Effect of a Garlic Oil Preparation on Serum Lipoproteins and Cholesterol Metabolism: A Randomized Controlled Trial

Context.— Garlic-containing drugs have been used in the treatment of hypercholesterolemia even though their efficacy is not generally established. Little is known about the mechanisms of action of the possible effects on cholesterol in humans. Objective.— To estimate the hypocholesterolemic effect of garlic oil and to investigate the possible mechanism of action. Design.— Double-blind, randomized, placebo-controlled trial. Setting.— Outpatient lipid clinic. Patients.— We investigated 25 patients (mean age, 58 years) with moderate hypercholesterolemia. Intervention.— Steam-distilled garlic oil preparation (5 mg twice a day) vs placebo each for 12 weeks with wash-out periods of 4 weeks. Main Outcome Measures.— Serum lipoprotein concentrations, cholesterol absorption, and cholesterol synthesis. Results.— Baseline lipoprotein profiles were (mean [SD]): total cholesterol, 7.53 (0.75) mmol/L (291 [29] mg/dL); low-density lipoprotein cholesterol (LDL-C), 5.35 (0.78) mmol/L (207 [30] mg/dL); high-density lipoprotein cholesterol (HDL-C), 1.50 (0.41) mmol/L (58 [16] mg/dL); and triglycerides, 1.45 (0.73) mmol/L (127 [64] mg/dL). Lipoprotein levels were virtually unchanged at the end of both treatment periods (mean difference [95% confidence interval]): total cholesterol, 0.085 (-0.201 to 0.372) mmol/L (3.3 [-7.8 to 14.4] mg/dL), P=.54; LDL-C, 0.001 (-0.242 to 0.245) mmol/L (0.04 [-9.4 to 9.5] mg/dL), P=.99; HDL-C, 0.050 (-0.028 to 0.128) mmol/L (1.9 [-1.1 to 4.9] mg/dL), P=.20; triclycerides, 0.047 (-0.229 to 0.135) mmol/L (4.2 [-20.3 to 12.0]) mg/dL, P=.60. Cholesterol absorption (37.5% [10.5%] vs 38.3% [10.7%], P=.58), cholesterol synthesis (12.7 [6.5] vs 13.4 [6.6] mg/kg of body weight per day, P=.64), mevalonic acid excretion (192 [66] vs 187 [66] µg/d, P=.78), and changes in the ratio of lathosterol to cholesterol in serum (4.4% [24.3%] vs 10.6% [21.1%], P=.62) were not different in garlic and placebo treatment. Conclusions.— The commercial garlic oil preparation investigated had no influence on serum lipoproteins, cholesterol absorption, or cholesterol synthesis. Garlic therapy for treatment of hypercholesterolemia cannot be recommended on the basis of this study.      

Statins, high-density lipoprotein cholesterol, and regression of coronary atherosclerosis

Context  Statins reduce low-density lipoprotein cholesterol (LDL-C) levels and slow progression of coronary atherosclerosis. However, no data exist describing the relationship between statin-induced changes in high-density lipoprotein cholesterol (HDL-C) and disease progression. Objective  To investigate the relationship between changes in LDL-C and HDL-C levels and atheroma burden. Design, Setting, and Patients  Post-hoc analysis combining raw data from 4 prospective randomized trials (performed in the United States, North America, Europe, and Australia between 1999 and 2005), in which 1455 patients with angiographic coronary disease underwent serial intravascular ultrasonography while receiving statin treatment for 18 months or for 24 months. Ultrasound analysis was performed in the same core laboratory for all of the studies. Main Outcome Measure  Relationship between changes in lipoprotein levels and coronary artery atheroma volume. Results  During statin therapy, mean (SD) LDL-C levels were reduced from 124.0 (38.3) mg/dL (3.2 [0.99] mmol/L) to 87.5 (28.8) mg/dL (2.3 [0.75] mmol/L) (a 23.5% decrease; P<.001), and HDL-C levels increased from 42.5 (11.0) mg/dL (1.1 [0.28] mmol/L) to 45.1 (11.4) mg/dL (1.2 [0.29] mmol/L) (a 7.5% increase; P<.001). The ratio of LDL-C to HDL-C was reduced from a mean (SD) of 3.0 (1.1) to 2.1 (0.9) (a 26.7% decrease; P<.001). These changes were accompanied by a mean (SD) increase in percent atheroma volume from 39.7% (9.8%) to 40.1% (9.7%) (a 0.5% [3.9%] increase; P = .001) and a mean (SD) decrease in total atheroma volume of 2.4 (23.6) mm³ (P<.001). In univariate analysis, mean levels and treatment-mediated changes in LDL-C, total cholesterol, non-HDL cholesterol, apolipoprotein B, and ratio of apolipoprotein B to apolipoprotein A-I were significantly correlated with the rate of atherosclerotic progression, whereas treatment-mediated changes in HDL-C were inversely correlated with atheroma progression. In multivariate analysis, mean levels of LDL-C ( coefficient, 0.11 [95% confidence interval, 0.07-0.15]) and increases in HDL-C ( coefficient, –0.26 [95% confidence interval, –0.41 to –0.10]) remained independent predictors of atheroma regression. Substantial atheroma regression (5% reduction in atheroma volume) was observed in patients with levels of LDL-C less than the mean (87.5 mg/dL) during treatment and percentage increases of HDL-C greater than the mean (7.5%; P<.001). No significant differences were found with regard to clinical events. Conclusions  Statin therapy is associated with regression of coronary atherosclerosis when LDL-C is substantially reduced and HDL-C is increased by more than 7.5%. These findings suggest that statin benefits are derived from both reductions in atherogenic lipoprotein levels and increases in HDL-C, although it remains to be determined whether the atherosclerotic regression associated with these changes in lipid levels will translate to meaningful reductions in clinical events and improved clinical outcomes.      

Impact of HIV infection and HAART on serum lipids in men

Context  Alterations in serum lipid values have been widely reported among persons infected with human immunodeficiency virus (HIV) type 1 treated with highly active antiretroviral therapy (HAART), but no data have yet been reported on changes from preseroconversion lipid values. Objective  To describe changes in serum cholesterol levels associated with HIV infection and antiretroviral medication exposure, and 1-time assessment of triglyceride levels post-HAART initiation. Design, Setting, and Participants  The Multicenter AIDS Cohort Study, a prospective study in which homosexual and bisexual men were enrolled and from which 50 of 517 HIV seroconverters were drawn for the analysis herein, who later initiated HAART, involving measurements of stored serum samples obtained between 1984 and 2002. Main Outcome Measures  Changes in levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) at 6 time points during an average of 12 years; 1-time assessment of triglyceride levels from the third post-HAART clinic visit. Results  Among the 50 men, notable declines in mean serum TC (–30 mg/dL [-0.78 mmol/L]), HDL-C (–12 mg/dL [-0.31 mmol/L]), and LDL-C values (–22 mg/dL [-0.57 mmol/L]) were observed after HIV infection. Following HAART initiation, there were large increases in mean TC and LDL-C values (50 and 21 mg/dL [1.30 and 0.54 mmol/L], respectively); however, the mean changes from the preseroconversion values were 20 mg/dL (0.52 mmol/L) (95% confidence interval [CI], –1 to 41) and –1 mg/dL (-0.03 mmol/L) (95% CI, –25 to 22), respectively. Mean HDL-C remained below baseline levels throughout follow-up. The median value (interquartile range) of triglycerides was 225 mg/dL (2.54 mmol/L) (147-331 mg/dL). Conclusions  Before treatment, HIV infection results in substantial decreases in serum TC, HDL-C, and LDL-C levels. Subsequent HAART initiation is associated with increases in TC and LDL-C but little change in HDL-C. Increases in TC and LDL-C observed after about 3 years of HAART possibly represent a return to preinfection serum lipid levels after accounting for expected age-related changes.      

Health Economic Benefits and Quality of Life During Improved Glycemic Control in Patients With Type 2 Diabetes Mellitus: A Randomized, Controlled, Double-Blind Trial

Context.— Although the long-term health benefits of good glycemic control in patients with diabetes are well documented, shorter-term quality of life (QOL) and economic savings generally have been reported to be minimal or absent. Objective.— To examine short-term outcomes of glycemic control in type 2 diabetes mellitus (DM). Design.— Double-blind, randomized, placebo-controlled, parallel trial. Setting.— Sixty-two sites in the United States. Participants.— A total of 569 male and female volunteers with type 2 DM. Intervention.— After a 3-week, single-blind placebo-washout period, participants were randomized to diet and titration with either 5 to 20 mg of glipizide gastrointestinal therapeutic system (GITS) (n=377) or placebo (n=192) for 12 weeks. Main Outcome Measures.— Change from baseline in glucose and hemoglobin A_1c (HbA_1c) levels and symptom distress, QOL, and health economic indicators by questionnaires and diaries. Results.— After 12 weeks, mean (±SE) HbA_1c and fasting blood glucose levels decreased with active therapy (glipizide GITS) vs placebo (7.5%±0.1% vs 9.3%±0.1% and 7.0±0.1 mmol/L [126±2 mg/dL] vs 9.3±0.2 mmol/L [168±4 mg/dL], respectively; P<.001). Quality-of-life treatment differences (SD units) for symptom distress (+0.59; P<.001), general perceived health (+0.36; P=.004), cognitive functioning (+0.34; P=.005), and the overall visual analog scale (VAS) (+0.24; P=.04) were significantly more favorable for active therapy. Subscales of acuity (+0.38; P=.002), VAS emotional health (+0.35; P =.003), general health (+0.27; P =.01), sleep (+0.26; P =.04), depression (+0.25; P =.05), disorientation and detachment (+0.23; P =.05), and vitality (+0.22; P =.04) were most affected. Favorable health economic outcomes for glipizide GITS included higher retained employment (97% vs 85%; P<.001), greater productive capacity (99% vs 87%; P<.001), less absenteeism (losses=$24 vs $115 per worker per month; P <.001), fewer bed-days (losses=$1539 vs $1843 per 1000 person-days; P=.05), and fewer restricted-activity days (losses=$2660 vs $4275 per 1000 person-days; P=.01). Conclusions.— Improved glycemic control of type 2 DM is associated with substantial short-term symptomatic, QOL, and health economic benefits.      

A Prospective Trial of Risk Factors for Sulfonylurea-Induced Hypoglycemia in Type 2 Diabetes Mellitus

Context.— Retrospective studies have identified oral sulfonylureas, age, and fasting as major risk factors for hypoglycemia in patients with type 2 diabetes. Sulfonylureas may be withheld from elderly patients out of concern for hypoglycemia. Objective.— To evaluate the hypoglycemic effects of maximum doses of once-daily second-generation sulfonylureas administered to fasting elderly patients. Design.— A prospective, randomized, double-blind clinical trial. Setting.— The University of New Mexico General Clinical Research Center. Patients.— Fifty-two sulfonylurea-treated subjects with type 2 diabetes with a mean (SD) age of 65.1 (5.7) years. Interventions.— Subjects were randomly assigned to glyburide or glipizide gastrointestinal therapeutic system (GITS). Each subject participated in three 23-hour fasting studies after the sequential administration of 1 week of placebo and 1 week of 10 mg and 1 week of 20 mg of the assigned sulfonylurea. Main Outcome Measures.— Occurrence of hypoglycemia (defined as plasma glucose level <3.33 mmol/L [60 mg/dL]) and hormonal parameters during the final 9 hours of the 23-hour fast in patients who had taken sulfonylureas vs placebo. Results.— No hypoglycemia was observed during 156 fasting studies. Plasma glucose level was decreased (nadir, 4.9 mmol/L [88 mg/dL] for a 20-mg dose of glyburide vs 8.3 mmol/L [150 mg/dL] for placebo; nadir, 5.8 mmol/L [105 mg/dL] for a 20-mg dose of glipizide GITS vs 8.7 mmol/L [157 mg/dL] for placebo), and serum insulin was increased in the sulfonylurea studies compared with placebo (P<.001). Plasma glucose parameters did not differ between the 2 sulfonylureas, but C peptide concentrations were increased in the glyburide group compared with glipizide GITS in the 20-mg study (P=.05). Concentrations of epinephrine were increased in the sulfonylurea studies compared with placebo (P<.001). Epinephrine secretion increased when glucose concentration fell below the mean (SD) level of 9.10 (2.66) mmol/L (164 [48] mg/dL) in the 10-mg study and 8.77 (2.83) mmol/L (158 [51] mg/dL) in the 20-mg study. Conclusions.— Fasting was well tolerated among these elderly patients with type 2 diabetes treated with sulfonylureas. Older age should not be considered a contraindication to sulfonylurea treatment for diabetes. Stimulation of epinephrine secretion at normal or elevated plasma glucose levels appears to be the primary mechanism of protection against hypoglycemia in this study.      

Effect of Excessive Weight Gain With Intensive Therapy of Type 1 Diabetes on Lipid Levels and Blood Pressure: Results From the DCCT

Context.— Intensive treatment of type 1 diabetes results in greater weight gain than conventional treatment. Objective.— To determine the effect of this weight gain on lipid levels and blood pressure. Design.— Randomized controlled trial; ancillary study of the Diabetes Control and Complications Trial (DCCT). Setting.— Twenty-one clinical centers. Participants.— The 1168 subjects enrolled in DCCT with type 1 diabetes who were aged 18 years or older at baseline. Intervention.— Randomized to receive either intensive (n=586) or conventional (n=582) diabetes treatment with a mean follow-up of 6.1 years. Main Outcome Measures.— Plasma lipid levels and blood pressure in each treatment group categorized by quartile of weight gain. Results.  —With intensive treatment, subjects in the fourth quartile of weight gain had the highest body mass index (BMI) (a measure of weight adjusted for height), blood pressure, and levels of triglyceride, total cholesterol, low-density lipoprotein cholesterol (LDL-C), and apolipoprotein B compared with the other weight gain quartiles with the greatest difference seen when compared with the first quartile (mean values for the highest and lowest quartiles: BMI, 31 vs 24 kg/m²; blood pressure, 120/77 mm Hg vs 113/73 mm Hg; triglyceride, 0.99 mmol/L vs 0.79 mmol/L [88 mg/dL vs 70 mg/dL]; LDL-C, 3.15 mmol/L vs 2.74 mmol/L [122 mg/dL vs 106 mg/dL]; and apolipoprotein B, 0.89 g/L vs 0.78 g/L; all P<.001). In addition, the fourth quartile group had a higher waist-to-hip ratio; more cholesterol in the very low density lipoprotein, intermediate dense lipoprotein, and dense LDL fractions; and lower high-density lipoprotein cholesterol and apolipoprotein A-I levels compared with the first quartile. Baseline characteristics were not different between the first and fourth quartiles of weight gain with intensive therapy except for a higher hemoglobin A_1c in the fourth quartile. Weight gain with conventional therapy resulted in smaller increases in BMI, lipids, and systolic blood pressure. Conclusions.— The changes in lipid levels and blood pressure that occur with excessive weight gain with intensive therapy are similar to those seen in the insulin resistance syndrome and may increase the risk of coronary artery disease in this subset of subjects with time.      

Influence of a Child's Sex on Medulloblastoma Outcome

Context.— Aggressive treatment of medulloblastoma, the most common pediatric brain tumor, has not improved survival. Identifying better prognostic indicators may warrant less morbid therapy. Objective.— To investigate the role of sex on outcome of medulloblastoma. Design.— Retrospective study of significant factors for survival with a median follow-up of 82 months. Setting.— University medical center. Patients.— A total of 109 consecutive, pediatric patients treated for primary medulloblastoma from 1970 to 1995 with surgery and postoperative radiotherapy and, after 1979, chemotherapy. Main Outcome Measures.— Factors independently associated with survival. Results.— The final multivariate model predicting improved survival included sex (hazard ratio, 0.52; 95% confidence interval [CI], 0.29-0.92; P=.03; favoring female), metastases at presentation (hazard ratio, 2.01; 95% CI, 1.14-3.52; P=.02), and extent of surgical resection (hazard ratio, 0.60; 95% CI, 0.34-1.04; P=.07; favoring greater resection). The overall, 5-year freedom from progression was 40% and survival was 49%. Radiotherapy dose (P=.72), and chemotherapy (P=.90) did not significantly affect a disease outcome. Conclusions.— The sex of the child was an important predictor for survival of medulloblastoma; girls had a much better outcome. The difference in survival between sexes should be evaluated in prospective, clinical trials.      

Fluvastatin for prevention of cardiac events following successful first percutaneous coronary intervention: a randomized controlled trial

Context  Percutaneous coronary intervention (PCI) is associated with excellent short-term improvements in ischemic symptoms, yet only three fifths of PCI patients at 5 years and one third of patients at 10 years remain free of major adverse cardiac events (MACE). Objective  To determine whether treatment with fluvastatin reduces MACE in patients who have undergone PCI. Design and Setting  Randomized, double-blind, placebo-controlled trial conducted at 77 referral centers in Europe, Canada, and Brazil. Patients  A total of 1677 patients (aged 18-80 years) recruited between April 1996 and October 1998 with stable or unstable angina or silent ischemia following successful completion of their first PCI who had baseline total cholesterol levels between 135 and 270 mg/dL (3.5-7.0 mmol/L), with fasting triglyceride levels of less than 400 mg/dL (4.5 mmol/L). Interventions  Patients were randomly assigned to receive treatment with fluvastatin, 80 mg/d (n = 844), or matching placebo (n = 833) at hospital discharge for 3 to 4 years. Main Outcome Measure  Survival time free of MACE, defined as cardiac death, nonfatal myocardial infarction, or reintervention procedure, compared between the treatment and placebo groups. Results  Median time between PCI and first dose of study medication was 2.0 days, and median follow-up was 3.9 years. MACE-free survival time was significantly longer in the fluvastatin group (P = .01). One hundred eighty-one (21.4%) of 844 patients in the fluvastatin group and 222 (26.7%) of 833 patients in the placebo group had at least 1 MACE (relative risk [RR], 0.78; 95% confidence interval [CI], 0.64-0.95; P = .01). This result was independent of baseline total cholesterol levels (above [RR, 0.76; 95% CI, 0.56-1.04] vs below [RR, 0.77; 95% CI, 0.57-1.02] the median). In subgroup analysis, the risk of MACE was reduced in patients with diabetes (n = 202; RR, 0.53; 95% CI, 0.29-0.97; P = .04) and in those with multivessel disease (n = 614; RR, 0.66; 95% CI, 0.48-0.91; P = .01) who received fluvastatin compared with those who received placebo. There were no instances of creatine phosphokinase elevations 10 or more times the upper limit of normal or rhabdomyolysis in the fluvastatin group. Conclusion  Fluvastatin treatment in patients with average cholesterol levels undergoing their first successful PCI significantly reduces the risk of major adverse cardiac events.      

Effect of very high-intensity statin therapy on regression of coronary atherosclerosis: the ASTEROID trial

Context  Prior intravascular ultrasound (IVUS) trials have demonstrated slowing or halting of atherosclerosis progression with statin therapy but have not shown convincing evidence of regression using percent atheroma volume (PAV), the most rigorous IVUS measure of disease progression and regression. Objective  To assess whether very intensive statin therapy could regress coronary atherosclerosis as determined by IVUS imaging. Design and Setting  Prospective, open-label blinded end-points trial (A Study to Evaluate the Effect of Rosuvastatin on Intravascular Ultrasound-Derived Coronary Atheroma Burden [ASTEROID]) was performed at 53 community and tertiary care centers in the United States, Canada, Europe, and Australia. A motorized IVUS pullback was used to assess coronary atheroma burden at baseline and after 24 months of treatment. Each pair of baseline and follow-up IVUS assessments was analyzed in a blinded fashion. Patients  Between November 2002 and October 2003, 507 patients had a baseline IVUS examination and received at least 1 dose of study drug. After 24 months, 349 patients had evaluable serial IVUS examinations. Intervention  All patients received intensive statin therapy with rosuvastatin, 40 mg/d. Main Outcome Measures  Two primary efficacy parameters were prespecified: the change in PAV and the change in nominal atheroma volume in the 10-mm subsegment with the greatest disease severity at baseline. A secondary efficacy variable, change in normalized total atheroma volume for the entire artery, was also prespecified. Results  The mean (SD) baseline low-density lipoprotein cholesterol (LDL-C) level of 130.4 (34.3) mg/dL declined to 60.8 (20.0) mg/dL, a mean reduction of 53.2% (P<.001). Mean (SD) high-density lipoprotein cholesterol (HDL-C) level at baseline was 43.1 (11.1) mg/dL, increasing to 49.0 (12.6) mg/dL, an increase of 14.7% (P<.001). The mean (SD) change in PAV for the entire vessel was –0.98% (3.15%), with a median of –0.79% (97.5% CI, –1.21% to –0.53%) (P<.001 vs baseline). The mean (SD) change in atheroma volume in the most diseased 10-mm subsegment was –6.1 (10.1) mm³, with a median of –5.6 mm³ (97.5% CI, –6.8 to –4.0 mm³) (P<.001 vs baseline). Change in total atheroma volume showed a 6.8% median reduction; with a mean (SD) reduction of –14.7 (25.7) mm³, with a median of –12.5 mm³ (95% CI, –15.1 to –10.5 mm³) (P<.001 vs baseline). Adverse events were infrequent and similar to other statin trials. Conclusions  Very high-intensity statin therapy using rosuvastatin 40 mg/d achieved an average LDL-C of 60.8 mg/dL and increased HDL-C by 14.7%, resulting in significant regression of atherosclerosis for all 3 prespecified IVUS measures of disease burden. Treatment to LDL-C levels below currently accepted guidelines, when accompanied by significant HDL-C increases, can regress atherosclerosis in coronary disease patients. Further studies are needed to determine the effect of the observed changes on clinical outcome. Trial Registration  ClinicalTrials.gov Identifier: NCT00240318      

Comparison of pioglitazone vs glimepiride on progression of coronary atherosclerosis in patients with type 2 diabetes: the PERISCOPE randomized controlled trial

Context  No antidiabetic regimen has demonstrated the ability to reduce progression of coronary atherosclerosis. Commonly used oral glucose-lowering agents include sulfonylureas, which are insulin secretagogues, and thiazolidinediones, which are insulin sensitizers. Objective  To compare the effects of an insulin sensitizer, pioglitazone, with an insulin secretagogue, glimepiride, on the progression of coronary atherosclerosis in patients with type 2 diabetes. Design, Setting, and Participants  Double-blind, randomized, multicenter trial at 97 academic and community hospitals in North and South America (enrollment August 2003-March 2006) in 543 patients with coronary disease and type 2 diabetes. Interventions  A total of 543 patients underwent coronary intravascular ultrasonography and were randomized to receive glimepiride, 1 to 4 mg, or pioglitazone, 15 to 45 mg, for 18 months with titration to maximum dosage, if tolerated. Atherosclerosis progression was measured by repeat intravascular ultrasonography examination in 360 patients at study completion. Main Outcome Measure  Change in percent atheroma volume (PAV) from baseline to study completion. Results  Least squares mean PAV increased 0.73% (95% CI, 0.33% to 1.12%) with glimepiride and decreased 0.16% (95% CI, –0.57% to 0.25%) with pioglitazone(P = .002). An alternative analysis imputing values for noncompleters based on baseline characteristics showed an increase in PAV of 0.64% (95% CI, 0.23% to 1.05%) for glimepiride and a decrease of 0.06% (–0.47% to 0.35%) for pioglitazone (between-group P = .02). Mean (SD) baseline HbA_1c levels were 7.4% (1.0%) in both groups and declined during treatment an average 0.55% (95% CI, –0.68% to –0.42%) with pioglitazone and 0.36% (95% CI, –0.48% to –0.24%) with glimepiride (between-group P = .03). In the pioglitazone group, compared with glimepiride, high-density lipoprotein levels increased 5.7 mg/dL (95% CI, 4.4 to 7.0 mg/dL; 16.0%) vs 0.9 mg/dL (95% CI, –0.3 to 2.1 mg/dL; 4.1%), and median triglyceride levels decreased 16.3 mg/dL (95% CI, –27.7 to –11.0 mg/dL; 15.3%) vs an increase of 3.3 mg/dL (95% CI, –10.7 to 11.7 mg/dL; 0.6%) (P < .001 for both comparisons). Median fasting insulin levels decreased with pioglitazone and increased with glimepiride (P < .001). Hypoglycemia was more common in the glimepiride group and edema, fractures, and decreased hemoglobin levels occurred more frequently in the pioglitazone group. Conclusion  In patients with type 2 diabetes and coronary artery disease, treatment with pioglitazone resulted in a significantly lower rate of progression of coronary atherosclerosis compared with glimepiride. Trial Registration  clinicaltrials.gov Identifier: NCT00225277