Effective waist circumference reduction rate necessary to avoid the development of type 2 diabetes in Japanese men with abdominal obesity

Abstract

The aim of this study was to determine the effective waist circumference (WC) reduction rate in avoiding the development of type 2 diabetes mellitus (T2DM) in <55 years and ≥55 years Japanese men with abdominal obesity. The study subjects were 795 men with WC ≥85 cm, fasting plasma glucose <126 mg/dL, 2-hr plasma glucose on 75 g of oral glucose tolerance test <200 mg/dL, and HbA1c 5.6-6.4 % (38-40 mmol/mol) at baseline who underwent general health checkups more than twice between April 2007 and May 2015. They were divided into 5 groups based on the change in WC during the observation period (WC gain group, and four groups stratified according the rate of WC loss). The subjects were also divided into the <55 years and ≥55 years (at baseline) subgroups. The cumulative incidence rate of T2DM was analyzed and compared among the groups. The cumulative incidence rates of the largest WC loss quartile (≥5.45 %) in all age, of the largest WC loss quartile (≥5.60 %) and second largest WC loss quartile (3.44-5.59 %) in the <55 years subgroup, and of the largest WC loss quartile (≥5.37 %) in the ≥55 years subgroup were significantly lower than that of the gain group (p<0.001, p=0.009, 0.012, and 0.012, respectively). WC reduction rate of at least about 3 % in the younger (<55 years) and at least about 5 % in the older (≥55 years) non-diabetic Japanese men with abdominal obesity can effectively reduce the chance of development of T2DM.

Association of Waist Circumference Gain and Incident Prediabetes Defined by Fasting Glucose: A Seven-Year Longitudinal Study in Beijing, China

“…Previous studies have assessed the relationship between abdominal obesity and diabetes incidence [ 24 , 25 , 26 , 27 , 28 , 29 , 30 , 33 , 34 ]. Nevertheless, whether the long-term dynamic increase in WC leads to prediabetes is not well described.…”

“…Similar to prior longitudinal population-based studies about obesity and diabetes, we found a strong positive association between WC gain and prediabetes. The Suita Study in an urban area of Japan demonstrated that preventing WC gain is important in preventing type 2 diabetes in the Japanese population, especially among participants with a relatively high level of WC [ 28 ]. WC gain can reflect a specific accumulation of visceral adipose tissue, which may cause insulin resistance, contributing to type 2 diabetes.…”

“…WC gain can reflect a specific accumulation of visceral adipose tissue, which may cause insulin resistance, contributing to type 2 diabetes. A previous study reported that effective WC reduction rate can reduce the risk of development of type 2 diabetes in non-diabetic Japanese men with abdominal obesity [ 28 ]. The Newcastle Group’s study indicated the remission of type 2 diabetes when abdominal fat is drastically reduced by the use of low-calorie diet.…”

“…The cut-off points for WC are inevitably arbitrary. Only one study assessed the association between the percent WC gain and incident diabetes [ 28 ]. Moreover, no study has investigated the association between percent gain in WC and the risk of prediabetes.…”

“…Hence, whether WC dynamic change plays an important role in development of diabetes or prediabetes has not been well documented. Only two studies in Japan have assessed the relationship between WC change and diabetes risk [ 27 , 28 ]. The studies showed that monitoring WC gain is effective in preventing type 2 diabetes occurrence in the Japanese population, especially for individuals with a high WC.…”