This article is more than 5 years old. Information may no longer be current.
Prevalence of obesity, hypertension, diabetes rising in sub-Saharan Africa
Click Here to Manage Email Alerts
Rates of overweight, obesity, hypertension and type 2 diabetes are rising across both urban and rural areas of Malawi, with highest disease burden of hypertension and diabetes observed in lean, young adults, according to findings from a cross-sectional, population-based study.
“For a country that has a young population with increasing life expectancy, the already high burden of these conditions (even in adults aged 50 years or less, and the non-obese) portends high rates of cardiovascular disease-related morbidity and premature mortality in the future,” Alison J. Price, DPhil, of the department of infectious disease epidemiology at the London School of Hygiene and Tropical Medicine, and colleagues wrote. “Tobacco and alcohol consumption and physical inactivity are currently less prevalent in Malawi than in most high-income countries, but their prevalence in Malawi appears to be increasing.”
Price and colleagues analyzed data from 15,013 adults living in the city of Lilongwe and 13,878 adults living in the Karonga district in Malawi, recruited between May 2013 and February 2016 (62% women). All participants completed in-person interviews and provided fasting blood samples. Study outcomes were prevalence estimates and RRs for diabetes (defined as fasting blood glucose 7 mmol/L), hypertension (defined as systolic blood pressure 140 mm Hg and diastolic BP 90 mm Hg), overweight (BMI, 25-29.9 kg/m²) and obesity (BMI 30 kg/m²), as well as multimorbidity, stratified by area (urban vs. rural), age and sex, calculated using negative binomial regression.
Researchers found that, at all ages, urban residents were more likely to have overweight or obesity when compared with rural residents, although rates were more pronounced among adults aged 30 years or younger. The prevalence of combined overweight and obesity was 40.1% in urban areas and 19.9% in rural areas, representing a national prevalence of 23.1%. Prevalence of overweight and obesity was greatest among older, urban men and rural women aged 60 to 69 years. Within the cohort, 18% of urban men and 44% of urban women had overweight or obesity, whereas 9% of rural men and 27% of rural women had the condition.
Crude prevalence of hypertension was 14.7% among urban adults and 13.6% among rural adults, rising to 22.5% and 14.5%, respectively, when standardized to the WHO population. Rates were 16% among urban men and 14% for urban women, and rates among rural men and women were 13% and 14%, respectively. The prevalence increased steeply from a young age in both sexes, according to researchers; adults aged 50 years or younger made up a greater proportion of the burden of hypertension in both urban (57%) and rural areas (33%).
“Many people with hypertension were not overweight or obese,” the researchers wrote.
The crude prevalence of diabetes was 2.4% overall (3% among urban residents and 1.7% among rural residents), rising to 5.4% and 2.1%, respectively, after age-standardization to WHO population criteria. Rates were 3% among urban men and women, and 2% among rural men and women. Researchers also found that 47% of rural residents with diabetes and 26% of urban residents with diabetes did not have overweight or obesity.
Researchers found that multimorbidity was more likely among urban men (4%) and women (7%) than among rural men (1%) and women (2%). Few residents had all three conditions, and hypertension with obesity was the most common combination of comorbidities for all groups except rural men (diabetes and hypertension).
“Our age-specific prevalence estimates show that the risk of developing overweight or obesity, hypertension or diabetes is evident even in young adults, and therefore interventions earlier in the life course will be essential; however, immediate interventions to reduce obesity in urban women of any age are imperative,” the researchers wrote. “Our data highlight the need for mechanistic studies to understand better [noncommunicable disease] phenotypes in Africa, particularly in regard to the early age of onset of hypertension and diabetes in relatively lean and young people.” – by Regina Schaffer
Disclosure: The Wellcome Trust funded this study.
Click Here to Manage Email Alerts