Prehypertension is associated with insulin resistance.

BACKGROUND: Prehypertension, a new category of blood pressure (BP) classification introduced by The Seven Report of the Joint National Commission (JNC-7) on High BP for individuals with systolic BP in the range of 120-139 mmHg or diastolic BP between 80 and 89 mmHg, is a strong predictor for the development of hypertension. Insulin resistance (IR) has been proposed to be a key feature of metabolic abnormalities of hypertension and may precede the elevation of BP. AIM: The purpose of the study is to evaluate whether prehypertension is associated with IR. DESIGN: This is a cross-sectional study. METHODS: Anthropometric and BP measurements were performed in 83 prehypertensive subjects and 192 normotensives. All subjects received a 75-g oral glucose tolerance test (OGTT) for the measurements of IR. RESULTS: The prehypertensive subjects were more obese and had higher levels of fasting triglycerides and 2-h insulin than the normotensives. The subjects with prehypertension were more insulin resistant than the counterparts, indicated by lower insulin sensitivity index, ISI(0,120), values. While there was no difference between the two groups in insulin response of OGTT after adjustments for confounders, the prehypertension group maintained significant between-group differences in glucose response even when the incremental insulin levels were added to covariates for adjustments. DISCUSSION: Our data show that prehypertension is associated with IR. The subjects with prehypertension have clinical characteristics of the IR syndrome. It seems that the prehypertension group cannot handle oral glucose challenge as well as the normotension, probably a consequence of IR in prehypertension.

The soluble leptin receptor of regular exercisers.

This study examined the concentrations and the relationships of soluble leptin receptor (sLR) and leptin levels among both physically active people and lean sedentary persons. Information collected for this study came from twelve joggers (JOG), ten weight trainers (WET) and eleven lean sedentary persons (CON). Regular exercisers were defined as those who consistently participated in jogging or weight training 30 minutes a day, at least four times a week, for a period of no less than three years prior to the study. The CON group was defined as exercising, at most, one time per week, less than 20 minutes each time if at all. Leptin and sLR were analyzed using enzyme-linked immunosorbent assay. The results show the BMI of the WET group to be higher than the other groups, yet their percent body fat was not significantly different. Although sLR levels of the JOG group were higher than the WET and CON groups, their free leptin index (FLI) did not show a significant difference. The sLR levels for joggers were higher than the weight trainers. The sLR concentration or the ratio of sLR to fat mass may be an alternative index to FLI for comparing physically active and lean people.

Reference spirometric values in healthy Chinese neversmokers in two townships of Taiwan.

The present community-based study was performed to provide predictive equations and lower boundaries of normal values for forced expiratory volume in one second (FEVI), forced vital capacity (FVC), and their percent ratio (FEV1%) in non-smoking, healthy adult men and women residing in communities, using ATS-recommended techniques and equipment. Use was made of data collected cross-sectionally from Nov. 1990 to Dec. 1993 in an ongoing longitudinal study on evolution of cardiovascular disease risk factors in Chinese. The spirometric values in our population reached their peak at around age 20. After age 20, a downward age trend was observed for FVC, FEV1, and FEV1%. Linear and negative relations were found in adults for each of the three spirometric values with age. Linear and positive relations were found between height and FVC or FEV1, but not between height and FEV1%. The age trends of FVC and FEV1 in Chinese adults were similar to those in Caucasians. Mean FVC and FEV1 levels of Chinese in Taiwan were systematically lower than those of Caucasians for a given height and a given age. Age and height specific percentile values of FVC and FEV1 and the age-specific percentile value of FEV1% are provided for adult men and women in this community study.