The waist circumference of risk in black South african men is lower than in men of European ancestry

Identifying sex-specific anthropometric measures and thresholds for dysglycemia screening in an HIV-endemic rural South African population

Valid screening and diagnostic algorithms are needed to achieve 2030 targets proposed by the WHO's Global Diabetes Compact. We explored anthropometric thresholds to optimally screen and refer individuals for diabetes testing in rural South Africa. We evaluated screening thresholds for waist circumference (WC), body mass index (BMI), and waist-hip ratio (WHR) to detect dysglycemia based on a glycated hemoglobin (HbA1C) ≥6.5% among adults in a population-based study in South Africa using weighted, non-parametric ROC regression analyses. We then assessed the diagnostic validity of traditional obesity thresholds, explored optimal thresholds for this population, and fit models stratified by sex, age, and HIV status. The prevalence of dysglycemia in the total study population (n = 17,846) was 7.7%. WC had greater discriminatory capacity than WHR to detect dysglycemia in men (p-value<0.001) and women (p<0.001). WC had greater discriminatory capacity than BMI to detect dysglycemia in women (p<0.001). However, BMI and WC performed similarly for men (p = 0.589). Whereas traditional WC thresholds for women (>81cm) performed well (sensitivity 91%, positive predictive value [PPV] 14.9%), substantially lower thresholds were needed to achieve acceptable sensitivity and PPV among men (traditional >94cm, derived >79.5cm). WC outperforms BMI as an anthropometric screening measure for dysglycemia in rural South Africa. Whereas WC guideline thresholds are appropriate for women, male-derived WC cutoffs performed better at lower thresholds. In this rural South African population, thresholds that maximize specificity and PPV for efficient resource allocation may be preferred.

Type 2 diabetes progression in an adult Ugandan population with new-onset diabetes: an observational prospective study

BACKGROUND

The rate of progression of type 2 diabetes following diagnosis varies across individuals and populations. Studies investigating the progression of type 2 diabetes in adult African populations with newly diagnosed diabetes are limited. We aimed to investigate the prevalence and predictors of short-term (one year) diabetes progression in an adult Ugandan population with new-onset type 2 diabetes (type 2 diabetes diagnosed in < 3 months) initiated on oral hypoglycaemic agents (OHA).

METHODS

Two hundred and seven adult participants with type 2 diabetes diagnosed within the previous three months were followed up for 12 months. We investigated the association of specific demographic, clinical, and metabolic characteristics, and short-term diabetes progression (defined as glycated haemoglobin or HbA1c ≥ 8% on ≥ 2 OHA and/or treatment intensification).

RESULTS

One hundred sixteen participants (56%) completed the follow-up period. Sixty-four participants (55.2%, 95% CI 45.7-64.4) showed evidence of diabetes progression during the 12-month period of follow-up. An HbA1c ≥ 8% on ≥ 2 OHA and treatment intensification were noted in 44.8% and 29.3% of the participants, respectively. On multivariate analysis, only the female gender (AOR 3.2, 95% CI 1.1-9.2, p = 0.03) was noted to be independently associated with short-term diabetes progression.

CONCLUSION

Short-term diabetes progression was relatively common in this study population and was independently associated with the female gender. Early intensified diabetes therapy in adult Ugandan female patients with new-onset type 2 diabetes should be emphasised to avert rapid short-term diabetes progression.

Msolomba V, Venter F, Carmona S, Kao K, Gordon A, Meyer-Rath G. Integration of point-of-care screening for type 2 diabetes mellitus and hypertension with COVID-19 rapid antigen screening in Johannesburg, South Africa

AIMS

We sought to evaluate the yield and linkage-to-care for diabetes and hypertension screening alongside a study assessing the use of rapid antigen tests for COVID-19 in taxi ranks in Johannesburg, South Africa.

METHODS

Participants were recruited from Germiston taxi rank. We recorded results of blood glucose (BG), blood pressure (BP), waist circumference, smoking status, height, and weight. Participants who had elevated BG (fasting ≥7.0; random ≥11.1mmol/L) and/or BP (diastolic ≥90 and systolic ≥140mmHg) were referred to their clinic and phoned to confirm linkage.

RESULTS

1169 participants were enrolled and screened for elevated BG and elevated BP. Combining participants with a previous diagnosis of diabetes (n = 23, 2.0%; 95% CI:1.3-2.9%) and those that had an elevated BG measurement (n = 60, 5.2%; 95% CI:4.1-6.6%) at study enrollment, we estimated an overall indicative prevalence of diabetes of 7.1% (95% CI:5.7-8.7%). When combining those with known hypertension at study enrollment (n = 124, 10.6%; 95% CI:8.9-12.5%) and those with elevated BP (n = 202; 17.3%; 95% CI:15.2-19.5%), we get an overall prevalence of hypertension of 27.9% (95% CI:25.4-30.1%). Only 30.0% of those with elevated BG and 16.3% of those with elevated BP linked-to-care.

CONCLUSION

By opportunistically leveraging existing COVID-19 screening in South Africa to screen for diabetes and hypertension, 22% of participants received a potential new diagnosis. We had poor linkage-to-care following screening. Future research should evaluate options for improving linkage-to-care, and evaluate the large-scale feasibility of this simple screening tool.

Association between Metabolic Syndrome Components and Cardiac Autonomic Modulation among Children and Adolescents: A Systematic Review and Meta-Analysis

Simple Summary

The clustering of metabolic syndrome (MetS) risk factors is becoming more prevalent in young people (up to the age of 19 years) leading to the development of type 2 diabetes (T2D) and cardiovascular diseases in early adulthood. The impact of MetS risk factors on cardiac autonomic modulation (CAM) or vice versa have been noted to track from childhood to pre-adolescence and adolescence. Understating associations in this age group may help improve the clinical outcomes of the MetS, even when MetS symptoms are not visible. Potential damage from each individual MetS component and the ability to predict early cardiac damage or upcoming cardiovascular events is very important. Therefore, the present systematic review and meta-analysis investigated the associations between CAM and MetS risk factors individually to verify which MetS risk components were significantly correlated with which heart rate variability (HRV) indices before or at the onset of the MetS among young people. The purpose of this review was to outline the importance of potentially screening HRV indices in young people even with only one MetS risk factor, as a pre-indicator for early cardiovascular risk stratification. Cross-sectional studies that examined the relationship of MetS risk factors with HRV indices were searched using four databases including PubMed, the Cochrane clinical trials library, Medline and the Web of Science. Correlation coefficients with 95% confidence intervals (95% CI), and random effects meta-analyses of the association between MetS risk factors with HRV indices were performed. Our results propose that lipid profiles including high density lipoprotein (HDL) and triglycerides (TGs), waist circumference (WC) and blood pressure (BP) are associated with CAM in young people up to the age of 19 years. The use of HRV indices to predict future MetS risk, and relationships with individual risk factors including HDL, BP, WC and TGs, were established. Furthermore, arterial pressure, respiration, stress and physical activity must be taken into consideration for future studies along with CAM related to young people (up to the age of 19 years), and it is recommended to explore further the associations reported here, as CAM is not the only determinant of neurovisceral regulation.

Abstract

Background: the clustering of metabolic syndrome (MetS) risk factors is becoming more prevalent in children, leading to the development of type 2 diabetes (T2D) and cardiovascular diseases in early adulthood. The impact of MetS risk factors on cardiac autonomic modulation (CAM) or vice versa has been noted to track from childhood to pre-adolescence and adolescence. Understating associations in this age group may help to improve the clinical outcomes of the MetS, even when MetS symptoms are not visible. Potential damage from each individual MetS component and the ability to predict early cardiac damage or upcoming cardiovascular events is very important. Therefore, the present systematic review and meta-analysis investigated the associations between CAM and MetS risk factors individually to verify which of the MetS risk components were significantly correlated with heart rate variability (HRV) indices before or at the onset of the MetS among young people. The purpose of this review was to outline the importance of potentially screening HRV indices in young people even with only one MetS risk factor, as a pre-indicator for early cardiovascular risk stratification. Methods: cross-sectional studies that examined the relationship of MetS risk factors with HRV indices were searched using four databases including PubMed, the Cochrane clinical trials library, Medline and the Web of Science. Correlation coefficients with 95% confidence intervals (95% CI), and random effects meta-analyses of the association between MetS risk factors with HRV indices were performed. Results: out of 14 cross-sectional studies and one case-control study, 8 studies (10 data sets) provided association data for the meta-analysis. Our results indicated significant positive correlations for systolic blood pressure (SBP) (correlation coefficient 0.13 (95%CI: 0.06; 0.19), I² = 47.26%) and diastolic blood pressure (DBP) (correlation coefficient 0.09 (95%CI: −0.01; 0.18), I² = 0%) with a Low Frequency/High Frequency ratio (LF/HF). Significant negative correlations for waist circumference (WC) (correlation coefficient −0.12 (95%CI: −0.19; −0.04), I² = 51.50%), Triglycerides (TGs) (correlation coefficient −0.09 (95%CI: −0.15; −0.02), I² = 0%) and ≥2 MetS risk factors (correlation coefficient −0.10 (95%CI: −0.16; −0.03), I² = 0%); with high frequency (HF) were revealed. Significant positive correlations for high density lipoprotein (HDL) (correlation coefficient 0.08 (95%CI: 0.05; 0.11), I² = 0%) and significant negative correlations of ≥2 MetS risk (correlation coefficient −0.04 (95%CI: −0.12; 0.03), I² = 0.0%) with low frequency (LF) were revealed. Significant negative correlations for TGs (correlation coefficient −0.09 (95%CI: −0.23; 0.05), I² = 2.01%) with a mean square root of the sum of differences between mean time between two successive intervals (rMSSD) and significant positive correlation of HDL (correlation coefficient 0.09 (95%CI: −0.01; 0.19), I² = 0.33%) with standard deviation of the time between two successive intervals (SDNN) were also revealed. An Egger’s test indicated that there was no obvious publication bias for any of the above relationships except for TGs and rMSSD. The significance level stipulated for the meta-analysis was p < 0.05. Conclusions: lipid profiles (HDL and TGs), WC and BP were associated with CAM in young people up to the age of 19 years. The use of HRV indices to predict future MetS risk, and relationships with individual risk factors including HDL, BP, WC and TGs, were established. Future studies related to young people (up to the age of 19 years) are recommended to explore the associations reported here further.

Waist-to-height ratio is a useful indicator of cardio-metabolic risk in South Africa

BACKGROUND

The use of waist-to-height ratio has been suggested as a better proxy indicator of central obesity.

OBJECTIVE

To compare the utility of waist-to-height ratio with commonly used adiposity indices of body mass index, waist circumference and waist-to-hip ratio to identify cardio-metabolic diseases in 25-74-year-old black residents of Cape Town.

METHODS

This cross-sectional study, stratified for age and gender, determined cardio-metabolic abnormalities by administered questionnaires, clinical measurements and biochemical analyses, including oral glucose tolerance tests. Correlations between adiposity indices with cardio-metabolic components were examined. Age- and gender-adjusted logistic regression analyses determined the associations of obesity by these adiposity indices with cardio-metabolic abnormalities.

RESULTS

The study comprised 392 men and 707 women. Compared with other adiposity indices, waist-to-height ratio in men correlated most closely with fasting (0.360) and 2-hour (0.388) glucose levels, total cholesterol (0.267), low-density lipoprotein cholesterol (0.351) and triglycerides (0.400). In women, waist-to-height ratio correlated the best with systolic blood pressure (0.254) and diastolic blood pressure (0.287). Of the adiposity indices, waist circumference was most strongly associated with diabetes (odds ratio 4.27, 95% confidence interval: 2.39-7.62), low high-density lipoprotein cholesterol (2.84, 1.90-4.26) and hypertriglyceridaemia (3.60, 2.03-6.40), whereas raised waist-to-height ratio was most closely related to hypertension (1.61, 1.07-2.42), hypercholesterolaemia (1.72, 1.04-2.83) and raised low-density lipoprotein cholesterol (2.46, 1.70-3.55).

CONCLUSIONS

Compared with other adiposity indices, the better correlation of waist-to-height ratio with many cardio-metabolic components, particularly in men, and the stronger association of raised waist-to-height ratio with hypertension, hypercholesterolaemia and raised low-density lipoprotein cholesterol support the utility of waist-to-height ratio in routine assessments of adiposity in this population, which may improve the identification of cardio-metabolic risk.

Comparison of prostate size and anthropometric parameters between diabetic and non-diabetic Congolese patients who underwent transurethral prostate resection in the Democratic Republic of Congo

Background

Benign prostate hyperplasia (BPH) and type 2 diabetes mellitus are prevalent in older men, and both represent a challenge to public health. Prior studies reported a correlation between BPH and (hyper)glycaemia, a component of the metabolic syndrome, which is on the increase in sub-Saharan Africa (SSA) due to rapid modernization. This study was designed to evaluate the association of prostate volume and anthropometric parameters among diabetic and non-diabetic patients who had transurethral resection of the prostate (TURP) for BPH.

Results

We analyzed data of 159 selected patients who had TURP over a three-year period (February 2014–January 2017) for histologically confirmed BPH. Mean age in the entire cohort was 68 ± 8.5 years. Out of the 159 patients, 94 (59.1%) were non-diabetics and 65 (40.9%) were diabetics. International Prostate Symptom Score (IPSS) and fasting blood glucose were significantly higher in diabetic than in non-diabetic group (28.6 ± 4.3 vs 25.6 ± 6.4, and p 0.005; 121.7 ± 45.7 vs 85.4 ± 11.7 mg/dl, and p < 0.001, respectively). BMI and waist circumference were statistically greater in non-diabetics than in diabetics (25.1 ± 3.3 kg/m2 vs 23.6 ± 3.5 kg/m2, and p 0.008; 94.6 cm ± 10.3 vs 90.6 ± 10.4 cm, and p 0.018). Diabetic patients had larger prostate volume than non-diabetic in the working age subgroup only (< 65 years of age); beyond 65 years, this difference was not consistent (62.6 ± 23.1 cc vs 50.1 ± 20.7 cc, and p 0.027; 56.2 ± 23.7 cc vs 49 ± 20.2 cc, and p 0.15, respectively). Prostate size was significantly associated with fasting blood glucose (p = 0.002) and PSA (p = 0.027). However, prostate size was not related to age, presence of diabetes, BMI, waist circumference, IPSS, quality of life score, and duration of symptoms.

Conclusion

Prostate volume is not correlated with anthropometric parameters in diabetic and non-diabetic Congolese patients who had TURP in South Kivu. Diabetics were not obese and yet had larger prostate volume than non-diabetics < 65 years of age. It is hoped that these results would form groundwork for further studies on this topic in SSA region.

Motives for physical activity in the adoption and maintenance of physical activity in middle-aged and old age outpatients with a mental disorder: A cross-sectional study from a low-income country

Within the trans-theoretical model (stages of change) and self-determination theory frameworks, we investigated motives for physical activity adoption and maintenance in middle-aged and old age people with a mental disorder from a low-income setting. Ninety Ugandan outpatients completed the Behavioral Regulation in Exercise Questionnaire-3 (BREQ-3) to assess exercise motives and the Patient-centred Assessment and Counselling for Exercise (PACE) to determine stage of change. The relationship between motives for physical activity and stage of change was investigated using MANOVA with post-hoc Scheffe tests. Higher amotivation levels were observed in the pre-action compared with action and maintenance stages, while except for external regulation, all regulation scores were significantly lower in the pre-action compared with action and maintenance stages. There were no significant differences in levels of motivational types between the action and maintenance stage. The study provides a platform for future research to investigate relationships between motivational factors and physical and mental health outcomes within physical activity interventions for middle-aged and old age people with a mental disorder.

Indicadores de obesidade: capacidade preditiva para síndrome metabólica em adultos quilombolas

Resumo O objetivo deste estudo foi avaliar a capacidade preditiva da síndrome metabólica (SM) por diferentes indicadores de obesidade (IO) em adultos quilombolas. Estudo transversal com amostra representativa de 850 adultos (18 à 92 anos de idade) quilombolas residentes na microrregião geográfica de Guanambi/Bahia. Foram construídas curvas Receiver Operating Characteristic (ROC) entre os IO (percentual de gordura - %G; índice de adiposidade corporal – IAC; índice de massa corporal – IMC) e a SM. O equilíbrio entre sensibilidade e especificidade definiu os melhores pontos de corte preditores da SM pelos IO. Os três IO apresentaram capacidade preditiva para SM (curva ROC significativamente > 0,5). Entre as mulheres, o %G apresentou área sob a curva ROC (0,69 - IC95%: 0,65:0,73) significativamente maior que os demais IO. Entre os homens as áreas do %G e do IMC foram iguais (0,81 - IC95%: 0,76:0,85) e maiores que a do IAC. Os melhores pontos de corte dos IO para identificar a presença da SM respectivamente em mulheres e homens foram: 24,97 e 25,36 kg/m2 para IMC, 34,30 e 26,14% para IAC e 37,7 e 23,8% para %G. Os IO testados são válidos para rastrear a SM em adultos quilombolas a partir da utilização dos pontos de corte específicos para a população estudada.

Waist Circumference Cutoff Point Determination for Defining Metabolic Syndrome in Type 2 Diabetes Mellitus in Ethiopia

BACKGROUND

Metabolic syndrome (MetS) is a complex disorder characterized by a cluster of interrelated cardiovascular risk factors. So far, cutoff point variability of waist circumference was documented to define MetS.

OBJECTIVE

To determine the classification power and cutoff point of waist circumference to define MetS among patients with type 2 diabetes.

METHODS

An institution-based cross sectional study was conducted from March to April 2017 at Ayder Comprehensive Specialized Hospital among patients with type 2 diabetes. Using systematic sampling technique, 520 participants were enrolled into the study. Data were collected by checklist, anthropometric measurements and biochemical analyses. Data were entered to Epi-info 3.5.1 and transferred to SPSS 20 for analysis. Participants having more than one abnormal MetS components were categorized as patients and the others were considered as control. The classification power of waist circumference to distinguish patients from controls was determined by ROC curve analysis. Waist circumference cutoff points were determined by taking the point that had a maximum youden index.

RESULTS

Among the 520 participants, 308 (59.2%) were females. The mean age of the participants was 56 ± 10.8 years for males and 55 ± 11.4 years for females. The classification power of waist circumference was 0.67 (0.58-0.75) for male and 0.63 (0.52-0.73) for females. The optimal waist circumference cutoff point to distinguish patients from controls were 95.5 cm (sensitivity 39.8%, specificity 86.3%, p< 0.001) for males, and 87.5 cm (sensitivity 73.1%, specificity 54.5%, p< 0.017) for females.

CONCLUSION

The positive predictive value of waist circumference was 93% for females and 90% for males in Northern Ethiopia using 87.5 and 95.5 cm points cut-off for females and males, respectively.

Exercise self-efficacy correlates in people with psychosis

Despite the recognition of the importance of exercise self-efficacy in exercise adoption and maintenance, previous investigations on exercise self-efficacy in people with psychosis is scarce. The present study aimed to (1) explore if exercise self-efficacy differed between stages of behavior change in Ugandan outpatients with psychosis, and (2) assess sociodemographic, clinical and motivational correlates of exercise self-efficacy. In total, 48 patients (24 women) completed the Exercise Self-Efficacy Scale (ESES), the Patient-centered Assessment and Counseling for Exercise questionnaire, the Brief Symptoms Inventory-18 (BSI-18), and questions pertaining to intrinsic motivation in the Behavioral Regulation in Exercise Questionnaire-2. Additionally, participants were asked about their exercise behavior in the past 7 days and screened for cardio-metabolic risk factors. Higher ESES-scores were observed in those in the maintenance (n = 17) versus those in the pre-action stage (n = 17) of behavior change. Higher ESES-scores were also significantly associated with lower BSI-18 somatization and higher intrinsic motivation scores. Our data indicated that health care professionals should assist patients with psychosis in interpreting physiological states during exercise. Future research should explore whether bolstering such sources of information might directly or indirectly effect exercise self-efficacy.

Motives for physical activity in the adoption and maintenance of physical activity in men with alcohol use disorders

Within the self-determination theory and the trans-theoretical model (stages of change) frameworks, we investigated motives for physical activity adoption and maintenance in men with alcohol use disorder (AUD). Fifty Ugandan patients completed the Behavioral Regulation in Exercise Questionnaire-3 (BREQ-3) to assess exercise motives, the Patient-centred Assessment and Counselling for Exercise (PACE) to determine stage of change and the Alcohol Use Disorders Identification Test. The relationship between motives for physical activity and stage of change was investigated using ANOVA with post-hoc Scheffe tests. Multivariate analyses found significantly higher levels of introjected, identified and integrated motivation in the action and maintenance stage versus the pre-action stage. There were no differences in intrinsic motivation between the stages of change. Our results suggest that in order to adopt and maintain an active lifestyle the most important source of motivation comes from the benefits that may be obtained rather than from the inherent pleasure or challenge associated with it. The study provides a platform for future research to investigate the importance of autonomous motivation within physical activity interventions for people with AUD.

Adherence to physical activity recommendations and physical and mental health risk in people with severe mental illness in Uganda

This study investigated cardio-metabolic risk factors among patients with severe mental illness who do or do not meet the recommendations of 150min per week of physical activity. A secondary aim was to assess whether those that do meet the recommendations report lower levels of mental health symptoms. 107 (60♀) Ugandan in- and outpatients (mean age=34.4 ± 9.7 years) with severe mental illness (depression=7, bipolar disorder=55, schizophrenia=45) completed the Physical Activity Vital Sign (PAVS) method and Brief Symptoms Inventory -18. Participants were also screened for abdominal obesity (waist circumference>90cm), overweight (body mass index≥25) and hypertension (systolic pressure≥140mmHg and/or diastolic pressure≥90mmHg).48.6% (n = 52) of patients met the physical activity recommendations as assessed by the PAVS method. 41.1% (n = 44) were overweight, 40.2% (n = 43) had abdominal obesity and 23.4% (n = 25) had hypertension. Those who did not meet the physical activity recommendations were significantly older, had a higher BSI-18 somatisation score, and had a higher risk of overweight [relative risk (RR) = 2.88, 95% confidence interval (CI) = 1.59-4.99], abdominal obesity (RR = 1.82, 95%CI = 1.13-2.93), and hypertension (RR = 2.16, 95%CI = 0.99-4.73). The PAVS is a feasible method of assessing physical activity among patients with severe mental illness in a low resource setting. The PAVS may have clinical utility for physical and mental health risk stratification.

Optimal waist circumference cut-off points for predicting metabolic syndrome among low-income black South African adults

OBJECTIVE

Waist circumference has been identified as one of the strongest predictive tool for metabolic syndrome. This study determines the optimal cut-off point of waist circumference for metabolic syndrome among low-income earning South African black population, in Eastern Cape, South Africa. The optimal waist circumference cut-off point was determined through receiver operating characteristics analysis using the maximum Youden index.

RESULTS

Among men, waist circumference at a cut-off value of 95.25 cm yielded the highest Youden index of 0.773 (sensitivity = 98%, specificity = 79%, area under curve 0.893). For women, waist circumference of 89.45 cm yielded the highest Youden index of 0.339 (sensitivity = 88%, specificity = 46%, area under curve 0.713). The prevalence of metabolic syndrome among men, women and both sexes using the new cut-off points were: 17.8, 20.8 and 17.7%, respectively, compared to; 15.6, 24.8 and 21.8%, using the traditional cut-off values of 94 and 80 cm for men and women, respectively. The traditional waist circumference value slightly under-estimated the prevalence of metabolic syndrome among men and over-estimated among women and the overall population. A specific waist circumference cut-off point for South African blacks is needed for correct identification of the metabolic state of the populace in order to develop appropriate interventions.

Optimal waist circumference threshold for diagnosing metabolic syndrome in African people living with HIV infection

Background

The applicability of the internationally advocated cut-off points of waist circumference (WC) derived from Caucasians to diagnose metabolic syndrome (MS) in HIV-infected Africans is unknown. This study aimed to determine the optimal WC cutoffs for MS diagnosis in HIV-infected people receiving care at public healthcare facilities in the Western Cape Province in South Africa.

Methods

Data from 748 randomly selected participants (591 women), with a median age of 38 years, were analysed. The Youden’s index and the top-left-point approaches were used to determine the optimal cutoffs of WC for predicting ≥2 non-adipose MS components.

Results

The two approaches generated the same WC cut-off point in women, 92 cm (sensitivity 64%, specificity 64%) but different cut-off points in men: 87 cm (sensitivity 48%, specificity 85%) based on the Younden’s index and 83 cm (sensitivity 59%, specificity 74%) by the top-left-point method. The advocated thresholds of 94 cm in men had low sensitivity (30%) but high specificity (92%) whereas 80 cm in women showed low specificity (32%) but high sensitivity (85%) for diagnosing MS in this sample. Most African-specific cut-off points performed well, with 90 cm providing acceptable performance in both men (sensitivity 43%, specificity 88%) and women (sensitivity 66%, specificity 59%).

Conclusions

This study underlines the sub-optimal performance of internationally recommended WC thresholds for MS diagnosis in HIV-infected Africans, and supports the need to revisit the guidelines on WC criterion in African population across the board. A single threshold of 90 cm for both genders would be a practical suggestion.

Obesity and its Relation With Diabetes and Hypertension: A Cross-Sectional Study Across 4 Geographical Regions

BACKGROUND

The implications of rising obesity for cardiovascular health in middle-income countries has generated interest, in part because associations between obesity and cardiovascular health seem to vary across ethnic groups.

OBJECTIVE

We assessed general and central obesity in Africa, East Asia, South America, and South Asia. We further investigated whether body mass index (BMI) and waist circumference differentially relate to cardiovascular health; and associations between obesity metrics and adverse cardiovascular health vary by region.

METHODS

Using baseline anthropometric data collected between 2008 and 2012 from 7 cohorts in 9 countries, we estimated the proportion of participants with general and central obesity using BMI and waist circumference classifications, respectively, by study site. We used Poisson regression to examine the associations (prevalence ratios) of continuously measured BMI and waist circumference with prevalent diabetes and hypertension by sex. Pooled estimates across studies were computed by sex and age.

RESULTS

This study analyzed data from 31,118 participants aged 20 to 79 years. General obesity was highest in South Asian cities and central obesity was highest in South America. The proportion classified with general obesity (range 11% to 50%) tended to be lower than the proportion classified as centrally obese (range 19% to 79%). Every standard deviation higher of BMI was associated with 1.65 and 1.60 times higher probability of diabetes and 1.42 and 1.28 times higher probability of hypertension, for men and women, respectively, aged 40 to 69 years. Every standard deviation higher of waist circumference was associated with 1.48 and 1.74 times higher probability of diabetes and 1.34 and 1.31 times higher probability of hypertension, for men and women, respectively, aged 40 to 69 years. Associations of obesity measures with diabetes were strongest in South Africa among men and in South America among women. Associations with hypertension were weakest in South Africa among both sexes.

CONCLUSIONS

BMI and waist circumference were both reasonable predictors of prevalent diabetes and hypertension. Across diverse ethnicities and settings, BMI and waist circumference remain salient metrics of obesity that can identify those with increased cardiovascular risk.