Waist circumference and insulin resistance in elderly men: an analysis of Kahrizak elderly study

Background

Diagnosis of the metabolic syndrome (MS) is crucial for health care practitioners to identify at risk people for early treatment. Visceral obesity may make unnecessary other laborious measures of insulin resistance. The aim of this study was to see whether waist circumference (WC) can predict insulin resistance as well as MS in a group of Iranian elderly.

Methods

Out of 94 nondiabetic elderly, thirty three subjects were recognized with MS. MS diagnosis was based on NCEP ATP III (National Cholesterol Education Program Adult Treatment Panel III) and IDF (International Diabetes Federation) definitions. HOMA (Homeostasis Model Assessment) index was used to measure insulin sensitivity. Insulin resistance (IR) was defined as top quartile of HOMA.

Results

In both sexes, WC and HOMA index were significantly positively correlated. The optimal waist circumference (OWC) cutoff point was 94.5 cm for men and 90.5 cm for women. The high sensitivity (0.80) and specificity (0.84) of WC in males indicates the proportion of IR which is correctly identified and recognizes all non-IR males as such. In regression model only the TG level was associated with WC. But the WC is strongly associated with HOMA-IR.

Conclusions

While OWC is very likely a good measure to exclude non-IR subjects in our study, determination of optimal WC to identify elderly IR subjects warrants further study in a larger sample of the general population.

Impact of hypertension on various markers of subclinical atherosclerosis in early type 2 diabetes

Background

Presence of Diabetes Mellitus increases the risk of subclinical atherosclerosis. In this study was aimed to determine the influence of hypertension (HTN) on surrogate markers of atherosclerosis in a population of patients with early type 2 diabetes.

Methods

125 diabetic subjects drawn from Dr. Shariati outpatient’s clinic list and 153 non- diabetic subjects who were the relatives in law of diabetic participants were recruited. Participants with type 2 diabetes were free of clinical evidence of cardiovascular disease and renal involvement. Two groups of diabetic and control were further divided into two subgroups of hypertensive (known case of HTN or blood pressure ≥140/90 mmHg) and normotensive, and anthropometric characteristics, metabolic biomarkers as well as markers of subclinical atherosclerosis including Carotid intima media thickness (CIMT), flow mediated dilation (FMD) and Ankle Brachial Index (ABI) were measured.

Results

Diabetic group with a mean age of 49.9 ± 7.5 years had significantly higher CIMT (0.64 ± 0.14 vs 0.76 ± 0.19, p = 0.001) and lower FMD (16.5 ± 8.1 vs 13.3 ± 7.1, p = 0.003) and ABI (1.2 ± 0.1 vs 1.1 ± 0.1, p = 0.01) than control with mean age of 52.9 ± 10.1 years. 34% of control and 59.2% of diabetic were hypertensive. Fasting blood sugar, insulin levels and calculated insulin resistance index of HOMA IR. of hypertensive subjects were higher than normotensive subjects in both groups of diabetic and non-diabetic. Similar pattern was presented for measured inflammatory mediators of hs-CRP and IL-6. Among subclinical atherosclerosis markers, only CIMT was significantly different between hypertensive and normotensive subjects in both groups. In adjusted linear regression analysis, a constant significant association existed between age and CIMT, ABI and FMD in non-diabetic, while in diabetic, age only correlated with CIMT and not the other two markers. In multiple regression model, HTN was recognized as a risk factor for increasing CIMT (OR = 2.93, 95% CI = 1.03-8.33, p = 0.04) but not attenuating FMD or ABI.

Conclusions

Since FMD and CIMT may measure a different stage of subclinical atherosclerosis in diabetic patients, influence of HTN on these markers might be different.

The association of carotid intima media thickness with retinol binding protein-4 and total and high molecular weight adiponectin in type 2 diabetic patients

BACKGROUND

The aim of this study was to investigate whether carotid intima media thickness (CIMT) is associated with serum level of retinol- binding protein-4 (RBP4) and total and high molecular weight (HMW) adiponectin in type 2 diabetes (T2DM) without clinical symptom of atherosclerotic disease.

METHOD

101 type 2 diabetic patients (mean age, 53.63 ± 8.42 years) and 42 body mass index (BMI) matched control (mean age 50.1 ± 8.4) were recruited. The CIMT was assessed by using B-mode ultrasonography, while serum levels of RBP4 and total and HMW adiponectin were measured by using enzyme linked immunosorbant assay (ELISA). Linear regression analysis was performed with CIMT as dependent variable and adipokines and cardio metabolic risk factors as independent variables.

RESULT

The CIMT was higher in diabetic group compared to control group (p <0.05). The mean concentration of RBP4 and total and HMW adiponectin did not differ between two groups.Age (B = 0.44 P <0.05), blood pressure (B = 0.37 P = <0.05), waist circumference (B = -0.21 P <0.05) and TG (B = 0.1 P <0.05) were identified as independent predictors for CIMT in diabetic group, while RBP4 and adiponectin were not associated with CIMT neither in diabetic group nor in control group.

CONCLUSION

In conclusion, the present study showed that serum levels of RBP4 or total and HMW adiponectin were not potential predictors of CIMT in type 2 diabetic patients who exposed to this risk factor at least for nine years.

Carotid intima media thickness, brachial flow mediated dilation and previous history of gestational diabetes mellitus

AIM

Gestational diabetes mellitus (GDM) is a common pregnancy condition with long-term complications. We examined the association between inflammatory mediators and early atherosclerosis process by measuring the flow mediated dilatation (FMD) of brachial artery and carotid intima media thickness (CIMT) in women with previous GDM (pGDM).

MATERIAL AND METHODS

Women with and without pGDM with an average of 4 years following the indexed pregnancy, participated in this study. Serum levels of IL-6, hs-CRP, adiponectin, homocystein and other biomedical parameters were measured. The existence of early atherogenesis process was evaluated by measuring CIMT and FMD.

RESULTS

HOMA-IR and insulin were significantly higher in women with pGDM. Women with pGDM had slightly higher CIMT and significantly lower percent of brachial FMD. FMD and CIMT, adjusted for age and blood pressure, showed the same pattern. FMD showed no correlation with biochemical or inflammatory markers.

CONCLUSION

Follow-up of this group of women, who are at increased risk of cardiovascular disease, with FMD should be considered.