Consumption of processed food dietary patterns in four African populations.

OBJECTIVE: To identify predominant dietary patterns in four African populations and examine their association with obesity. DESIGN: Cross-sectional study.Setting/SubjectsWe used data from the Africa/Harvard School of Public Health Partnership for Cohort Research and Training (PaCT) pilot study established to investigate the feasibility of a multi-country longitudinal study of non-communicable chronic disease in sub-Saharan Africa. We applied principal component analysis to dietary intake data collected from an FFQ developed for PaCT to ascertain dietary patterns in Tanzania, South Africa, and peri-urban and rural Uganda. The sample consisted of 444 women and 294 men. RESULTS: We identified two dietary patterns: the Mixed Diet pattern characterized by high intakes of unprocessed foods such as vegetables and fresh fish, but also cold cuts and refined grains; and the Processed Diet pattern characterized by high intakes of salad dressing, cold cuts and sweets. Women in the highest tertile of the Processed Diet pattern score were 3·00 times more likely to be overweight (95 % CI 1·66, 5·45; prevalence=74 %) and 4·24 times more likely to be obese (95 % CI 2·23, 8·05; prevalence=44 %) than women in this pattern's lowest tertile (both P<0·0001; prevalence=47 and 14 %, respectively). We found similarly strong associations in men. There was no association between the Mixed Diet pattern and overweight or obesity. CONCLUSIONS: We identified two major dietary patterns in several African populations, a Mixed Diet pattern and a Processed Diet pattern. The Processed Diet pattern was associated with obesity.

Prevalence and risk factor for injury in sub-Saharan Africa: a multicountry study.

INTRODUCTION: Injury-related morbidity is a neglected health concern in many low-income and middle-income countries. Most injury data in Africa have been collected from hospital-based studies, and few studies have occurred across multiple countries. Using data from a novel cohort, we examined the prevalence and incidence of serious injuries and associated risk factors across five sites in sub-Saharan Africa (SSA). METHODS: A common baseline and follow-up survey was administered to participants. The study population included 1316 persons at baseline and 904 persons at follow-up. Frequencies were calculated, and logistic regression models were used to assess risk factors for injury. RESULTS: A total of 233 (17.7%) persons reported a serious injury at baseline and 60 (6.6%) reported a serious injury 6 months later at follow-up. Sixty-nine per cent of participants responded to the follow-up questionnaire. At baseline and follow-up, the most common cause of serious injury at urban sites was transport related, followed by poison/overdose. In rural Uganda, sharp instruments injuries were most common, followed by transport-related injuries. Living at an urban site was associated with an increased odds for serious injury compared with those at the rural site (OR: 1.83, 95% CI 1.15 to 2.90). Participants who consumed above a moderate amount of alcohol were at a higher risk of serious injury compared with those who did not consume alcohol (OR: 1.86, 95% CI 1.02 to 3.41). High level of education was an important risk factor for injury. CONCLUSION: At baseline and follow-up, common causes of serious injury were transport related, sharp instrument and poison/overdose. Alcohol consumption, urban location and education are important risk factors for injury. It is feasible to collect longitudinal injury data using a standardised questionnaire across multiples sites in SSA. Longitudinal data collection should be leveraged to obtain robust data on risk factors for injury in SSA.

Prevalence of chronic kidney disease and association with cardiovascular risk factors among teachers in Cape Town, South Africa.

Background: There is a need to determine the feasibility of conducting studies of chronic diseases among large cohorts of African patients. One aim of the South African feasibility study was to determine the prevalence of chronic kidney disease (CKD) and its association with cardiovascular disease (CVD) risk factors among school teachers. Methods: In a cross-sectional survey of 489 teachers we captured data on demographics, CVD risk factors, anthropometry and blood pressure. Serum glucose, creatinine, cholesterol and urine protein/creatinine ratio was measured. Glomerular filtration rate was estimated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and the Modification of Diet in Renal Disease study equations. Results: The mean (± standard deviation) age of the participants was 46.3 ± 8.5 years, with 70.3% being female and 74.6% of mixed ethnicity. The crude prevalence of CKD using the CKD-EPI equation was 6.1% while the age-adjusted prevalence was 6.4% (95% confidence interval 3.2-9.7%). CKD was associated with the presence of diabetes and higher diastolic blood pressures. Conclusions: In our study population of relatively young, working individuals CKD was common, clinically silent and associated with cardiovascular risk factors. The long-term complications of CKD are serious and expensive to manage and this, therefore, constitutes an important public health problem for South Africa.

Urban-rural and geographic differences in overweight and obesity in four sub-Saharan African adult populations: a multi-country cross-sectional study.

BACKGROUND: Overweight and obesity are on the rise in developing countries including sub-Saharan Africa. We undertook a four-country survey to show the collective burden of these health conditions as they occur currently in sub-Saharan Africa and to determine the differences between urban and rural populations and other socio-economic factors. METHODS: Participants were nurses in two hospitals in Nigeria (200), school teachers in South Africa (489) and Tanzania (229), and village residents in one peri-urban (297) and one rural location in Uganda (200) who completed a standardised questionnaire. Their height and weight were measured and body mass index calculated. Factor analysis procedure (Principal component) was used to generate a wealth index. Univariate and multivariate analyses with binary logistic regression models were conducted to examine the associations between potential correlates and the prevalence of overweight and obesity with 95 % confidence intervals. RESULTS: The prevalence of overweight and obese (combined) was 46 %, 48 %, 68 %, 75 % and 85 % in rural Uganda, peri-urban Uganda, Nigeria, Tanzania and South Africa (SA), respectively. Rural Uganda, Peri- urban Uganda, Nigeria, Tanzania and SA had obesity prevalence of 10 %, 14 %, 31 %, 40 % and 54 %, respectively (p < 0.001). Overall, prevalence of overweight was 374 (31 %) and obesity, 414 (34 %). Female sex was a predictor of overweight and obesity (combined) in peri-urban Uganda [AOR = 8.01; 95 % CI: 4.02, 15.96) and obesity in rural Uganda [AOR = 11.22; 95%CI: 2.27, 55.40), peri-urban Uganda [AOR = 27.80; 95 % CI: 7.13, 108.41) and SA [AOR = 2.17; 95 % CI: 1.19, 4.00). Increasing age was a predictor of BMI > =25 kg/m2 in Nigeria [Age > =45 - AOR = 9.11; 95 % CI: 1.72, 48.16] and SA [AOR = 6.22; 95 % CI: 2.75, 14.07], while marital status was predictor of BMI > =25 kg/m2 only in peri-urban Uganda. [Married - AOR = 4.49; 95 % CI: 1.74, 11.57]. Those in Nigeria [AOR = 2.56; 95 % CI: 1.45, 4.53], SA [AOR = 4.97; 95 % CI: 3.18, 7.78], and Tanzania [AOR = 2.68; 95 % CI: 1.60, 4.49] were more likely to have BMI > =25 kg/m2 compared with the rural and peri-urban sites. CONCLUSION: The high prevalence of overweight and obesity in these sub-Saharan African countries and the differentials in prevalence and risk factors further highlights the need for urgent focused intervention to stem this trend, especially among women, professionals and urban dwellers.

Urban and rural prevalence of diabetes and pre-diabetes and risk factors associated with diabetes in Tanzania and Uganda.

BACKGROUND: The increase in prevalence of diabetes and pre-diabetes in sub-Saharan Africa underlines the importance of understanding its magnitude and causes in different population groups. We analyzed data from the Africa/Harvard Partnership for Cohort Research and Training (PaCT) studies to determine the prevalence of diabetes and pre-diabetes and risk factors associated with diabetes. METHODOLOGY: Participants were randomly selected from peri-urban (n=297) and rural (n=200) communities in Uganda, and teachers were recruited from schools (n=229) in urban Tanzania. We used a standardized questionnaire to collect socio-demographic and self-reported disease status including diabetes status. Blood glucose was also measured after participants fasted for 8 h. We used standard protocols for anthropometric and blood pressure measurement. RESULTS: The overall prevalence of diabetes was 10.1% and was highest in rural Ugandan residents (16.1%) compared to teachers in Tanzania (8.3%) and peri-urban Ugandan residents (7.6%). The prevalence of pre-diabetes was 13.8%. The prevalence of self-reported diabetes was low across all sites, where 68% of participants with diabetes were not captured by self-report. In multivariable logistic regression analysis, family history (OR 2.5, 95% CI: 1.1, 5.6) and hypertension (OR 2.3, 95% CI: 1.1, 5.2) were significantly associated with diabetes. CONCLUSIONS: The prevalence of diabetes and pre-diabetes in Uganda and Tanzania is high, differs markedly between population groups, and remains undiagnosed in an alarmingly high proportion of individuals. These findings highlight the need for large-scale, prospective studies to accurately quantify the burden and identify effective intervention and treatment strategies across diverse African populations.

The burden of hypertension in sub-Saharan Africa: a four-country cross sectional study.

BACKGROUND: Hypertension, the leading single cause of morbidity and mortality worldwide, is a growing public health problem in sub-Saharan Africa (SSA). Few studies have estimated and compared the burden of hypertension across different SSA populations. We conducted a cross-sectional analysis of blood pressure data collected through a cohort study in four SSA countries, to estimate the prevalence of pre-hypertension, the prevalence of hypertension, and to identify the factors associated with hypertension. METHODS: Participants were from five different population groups defined by occupation and degree of urbanization, including rural and peri-urban residents in Uganda, school teachers in South Africa and Tanzania, and nurses in Nigeria. We used a standardized questionnaire to collect data on demographic and behavioral characteristics, injuries, and history of diagnoses of chronic diseases and mental health. We also made physical measurements (weight, height and blood pressure), as well as biochemical measurements; which followed standardized protocols across the country sites. Modified Poison regression modelling was used to estimate prevalence ratios (PR) as measures of association between potential risk factors and hypertension. RESULTS: The overall age-standardized prevalence of hypertension among the 1216 participants was 25.9%. Prevalence was highest among nurses with an age-standardized prevalence (ASP) of 25.8%, followed by school teachers (ASP = 23.2%), peri-urban residents (ASP = 20.5%) and lowest among rural residents (ASP = 8.7%). Only 50.0% of participants with hypertension were aware of their raised blood pressure. The overall age-standardized prevalence of pre-hypertension was 21.0%. Factors found to be associated with hypertension were: population group, older age, higher body mass index, higher fasting plasma glucose level, lower level of education, and tobacco use. CONCLUSIONS: The prevalence of hypertension and pre-hypertension are high, and differ by population group defined by occupation and degree of urbanization. Only half of the populations with hypertension are aware of their hypertension, indicating a high burden of undiagnosed and un-controlled high blood pressure in these populations.

Feasibility of a large cohort study in sub-Saharan Africa assessed through a four-country study.

BACKGROUND: Large prospective epidemiologic studies are vital in determining disease etiology and forming national health policy. Yet, such studies do not exist in sub-Saharan Africa (SSA) notwithstanding the growing burden of chronic diseases. OBJECTIVE: We explored the feasibility of establishing a large-scale multicountry prospective study at five sites in four sub-Saharan countries. DESIGN: Based on country-specific considerations of feasibility, Nigeria enrolled health care professionals, South Africa and Tanzania enrolled teachers, and Uganda enrolled village residents at one rural and one periurban site each. All sites used a 6-month follow-up period but different approaches for data collection, namely standardized questionnaires filled out by participants or face-to-face interviews. RESULTS: We enrolled 1415 participants from five sites (range 200-489) with a median age of 41 years. Approximately half had access to clean-burning cooking fuel and 70% to piped drinking water, yet 92% had access to a mobile phone. The prevalence of chronic diseases was 49% among 45- to 54-year-olds and was dominated by hypertension (21.7% overall) - ranging from 4.5 to 31.2% across sites - and a serious injury in the past 12 months (12.4% overall). About 80% of participants indicated willingness to provide blood samples. At 6-month follow-up, 68% completed a questionnaire (45 to 96% across sites) with evidence that mobile phones were particularly useful. CONCLUSIONS: Our pilot study indicates that a large-scale prospective study in SSA is feasible, and the burden of chronic disease in SSA may already be substantial necessitating urgent etiologic research and primary prevention.

Investigating the association between diabetes mellitus, depression and psychological distress in a cohort of South African teachers.

BACKGROUND: Diabetes mellitus (DM) may increase the risk of depression as a result of a sense of threat of debilitating complications or because of associated lifestyle changes. Depression may increase the risk of type 2 diabetes as a result of poor health behaviours. OBJECTIVE: To determine the association between diabetes mellitus, depression and psychological distress in a cohort of South African (SA) teachers. METHODS: Teachers from 111 public schools in the Metro South District of the Cape Metropolitan area, SA, were invited to participate in this study. The Center for Epidemiologic Studies Depression Scale (CES-D) and the Kessler Psychological Distress Scale (K10) were used to assess depression and psychological distress, respectively. A professional nurse completed a physical examination and collected blood for measurement of glucose, cholesterol and serum creatinine. RESULTS: Of the 388 teachers who completed the questionnaires, 67.5% were female and the average age was 46.2 years (standard deviation 8.7). Psychological distress was identified in 28.1% of the cohort and depression in 15.5%, and 7.7% were found to fulfil criteria for DM. A diagnosis of DM was associated with an increased risk of depression (adjusted odds ratio (AOR) 3.90; 95% confidence interval (CI) 1.33-11.37) and psychological distress (AOR 3.62; 95% CI 1.31-10.00). CONCLUSION: The high prevalence of obesity and DM in this cohort of SA teachers is of concern. A diagnosis of DM was strongly associated with an increased risk of depression and psychological distress.