https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(05)17741-1.pdf

Global burden of hypertension: analysis of worldwide data

PurposeTo examine the prevalence and the level of awareness, treatment and control of hypertension in different world regions.Study selectionA literature search of the MEDLINE database, using the Medical Subject Headings prevalence, hypertension, blood pressure and cross-sectional studies, was condu

Worldwide prevalence of hypertension: a systematic review.

Sodium-to-Potassium Ratio and Blood Pressure, Hypertension, and Related Factors

Current waist circumference (WC) and waist-to-hip ratio (WHR) cutoffs have been identified from studies of predominantly European-derived populations. However, these cutoffs may not be appropriate for other ethnic groups. This paper reviews the literature regarding ethnic differences in body composition and the appropriateness of ethnic-specific WC and WHR cutoffs in various ethnic groups. Studies investigating ethnic-specific cutoffs were identified among Aboriginal, Asian, African (Sub-Saharan), African-American, Hispanic, Middle Eastern, Pacific Islander and South American populations. Abstracts that recommended WC and/or WHR cutoffs (or rejected the use of cutoffs) were included with their supporting literature. The evidence for ethnic-specific WC and/or WHR cutoffs was then rated as either convincing, probable, possible or insufficient. The majority of studies recommending ethnic-specific cutoffs was for Asian populations. Few studies recommended cutoffs in Aboriginal, African (Sub-Saharan), Pacific Islanders and South American populations. All studies were cross-sectional, and the overwhelming majority of studies used receiver operating characteristic curves. The studies used a number of methods for assessing WC and WHR, and a variety of outcome measures, making cross-study comparison difficult. There is possible evidence that Asians should have a lower WC cutoff than Europeans. The evidence is insufficient for specific cutoffs for African-American, Hispanic and Middle Eastern populations but some studies indicate current cutoffs for Europeans may be appropriate, whereas there is insufficient evidence for the other ethnic groups. Future studies are needed to address the methodological limitations of the current literature.

Appropriateness of waist circumference and waist-to-hip ratio cutoffs for different ethnic groups.

Introduction In sub-Saharan Africa (SSA), data on hypertension prevalence in terms of urban or rural and sex difference are lacking, heterogeneous or contradictory. In addition, there are no accurate estimates of hypertension burden. Objective To estimate the age-specific and sex-specific prevalence of arterial hypertension in SSA in urban and rural adult populations. Methods We searched for population studies, conducted from 1998 through 2008 in SSA. We extracted data from selected studies on available prevalences and used a logistic regression model to estimate all age/sex/habitat (urban/rural)/country-specific prevalences for SSA up to 2008 and 2025. On the basis of the United Nations Population Fund data for 2008 and predictions for 2025, we estimated the number of hypertensives in both years. Results Seventeen studies pertaining to 11 countries were analysed. The overall prevalence rate of hypertension in SSA for 2008 was estimated at 16.2% [95% confidence interval (CI) 14.1-20.3], ranging from 10.6% in Ethiopia to 26.9% in Ghana. The estimated prevalence was 13.7% in rural areas, 20.7% in urban areas, 16.8% in males, and 15.7% in women. The total number of hypertensives in SSA was estimated at 75 million (95% CI 65-93 million) in 2008 and at 125.5 million (95% CI 111.0-162.9 million) by 2025. Conclusion The estimated number of hypertensives in 2008 is nearly four times higher than the last (2005) estimate of the World Health Organization Regional Office for Africa. Prevalences were significantly higher in urban than in rural populations. Population data are lacking in many countries underlining the need for national surveys.

Current and projected prevalence of arterial hypertension in sub-Saharan Africa by sex, age and habitat: an estimate from population studies.

We have evaluated the relationship between systolic blood pressure (SBP) and age, body mass index (BMI), waist circumference, sodium to potassium ratio (Na/K), and tobacco use in an urban African population. We conducted a random, population-based, cross-sectional survey of people 25 years and older in Marondera, Zimbabwe, with over-sampling in older age groups (n = 775), using a method comparable to that used in International Collaborative Study on Hypertension in Blacks (ICSHIB). The age-adjusted prevalences of hypertension in Marondera (SBP >/=140/DBP >/=90/antihypertensive medication) were 30% for women and 21% for men. The average BMI was 26.3 kg/m2 for women and 21.4 kg/m2 for men. The prevalence of hypertension had a steep association with age and in women ranged from 15% (25-34 years) to 63% (55 years and over) and in men from 9% to 47%. No tobacco use in women and greater Na/K ratio in spot urines in men were significantly associated with an increased SBP. In both men and women the levels of hypertension and SBP were strongly positively associated with BMI, although the relationship appeared to plateau in women with a BMI greater than >/=25 kg/m2. At a given BMI, men and women had similar SBPs and prevalences of hypertension. There is a very high prevalence of hypertension among urban Zimbabweans, particularly among women. Under the assumption the studies are comparable, the prevalence of hypertension in Zimbabwean women (41%) and men (26%) after age adjustment to the ICSHIB populations, appeared higher than almost all of the ICSHIB populations, including those with higher average body mass indexes. Journal of Human Hypertension (2000) 14, 65-73.

Correlates of blood pressure in an urban Zimbabwean population and comparison to other populations of African origin.

The prevalence of microalbuminuria (MAU) in African populations has not been reported, nor has the relationship between MAU and hypertension been reported for these populations. We collected spot urine samples from 370 women, 25 years and older as a part of a population-based, cross-sectional blood pressure survey in an urban community in Zimbabwe and analysed the samples for albumin and β2-microglobulin. The age-adjusted prevalence of hypertension was 30% for women 25 years and older in this community. After excluding the samples with hematuria (11%), the prevalence of MAU (3.0 ⩽ albumin-to-creatinine ratio (ACR, mg/mmol) <25.0) in the study population was 9%. when age-adjusted to the population in the community, the prevalence was 8% among women 25 years and older. the prevalence of mau was substantially higher in hypertensive (ht) than in normotensive (nt) women (16% vs 4%, P < 0.001). a significantly higher level of log acr in ht was found in each age group except the youngest age group (age 25–34). in age-adjusted multiple regression, percent fat mass was negatively associated with log acr (β = −1.18, 95% ci (−0.23, −2.21), P = 0.02). In a similar regression analysis, higher log β8-microglobulin-to-creatinine ratio was very strongly associated with higher log ACR (β = 0.34, 95% CI (0.25, 0.43), P < 0.0001) and significantly associated with lower percent fat mass (β = −1.02, 95% ci (−0.25, −1.8), P = 0.01). These results suggest that MAU is frequently caused by hypertension, but that other diseases may contribute to its presence.

L.J. Scott

Papers

Correlates of blood pressure in an urban Zimbabwean population and comparison to other populations of African origin.

Microalbuminuria in urban Zimbabwean women

Microalbuminuria in Urban Zimbabwean Women