Prediction of the presence of insulin resistance using general health checkup data in Japanese employees with metabolic risk factors

Construction of a Personalized Insulin Resistance Risk Assessment Tool in Xinjiang Kazakhs Based on Lipid- and Obesity-Related Indices

Purpose

This study aimed to explore the relationship between obesity- and lipid-related indices and insulin resistance (IR) and construct a personalized IR risk model for Xinjiang Kazakhs based on representative indices.

Methods

This cross-sectional study was performed from 2010 to 2012. A total of 2170 Kazakhs from Xinyuan County were selected as research subjects. IR was estimated using the homeostasis model assessment of insulin resistance. Multivariable logistic regression analysis, least absolute shrinkage and selection operator penalized regression analysis, and restricted cubic spline were applied to evaluate the association between lipid- and obesity-related indices and IR. The risk model was developed based on selected representative variables and presented using a nomogram. The model performance was assessed using the area under the ROC curve (AUC), the Hosmer–Lemeshow goodness-of-fit test, and decision curve analysis (DCA).

Results

After screening out 25 of the variables, the final risk model included four independent risk factors: smoking, sex, triglyceride-glucose (TyG) index, and body mass index (BMI). A linear dose–response relationship was observed for the BMI and TyG indices against IR risk. The AUC of the risk model was 0.720 based on an independent test and 0.716 based on a 10-fold cross-validation. Calibration curves showed good consistency between actual and predicted IR risks. The DCA demonstrated that the risk model was clinically effective.

Conclusion

The TyG index and BMI had the strongest association with IR among all obesity- and lipid-related indices, and the developed model was useful for predicting IR risk among Kazakh individuals.

Impact of Masticatory Behaviors Measured With Wearable Device on Metabolic Syndrome: Cross-sectional Study

Background

It has been widely recognized that mastication behaviors are related to the health of the whole body and to lifestyle-related diseases. However, many studies were based on subjective questionnaires or were limited to small-scale research in the laboratory due to the lack of a device for measuring mastication behaviors during the daily meal objectively. Recently, a small wearable masticatory counter device, called bitescan (Sharp Co), for measuring masticatory behavior was developed. This wearable device is designed to assess objective masticatory behavior by being worn on the ear in daily life.

Objective

This study aimed to investigate the relation between mastication behaviors in the laboratory and in daily meals and to clarify the difference in mastication behaviors between those with metabolic syndrome (MetS) and those without (non-MetS) measured using a wearable device.

Methods

A total of 99 healthy volunteers (50 men and 49 women, mean age 36.4 [SD 11.7] years) participated in this study. The mastication behaviors (ie, number of chews and bites, number of chews per bite, and chewing rate) were measured using a wearable ear-hung device. Mastication behaviors while eating a rice ball (100 g) in the laboratory and during usual meals for an entire day were monitored, and the daily energy intake was calculated. Participants’ abdominal circumference, fasting glucose concentration, blood pressure, and serum lipids were also measured. Mastication behaviors in the laboratory and during meals for 1 entire day were compared. The participants were divided into 2 groups using the Japanese criteria for MetS (positive/negative for MetS or each MetS component), and mastication behaviors were compared.

Results

Mastication behaviors in the laboratory and during daily meals were significantly correlated (number of chews r=0.36; P<.001; number of bites r=0.49; P<.001; number of chews per bite r=0.33; P=.001; and chewing rate r=0.51; P<.001). Although a positive correlation was observed between the number of chews during the 1-day meals and energy intake (r=0.26, P=.009), the number of chews per calorie ingested was negatively correlated with energy intake (r=–0.32, P=.002). Of the 99 participants, 8 fit the criteria for MetS and 14 for pre-MetS. The number of chews and bites for a rice ball in the pre-MetS(+) group was significantly lower than the pre-MetS(–) group (P=.02 and P=.04, respectively). Additionally, scores for the positive abdominal circumference and hypertension subgroups were also less than the counterpart groups (P=.004 and P=.01 for chews, P=.006 and P=.02 for bites, respectively). The number of chews and bites for an entire day in the hypertension subgroup were significantly lower than in the other groups (P=.02 and P=.006). Furthermore, the positive abdominal circumference and hypertension subgroups showed lower numbers of chews per calorie ingested for 1-day meals (P=.03 and P=.02, respectively).

Conclusions

These results suggest a relationship between masticatory behaviors in the laboratory and those during daily meals and that masticatory behaviors are associated with MetS and MetS components.

Trial Registration

University Hospital Medical Information Network Clinical Trials Registry R000034453; https://tinyurl.com/mwzrhrua

Body mass index and waist circumference are better predictors of insulin resistance than total body fat percentage in middle-aged and elderly Taiwanese

The incidence of diabetes mellitus is rising worldwide, and prediabetic screening for insulin resistance (IR) has become ever more essential. This study aimed to investigate whether body mass index (BMI), waist circumference (WC), or body fat percentage (BF%) could be a better predictor of IR in a middle-aged and elderly population. In this cross-sectional, community-based study, 394 individuals (97 with IR and 297 without IR) were enrolled in the analysis. IR was measured by homeostasis model assessment (HOMA-IR), and subjects with HOMA-IR value ≧75th percentile were defined as being IR. Associations between IR and BMI, WC and BF% were evaluated by t test, chi square, Pearson correlation, logistic regression, and receiver operating characteristic (ROC) curves. A total of 394 community-dwelling, middle-aged, and elderly persons were enrolled; 138 (35%) were male, and 256 were female (65%). The mean age was 64.41 ± 8.46 years. A significant association was identified between BMI, WC, BF%, and IR, with Pearson correlation coefficients of 0.437 (P < .001), 0.412 (P < .001), and 0.361 (P < .001), respectively. Multivariate logistic regression revealed BMI (OR = 1.31; 95% CI = 1.20-1.42), WC (OR = 1.13; 95% CI = 1.08-1.17), and BF% (OR = 1.17; 95% CI = 1.11-1.23) to be independent predictors of IR. The area under curves of BMI and WC, 0.749 and 0.745 respectively, are greater than that of BF% 0.687. BMI and WC were more strongly associated with IR than was BF%. Excess body weight and body fat distribution were more important than total body fat in predicting IR.

Lipid Accumulation Product and Hypertension Related to Stroke: a 9.2-Year Prospective Study Among Mongolians in China

AIMS

We aimed to assess the relationship between lipid accumulation product (LAP) and stroke incidence and whether increased LAP would further enlarge the risk of stroke in participants with hypertension in an Inner Mongolian population of China.

METHODS

Based on the baseline survey conducted in 2002-2003, a prospective cohort study was conducted among 2547 Mongolian people from Inner Mongolia, China. LAP was calculated by waist circumference (WC) and triglyceride (TG) concentration for men and women, respectively. Cox proportional hazards models and receiver operating characteristic (ROC) curves were used to evaluate the associations between LAP, hypertension, and stroke incidence.

RESULTS

During the follow-up period, a total of 121 stroke events were observed. Participants with higher LAP were associated with higher risk of stroke [adjusted hazard ratio (HR), 1.67; 95% confidence interval (CI), 1.08-2.58] than the participants in the lower LAP group. However, no significant dose-response relationship was detected between LAP levels and risk of stroke (P-trend=0.103). The Kaplan-Meier curves showed that hypertensives with high LAP had highest cumulative stroke incidence rate (log-rank P ＜0.001). The multivariate-adjusted HRs (95% CIs) of stroke for normotensives with high LAP, hypertensives with low LAP, and hypertensives with high LAP were 1.80 (0.84-3.89), 2.94 (1.51-5.74), and 4.23 (2.15-8.34), respectively, compared with normotensives with low LAP.

CONCLUSIONS

The present study showed that high LAP was associated with an increased risk of future stroke, and hypertensives with high LAP had the highest risk of stroke among Inner Mongolians. These findings indicate that LAP and hypertension may be valuable to predict and prevent stroke incidence.

Treatment of Mitochondrial Diabetes with a Peroxisome Proliferator-activated Receptor (PPAR)-gamma Agonist

The 3243 A>G mutation in mitochondrial DNA is the most common cause of monogenic diabetes mellitus in Japan. A 45-year-old woman with mitochondrial diabetes and significant insulin resistance presented with hypoadiponectinemia despite a normal amount of visceral fat. Three months of treatment with pioglitazone (PIO) improved her blood glucose profile and response to the 75-g oral glucose tolerance test. These changes were accompanied by the amelioration of her insulin resistance and the impairment of early-phase insulin secretion. Her serum adiponectin levels increased to the normal range. In this case of mitochondrial diabetes, PIO was effective for glycemic control.

Effects of Aging on Visceral and Subcutaneous Fat Areas and on Homeostasis Model Assessment of Insulin Resistance and Insulin Secretion Capacity in a Comprehensive Health Checkup

AIM

The association between aging and insulin resistance has been unclear. We evaluated the effects of aging on visceral fat area (VFA) and subcutaneous fat area (SFA) measured by computed tomography, homeostasis model assessment of insulin resistance (HOMA-IR), and homeostasis model assessment of β-cell function (HOMA-β) among participants in a comprehensive health checkup.

METHODS

This study included 1,050 male and 700 female Japanese participants aged 35-84 years in our comprehensive health checkup program during a 2-year period. Participants who were on medication for diabetes mellitus or those who met the pre-determined exclusion criteria were excluded. The participants were divided into five groups according to age.

RESULTS

As age increased from Group 1 to Group 5, both VFA and VFA/SFA ratio significantly increased in both male and female participants, whereas log[HOMA-IR] linearly and significantly decreased (p＜0.0001 for each). Body mass index (BMI), waist circumference (WC), and SFA increased with age in female participants but decreased in male participants. Although age was not or only weakly correlated with log[glucose] and log[HbA1c] in both male and female participants, age showed significant negative correlations with log[insulin], log[HOMA-IR], and log[HOMA-β] even after adjusting for BMI and WC (p＜0.0001 for each). Serum high-molecular-weight adiponectin (HMW-ADPN) levels were measured in 114 male and 87 female participants, and log[HMW-ADPN] was negatively correlated with log[HOMA-IR] and positively correlated with age in both male and female participants.

CONCLUSIONS

In the present study, both male and female participants showed increases in VFA and VFA/SFA ratio and decreases in insulin, HOMA-IR, and HOMA-β with age.