off points for hypertension in Blacks from West African and Caribbean island nationsCorrespondence to: IS Okosun, Department of Preventive Medicine and Epidemiology, Loyola University Medical Center, Stritch School of Medicine, 2160 S. First Ave, Maywood IL 60153, USA. In this analysis we examined the ability of the above cut off points to correctly identify subjects with or without hypertension in Nigeria, Cameroon, Jamaica, St Lucia and Barbados. We also determined population and gender specific abdominal adiposity cut off points for epidemiological identification of risk of hypertension.
METHODS: Waist measurement was made at the narrowest part of the torso as seen from the front or at midpoint between the bottom of the rib cage and adidas philippines instagram 2 cm above the top of the iliac crest. Sensitivity and specificity of the established WC cut off points for hypertension were compared across sites. With receiver operating characteristics (ROC), population and gender specific cut off points associated with risk of hypertension were determined over the entire range of WC values.
RESULTS: Predictive abilities of the established WC cut off points for hypertension were poor compared to the specific cut off points estimated for each population. Different values of WC were associated with increased risk of hypertension in these populations. In men, WC cut off points of 76, 81, 80, 83 and 87 cm provided the highest sensitivity for identifying hypertensives in Nigeria, Cameroon, Jamaica, St Lucia and Barbados, respectively. The analogous cut off points in women were 72, 82, 85, 86 and 88 cm.
CONCLUSIONS: The waist cut off points from this study represent values for epidemiological identification of risk of hypertension. weight reduction) and potential burden on health services if a low cut off point is employed. There is a need to develop abdominal adiposity cut off points associated with increased risks for cardiovascular diseases in different societies, especially for those populations where the distribution of obesity and associated risk factors tends to be very different from those of the technologically advanced nations.
It is increasingly being recognized that aberrant fat localization, such as abdominal adiposity, and not total body fat mass, is the most crucial determinant of cardiovascular diseases (CVDs).1,2,3,4 First described as gynoid and android morphotypes5 some 40 y ago, abdominal obesity is associated with increased risk of hypertension,6,7,8,9,10 type 2 diabetes mellitus,11,12 and stroke.13,14 Abdominal adiposity has also been shown to be associated with increased risk of overall mortality in some populations.15,16
While the 'gold standard' for assessing abdominal adiposity is the use of imaging techniques, these methods are impractical in large epidemiological studies because they are arduous and expensive. Hence, waist circumference (WC) is considered as the best anthropometric alternative for assessing abdominal adiposity.2,3,4 Waist circumference is an aggregate measurement of the actual amount of total and adidas originals abdominal fat accumulation and is a crucial correlate of abnormal syndromes found among obese and overweight patients.17,18 Indeed, many are now advocating WC as a valid alternative to body mass index (BMI) for health promotion and the basis for alert values for those at risk of CVDs.19,20,21
In epidemiological research, waist ratio (WHR) used to be the traditional anthropometric indicator for abdominal adiposity. However, because of the inherent weakness of WHR as a ratio,22,23 WC is becoming the most commonly used anthropometric surrogate of abdominal adiposity.24 In contrast to WHR, WC has the advantage of being simpler to interpret and is better correlated with levels of visceral adipose tissue accumulation.25,26,27,28,29 Visceral adiposity is highly correlated with many metabolic abnormalities that are generally regarded as part of insulin resistance syndrome (IRS).29 Components of these multiple metabolic aberrations include hypertension, glucose intolerance, hyperinsulinemia, hypercholesterolemia, hypertriglyceridemia, and high levels of low density lipoprotein cholesterol.30
There is no consensus on the WC cut off points for abdominal adiposity. The most commonly cited cut off points for abdominal adiposity are: (1) WC 94 cm for men and 80 cm for women for action level I; and adidas philippines sale 2015 (2) WC 102 cm for men and 88 cm for women for action level II.10,21 These cut off points were developed for health promotion purposes to give optimal enlightenment of individuals in need of weight management because of overweight or because of central fat distribution. Proposed originally by Lean et al,21 and subsequently by Han et al,10 at level I lifestyle modifications were recommended, while level II required the use of professional help. The NHLBI panel made the recommendations based on review of published scientific literature in MEDL1NE from 1980 to 1997 of topics identified as germane to the obesity evidence model.
Although it has been suggested that the relationship between abdominal adiposity and CVDs may differ among populations and ethnic groups,32,33 only very few studies have specifically investigated abdominal adiposity cut off points associated with different diseases in non White populations.34,35 In this study we take advantage of data collected from the International Collaborative Study of Hypertension in Blacks (ICSHIB) to (1) examine the ability of the recommended abdominal obesity cut off points to correctly identify subjects with hypertension, and (2) determine gender specific values of abdominal adiposity predictive of hypertension risk in these African origin nations.
Methods and proceduresDetailed accounts of the sampling procedures for ICSHIB have been published elsewhere.36,37,38 Briefly, ICSHIB was a multi site study using random samples of residential communities in Africa, the Caribbean and adidas stan smith the US. In this analysis, only data from West Africa and the Caribbean nations were utilized. In Nigeria, the sampling method was designed to cover rural (Idere) and urban (Ibadan) communities located in Oyo State in the southwest of Nigeria. In Cameroon, civil servants in the capital city of Yaounde and rural environs were sampled. The Caribbean samples were drawn from peri urban areas of Spanish Town, Jamaica, Bridgetown, Barbados, and Vieux Forte, St Lucia. Anthropometric measurements were obtained from participants without shoes and in light attire. Weight was measured using electronic digital scales and recorded in pounds to the nearest 0.5 lb. Height was measured in meters to the nearest 0.1 cm against a vertical wall with a rigid headboard using an inelastic tape measure. Two measurements of waist and hip circumference were made with a flexible tape for each subject to the nearest 0.1 cm. When there was a discrepancy of more than 0.5 cm between two readings, a third measurement was taken and all three measurements were recorded. Waist measurement was made at the natural waist (narrowest part of the torso as seen from the front) or at midpoint between the bottom of the rib cage and 2 cm above the top of the iliac crest. Hip measurement was made at the point of maximum extension of the buttocks. The average of the last two measurements of waist and hip were employed for this investigation.
Three blood pressure measurements were obtained from each subject using a standard mercury sphygmomanometer with 60 s intervals between cuff inflation. The average of the last two readings was utilized for this analysis. WHR was calculated as waist divided by hip circumference.
