Impact of introducing HbA1c into the diagnostic criteria on prevalence and cardiovascular risk profiles of individuals with newly diagnosed diabetes in Japan: the Toranomon Hospital Health Management Center Study 2 (TOPICS 2).

OBJECTIVE: To evaluate the impact of HbA1c for diagnosis of diabetes and investigate whether cardiovascular risks profiles differ among individuals with diabetes diagnosed by HbA1c or fasting plasma glucose (FPG). METHODS: This cross-sectional study involved 26,884 participants (30.6% women; aged 20-91 years) without known diabetes. Subjects were categorized into 4 groups according to the presence or absence of FPG ≥7.0 mmol/L and/or HbA1c ≥6.5%, which were American Diabetes Association criteria. Oral glucose tolerance test data were not available. RESULTS: Prevalence of undiagnosed diabetes was 3.6%. Of those individuals, 47.5% fulfilled both two criteria and 26.0% fulfilled only HbA1c criterion. Individuals with diabetes according to FPG ≥7.0 mmol/L alone were characterized as having poorly controlled hypertension while those with HbA1c ≥6.5% alone were characterized as older, female, and having lower blood pressure and γ-glutamyltransferase values. Persons with newly diagnosed diabetes by HbA1c had low HDL cholesterol and high LDL or non-HDL cholesterol levels. CONCLUSIONS: Introducing HbA1c into the diagnosis allowed detection of many previously undiagnosed cases of diabetes in Japanese individuals. Those diagnosed by FPG were characterized by hypertension and those diagnosed by HbA1c had unfavorable lipid profiles, reflecting an atherosclerotic trait.

Metabolic syndrome in Japanese men and women with special reference to the anthropometric criteria for the assessment of obesity: Proposal to use the waist-to-height ratio.

BACKGROUND: Obesity is one of the criteria for defining metabolic syndrome. However, overt obesity in Asians is relatively low despite high prevalence of metabolic risks. METHODS: We investigated the effectiveness of various anthropometric indices {body mass index (BMI), waist circumference, waist-to-height ratio (W/Ht)} for the evaluation of coronary risk factors (hypertension, hyperglycemia, hypertriglyceridemia, and low HDL cholesterol) and as one of the criteria for metabolic syndrome (clustering of three or more from one obesity and four coronary risk factors) in Japanese on 6141 men and 2137 women. RESULTS: (1) The areas under the receiver operating characteristic curves for the different anthropometric indices to identify any one and two or more coronary risk factors were highest for W/Ht. (2) The sensitivities for the identification of any one and two or more coronary risk factors were greater for W/Ht > or =0.5 than BMI > or =25, > or =23, and indices of waist circumference (Adult Treatment Panel III and Japan Society for the Study of Obesity). (3) The prevalence of metabolic syndrome varied greatly by different anthropometric indices, and the percentages of obesity risk factors in metabolic syndrome were highest for W/Ht > or =0.5 in both genders (approximate 95%). CONCLUSIONS: W/Ht >/=0.5 may be the most effective anthropometric index for screening Japanese people for metabolic syndrome.

Six reasons why the waist-to-height ratio is a rapid and effective global indicator for health risks of obesity and how its use could simplify the international public health message on obesity.

We suggest that a simple, rapid screening tool-the waist-to-height ratio (WHTR)-could help to overcome debates about the use of different body mass index (BMI) boundary values for assessing health risks in different populations. There are six reasons for our proposal: WHTR is more sensitive than BMI as an early warning of health risks. WHTR is cheaper and easier to measure and calculate than BMI. A boundary value of WHTR = 0.5 indicates increased risk for men and women. A boundary value of WHTR = 0.5 indicates increased risk for people in different ethnic groups. WHTR boundary values can be converted into a consumer-friendly chart. WHTR may allow the same boundary values for children and adults. Communicating messages about health risk could be much simpler if the same anthropometric index and the same public health message can be used throughout childhood, into adult life, and throughout the world. This simple message is: Keep your waist circumference to less than half your height.