Changes in plasma lipids and lipoproteins associated with starting or stopping postmenopausal hormone replacement therapy. Atherosclerosis Risk in Communities Study.

The Atherosclerosis Risk in Communities Study investigators examined nearly 4000 postmenopausal women from 1987 through 1989 and 3 years later to determine changes in plasma lipids occurring with the starting or stopping of hormone replacement therapy. Women who started estrogen plus progestin therapy (n = 74) had decreases of 9.8 mg/dl in low-density lipoprotein (LDL) cholesterol and 5.8 mg/dl in apolipoprotein B and increases of 1.2 mg/dl in high-density lipoprotein (HDL) cholesterol (HDL change not significant), 13.5 mg/dl in apolipoprotein A-I, and 14.0 mg/dl in triglycerides. Women who started estrogen alone (n = 149) had similar changes, except for a much larger increase in HDL cholesterol (5.8 mg/dl), principally in HDL-2. Women who stopped hormone therapy (n = 138) had lipid changes opposite to those who started therapy, but smaller in magnitude. These results confirm those of the Postmenopausal Estrogen/Progestin Interventions Trial in a community-based longitudinal cohort: women initiating estrogen plus progestin therapy have decreases in LDL cholesterol, but the increase in HDL cholesterol is less than that for starting estrogen alone. In addition, the current study extends findings to apolipoproteins and HDL subfractions.

Increase in fasting insulin and glucose over seven years with increasing weight and inactivity of young adults. The CARDIA Study. Coronary Artery Risk Development in Young Adults.

To characterize 7-year changes in fasting serum insulin and glucose concentrations, the authors analyzed population-based data on 3,095 nondiabetic black and white men and women who were initially aged 18-30 years in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Measurements were made of fasting insulin (by an assay with little cross-reactivity to proinsulin) and fasting glucose on frozen samples from baseline and Year 7 examinations. Over the 7-year period, mean fasting insulin increased 10-25%, mean fasting glucose increased 7-10%, and mean body mass increased 7-12% across the four race-, sex-groups. The strongest predictor of both insulin increase and glucose increase was an increase in body mass over the 7 years. Adjusted for age and examination time period in race-, sex-specific repeated measures analyses, fasting insulin increased longitudinally by approximately 5 microU/mL per 5 kg/m2 increase in body mass index (p < 0.05). Adjusted for age and time period, fasting insulin increased over the 7 years by approximately 2.5 microU/mL per 0.08 unit increase in waist/hip ratio (p < 0.05), although this association was much stronger cross-sectionally. In a similar model, each 100 unit decrease in physical activity longitudinally predicted a 0.1-0.2 microU/mL increase in fasting insulin (p < 0.05 in black men only); this association was stronger and statistically significant in all race-, sex-groups cross-sectionally. Fasting insulin was not associated with energy intake either cross-sectionally or longitudinally, but age- and time-adjusted associations of insulin change with change in several nutrients (e.g., energy from fat) were statistically significant in whites. The authors conclude that marked increased in weight in young adulthood adversely alters glucose and insulin metabolism, and that, if not reversed, this may lead to harmful health consequences in later life.