults and aligning with international evidence but warranting further African replication.

Abstract

Understanding environmental factors related to obesity can inform interventions for the world wide obesity epidemic, yet no study has been conducted in this context in Africa. This study examined associations between neighbourhood environment variables and overweight in Nigerian adults. A total of 1818 randomly selected residents (age: 20-65 years, 40% female, 31% overweight and 61.2% response) living in high and low socioeconomic (SES) neighbourhoods in Metropolitan Maiduguri, Nigeria, participated in a cross-sectional study. Anthropometric measurements of height and weight and an interview-assisted self-reported measure of 16 items of perceived neighborhood environments were conducted. The primary outcome was overweight (body mass index [BMI] > or = 25 kg/m2) vs. normal weight (BMI = 18.5-24.9 kg/m2). After adjustment for sociodemographic variables, overweight was associated with distant access to commercial facilities (odds ratio [OR], 1.49; 95% confidence interval [CI], 1.02- 2.18), poor neighbourhood aesthetics (OR, 1.58; 95% CI, 1.16-2.09), perceiving garbage and offensive odours in the neighbourhood (OR, 1.41; 95% CI, 1.05-1.89) and feeling unsafe from crime at night (OR, 1.47; 95% CI, 1.13- 1.91) and unsafe from traffic (OR, 1.56; 95% CI, 1.17-2.07) in the total sample. Significant interactions regarding overweight were found between gender and four environmental variables, with low residential density (OR, 1.39; 95% CI, 1.02-1.93) and poorly maintained pedestrian pathways (OR, 1.89; 95% CI, 1.13-3.17) associated with overweight in men only, and absence of beautiful things (OR, 2.23; 95% CI, 1.42-3.50) and high traffic making it unsafe to walk (OR, 2.39; 95% CI, 1.49-3.83) associated with overweight in women only. There were few significant interactions between environmental factors and neighborhood SES regarding overweight. Neighbourhood environment factors were associated with being overweight among Nigerian adults. These findings support previous reports in international literature, but should be replicated in other African studies before any firm conclusions can be drawn.