Insulinaemia and slight overweight: the case of Vietnamese hypertensives.

OBJECTIVE: To examine the relationship between hypertension, overweight and indices of insulin resistance in Vietnamese subjects. PATIENTS: One hundred and eight hypertensive subjects (51 men and 57 women) over 40 y of age were compared with 36 control subjects over 40 y of age. METHODS: Blood glucose and plasma insulin were measured at fasting and 2 h after 75 g glucose taken orally. RESULTS: Hypertensive subjects had significantly higher body mass index (BMI), triceps skinfold, waist and hip circumferences and waist/hip ratio. Glycaemia at fasting and after glucose were similar in the two groups. Insulinaemia at fasting and after glucose were significantly higher in the hypertensive subjects. In the whole series of hypertensive subjects, plasma insulin and insulin/glucose ratio at fasting and after glucose correlated significantly with BMI, triceps skinfold and waist and hip cicumferences. After exclusion of the subjects with BMI > 22 kg/m2, compared with the controls, plasma insulin and insulin/glucose ratio were significantly higher in the whole hypertensive group and separately in hypertensive men and women. The logistic regression analyses have shown that plasma insulin and insulin/glucose ratio at fasting and after glucose were significantly associated with hypertension, independently of gender, BMI and waist circumference. CONCLUSION: This study shows that in Vietnamese people, essential hypertension is associated with a significant increase in BMI, which however remains far lower than the definition threshold of occidental obesity and with a state of insulin resistance found despite very slight or no excess weight.

[Insulin resistance and essential hypertension in Vietnamese subjects]. / Insulinorésistance et hypertension artérielle essentielle chez les Vietnamiens.

Several epidemiological and experimental studies suggest that essential arterial hypertension is associated with hyperinsulinism and insulin resistance in obese subjects and also in subjects with normal body weight. Undernutrition remains frequent in adult Vietnamese people and mean body mass index is around 18.5 kg/m2 in Vietnam. The aim of this study was to look for insulin resistance in hypertensive Vietnamese subjects, despite a markedly lower BMI in Vietnam than in occidental countries. One hundred and eight hypertensive patients (51 men and 57 women) over 40 years (mean = 65.4 years) were compared with 36 healthy subjects (23 men and 13 women) over 40 years (mean = 63.8 years). Hypertensive patients had significantly higher BMI (20.5 +/- 0.3 (SEM) kg/m2 vs 18.4 +/- 0.4 kg/m2; p < 0.01), thicker triceps skinfold (1.26 +/- 0.07 cm vs 0.71 +/- 0.07 cm; p < 0.001) and not significantly different waist/hip ratio (0.88 +/- 0.01 vs 0.85 +/- 0.01). Blood glucose at fasting and 2 hours after 75 g glucose taken orally were similar in hypertensive and normotensive subjects. Plasma insulin at fasting and 2 hours after glucose were significantly higher in hypertensive patients (44.4 +/- 5.1 pmol/L vs 21.6 +/- 3.2 pmol/L; p < 0.05 and 271.1 +/- 21.6 pmol/L vs 139.1 +/- 15.2 pmol/L; p < 0.001). Thus, despite under-nutrition, hypertensive Vietnamese patients have a moderate but significant increase in BMI and fat mass without predominant abdominal localization, and a state of insulin-resistance, compared with normotensive healthy subjects.