Insulin Resistance as an Associated Factor of Essential Hypertension in Korean

ABSTRACT

BACKGROUND: The insulin resistance is reported as the independent risk factor of the DM and the ischemic heart disease. The association between the insulin resistance and the essential hypertension was reported at the various countries and races. We performed this study to know if the hypertensive patients show the increased insulin resistance than that of the normotensive persons and factors that influence the insulin resistance and the blood pressure. METHODS: The serum lipid profiles, OGTT, body habitus measurement and abdominal CT at umbilical level were performed in 24 hypertensive patients(male 10, female 14) and 45 normotensive persons(male 19, female 26) who showed the same distributions of age, sex, weight and body mass index(BMI). RESULTS: The average age of the hypertensive group was 49.1+/-7.9 years, and that of the normotensive group was 46.1+/-7.6 years(p>0.05). The average blood pressure of the hypertensive group was 152.2+/-14.2/98.4+/-6.4mmHg and that of the normotensive group was 116.8+/-9.4/78.2+/-49.mmHg(p<0.001). The hypertensive group had significantly higher area under curve(AUC) of glucose(246.8+/-30.4 Vs 219.2+/-32.2mg/dL.hr) and AUC of insulin(88.9+/-38.2 Vs 69.6+/-34.2microU/mL.hr) than the normotensive group(p<0.05), while there were no differences in the age, sex, weight, body mass index(BMI) and waist to hip ratio(WHR) between two groups. They had nodifferences in lipid profile and plasma renin activity. In CT assessment, the hypertensive group had significantly higher visceral fat to thigh muscle area ratio(VSFTM ratio)(0.61+/-0.29 Vs 0.47+/-0.20) and visceral fat to thigh muscle and fat area ratio(VSFTMF ratio)(0.27+/-0.10 Vs 0.22+/-0.13)(p<0.05), while they had same degree of visceral fat to subcutaneous fat area(VS) ratio and visceral fat area. The visceral fat area, VSFTM ratio, VS ratio, visceral fat area to thigh fat area ratio(VSFTF ratio) were positively correlated with AUC of insulin and AUC of glucose ordinary(p<0.05). After adjustment for plasma insulin, AUC of insulin, VS ratio, VSFTM ratio, age and BMI, the AUC of glucose was positively correlated with the diastolic blood pressure(R square=0.19, p <0.05) and the AUC of glucose and WTR were positively correlated with the systolic blood pressure(R square=0.26, p<0.05). THe subgroup over the 75 percentile of AUC of glucose, AUC of insulin and VSFTM ratio in study population had significantly higher odds ratio of the hypertension(OR of AUC of glusose 5.8, OR of AUC of insulin 3.2, OR of VSFTM ratio 4.5, p<0.05). CONCLUSION: These results suggest that the insulin resistance is more prevalent in the hypertensive patients and associated with the hypertension.