Quality of cause of death certification at an academic hospital in Cape Town, South Africa

Objectives. To investigate the quality of cause of deathcertification and assess the level of under-reporting of HIV/AIDS as a cause of death at an academic hospital.Design. Cross-sectional descriptive retrospective review ofdeath notification forms (DNFs) of deaths due to naturalcauses in an academic hospital in Cape Town during 2004.Errors in cause of death certification and ability to code causesof death according to the 10th revision of the InternationalStatistical Classification of Diseases and Related Health Problems(ICD-10) were assessed. The association between seriouserrors and age, gender, cause of death and hospital ward wasanalysed. A sample of DNFs (N=243) was assessed for level ofunder-reporting of HIV/AIDS.Results. A total of 983 death certificates were evaluated.Almost every DNF had a minor error; serious errors werefound in 32.2% (95% confidence interval (CI) 29.3 - 35.1%).Errors increased with patient age, and cause of death wasthe most important factor associated with serious errors.Compared with neoplasms, which had the lowest error rate,the odds ratios for errors in endocrine and metabolic diseasesand genito-urinary diseases were 17.2 (95% CI 8.7 - 34.0) and17.3 (95% CI 7.8 - 38.2), respectively. Based on the sub-sample,the minimum prevalence of HIV among the deceased patientswas 15.7% (95% CI 11.1 - 20.3%) and the under-reporting ofdeaths due to AIDS was 53.1% (95% CI 35.8 - 70.4%).Conclusion. Errors were sufficiently serious to affectidentification of underlying cause of death in almost a thirdof the DNFs, confirming the need to improve the quality ofmedical certification

Emerging trends in non-communicable disease mortality in South Africa, 1997 - 2010

Objectives. National trends in age-standardised death rates (ASDRs) for non communicable diseases (NCDs) in South Africa (SA) were identified between 1997 and 2010.Methods. As part of the second National Burden of Disease Study, vital registration data were used after validity checks, proportional redistribution of missing age, sex and population group, demographic adjustments for registration incompleteness, and identification of misclassified AIDS deaths. Garbage codes were redistributed proportionally to specified codes by age, sex and population group. ASDRs were calculated using mid-year population estimates and the World Health Organization world standard.Results. Of 594 071 deaths in 2010, 38.9% were due to NCDs (42.6% females). ASDRs were 287/100 000 for cardiovascular diseases (CVDs), 114/100 000 for cancers (malignant neoplasms), 58/100 000 for chronic respiratory conditions and 52/100 000 for diabetes mellitus. An overall annual decrease of 0.4% was observed resulting from declines in stroke, ischaemic heart disease, oesophageal and lung cancer, asthma and chronic respiratory disease, while increases were observed for diabetes mellitus, renal disease, endocrine and nutritional disorders, and breast and prostate cancers. Stroke was the leading NCD cause of death, accounting for 17.5% of total NCD deaths. Compared with those for whites, NCD mortality rates for other population groups were higher at 1.3 for black Africans, 1.4 for Indians and 1.4 for coloureds, but varied by condition.Conclusions. NCDs contribute to premature mortality in SA, threatening socioeconomic development. While NCD mortality rates have decreased slightly, it is necessary to strengthen prevention and healthcare provision and monitor emerging trends in cause-specific mortality to inform these strategies if the target of 2% annual decline is to be achieved

Estimating the changing disease burden attributable to raised low-density lipoprotein cholesterol in South Africa for 2000, 2006 and 2012

Background. Low-density lipoprotein cholesterol (LDL-C) is the most important contributor to atherosclerosis, a causal factor for ischaemic heart disease (IHD) and ischaemic stroke. Although raised LDL-C is a key contributor to cardiovascular disease (CVD), the exact attributable disease risk in South Africa (SA) is unknown. The the first SA comparative risk assessment (SACRA1) study assessed the attributable burden of raised total cholesterol, and not specifically LDL-C. Objectives. To estimate the national mean serum LDL-C by age, year and sex and to quantify the burden of disease attributable to LDL-C in SA for 2000, 2006 and 2012. Methods. The comparative risk assessment (CRA) method was used. Estimates of the national mean of LDL-C, representing the 3 different years, were derived from 14 small observational studies using a meta-regression model. A theoretical minimum risk exposure level (TMREL) of 0.7 - 1.3 mmol/L was used. LDL-C estimates together with the relative risks from the Global Burden of Disease Study 2017 were used to calculate a potential impact fraction (PIF). This was applied to IHD and ischaemic stroke estimates sourced from the Second National Burden of Disease Study. Attributable deaths, years of life lost, years lived with disability and disability-adjusted life years (DALYs) were calculated. Uncertainty analysis was performed using Monte Carlo simulation. Results. LDL-C declined from 2.74 mmol/L in 2000 to 2.58 mmol/L in 2012 for males, while in females it declined from 3.05 mmol/L in 2000 to 2.91 mmol/L in 2012. The PIFs for LDL-C showed a slight decline over time, owing to the slight decrease in LDL-C levels. Attributable DALYs increased between 2000 (n=286 712) and 2006 (n=315 125), but decreased thereafter in 2012 (n=270 829). Attributable age-standardised death rates declined between 2000 and 2012 in both sexes: in males from 98 per 100 000 members of the population in 2000 to 78 per 100 000 in 2012, and in females from 81 per 100 000 in 2000 to 58 per 100 000 in 2012. Conclusions. Mean LDL-C levels were close to 3 mmol/L, which is the recommended level at which cholesterol-lowering treatment should be initiated for people at low and moderate risk for cardiovascular outcomes. The decreasing trend in the age-standardised attributable burden due to LDL-C is encouraging, but it can be lowered further with the introduction of additional population-based CVD prevention strategies. This study highlights the fact that high LDL-C concentration in relation to the TMREL in SA is responsible for a large proportion of the emerging CVD, and should be targeted by health planners to reduce disease burden

Estimating the burden of disease attributable to household air pollution from cooking with solid fuels in South Africa for 2000, 2006 and 2012

Background. Household air pollution (HAP) due to the use of solid fuels for cooking is a global problem with significant impacts on human health, especially in low- and middle-income countries. HAP remains problematic in South Africa (SA). While electrification rates have improved over the past two decades, many people still use solid fuels for cooking owing to energy poverty. Objectives. To estimate the disease burden attributable to HAP for cooking in SA over three time points: 2000, 2006 and 2012. Methods. Comparative risk assessment methodology was used. The proportion of South Africans exposed to HAP was assessed and assigned the estimated concentration of particulate matter with a diameter <2.5 μg/m3 (PM2.5) associated with HAP exposure. Health outcomes and relative risks associated with HAP exposure were identified. Population-attributable fractions and the attributable burden of disease due to HAP exposure (deaths, years of life lost, years lived with disability and disability-adjusted life years (DALYs)) for SA were calculated. Attributable burden was estimated for 2000, 2006 and 2012. For the year 2012, we estimated the attributable burden at provincial level. Results. An estimated 17.6% of the SA population was exposed to HAP in 2012. In 2012, HAP exposure was estimated to have caused 8 862 deaths (95% uncertainty interval (UI) 8 413 - 9 251) and 1.7% (95% UI 1.6% - 1.8%) of all deaths in SA, respectively. Loss of healthy life years comprised 208 816 DALYs (95% UI 195 648 - 221 007) and 1.0% of all DALYs (95% UI 0.95% - 1.0%) in 2012, respectively. Lower respiratory infections and cardiovascular disease contributed to the largest proportion of deaths and DALYs. HAP exposure due to cooking varied across provinces, and was highest in Limpopo (50.0%), Mpumalanga (27.4%) and KwaZulu-Natal (26.4%) provinces in 2012. Age standardised burden measures showed that these three provinces had the highest rates of death and DALY burden attributable to HAP. Conclusion. The burden of disease from HAP due to cooking in SA is of significant concern. Effective interventions supported by legislation and policy, together with awareness campaigns, are needed to ensure access to clean household fuels and improved cook stoves. Continued and enhanced efforts in this regard are required to ensure the burden of disease from HAP is curbed in SA

Estimating the changing disease burden attributable to iron deficiency in South Africa, 2000, 2006 and 2012

Background. Worldwide, iron deficiency, and consequent iron-deficiency anaemia, remains the most common nutritional disorder. Iron-deficiency anaemia mostly affects young children and women of reproductive age, especially in Asia and Africa. Iron deficiency may contribute to disability directly or indirectly as a risk factor for other causes of death, and may rarely contribute to death. Objectives. To estimate the changing burden of disease attributable to iron deficiency in males and females (all ages) for the years 2000, 2006 and 2012 in South Africa (SA). Methods. The comparative risk assessment methodology developed by the World Health Organization (WHO) and the Global Burden of Diseases, Injuries, and Risk Factors Studies was used to estimate the burden attributable to iron deficiency in SA for the years 2000, 2006 and 2012. We attributed 100% of the estimated iron-deficiency anaemia burden across all age groups by sex to iron deficiency. For maternal conditions, the attributable burden to iron deficiency was calculated using the counterfactual method and applied to all women of reproductive age. The population attributable fraction calculated for these selected health outcomes was then applied to local burden estimates from the Second SA National Burden of Disease Study (SANBD2). Age-standardised rates were calculated using WHO world standard population weights and SA mid-year population estimates. Results. There was a slight decrease in the prevalence of iron-deficiency anaemia in women of reproductive age from ~11.9% in 2000 to 10.0% in 2012, although the prevalence of anaemia fluctuated over time (25.5% - 33.2%), with a peak in 2006. There has been a gradual decline in the number of deaths from maternal conditions attributable to iron deficiency in SA between 2000 (351 deaths (95% uncertainty interval (UI) 248 - 436)) and 2012 (307 deaths (95% UI 118 - 470)), with a peak in 2006 (452 deaths (95% UI 301 - 589)). Furthermore, our analysis showed a 26% decrease between 2000 and 2012 in the age-standardised burden rates from maternal conditions (truncated to 15 - 49 years) attributable to iron deficiency. Between 2000 and 2012, the age-standardised disability-adjusted life year (DALY) rate from iron-deficiency anaemia attributable to iron deficiency markedly decreased by 33% in males, and increased by 3% in females of all ages. Approximately 1.1 - 1.4% of all DALYs in SA from 2000 to 2012 were attributable to iron deficiency. Conclusion. Iron-deficiency anaemia prevalence can be markedly reduced if iron deficiency is eliminated. Hence it is essential to encourage, reappraise and strengthen the measures that have been put in place to address iron deficiency, especially in women of reproductive age and children

Estimating the changing burden of disease attributable to high blood pressure in South Africa for 2000, 2006 and 2012

Background. Ongoing quantification of trends in high blood pressure and the consequent disease impact are crucial for monitoring and decision-making. This is particularly relevant in South Africa (SA) where hypertension is well-established. Objective. To quantify the burden of disease related to high systolic blood pressure (SBP) in SA for 2000, 2006 and 2012, and describe age, sex and population group differences. Methods. Using a comparative risk assessment methodology, the disease burden attributable to raised SBP was estimated according to age, se, and population group for adults aged ≥25 years in SA in the years 2000, 2006 and 2012. We conducted a meta-regression on data from nine national surveys (N=124 350) to estimate the mean and standard deviation of SBP for the selected years (1998 - 2017). Population attributable fractions were calculated from the estimated SBP distribution and relative risk, corrected for regression dilution bias for selected health outcomes associated with a raised SBP, above a theoretical minimum of 110 - 115 mmHg. The attributable burden was calculated based on the estimated total number of deaths and disability-adjusted life years (DALYs). Results. Mean SBP (mmHg) between 2000 and 2012 showed a slight increase for adults aged ≥25 years (127.3 - 128.3 for men; 124.5 - 125.2 for women), with a more noticeable increase in the prevalence of hypertension (31% - 39% in men; 34% - 40% in women). In both men and women, age-standardised rates (ASRs) for deaths and DALYs associated with raised SBP increased between 2000 and 2006 and then decreased in 2012. In 2000 and 2012, for men, the death ASR (339/100 000 v. 334/100 000) and DALYs (5 542/100 000 v. 5 423/100 000) were similar, whereas for women the death ASR decreased (318/100 000 v. 277/100 000) as did age-standardised DALYs (5 405/100 000 v. 4 778/100 000). In 2012, high SBP caused an estimated 62 314 deaths (95% uncertainty interval 62 519 - 63 608), accounting for 12.4% of all deaths. Stroke (haemorrhagic and ischaemic), hypertensive heart disease and ischaemic heart disease accounted for >80% of the disease burden attributable to raised SBP over the period. Conclusion. From 2000 to 2012, a stable mean SBP was found despite an increase in hypertension prevalence, ascribed to an improvement in the treatment of hypertension. Nevertheless, the high mortality burden attributable to high SBP underscores the need for improved care for hypertension and cardiovascular diseases, particularly stroke, to prevent morbidity and mortality

Estimating the changing burden of disease attributable to high sodium intake in South Africa for 2000, 2006 and 2012

Background. Elevated sodium consumption is associated with increased blood pressure, a major risk factor for cardiovascular and chronic kidney disease. Objectives. To quantify the deaths and disability-adjusted life years (DALYs) attributed to high sodium intake in persons aged ≥25 years in South Africa (SA) for 2000, 2006 and 2012. Methods. Comparative risk assessment (CRA) methodology was used and population attributable fractions (PAFs) of high sodium intake, mediated through high blood pressure (BP), for cardiovascular and chronic kidney disease were estimated. This was done by taking the difference between the PAF for elevated systolic BP (SBP) based on the estimated SBP level in the population and the PAF based on the estimated SBP that would result if sodium intake levels were reduced to the theoretical minimum risk exposure level (1 g/day) according to population group and hypertension categories. A meta-regression based on data from nine national surveys conducted between 1998 and 2017 was used to estimate the prevalence of hypertension by age, sex and population group. Relative risks identified from international literature were used and the difference in PAFs was applied to local burden estimates from the second South African National Burden of Disease Study. Age-standardised rates were calculated using World Health Organization (WHO) standard population weights. The attributable burden was also estimated for 2012 using an alternative target of 2 g/day proposed in the National Strategic Plan for the Prevention and Control of Non-communicable Diseases (NSP). Results. High sodium intake as mediated through high SBP was estimated to cause 8 071 (95% uncertainty interval (UI) 6 542 - 15 474) deaths in 2012, a drop from 9 574 (95% UI 8 158 - 16 526) in 2006 and 8 431 (95% UI 6 972 - 14 511) in 2000. In 2012, ischaemic heart disease caused the highest number of deaths in persons (n=1 832), followed by haemorrhagic stroke (n=1 771), ischaemic stroke (n=1 484) and then hypertensive heart disease (n=1 230). Ischaemic heart disease was the highest contributor to deaths for males (27%), whereas for females it was haemorrhagic stroke (23%). In 2012, 1.5% (95% UI 1.3 - 2.9) of total deaths and 0.7% (95% UI 0.6 - 1.2) of total DALYs were attributed to high sodium intake. If the NSP target of <2 g/day sodium intake had been achieved in 2012, ~2 943 deaths and 48 870 DALYs would have been averted. Conclusion. Despite a slight decreasing trend since 2006, high sodium intake mediated through raised BP accounted for a sizeable burden of disease in 2012. Realising SA’s target to reduce sodium intake remains a priority, and progress requires systematic monitoring and evaluation

Estimating the changing burden of disease attributable to high fasting plasma glucose in South Africa for 2000, 2006 and 2012

Background. Worldwide, higher-than-optimal fasting plasma glucose (FPG) is among the leading modifiable risk factors associated with all- cause mortality and disability-adjusted life years (DALYs) due to the direct sequelae of diabetes and the increased risk for cardiovascular and chronic kidney disease. Objectives. To report deaths and DALYs of health outcomes attributable to high FPG by age and sex for South Africa (SA) for 2000, 2006 and 2012. Methods. Comparative risk assessment methodology was used to estimate the burden attributable to high FPG. A meta-regression analysis was performed using data from national and small-area studies to estimate the population distribution of FPG and diabetes prevalence. Attributable fractions were calculated for selected health outcomes and applied to local burden estimates from the second South African National Burden of Disease Study (SANBD2). Age-standardised rates were calculated using World Health Organization world standard population weights. Results. We estimated a 5% increase in mean FPG from 5.31 (95% confidence interval (CI) 5.18 - 5.43) mmol/L to 5.57 (95% CI 5.41 - 5.72) mmol/L and a 75% increase in diabetes prevalence from 7.3% (95% CI 6.7 - 8.3) to 12.8% (95% CI 11.9 - 14.0) between 2000 and 2012. The age-standardised attributable death rate increased from 153.7 (95% CI 126.9 - 192.7) per 100 000 population in 2000 to 203.5 (95% CI 172.2 - 240.8) per 100 000 population in 2012, i.e. a 32.4% increase. During the same period, age-standardised attributable DALY rates increased by 43.8%, from 3 000 (95% CI 2 564 - 3 602) per 100 000 population in 2000 to 4 312 (95% CI 3 798 - 4 916) per 100 000 population in 2012. In each year, females had similar attributable death rates to males but higher DALY rates. A notable exception was tuberculosis, with an age-standardised attributable death rate in males double that in females in 2000 (14.3 v. 7.0 per 100 000 population) and 2.2 times higher in 2012 (18.4 v. 8.5 per 100 000 population). Similarly, attributable DALY rates were higher in males, 1.7 times higher in 2000 (323 v. 186 per 100 000 population) and 1.6 times higher in 2012 (502 v. 321 per 100 000 population). Between 2000 and 2012, the age-standardised death rate for chronic kidney disease increased by 98.3% (from 11.7 to 23.1 per 100 000 population) and the DALY rate increased by 116.9% (from 266 to 578 per 100 000 population). Conclusion. High FPG is emerging as a public health crisis, with an attributable burden doubling between 2000 and 2012. The consequences are costly in terms of quality of life, ability to earn an income, and the economic and emotional burden on individuals and their families. Urgent action is needed to curb the increase and reduce the burden associated with this risk factor. National data on FPG distribution are scant, and efforts are warranted to ensure adequate monitoring of the effectiveness of the interventions

Lead exposure in adult males in urban Transvaal Province, South Africa during the apartheid era

Human exposure to lead is a substantial public health hazard worldwide and is particularly problematic in the Republic of South Africa given the country’s late cessation of leaded petrol. Lead exposure is associated with a number of serious health issues and diseases including developmental and cognitive deficiency, hypertension and heart disease. Understanding the distribution of lifetime lead burden within a given population is critical for reducing exposure rates. Femoral bone from 101 deceased adult males living in urban Transvaal Province (now Gauteng Province), South Africa between 1960 and 1998 were analyzed for lead concentration by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Of the 72 black and 29 white individuals sampled, chronic lead exposure was apparent in nearly all individuals. White males showed significantly higher median bone lead concentration (ME = 10.04 µg·g−1), than black males (ME = 3.80 µg·g−1) despite higher socioeconomic status. Bone lead concentration covaries significantly, though weakly, with individual age. There was no significant temporal trend in bone lead concentration. These results indicate that long-term low to moderate lead exposure is the historical norm among South African males. Unexpectedly, this research indicates that white males in the sample population were more highly exposed to lead