Factor analysis has previously identified four independent factors that characterize the insulin resistance syndrome in women, interpreted as 1) weight/waist, 2) lipids, 3) insulin/glucose, and 4) systolic and diastolic blood pressure. Because it is not known whether similar factors emerge for men, or for diabetics, factor analysis was used to investigate the clustering of features characterizing the insulin resistance syndrome using data from 3,159 elderly (71-93 years) Japanese-American men participating in the fourth examination of the Honolulu Heart Program during 1991-1993. Consistent with previous results, factor analysis reduced eight risk factors (insulin, glucose, systolic blood pressure, diastolic blood pressure, triglycerides, high-density lipoprotein cholesterol, weight, and waist circumference) to four uncorrelated factors that explained 78.2% and 74.7% of the variance in nondiabetics (n = 2,760) and diabetics (n = 399), respectively. These factors were interpreted as 1) weight/waist, 2) blood pressure, 3) lipids, and 4) insulin/glucose. Modest differences in the associations between fasting insulin and factors 1, 3, and 4 were noted for diabetics. These consistently identified composite factors may represent markers for underlying pathophysiologic mechanisms of the insulin resistance syndrome and risk of non-insulin-dependent diabetes mellitus.

San Francisco bus drivers have an increased prevalence of hypertension. This study examined relationships between blood lead concentration and blood pressure in 342 drivers. The analysis reported in this study was limited to subjects not on treatment for hypertension (n = 288). Systolic and diastolic pressures varied from 102 to 173 mm Hg and from 61 to 105 mm Hg, respectively. The blood lead concentration varied from 2 to 15 micrograms/dL. The relationship between blood pressure and the logarithm of blood lead concentration was examined using multiple regression analysis. Covariates included age, body mass index, sex, race, and caffeine intake. The largest regression coefficient relating systolic blood pressure and blood lead concentration was 1.8 mm Hg/ln (micrograms/dL) [90% C. I., -1.6, 5.3]. The coefficient for diastolic blood pressure was 2.5 mm Hg/ln (micrograms/dL) [90% C. I., 0.1, 4.9]. These findings suggest effects of lead exposure at lower blood lead concentrations than those concentrations that have previously been linked with increases in blood pressure.