Effect of age on aortic atherosclerosis.

OBJECTIVE: To examine the association of atherosclerosis burden in the survivors of an asymptomatic elderly cohort study and its relationship to other coronary risk factors (specifically, age) by evaluating aortic atherosclerotic wall burden by magnetic resonance imaging (MRI). METHODS: A total of 312 participants in an ongoing observational cohort study underwent cardiac and descending thoracic aorta imaging by MRI. Maximum wall thickness was measured and the mean wall thickness calculated. Wall/outer wall ratio was used as a normalized wall index (NWI) adjusted for artery size difference among participants. Percent wall volume (PWV) was calculated as NWI × 100. RESULTS: IN THIS ASYMPTOMATIC COHORT (MEAN AGE: 76 years), the mean (SD) aortic wall area and wall thickness were 222 ± 45 mm(2) and 2.7 ± 0.4 mm, respectively. Maximum wall thickness was 3.4 ± 0.6 mm, and PWV was 32% ± 4%. Women appeared to have smaller wall area, but after correcting for their smaller artery size, had significantly higher PWV than men (P = 0.03). Older age was associated with larger wall area (P = 0.04 for trend) with similar PWVs. However, there were no statistically significant associations between standard risk factors, Framingham global risk, or metabolic syndrome status, therapy for cholesterol or hypertension, coronary or aortic calcium score, and the aortic wall burden. Aortic calcification was associated with coronary calcification. CONCLUSIONS: Asymptomatic elderly in this cohort had a greater descending thoracic aortic wall volume that correlated with age, and women had a significantly increased PWV compared to men. In these survivors, the atherosclerotic aortic wall burden was not significantly associated with traditional risk factors or with coronary or aortic calcium scores or coronary calcium progression. Results suggest that age, or as yet unidentified risk factor(s), may be responsible for the increase in atherosclerosis.

Value of measuring muscle performance to assess changes in lean mass with testosterone and growth hormone supplementation.

We hypothesized that treatment with testosterone (T) and recombinant human growth hormone (rhGH) would increase lean mass (LM) and muscle strength proportionally and an in a linear manner over 16 weeks. This was a multicenter, randomized, controlled, double-masked investigation of T and rhGH supplementation in older (71 ± 4 years) community-dwelling men. Participants received transdermal T at either 5 or 10 g/day as well as rhGH at 0, 3.0 or 5.0 µg/kg/day for 16 weeks. Body composition was determined by dual-energy X-ray absorptiometry (DEXA) and muscle performance by composite one-repetition maximum (1-RM) strength and strength per unit of lean mass (muscle quality, MQ) for five major muscle groups (upper and lower body) at baseline, week 8 and 17. The average change in total LM at study week 8 compared with baseline was 1.50 ± 1.54 kg (P < 0.0001) in the T only group and 2.64 ± 1.7 (P < 0.0001) in the T + rhGH group and at week 17 was 1.46 ± 1.48 kg (P < 0.0001) in the T only group and 2.14 ± 1.96 kg (P < 0.0001) in the T + rhGH group. 1-RM strength improved modestly in both groups combined (12.0 ± 23.9%, P < 0.0001) at week 8 but at week 17 these changes were twofold greater (24.7 ± 31.0%, P < 0.0001). MQ did not significantly change from baseline to week 8 but increased for the entire cohort, T only, and T + rhGH groups by week 17 (P < 0.001). Despite sizeable increases in LM measurements at week 8, tests of muscle performance did not show substantive improvements at this time point.

Whole-body and muscle protein metabolism are not affected by acute deviations from habitual protein intake in older men: the Hormonal Regulators of Muscle and Metabolism in Aging (HORMA) Study.

BACKGROUND: Acute deviations in protein intake before the quantification of protein kinetics in older humans may explain the controversy over the effects of older age on muscle protein synthesis and proteolysis rates. OBJECTIVE: We hypothesized that an acute decrease in protein intake from the habitual intake is associated with lower muscle protein synthesis and higher proteolysis rates, whereas an acute increase in protein intake from the habitual intake is associated with higher muscle protein synthesis and lower proteolysis rates. DESIGN: In 112 community-dwelling healthy men aged 65-90 y, we quantified resting whole-body [1,2-(13)C(2)]leucine kinetics, muscle mixed protein fractional synthesis rates (FSRs), and muscle proteasome proteolytic enzyme activities after participants consumed for 3 d controlled research meals (0.9-1.1 g protein · kg(-1) · d(-1)) that contained more or less protein than that habitually consumed and that induced alterations in nitrogen balance. RESULTS: Protein kinetic parameters were not significantly different between the groups, despite controlled research protein intakes that were lower (-0.2 to -0.3 g · kg(-1) · d(-1)) or higher (+0.2 g · kg(-1) · d(-1)) than habitual intakes and that induced negative (-22 to -25 mg · kg(-1) · d(-1)) or positive (22-25 mg · kg(-1) · d(-1)) nitrogen balance. Within these acutely altered protein intake and nitrogen balance boundaries, a reduction in protein intake from habitual intake and induction of negative nitrogen balance were not associated with higher proteolysis or lower muscle FSR, and an acute increase in protein intake from habitual intake and induction of positive nitrogen balance were not associated with lower proteolysis or higher muscle FSR. A higher quantitative insulin sensitivity check index was associated with lower whole-body proteolysis rates. CONCLUSIONS: The practice of acutely controlling protein intake, even at intakes lower than habitual intakes that induce negative nitrogen balance, before quantifying human protein kinetics does not significantly reduce muscle protein synthesis or increase proteolysis. Factors other than protein intake explain lower muscle protein synthesis rates with advanced age. This trial is registered at clinicaltrials.gov as NCT00183040.

Durability of the effects of testosterone and growth hormone supplementation in older community-dwelling men: the HORMA Trial.

OBJECTIVES: To determine the durability of anabolic effects and adverse events (AEs) after stopping testosterone and growth hormone supplementation in older men. DESIGN: Secondary analysis of a double-masked, randomized controlled trial of testosterone gel (5 or 10 g/daily) plus rhGH (0, 3 or 5 µg/kg/day) with follow-up of outcomes 3 months later. PARTICIPANTS: A total of 108 community-dwelling 65- to 90-year-old men. MEASUREMENTS: Testosterone and IGF-1 levels, body composition (DEXA), 1-repetition maximum (1-RM) strength, stair-climbing power, quality-of-life (QOL) and activity questionnaires, AEs. RESULTS: Despite improvements in body composition during treatment, residual benefits 3 months later (week 28) were variable. For participants with improvements exceeding their week-17 median changes, benefits were sustained at week 28 for lean body mass (1·45 ± 1·63 kg, 45% of week-17 values, P < 0·0001 vs baseline), appendicular skeletal muscle mass (ASMM, 0·71 ± 1·01 kg, 42%, P < 0·0001), total fat (-1·06 ± 2·18 kg, 40%, P < 0·0001) and trunk fat (-0·89 ± 1·42 kg, 50%, P < 0·0001); retention of ASMM was associated with greater week-16 protein intake (P = 0·01). For 1-RM strength, 39%-43% of week-17 improvements (P ≤ 0·05) were retained and associated with better week-17 strength (P < 0·0001), change in testosterone from week 17-to 28 (P = 0·004) and baseline PASE (P = 0·04). Framingham 10-year cardiovascular risks were low (~14%), did not worsen and improved by week 28 (P = 0·0002). The hypothalamic-pituitary-gonadal axis recovered completely. CONCLUSIONS: Durable improvements in muscle mass, strength and fat mass were retained 3 months after discontinuing hormone supplementation in participants with greater than median body composition changes during treatment, but not in others with smaller gains. AEs largely resolved after intervention discontinuation. Additional strategies may be needed to sustain or augment muscle mass and strength gains achieved during short-term hormone therapy.

Testosterone threshold levels and lean tissue mass targets needed to enhance skeletal muscle strength and function: the HORMA trial.

BACKGROUND: In the HORMA (Hormonal Regulators of Muscle and Metabolism in Aging) Trial, supplemental testosterone and recombinant human growth hormone (rhGH) enhanced lean body mass, appendicular skeletal muscle mass, muscle performance, and physical function, but there was substantial interindividual variability in outcomes. METHODS: One hundred and twelve men aged 65-90 years received testosterone gel (5 g/d vs 10 g/d via Leydig cell clamp) and rhGH (0 vs 3 vs 5 µg/kg/d) in a double-masked 2 × 3 factorial design for 16 weeks. Outcomes included lean tissue mass by dual energy x-ray absorptiometry, one-repetition maximum strength, Margaria stair power, and activity questionnaires. We used pathway analysis to determine the relationship between changes in hormone levels, muscle mass, strength, and function. RESULTS: Increases in total testosterone of 1046 ng/dL (95% confidence interval = 1040-1051) and 898 ng/dL (95% confidence interval = 892-904) were necessary to achieve median increases in lean body mass of 1.5 kg and appendicular skeletal muscle mass of 0.8 kg, respectively, which were required to significantly enhance one-repetition maximum strength (≥ 30%). Co-treatment with rhGH lowered the testosterone levels (quantified using liquid chromatography-tandem mass spectrometry) necessary to reach these lean mass thresholds. Changes in one-repetition maximum strength were associated with increases in stair climbing power (r = .26, p = .01). Pathway analysis supported the model that changes in testosterone and insulin-like growth factor 1 levels are related to changes in lean body mass needed to enhance muscle performance and physical function. Testosterone's effects on physical activity were mediated through a different pathway because testosterone directly affected Physical Activity Score of the Elderly. CONCLUSIONS: To enhance muscle strength and physical function, threshold improvements in lean body mass and appendicular skeletal muscle mass are necessary and these can be achieved by targeting changes in testosterone levels. rhGH augments the effects of testosterone. To maximize functional improvements, the doses of anabolic hormones should be titrated to achieve target blood levels.

Does coronary calcium score predict future cardiac function? Association of subclinical atherosclerosis with left ventricular systolic and diastolic dysfunction at MR imaging in an elderly cohort.

PURPOSE: To evaluate subclinical atherosclerosis measured by using coronary artery calcium (CAC) as a predictor of future left ventricular (LV) systolic and diastolic function in asymptomatic elderly participants. MATERIALS AND METHODS: The institutional review boards of the University of Southern California and the Harbor University of California Los Angeles Research and Education Institute (where the South Bay Heart Watch study was initially conducted) approved this HIPAA-compliant study of 386 participants (mean age, 75.2 years) from among the original 1461 participants in the longitudinal South Bay Heart Watch prospective investigation of subclinical atherosclerosis. CAC at computed tomography was correlated with LV ejection fraction (LVEF), regional wall motion abnormalities (RWMAs), and peak filling rate (PFR) assessed a mean of 11.4 years ± 0.6 (standard deviation) later with cardiac magnetic resonance imaging. Analysis of variance and covariance testing was performed with the Wald test, testing for trends across the CAC groups. Covariates included age, level of total cholesterol, level of high-density lipoprotein cholesterol, systolic blood pressure, use of lipid-lowering medication, and smoking status. RESULTS: Mean LVEF was 60.3% ± 9.9, with 11 (2.8%) of 386 participants having an LVEF of less than 40%. Forty-six (11.9%) of 386 participants had RWMAs. Higher CAC scores were associated with slightly lower LVEF (P for trend = .04) and a greater percentage of participants with decreased PFR (P for trend = .47) and RWMAs (P for trend = .01). After age- and risk factor-adjustment, only RWMA (P = .05) was associated with higher CAC. RWMAs were associated with significantly (P < .001) lower mean LVEF and PFR. Nineteen (41%) of 46 participants with RWMAs had documented Q-wave myocardial infarction, and three (7%) underwent coronary revascularization. CAC scores of 100 or greater were associated with a 2.2-fold (95% confidence interval: 1.30, 3.75) increase in RWMA (P < .001). CONCLUSION: Subclinical atherosclerosis assessed by using CAC is associated with an increased future likelihood of RWMA, as a marker of previous and possible subclinical coronary artery disease.

Declining beta-cell compensation for insulin resistance in Hispanic women with recent gestational diabetes mellitus: association with changes in weight, adiponectin, and C-reactive protein.

OBJECTIVE: To identify factors associated with declining beta-cell compensation for insulin resistance. RESEARCH DESIGN AND METHODS: In a cohort of Hispanic women with recent gestational diabetes mellitus, oral glucose tolerance tests (OGTTs), intravenous glucose tolerance tests (IVGTTs), and bioelectrical impedance measurements were performed at 15-month intervals for up to 5 years, or until fasting plasma glucose exceeded 140 mg/dl (7.8 mmol/l). Data were analyzed to identify predictors of declining beta-cell compensation for insulin resistance (the disposition index [DI]) and to examine the mechanism of weight gain and changes in circulating levels of selected adipokines and inflammatory markers on beta-cell compensation decline. RESULTS: A total of 60 nondiabetic women had a median of four sets of OGTT + IVGTT during a median follow-up of 52 months. Fourteen of the women developed diabetes. None of the baseline characteristics were significantly predictive of a decline in DI. There were significant univariate associations between declining DI and weight gain (specifically fat gain), declining adiponectin and rising C-reactive protein. Multivariate analysis showed that the weight gain was the most significant factor associated with declining DI. The amount of association between weight gain and declining DI was explained 31% by changes in adiponectin and C-reactive protein and 40% by changes in insulin resistance. CONCLUSIONS: These results identify weight gain as the strongest factor associated with declining beta-cell compensation for insulin resistance in Hispanic women at high risk for type 2 diabetes. Such effect may be mediated through at least two effects: alterations in adipokine levels and increasing insulin resistance.

N-terminal propeptide of type III procollagen as a biomarker of anabolic response to recombinant human GH and testosterone.

CONTEXT: Biomarkers that predict musculoskeletal response to anabolic therapies should expedite drug development. During collagen synthesis in soft lean tissue, N-terminal propeptide of type III procollagen (P3NP) is released into circulation. We investigated P3NP as a biomarker of lean body mass (LBM) and muscle strength gains in response to testosterone and GH. DESIGN: Community-dwelling older men received GnRH agonist plus 5 or 10 g testosterone gel plus 0, 3, or 5 microg recombinant human GH daily. P3NP levels were measured at baseline and wk 4, 8, 12, and 16. LBM and appendicular skeletal muscle mass (ASM) were measured by dual-energy x-ray absorptiometry. RESULTS: One hundred twelve men completed treatment; 106 underwent serum P3NP measurements. P3NP levels were higher at wk 4 than baseline (6.61 +/- 2.14 vs. 4.51 +/- 1.05, P < 0.0001) and reached plateau by wk 4 in men receiving testosterone alone. However, wk 8 P3NP levels were higher than wk 4 levels in men receiving testosterone plus recombinant human GH. Increases in P3NP from baseline to wk 4 and 16 were significantly associated with gains in LBM (r = 0.26, P = 0.007; r = 0.53, P < 0.001) and ASM (r = 0.17, P = 0.07; r = 0.40, P < 0.0001). Importantly, for participants receiving only testosterone, P3NP increases at wk 4 and 16 were related to muscle strength gains (r = 0.20, P = 0.056 and r = 0.36, P = 0.04). In stepwise regression, change in P3NP explained 28 and 30% of the change in ASM and LBM, respectively, whereas change in testosterone but not IGF-I and age provided only small improvements in the models. CONCLUSION: Early changes in serum P3NP levels are associated with subsequent changes in LBM and ASM during testosterone and GH administration. Serum P3NP may be a useful early predictive biomarker of anabolic response to GH and testosterone.

Additive effects of genetic variation in GCK and G6PC2 on insulin secretion and fasting glucose.

OBJECTIVE: Glucokinase (GCK) and glucose-6-phosphatase catalytic subunit 2 (G6PC2) regulate the glucose-cycling step in pancreatic beta-cells and may regulate insulin secretion. GCK rs1799884 and G6PC2 rs560887 have been independently associated with fasting glucose, but their interaction on glucose-insulin relationships is not well characterized. RESEARCH DESIGN AND METHODS: We tested whether these variants are associated with diabetes-related quantitative traits in Mexican Americans from the BetaGene Study and attempted to replicate our findings in Finnish men from the METabolic Syndrome in Men (METSIM) Study. RESULTS: rs1799884 was not associated with any quantitative trait (corrected P > 0.1), whereas rs560887 was significantly associated with the oral glucose tolerance test 30-min incremental insulin response (30' Deltainsulin, corrected P = 0.021). We found no association between quantitative traits and the multiplicative interaction between rs1799884 and rs560887 (P > 0.26). However, the additive effect of these single nucleotide polymorphisms was associated with fasting glucose (corrected P = 0.03) and 30' Deltainsulin (corrected P = 0.027). This additive association was replicated in METSIM (fasting glucose, P = 3.5 x 10(-10) 30' Deltainsulin, P = 0.028). When we examined the relationship between fasting glucose and 30' Deltainsulin stratified by GCK and G6PC2, we noted divergent changes in these quantitative traits for GCK but parallel changes for G6PC2. We observed a similar pattern in METSIM. CONCLUSIONS: Our data suggest that variation in GCK and G6PC2 have additive effects on both fasting glucose and insulin secretion.

Testosterone and growth hormone improve body composition and muscle performance in older men.

CONTEXT: Impairments in the pituitary-gonadal axis with aging are associated with loss of muscle mass and function and accumulation of upper body fat. OBJECTIVES: We tested the hypothesis that physiological supplementation with testosterone and GH together improves body composition and muscle performance in older men. DESIGN, SETTING, AND PARTICIPANTS: One hundred twenty-two community-dwelling men 70.8 +/- 4.2 yr of age with body mass index of 27.4 +/- 3.4 kg/m2, testosterone of 550 ng/dl or less, and IGF-I in lower adult tertile (< or =167 ng/dl) were randomized to receive transdermal testosterone (5 or 10 g/d) during a Leydig cell clamp plus GH (0, 3, or 5 microg/kg . d) for 16 wk. MAIN OUTCOME MEASURES: Body composition by dual-energy x-ray absorptiometry, muscle performance, and safety tests were conducted. RESULTS: Total lean body mass increased (1.0 +/- 1.7 to 3.0 +/- 2.2 kg) as did appendicular lean tissue (0.4 +/- 1.4 to 1.5 +/- 1.3 kg), whereas total fat mass decreased by 0.4 +/- 0.9 to 2.3 +/- 1.7 kg as did trunk fat (0.5 +/- 0.9 to 1.5 +/- 1.0 kg) across the six treatment groups and by dose levels for each parameter (P < or = 0.0004 for linear trend). Composite maximum voluntary strength of upper and lower body muscles increased by 14 +/- 34 to 35 +/- 31% (P < 0.003 in the three highest dose groups) that correlated with changes in appendicular lean mass. Aerobic endurance increased in all six groups (average 96 +/- 137 sec longer). Systolic and diastolic blood pressure increased similarly in each group with mean increases of 12 +/- 14 and 8 +/- 8 mm Hg, respectively. Other predictable adverse events were modest and reversible. CONCLUSIONS: Supplemental testosterone produced significant gains in total and appendicular lean mass, muscle strength, and aerobic endurance with significant reductions in whole-body and trunk fat. Outcomes appeared to be further enhanced with GH supplementation.

[A case of ulcerative colitis with preexisting idiopathic thrombocytopenic purpura].

A 53-year-old man was diagnosed as having idiopathic thrombocytopenic purpura (ITP). Hematochezia appeared under steroid therapy for ITP after the diagnosis of ITP 18 months. Colonoscopic study demonstrated inflamed rectal mucosa but there was no evidence of infectious colitis. The colonoscopic and pathological findings were compatible with ulcerative colitis (UC). There have been a few reports of patients with UC complicated by ITP, but in all except one report, UC preceded ITP. This is the third case in which ITP preceded UC and the first case in which the proctitis type of UC was complicated by ITP in Japan.

Effect of pioglitazone on progression of subclinical atherosclerosis in non-diabetic premenopausal Hispanic women with prior gestational diabetes.

The Pioglitazone in the Prevention of Diabetes (PIPOD) study was a single arm 3-year open-label pioglitazone treatment to determine the effects of pioglitazone in women with prior gestational diabetes mellitus (GDM) who had completed the troglitazone in the Prevention of Diabetes (TRIPOD) study. Here we report the results on progression of subclinical atherosclerosis, measured by carotid intima-media thickness (CIMT) in non-diabetic women. Data were analyzed to compare CIMT progression rates during pioglitazone treatment to rates that had been observed during either placebo or troglitazone treatment in the TRIPOD study. Sixty-one women met the entry criteria with mean age of 40 years. In the 30 women who came to PIPOD from the placebo arm of TRIPOD, the CIMT rate was 69% lower during pioglitazone treatment than it had been during placebo (0.0031 vs. 0.0100mm/yr, p=0.006). In the 31 women who came to PIPOD from the troglitazone arm of TRIPOD, CIMT rate was 38% lower during pioglitazone than it had been during troglitazone, a difference that was not statistically significant (0.0037 vs. 0.0060mm/year; p=0.26). Adjustment for differences in baseline characteristics and potential on-trial confounders did not alter the conclusion but did increase the CIMT rates differences slightly. We conclude that treatment with pioglitazone slowed CIMT progression in women who had been on placebo in the TRIPOD study and maintained a relatively low rate of progression in women who had been on troglitazone. Pioglitazone slows progression of subclinical atherosclerosis in young Hispanic women at increased risk for type 2 diabetes.

Hormonal regulators of muscle and metabolism in aging (HORMA): design and conduct of a complex, double masked multicenter trial.

BACKGROUND: Older persons often lose muscle mass, strength, and physical function. This report describes the challenges of conducting a complex clinical investigation assessing the effects of anabolic hormones on body composition, physical function, and metabolism during aging. METHODS: HORMA is a multicenter, randomized double masked study of 65-90-year-old community dwelling men with testosterone levels of 150-550 ng/dL and IGF-1 < 167 ng/dL. Subjects were randomized to transdermal testosterone (5 or 10 g/day) and rhGH (0, 3, or 5 microg/kg/day) for 16 weeks. Outcome measures included body composition by DEXA, MRI, and (2)H(2)O dilution; muscle performance (strength, power, and fatigability), VO2peak, measures of physical function, synthesis/breakdown of myofibrillar proteins, other measures of metabolism, and quality of life. RESULTS: Major challenges included delay in startup caused by need for 7 institutional contracts, creating a 142-page manual of operations, orientation and training, creating a 121-page CRF; enrollment inefficiencies; scheduling 16 evaluations/ subject; overnight admissions for invasive procedures and isotope infusions; large data and image management and transfer; quality control at multiples sites; staff turnover; and replacement of a clinical testing site. Impediments were largely solved by implementation of a web-based data entry and eligibility verification; electronic scheduling for multiple study visits; availability of research team members to educate and reassure subjects; more frequent site visits to validate all source documents and reliability of data entry; and intensifying quality control in testing and imaging. The study exceeded the target goal of 108 (n = 112) completely evaluable cases. Two interim DSMB meetings confirmed the lack of excessive adverse events, lack of center effects, comparability of subjects, and that distribution of subjects and enrollment will not jeopardize outcomes or generalizability of results. CONCLUSIONS: Flexibility and rapidly solving evolving problems is critical when conducting highly complex multicenter metabolic studies.

A longitudinal study of lipids and blood pressure in relation to method of contraception in Latino women with prior gestational diabetes mellitus.

OBJECTIVE: To investigate the effect of nonhormonal contraception (NHC), combination oral contraception (COC), and depo-medroxyprogesterone acetate (DMPA) on lipids and blood pressure in women with recent gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS: An observational cohort of 972 nondiabetic, normotensive, postpartum Latino women who elected NHC (n = 448), COC (n = 430), or DMPA (n = 94) were followed for at least one subsequent metabolic evaluation on the same contraception. Baseline and follow-up measures included glucose tolerance testing, fasting serum LDL and HDL cholesterol, triglycerides, and systolic (SBP) and diastolic (DBP) blood pressure. Patterns of changes in lipids and blood pressure were evaluated by comparing slopes over follow-up time using random coefficient linear mixed-effects models. RESULTS: Median follow-up times were 20, 12, and 11 months in the NHC, COC, and DMPA groups. The DMPA users gained significantly more weight (4.3 +/- 6.9 kg/year) compared with NHC and COC users (1.2 +/- 4.7 and 0.7 +/- 6.0 kg/year, respectively; P < 0.0001). Patterns of change in LDL cholesterol, triglycerides, and DBP were not significantly different among groups. HDL cholesterol change differed only between COC and NHC groups (adjusted slopes: 1.0 vs. -1.6 mg x dl(-1) x year(-1), respectively; P < 0.0001). SBP change differed only between COC and DMPA groups (adjusted slopes: 1.3 vs. -1.7 mmHg/year, respectively; P = 0.01). CONCLUSIONS: These results, derived predominantly from the initial 1-2 years of treatment in Hispanic women, demonstrate that DMPA was associated with greater weight gain than NHCs or COCs. Other differences in blood pressure and lipid effects were very small. These findings should be taken into account when advising women with recent GDM about their contraceptive choices.

Reliability of maximal voluntary muscle strength and power testing in older men.

BACKGROUND: Maximal voluntary muscle strength (MVMS) and leg power are important measures of physical function in older adults. We hypothesized that performing these measures twice within 7-10 days would demonstrate a >5% increase due to learning and familiarization of the testing procedures. METHODS: Data were collected from three studies in older adult men (60-87 years) and were divided into two cohorts defined by study site and type of exercise equipment. MVMS was assessed in 116 participants using the one-repetition maximum method at two separate study visits for the chest press, latissimus pull-down, leg press, leg flexion, and leg extension exercises along with unilateral leg extension power. RESULTS: Test-retest scores were not different and did not exceed 0.8 +/- 9.0% in Cohort 1 or 2.3 +/- 9.8% in Cohort 2, except for leg extension, which improved by 6.6 +/- 14.4% (p <.009) and 3.4 +/- 6.8% (p <.016), respectively. Repeat tests were closely correlated with initial tests (all p <.001). Pearson correlation coefficients ranged from 0.74 for leg extension power to 0.96 for leg press. Coefficients of variation were <10% (4.2%-9.0%) for all exercises except for leg extension power, which was 15.5%. CONCLUSIONS: Our findings demonstrated that test-retest measures of MVMS and power in older adult men do not differ by more than 2.3% except for leg extension, and have relatively low coefficients of variation using data collected from three studies. Moreover, these findings were similar between two study sites using different equipment, which further supports the reliability of MVMS and power testing in older adult men.

Long-acting injectable progestin contraception and risk of type 2 diabetes in Latino women with prior gestational diabetes mellitus.

OBJECTIVE: To investigate the impact of a long-acting injectable progestin, depo-medroxyprogesterone acetate (DMPA), compared with combination oral contraceptives (COCs) on the risk of diabetes in Latino women with prior gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS: An observational cohort study of 526 Hispanic women with prior GDM who were not diabetic in their postpartum visit during January 1987 to October 1997 and who elected DMPA (n = 96) or COCs (n = 430) as initial contraception were followed for a maximum of 9.2 years with a median follow-up of approximately 12 months. Oral glucose tolerance tests were performed and choice of contraception method was recorded at each visit as part of routine clinical care. RESULTS: Annual diabetes incidence rates were 19% in the DMPA group and 12% in the COC group, with an unadjusted hazard ratio (HR) of 1.58 (95% CI 1.00-2.50; P = 0.05) for DMPA compared with COCs. Adjustment for baseline imbalances reduced the HR to 1.18 (0.67-2.28; P = 0.57). Additional adjustment for weight gain during follow-up, which was on average 1.8 kg higher in the DMPA group (P < 0.0001), reduced the HR to 1.07. DMPA interacted with baseline serum triglyceride levels and, separately, with breast-feeding to increase the diabetes risk. CONCLUSIONS: DMPA use was associated with an increased risk of diabetes that appeared to be explained by three factors: 1) use in women with increased baseline diabetes risk, 2) weight gain during use, and 3) use with high baseline triglycerides and/or during breast-feeding.

Effect of pioglitazone on pancreatic beta-cell function and diabetes risk in Hispanic women with prior gestational diabetes.

The Pioglitazone In Prevention Of Diabetes (PIPOD) study was conducted to evaluate beta-cell function, insulin resistance, and the incidence of diabetes during treatment with pioglitazone in Hispanic women with prior gestational diabetes who had completed participation in the Troglitazone In Prevention Of Diabetes (TRIPOD) study. Women who completed the TRIPOD study were offered participation in the PIPOD study for a planned 3 years of drug treatment and 6 months of postdrug washout. Oral glucose tolerance tests were performed annually on pioglitazone and at the end of the postdrug washout. Intravenous glucose tolerance tests (IVGTTs) for assessment of insulin sensitivity and beta-cell function were conducted at baseline, after 1 year on pioglitazone, and at the end of the postdrug washout. Of 95 women who were not diabetic at the end of the TRIPOD study, 89 enrolled in the PIPOD study, 86 completed at least one follow-up visit, and 65 completed all study visits, including the postdrug tests. Comparison of changes in beta-cell compensation for insulin resistance across the TRIPOD and PIPOD studies revealed that pioglitazone stopped the decline in beta-cell function that occurred during placebo treatment in the TRIPOD study and maintained the stability of beta-cell function that had occurred during troglitazone treatment in the TRIPOD study. The risk of diabetes, which occurred at an average rate of 4.6% per year, was lowest in women with the largest reduction in total IVGTT insulin area after 1 year of treatment. The similarity of findings between the PIPOD and TRIPOD studies support a class effect of thiazolidinedione drugs to enhance insulin sensitivity, reduce insulin secretory demands, and preserve pancreatic beta-cell function, all in association with a relatively low rate of type 2 diabetes, in Hispanic women with prior gestational diabetes.

Race-ethnic differences in the extent, prevalence, and progression of coronary calcium.

OBJECTIVE: To compare across four race-ethnic groups the baseline prevalence and extent of coronary calcium and the 7-year rate of progression in the extent of coronary calcium. DESIGN: The South Bay Heart Watch is a prospective cohort study designed to appraise the value of coronary calcium for predicting cardiovascular outcomes in asymptomatic adults with cardiac risk factors. Statistical analyses were conducted to evaluate ethnic differences in the prevalence, extent, and progression of coronary calcium among Caucasian, African-American, Hispanic, and Asian participants. SETTING: Population-based study. PATIENTS OR PARTICIPANTS: Between December 1990 and December 1992, 1289 participants without coronary heart disease underwent baseline risk factor screening and computed tomography for coronary calcification (Cohort 1). Seven years later, 828 (64%) participants returned for follow-up evaluation and re-scanning (Cohort 2). MAIN OUTCOME MEASURES: Prevalence, extent, and progression of coronary artery calcium. RESULTS: In Cohort 2, compared to Whites, African Americans had a lower prevalence of coronary calcium at baseline (P=.012) and follow-up (P=.005), smaller calcium scores at baseline (P=.005) and follow-up (P=.0004), and less progression (P=.001); Hispanics had a lower prevalence of coronary calcium at follow-up (P=.04) with smaller calcium scores (P=.011), and less progression (P=.009). In contrast, no differences were seen between Whites and Asian/Pacific Islanders. Race-ethnic differences in progression persisted after adjusting for risk factors and participation bias (P<.05). CONCLUSIONS: The present results lend further credence to the notion that race-ethnic differences exist in the prevalence and rate of progression of coronary calcification. The relationship between calcification and the incidence of coronary heart disease in these race-ethnic groups needs further exploration.

Relation of coronary calcium progression and control of lipids according to National Cholesterol Education Program guidelines.

Tracking of coronary artery calcium (CAC) has been suggested for monitoring the effects of lipid control, but it is not known whether lipid control decreases progression of CAC. Seven hundred sixty-one subjects (mean age 64.5 +/- 7.3 years; 91% men; 69% positive for CAC) in an ongoing cohort study underwent baseline and follow-up (after 7.0 +/- 0.5 years) computed tomography for CAC. Subjects were stratified into low-risk (<2 risk factors), intermediate-risk (> or =2 risk factors but <20% risk of coronary heart disease over 10 years), or high-risk (> or =2 risk factors and >20% risk of coronary heart disease in 10 years or diabetes) groups. Lipid control was defined according to criteria of the National Cholesterol Education Program. Two-way analysis of covariance was used to examine the relation of low-density lipoprotein (LDL) cholesterol and risk group to change in CAC volume score. Control of levels of high-density lipoprotein (HDL) cholesterol and triglycerides was also examined in relation to progression of CAC. After adjustment for other risk factors and baseline CAC volume, CAC progression was similar between those with adequate and those with inadequate control of LDL cholesterol (p = 0.68) and across categories of optimal, intermediate, and higher risk LDL cholesterol (p = 0.40). However, higher levels of HDL cholesterol (> or =1.5 mmol/L [60 mg/dl]) were associated with less progression of CAC volume (151 vs 203 mm(3) in those with HDL cholesterol <1.0 mmol/L [40 mg/dl], p = 0.03). There was no relation between triglycerides and CAC progression (p = 0.54). Our findings do not support the use of CAC assessment for monitoring the control of LDL cholesterol, but greater progression of CAC may occur in those in whom HDL cholesterol is not controlled.

Comparison of calcium scores from thick- and thin image slice-computed tomography scanning in predicting future coronary events.

Computed tomographic image slices between 2.5 and 3.0 mm are commonly used for coronary calcium scanning. To evaluate the comparative accuracy of thicker image slices (5 to 6 mm) for predicting coronary events, we acquired both types of scans in 280 research participants and clinically followed them up for 7 years. We found that thick-slice image scanning and image assessment ranked calcium scores similarly and that measurements from both scanning methods predicted coronary heart disease events equally.