Demetre Labadarios

Food security in South Africa: a review of national surveys

OBJECTIVE To assess the status of food security--i.e., access to food, food availability and food utilization--in South Africa. METHODS A systematic search of national surveys that used the Community Childhood Hunger Identification Project (CCHIP) index to measure food security in South Africa over a period of 10 years (1999-2008) was conducted. Anthropometric data for children aged 1-9 years were used to assess food utilization, and household food inventory data were used to assess food availability. FINDINGS Only three national surveys had used the CCHIP index, namely, the 1999 and 2005 National Food Consumption Surveys (NFCS) and the 2008 South African Social Attitudes Survey. These surveys showed a relatively large decrease in food insecurity between 1999 and 2008. However, the consistent emerging trend indicated that in poorer households women were either feeding their children a poor diet or skipping meals so their children could eat. In terms of food access and availability, the 1999 NFCS showed that households that enjoyed food security consumed an average of 16 different food items over 24 hours, whereas poorer households spent less money on food and consumed fewer than 8 different food items. Moreover, children had low mean scores for dietary diversity (3.58; standard deviation, SD: ± 1.37) and dietary variety (5.52; SD: ± 2.54) scores. In terms of food utilization, the NFCS showed that stunting in children decreased from 21.6% in 1999 to 18% in 2005. CONCLUSION The South African government must implement measures to improve the undesirably high level of food insecurity in poorer households.

How diverse is the diet of adult South Africans

BackgroundThe objective of the current study was to measure dietary diversity in South Africans aged 16 years and older from all population groups as a proxy of food security.MethodsA cross-sectional study representative of adults from all specified ages, provinces, geographic localities, and socio-economic strata in South Africa was used (n = 3287). Trained interviewers visited participants at their homes during the survey. Dietary data was collected by means of a face validated 24 hour recall which was not quantified. A dietary diversity score (DDS) was calculated by counting each of 9 food groups. A DDS <4 was regarded as reflecting poor dietary diversity and poor food security.ResultsThe provinces with the highest prevalence of poor dietary diversity (DDS <4) were Limpopo (61.8%) and the Eastern Cape (59.6%). By contrast, only 15.7% of participants in Western Cape had a low score. Participants in tribal areas (63.9%) and informal urban areas (55.7%) were by far the worst affected. There were significant differences in DDS by Living Standards Mean (LSM) analysis (p < 0.05) with the lowest LSM group having the lowest mean DDS (2.93).The most commonly consumed food groups were cereals/roots; meat/fish; dairy and vegetables other than vitamin A rich. Eggs, legumes, and vitamin A rich fruit and vegetables were the least consumed.ConclusionOverall the majority of South Africans consumed a diet low in dietary variety. The tribal areas and informal urban areas were worst affected and eggs, legumes and vitamin A rich fruit and vegetables, were the least consumed.

Relationship between serum protein and mortality in adults on long-term hemodialysis: Exhaustive review and meta-analysis

The aim of this exhaustive review and meta-analysis was to explore the relation among serum protein, inflammatory markers, and all-cause and cardiovascular mortalities in adult patients on maintenance hemodialysis. We searched the Medline, Science Citation Index, Academic Search Premier, Cochrane Library, and Embase electronic data bases. Data extraction and quality assessment were done independently by two reviewers and results were pooled using the random effects model. Cochrans Q was used to identify heterogeneity and a funnel plot was used for assessment of publication bias. A meta-analysis was performed on 38 studies (265 330 patients) reporting on serum proteins, inflammatory markers, and mortality. A significant inverse relation was found between serum albumin and all-cause (hazard ratio [HR] 0.7038, 95% confidence interval [CI] 0.6367-0.7781) and cardiovascular (HR 0.8726, 95% CI 0.7909-0.9628) mortalities, with a significantly stronger relation with all-cause mortality (P=0.0014). Pooled results for C-reactive protein showed a weak but significant direct relation with all-cause mortality (HR 1.0322, 95% CI 1.0151-1.0496), but there was not a significant relation between C-reactive protein and cardiovascular mortality (HR 1.0172, 95% CI 0.9726-1.0639). A high degree of heterogeneity was identified among studies especially in the case of all-cause mortality. An asymmetrical funnel plot for serum albumin is suggestive of publication bias. From the meta-analysis it is concluded that serum albumin showed a significant inverse relation with all-cause and cardiovascular mortalities but the relation between prealbumin and all-cause mortality was not significant. C-reactive protein showed a significant direct relation with all-cause mortality but not with cardiovascular mortality. The potential adverse effects of malnutrition and infections in relation to mortality highlight the need for continued treatment of infections and correction of malnutrition in patients on dialysis.

Micronutrient supplementation for critically ill adults: A systematic review and meta-analysis

OBJECTIVE This systematic review assessed the effects of micronutrient supplementation on adults recovering from critical illness. Primary outcomes included clinical endpoints (mortality, infectious complications, length of intensive care unit and of hospital stay). Secondary outcomes included descriptions of practice issues, micronutrient status, morbidity, course of the acute-phase response, and oxidative stress. METHODS Electronic bibliographic databases, bibliographies of retrieved articles, and personal files were searched and reviewed. Randomized controlled trials (RCTs) of micronutrient supplementation in adult critically ill patients administered enterally and/or parenterally in addition to their routine care were included. Two authors independently extracted data and assessed trial quality. The random-effects model was used to estimate overall relative risk (RR)/mean difference and effect size. P<0.05 was considered statistically significant. RESULTS Fifteen (n=1714) and 18 (n=1849) RCTs were included for the primary and secondary objectives, respectively. Fourteen trials (n=1468) showed a statistically significant decrease in overall mortality (RR 0.78, 95% confidence interval 0.67-0.90, I2=0%, P=0.0009). Six RCTs (n=1194) indicated a statistically significant decrease in 28-d mortality (RR 0.75, 95% confidence interval 0.63-0.88, I2=0%, P=0.0006). Micronutrient supplementation was not associated with a decrease in infectious complications, length of intensive care unit, or length of hospital stay. In subgroup analyses, a sensitivity analysis of combined micronutrients indicated a significant decrease in mortality (RR 0.69, 95% confidence interval 0.54-0.90, I2=2%, P=0.006). The secondary outcomes confirmed that timing, duration, and dosing appear to be key factors to ensure optimal clinical benefit. CONCLUSION This review does suggest a potential benefit of micronutrient supplementation in critically ill adults by possibly being associated with a decrease in mortality.

Estimating the burden of disease attributable to iron deficiency anaemia in South Africa in 2000

OBJECTIVES To estimate the extent of iron deficiency anaemia (IDA) among children aged 0 - 4 years and pregnant women aged 15 - 49 years, and the burden of disease attributed to IDA in South Africa in 2000. DESIGN The comparative risk assessment (CRA) methodology of the World Health Organization (WHO) was followed using local prevalence and burden estimates. IDA prevalence came from re-analysis of the South African Vitamin A Consultative Group study in the case of the children, and from a pooled estimate from several studies in the case of the pregnant women (haemoglobin level < 11 g/dl and ferritin level < 12 microg/l). Monte Carlo simulation-modelling was used for the uncertainty analysis. SETTING South Africa. SUBJECTS Children under 5 years and pregnant women 15 - 49 years. OUTCOME MEASURES Direct sequelae of IDA, maternal and perinatal deaths and disability-adjusted life years (DALYs) from mild mental disability related to IDA. Results. It is estimated that 5.1% of children and 9 - 12% of pregnant women had IDA and that about 7.3% of perinatal deaths and 4.9% of maternal deaths were attributed to IDA in 2000. Overall, about 174,976 (95% uncertainty interval 150,344 - 203,961) healthy years of life lost (YLLs), or between 0.9% and 1.3% of all DALYs in South Africa in 2000, were attributable to IDA. CONCLUSIONS This first study in South Africa to quantify the burden from IDA suggests that it is a less serious public health problem in South Africa than in many other developing countries. Nevertheless, this burden is preventable, and the study highlights the need to disseminate the food-based dietary guidelines formulated by the National Department of Health to people who need them and to monitor the impact of the food fortification programme.

Relationship Between Body Mass Index and Mortality in Adults on Maintenance Hemodialysis: A Systematic Review

OBJECTIVE The primary objective of this systematic review was to determine the relationship between body mass index (BMI) and all-cause and cardiovascular mortality. DESIGN Systematic review of primarily observational studies. PATIENTS Adult patients from all gender, race, or ethnic groups on maintenance hemodialysis. METHODS Medline, Science Citation Index, Academic Search Premier, Cochrane Library, and Embase electronic databases covering the period 1966 to December 2008 were searched with the help of a qualified librarian. Reference lists of included papers and collections also were searched. Each study was reviewed by 2 independent reviewers who also performed the data extraction from full papers. Differences between reviewers were resolved by consensus or by a third reviewer in the case of disagreements. The quality of studies selected for inclusion in the systematic review was also assessed by 2 independent reviewers. MAIN OUTCOMES BMI and mortality. RESULTS Eighteen studies (60%) reported a significant inverse relationship between all-cause mortality and BMI. This inverse relationship was more prevalent in older patients, larger retrospective studies, and studies that did not adjust for inflammation. On the other hand, 57% of the 7 studies reporting on cardiovascular mortality found no significant relationship with BMI. CONCLUSIONS This systematic review shows evidence of an inverse relationship between BMI and all-cause mortality in adult patients on maintenance HD, especially in older patients, but the relationship with cardiovascular mortality is less clear.

New insights into HIV epidemic in South Africa: key findings from the National HIV Prevalence, Incidence and Behaviour Survey, 2012

This article presents key findings from the 2012 HIV prevalence, incidence and behaviour survey conducted in South Africa and explores trends in the HIV epidemic. A representative household based survey collected behavioural and biomedical data among people of all ages. Chi-squared test for association and formal trend tests (2002, 2005, 2008 and 2012) were used to test for associations and trends in the HIV epidemic across the four surveys. In 2012 a total of 38 431 respondents were interviewed from 11 079 households; 28 997 (67.5%) of 42 950 eligible individuals provided blood specimens. HIV prevalence was 12.2% [95% CI: 11.4–13.1] in 2012 with prevalence higher among females 14.4% than males 9.9%. Adults aged 25–49 years were most affected, 25.2% [95% CI: 23.2–27.3]. HIV prevalence increased from 10.6% [95%CI: 9.8–11.6] in 2008 to 12.2% [95% CI: 11.4–13.1] in 2012 (p < 0.001). Antiretroviral treatment (ART) exposure doubled from 16.6% in 2008 to 31.2% in 2012 (p < 0.001). HIV incidence in 2012 among persons 2 years and older was 1.07% [95% CI: 0.87–1.27], with the highest incidence among Black African females aged 20–34 years at 4.5%. Sexual debut before 15 years was reported by 10.7% of respondents aged 15–24 years, and was significantly higher among male youth than female (16.7% vs. 5.0% respectively, p < 0.001). Reporting of multiple sexual partners in the previous 12 months increased from 11.5% in 2002 to 18.3% in 2012 (p < 0.001). Condom use at last sex dropped from 45.1% in 2008 to 36.2% in 2012 (p < 0.001). Levels of accurate HIV knowledge about transmission and prevention were low and had decreased between 2008 and 2012 from 31.5% to 26.8%. South Africa is on the right track with scaling up ART. However, there have been worrying increases in most HIV-related risk behaviours. These findings suggest that there is a need to scale up prevention methods that integrate biomedical, behavioural, social and structural prevention interventions to reverse the tide in the fight against HIV.

Which dietary diversity indicator is best to assess micronutrient adequacy in children 1 to 9 y

OBJECTIVES The aim of this study was to determine the best dietary diversity indicator to measure dietary diversity and micronutrient adequacy in children. METHODS A national representative cross-sectional survey of children ages 1 to 9 y (N = 2,200) was undertaken in all ethnic groups in South Africa. A 24-h recall was done with the mother or caregiver of each child. A dietary diversity score (DDS), the number of food groups consumed at least once in a period of 24 h, was calculated for each child in accordance with 6-, 9-, 13-, and 21-food group (G) indicators and compared with a mean adequacy ratio (MAR). The nutrient adequacy ratio (NAR) was calculated for 11 micronutrients by comparing the distributions of estimated intakes with the Estimated Average Requirements for that micronutrient. The MAR was the average of all NARs. Correlations were done between MAR and DDS and sensitivity and specificity calculated for each group indicator. RESULTS Pearsons correlations between food group indicators and MAR indicate that r values were all highly significant (P < 0.0001). There were no consistent or large differences found between the different group indicators although G13 and G21 appeared to be marginally better. Sensitivity and specificity values in the current study lay between DDS of 3 and 5, suggesting one of these as the best indication of (low) micronutrient adequacy. CONCLUSIONS Overall results seem to indicate that any of the four G indicators can be used in dietary assessment studies on children, with G13 and G21 being marginally better. A cut-off DDS of 4 and 5, respectively, appear best.

The Potential Impact of a 20% Tax on Sugar-Sweetened Beverages on Obesity in South African Adults: A Mathematical Model

Background/Objectives The prevalence of obesity in South Africa has risen sharply, as has the consumption of sugar-sweetened beverages (SSBs). Research shows that consumption of SSBs leads to weight gain in both adults and children, and reducing SSBs will significantly impact the prevalence of obesity and its related diseases. We estimated the effect of a 20% tax on SSBs on the prevalence of and obesity among adults in South Africa. Methods A mathematical simulation model was constructed to estimate the effect of a 20% SSB tax on the prevalence of obesity. We used consumption data from the 2012 SA National Health and Nutrition Examination Survey and a previous meta-analysis of studies on own- and cross-price elasticities of SSBs to estimate the shift in daily energy consumption expected of increased prices of SSBs, and energy balance equations to estimate shifts in body mass index. The population distribution of BMI by age and sex was modelled by fitting measured data from the SA National Income Dynamics Survey 2012 to the lognormal distribution and shifting the mean values. Uncertainty was assessed with Monte Carlo simulations. Results A 20% tax is predicted to reduce energy intake by about 36kJ per day (95% CI: 9-68kJ). Obesity is projected to reduce by 3.8% (95% CI: 0.6%–7.1%) in men and 2.4% (95% CI: 0.4%–4.4%) in women. The number of obese adults would decrease by over 220 000 (95% CI: 24 197–411 759). Conclusions Taxing SSBs could impact the burden of obesity in South Africa particularly in young adults, as one component of a multi-faceted effort to prevent obesity.

Diabetes diagnosis and care in sub-Saharan Africa: pooled analysis of individual data from 12 countries

BACKGROUND Despite widespread recognition that the burden of diabetes is rapidly growing in many countries in sub-Saharan Africa, nationally representative estimates of unmet need for diabetes diagnosis and care are in short supply for the region. We use national population-based survey data to quantify diabetes prevalence and met and unmet need for diabetes diagnosis and care in 12 countries in sub-Saharan Africa. We further estimate demographic and economic gradients of met need for diabetes diagnosis and care. METHODS We did a pooled analysis of individual-level data from nationally representative population-based surveys that met the following inclusion criteria: the data were collected during 2005-15; the data were made available at the individual level; a biomarker for diabetes was available in the dataset; and the dataset included information on use of core health services for diabetes diagnosis and care. We first quantified the population in need of diabetes diagnosis and care by estimating the prevalence of diabetes across the surveys; we also quantified the prevalence of overweight and obesity, as a major risk factor for diabetes and an indicator of need for diabetes screening. Second, we determined the level of met need for diabetes diagnosis, preventive counselling, and treatment in both the diabetic and the overweight and obese population. Finally, we did survey fixed-effects regressions to establish the demographic and economic gradients of met need for diabetes diagnosis, counselling, and treatment. FINDINGS We pooled data from 12 nationally representative population-based surveys in sub-Saharan Africa, representing 38 311 individuals with a biomarker measurement for diabetes. Across the surveys, the median prevalence of diabetes was 5% (range 2-14) and the median prevalence of overweight or obesity was 27% (range 16-68). We estimated seven measures of met need for diabetes-related care across the 12 surveys: (1) percentage of the overweight or obese population who received a blood glucose measurement (median 22% [IQR 11-37]); and percentage of the diabetic population who reported that they (2) had ever received a blood glucose measurement (median 36% [IQR 27-63]); (3) had ever been told that they had diabetes (median 27% [IQR 22-51]); (4) had ever been counselled to lose weight (median 15% [IQR 13-23]); (5) had ever been counselled to exercise (median 15% [IQR 11-30]); (6) were using oral diabetes drugs (median 25% [IQR 18-42]); and (7) were using insulin (median 11% [IQR 6-13]). Compared with those aged 15-39 years, the adjusted odds of met need for diabetes diagnosis (measures 1-3) were 2·22 to 3·53 (40-54 years) and 3·82 to 5·01 (≥55 years) times higher. The adjusted odds of met need for diabetes diagnosis also increased consistently with educational attainment and were between 3·07 and 4·56 higher for the group with 8 years or more of education than for the group with less than 1 year of education. Finally, need for diabetes care was significantly more likely to be met (measures 4-7) in the oldest age and highest educational groups. INTERPRETATION Diabetes has already reached high levels of prevalence in several countries in sub-Saharan Africa. Large proportions of need for diabetes diagnosis and care in the region remain unmet, but the patterns of unmet need vary widely across the countries in our sample. Novel health policies and programmes are urgently needed to increase awareness of diabetes and to expand coverage of preventive counselling, diagnosis, and linkage to diabetes care. Because the probability of met need for diabetes diagnosis and care consistently increases with age and educational attainment, policy makers should pay particular attention to improved access to diabetes services for young adults and people with low educational attainment. FUNDING None.