Comparison of methods for delivering a lifestyle modification program for obese patients: a randomized trial.

BACKGROUND: Physicians frequently prescribe medications for weight loss but offer minimal lifestyle counseling despite the additional benefits of combining both interventions. OBJECTIVE: To compare 5 methods of delivering a lifestyle modification program to obese patients receiving sibutramine. DESIGN: Randomized, 6-month, open-label study. Participants were assigned to intervention groups by using a computer-generated schedule of randomly permuted blocks. Block length was 5. SETTING: 12 independent research clinics with experience running obesity trials. PATIENTS: 376 patients with obesity (body mass index > or =30 and <40 kg/m(2)). INTERVENTION: High-frequency face-to-face lifestyle modification counseling (HF-F2F) (n = 74), low-frequency face-to-face counseling (LF-F2F) (n = 76), high-frequency telephone counseling (HF-TEL) (n = 76), high-frequency e-mail counseling (HF-EMAIL) (n = 74), or no dietitian contact (self-help [SELF]) (n = 76). All participants received sibutramine, 10 mg/d; a lifestyle manual; and access to a weight-loss Web site. MEASUREMENTS: Percentage change in body weight at 6 months was the primary outcome. Secondary end points included changes in waist circumference; lipid, glucose, and insulin levels; blood pressure; weight-related symptoms; and quality of life at 6 months. RESULTS: At 6 months, the mean weight loss, relative to baseline, in the HF-F2F and HF-TEL groups was similar (8.9% [95% CI, 8.0% to 9.8%] and 7.7% [CI, 6.8% to 8.7%]) and significantly greater than that in the other groups (LF-F2F, 6.4% [CI, 5.4% to 7.3%]; HF-EMAIL, 5.9% [CI, 5.0% to 6.8%]; and SELF, 5.2% [CI, 4.3% to 6.1%]). All groups showed significant improvements in waist circumference, high-density lipoprotein cholesterol and triglyceride levels, and measures of quality of life and weight-related symptoms. There were no serious adverse events and no differences in minor events among groups. LIMITATION: Most participants were women, and the attrition rate was 30%. CONCLUSION: High-frequency telephone contact with a dietitian was similar to HF-F2F contact for supporting lifestyle modification in obese patients trying to lose weight. The findings might be used by providers and health systems to promote healthy lifestyle changes for their patients. FUNDING: Pfizer Global Research and Development.

Effects of cholesteryl ester transfer protein inhibition on apolipoprotein A-II-containing HDL subspecies and apolipoprotein A-II metabolism.

This study was designed to establish the mechanism responsible for the increased apolipoprotein (apo) A-II levels caused by the cholesteryl ester transfer protein inhibitor torcetrapib. Nineteen subjects with low HDL cholesterol (<40 mg/dl), nine of whom were also treated with 20 mg of atorvastatin daily, received placebo for 4 weeks, followed by 120 mg of torcetrapib daily for the next 4 weeks. Six subjects in the nonatorvastatin cohort participated in a third phase, in which they received 120 mg of torcetrapib twice daily for 4 weeks. At the end of each phase, subjects underwent a primed-constant infusion of [5,5,5-(2)H(3)]L-leucine to determine the kinetics of HDL apoA-II. Relative to placebo, torcetrapib significantly increased apoA-II concentrations by reducing HDL apoA-II catabolism in the atorvastatin (-9.4%, P < 0.003) and nonatorvastatin once- (-9.9%, P = 0.02) and twice- (-13.2%, P = 0.02) daily cohorts. Torcetrapib significantly increased the amount of apoA-II in the alpha-2-migrating subpopulation of HDL when given as monotherapy (27%, P < 0.02; 57%, P < 0.003) or on a background of atorvastatin (28%, P < 0.01). In contrast, torcetrapib reduced concentrations of apoA-II in alpha-3-migrating HDL, with mean reductions of -14% (P = 0.23), -18% (P < 0.02), and -18% (P < 0.01) noted during the atorvastatin and nonatorvastatin 120 mg once- and twice-daily phases, respectively. Our findings indicate that CETP inhibition increases plasma concentrations of apoA-II by delaying HDL apoA-II catabolism and significantly alters the remodeling of apoA-II-containing HDL subpopulations.

Health-risk appraisal with or without disease management for worksite cardiovascular risk reduction.

BACKGROUND AND RESEARCH OBJECTIVE: Worksite health promotion programs use health risk appraisal (HRA) surveys to identify employees at increased risk, then provide a range of interventions to encourage high-risk individuals to improve their health. Our objective was to determine how the intensity of intervention after HRA affected cardiovascular risk after 1 year, comparing individual follow-up counseling with environmental supports. SUBJECTS AND METHODS: 133 employees of Vanderbilt University with cardiovascular risk factors were randomly assigned to worksite HRA plus targeted disease management (DM group) or HRA plus information about worksite health promotion programs (HRA group). The DM group received longitudinal individualized counseling for risk reduction, whereas the HRA group members received one feedback session about their risk factors and information about free worksite health promotion programs. The main outcome measure was the difference between groups in the change in average Framingham risk score from baseline to 1 year. RESULTS: There was no significant baseline difference between groups in the Framingham risk score. Among DM participants, the mean (SD) Framingham risk score decreased by 22.6%; among HRA participants, the mean score rose by 4.3% (P = .017 for the difference between groups). CONCLUSIONS: In this study of employees with cardiovascular risk factors, HRA followed by individual counseling was more effective than providing information about free worksite health promotion programs.

Effects of the cholesteryl ester transfer protein inhibitor torcetrapib on VLDL apolipoprotein E metabolism.

Cholesteryl ester transfer protein (CETP) inhibition leads to changes in lipoprotein metabolism. We studied the effect of the CETP inhibitor torcetrapib on VLDL apolipoprotein E (apoE) metabolism. Subjects, pretreated with atorvastatin (n = 9) or untreated (n = 10), received placebo followed by torcetrapib (4 weeks each). After each treatment, subjects underwent a primed-constant infusion of D(3)-leucine to determine the VLDL apoE production rate (PR) and fractional catabolic rate (FCR). Torcetrapib alone reduced the VLDL apoE pool size (PS) (-28%) by increasing the VLDL apoE FCR (77%) and leaving the VLDL apoE PR unchanged. In subjects pretreated with atorvastatin, torcetrapib increased the VLDL apoE FCR (25%) and PR (21%). This left the VLDL apoE PS unchanged but increased the VLDL apoE content, likely enhancing VLDL clearance and reducing LDL production in this group. Used alone, torcetrapib reduces the VLDL apoE PS by increasing the apoE FCR while leaving the VLDL apoE content unchanged. In contrast, torcetrapib added to atorvastatin treatment increases both the VLDL apoE FCR and PR, leaving the VLDL apoE PS unchanged. Adding torcetrapib to atorvastatin treatment increases the VLDL apoE content, likely leading to decreased conversion of VLDL to LDL, reduced LDL production, and lower levels of circulating VLDL and LDL.

Effects of the cholesteryl ester transfer protein inhibitor torcetrapib on apolipoprotein B100 metabolism in humans.

OBJECTIVE: Cholesteryl ester transfer protein (CETP) inhibition with torcetrapib not only increases high-density lipoprotein cholesterol levels but also significantly reduces plasma triglyceride, low-density lipoprotein (LDL) cholesterol, and apolipoprotein B (apoB) levels. The goal of the present study was to define the kinetic mechanism(s) by which CETP inhibition reduces levels of apoB-containing lipoproteins. METHODS AND RESULTS: Nineteen subjects, 9 of whom were pretreated with 20 mg atorvastatin, received placebo for 4 weeks, followed by 120 mg torcetrapib once daily for 4 weeks. Six subjects in the nonatorvastatin group received 120 mg torcetrapib twice daily for an additional 4 weeks. After each phase, subjects underwent a primed-constant infusion of deuterated leucine to endogenously label newly synthesized apoB to determine very low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL) and LDL apoB100 production, and fractional catabolic rates (FCRs). Once-daily 120 mg torcetrapib significantly reduced VLDL, IDL, and LDL apoB100 pool sizes by enhancing the FCR of apoB100 within each fraction. On a background of atorvastatin, 120 mg torcetrapib significantly reduced VLDL, IDL, and LDL apoB100 pool sizes. The reduction in VLDL apoB100 was associated with an enhanced apoB100 FCR, whereas the decreases in IDL and LDL apoB100 were associated with reduced apoB100 production. CONCLUSIONS: These data indicate that when used alone, torcetrapib reduces VLDL, IDL, and LDL apoB100 levels primarily by increasing the rate of apoB100 clearance. In contrast, when added to atorvastatin treatment, torcetrapib reduces apoB100 levels mainly by enhancing VLDL apoB100 clearance and reducing production of IDL and LDL apoB100.

Effects of cholesteryl ester transfer protein inhibition on high-density lipoprotein subspecies, apolipoprotein A-I metabolism, and fecal sterol excretion.

OBJECTIVE: Pharmacological inhibition of the cholesteryl ester transfer protein (CETP) in humans increases high-density lipoprotein (HDL) cholesterol (HDL-C) levels; however, its effects on apolipoprotein A-I (apoA-I) containing HDL subspecies, apoA-I turnover, and markers of reverse cholesterol transport are unknown. The present study was designed to address these issues. METHODS AND RESULTS: Nineteen subjects, 9 of whom were taking 20 mg of atorvastatin for hypercholesterolemia, received placebo for 4 weeks, followed by the CETP inhibitor torcetrapib (120 mg QD) for 4 weeks. In 6 subjects from the nonatorvastatin cohort, the everyday regimen was followed by a 4-week period of torcetrapib (120 mg BID). At the end of each phase, subjects underwent a primed-constant infusion of (5,5,5-2H3)-L-leucine to determine the kinetics of HDL apoA-I. The lipid data in this study have been reported previously. Relative to placebo, 120 mg daily torcetrapib increased the amount of apoA-I in alpha1-migrating HDL in the atorvastatin (136%; P<0.001) and nonatorvastatin (153%; P<0.01) cohorts, whereas an increase of 382% (P<0.01) was observed in the 120 mg twice daily group. HDL apoA-I pool size increased by 8+/-15% in the atorvastatin cohort (P=0.16) and by 16+/-7% (P<0.0001) and 34+/-8% (P<0.0001) in the nonatorvastatin 120 mg QD and BID cohorts, respectively. These changes were attributable to reductions in HDL apoA-I fractional catabolic rate (FCR), with torcetrapib reducing HDL apoA-I FCR by 7% (P=0.10) in the atorvastatin cohort, by 8% (P<0.001) in the nonatorvastatin 120 mg QD cohort, and by 21% (P<0.01) in the nonatorvastatin 120 mg BID cohort. Torcetrapib did not affect HDL apoA-I production rate. In addition, torcetrapib did not significantly change serum markers of cholesterol or bile acid synthesis or fecal sterol excretion. CONCLUSIONS: These data indicate that partial inhibition of CETP via torcetrapib in patients with low HDL-C: (1) normalizes apoA-I levels within alpha1-migrating HDL, (2) increases plasma concentrations of HDL apoA-I by delaying apoA-I catabolism, and (3) does not significantly influence fecal sterol excretion.

Evaluation of methods for improving precision of blood pressure measurements in phase I clinical trials.

Small sample sizes are typically incorporated in early Phase I clinical studies, which may lead to insignificant changes in safety parameters such as blood pressure. Therefore, it is paramount to identify an optimal, noninvasive method of accurately measuring blood pressure and an appropriate analysis strategy yielding the smallest variability. The goals of this study were (1) to compare the variability between automated and manual blood pressure measurements, (2) to determine whether triplicate blood pressure measurements were independent of one another, and (3) to assess how the number of blood pressure readings affects variability and study sample size. Twenty healthy volunteers were enrolled in this randomized, two-way crossover study. Each subject received three incremental infusions of phenylephrine or normal saline on separate days to simulate blood pressure variability. The mean systolic blood pressure readings with the automated device were consistently higher than the manual device by 3 to 5 mmHg. Conversely, the mean diastolic blood pressure readings with the automated device were consistently 3 to 5 mmHg lower than the manual device. However, the variability and absolute change in blood pressure were essentially identical with manual and automated methods. No systematic order effects such as the first blood pressure reading always being higher were detected, suggesting that the triplicate readings were independent of one another and that an interval of 2 minutes between readings is adequate. Compared to a single measurement, collecting blood pressure in triplicate results in a 40% lower sample size needed to detect a 5-mmHg difference in systolic blood pressure.

Effects of an inhibitor of cholesteryl ester transfer protein on HDL cholesterol.

BACKGROUND: Decreased high-density lipoprotein (HDL) cholesterol levels constitute a major risk factor for coronary heart disease; however, there are no therapies that substantially raise HDL cholesterol levels. Inhibition of cholesteryl ester transfer protein (CETP) has been proposed as a strategy to raise HDL cholesterol levels. METHODS: We conducted a single-blind, placebo-controlled study to examine the effects of torcetrapib, a potent inhibitor of CETP, on plasma lipoprotein levels in 19 subjects with low levels of HDL cholesterol (<40 mg per deciliter [1.0 mmol per liter]), 9 of whom were also treated with 20 mg of atorvastatin daily. All the subjects received placebo for four weeks and then received 120 mg of torcetrapib daily for the following four weeks. Six of the subjects who did not receive atorvastatin also participated in a third phase, in which they received 120 mg of torcetrapib twice daily for four weeks. RESULTS: Treatment with 120 mg of torcetrapib daily increased plasma concentrations of HDL cholesterol by 61 percent (P<0.001) and 46 percent (P=0.001) in the atorvastatin and non-atorvastatin cohorts, respectively, and treatment with 120 mg twice daily increased HDL cholesterol by 106 percent (P<0.001). Torcetrapib also reduced low-density lipoprotein (LDL) cholesterol levels by 17 percent in the atorvastatin cohort (P=0.02). Finally, torcetrapib significantly altered the distribution of cholesterol among HDL and LDL subclasses, resulting in increases in the mean particle size of HDL and LDL in each cohort. CONCLUSIONS: In subjects with low HDL cholesterol levels, CETP inhibition with torcetrapib markedly increased HDL cholesterol levels and also decreased LDL cholesterol levels, both when administered as monotherapy and when administered in combination with a statin.