Changes In Blood Lipid Profile Research Articles

Pharmacoepidemiology of anabolic androgenic steroids: a review

Non-prescribed use of anabolic androgenic steroids (AAS) has been associated with a number of physical and psychiatric/behavioural complications, some of which are potentially lethal. Here, we review both observational and experimental studies on human subjects concerned with such side-effects. The only physical complication of AAS use that receives definitive support from such investigations is unfavourable changes in blood lipid profiles. Support for various psychiatric complications has also been provided by a number of cross-sectional studies, most involving comparisons between weight-training individuals who use or do not use AAS. Certain of these complications, in particular hypomania and increased aggressiveness, have been confirmed in some, but not all, randomized controlled studies. Epidemiological attempts to determine whether AAS use triggers violent behaviour have failed, primarily because of high rates of non-participation. Studies regarding the prevalence of AAS use in different populations typically report life-time prevalences of 1-5% among adolescents. However, the life-time prevalence (i.e. use on at least one occasion) is of doubtful relevance in attempting to estimate the number of individuals at risk for side-effects, as most of these complications appear to develop during prolonged use of AAS. Furthermore, it is reasonable to assume that the symptoms and signs of AAS use are often overlooked by healthcare professionals, so that the number of cases of possible AAS-related complications is virtually unknown. These limitations, together with an apparently low prevalence of prolonged AAS use among the general population, indicate that future epidemiological research in this area should focus on retrospective case-control studies and, perhaps, also on prospective cohort studies of populations selected for a high prevalence of AAS use, rather than attempting to perform large-scale population-based studies.

Contribution of abdominal adiposity to age-related differences in insulin sensitivity and plasma lipids in healthy nonobese women.

We examined the hypothesis that an age-related increase in the compartments of visceral fat would account, in part, for the deleterious changes in insulin sensitivity and blood lipid profile in nonobese women. We directly assessed visceral and subcutaneous abdominal adipose tissue areas (computed tomography), glucose disposal (hyperinsulinemic-euglycemic clamp), body composition (dual energy X-ray absorptiometry), blood-lipid profile, and aerobic fitness (VO2max) in 178 nonobese women categorized into four age groups: group 1, 28 +/- 4 years, n = 88; group 2, 46 +/- 2 years, n = 38; group 3, 53 +/- 2 years, n = 31; and group 4. 67 +/- 6 years, n = 21. Visceral abdominal adipose tissue area increased with age (2.36 cm2 per year, P < 0.0001). We noted an age-related increase in total cholesterol (P < 0.0003), triglycerides (P < 0.0009), LDL cholesterol (P < 0.027), and the ratio of total cholesterol to HDL cholesterol (P < 0.042). However, age-related changes in insulin sensitivity exhibited a different age-related pattern. That is, insulin sensitivity, expressed on an absolute basis or indexed per kilogram of fat-free mass, was lowest in group 4 but was not significantly different among groups 1, 2, and 3. After statistical control for visceral fat, lower insulin sensitivity persisted in group 4, although differences were diminished relative to other groups. However, the effect of visceral fat on age-related changes in the blood-lipid profile was stronger. That is, differences in visceral and deep subcutaneous adipose tissue area abolished age-related differences in total cholesterol, triglycerides, and LDL cholesterol. No independent effects of VO2max or leisure-time physical activity on age-related changes in insulin sensitivity or on the blood-lipid profile were noted. We conclude that 1) visceral fat shows an increase with advancing age, whereas a decrease in insulin sensitivity was noted only in older women; 2) age-related differences in visceral fat explain only a modest part of the decline in insulin sensitivity in nonobese women; and 3) unfavorable changes in plasma lipids were strongly associated with the age-related increase in visceral abdominal adipose tissue.

Omega-3, -6, and -9 Fatty Acid Supplements Exert Different Effects on Serum Lipid Concentrations in Renal Dialysis Patients

■ Objective: To compare changes in blood lipid profiles of renal dialysis patients who consumed diets rich in either omega-3, -6, or -9 fatty acids over a 6-week period. ■ Design: Randomized before-after trial. ■ Setting: Three dialysis centers in the Dallas, TX, area. ■ Patients: Thirty-five maintenance hemodialysis patients were selected. Twenty-eight (9 men and 19 women) completed the study. Subjects were identified for inclusion for the study by the following criteria: concentrations of triglycerides (> 150 mg/dL) and cholesterol (> 180 mg/dL), absence of insulin-dependent diabetes, and absence of liver disease defined as three times greater than normal levels of serum glutamic pyruvic transaminase and serum glutamic oxaloacetic transaminase. ■ Interventions: Patients were given a daily supplement of either omega-3 fatty acid (3 g) MaxEPA (Seven Seas Health Care, Hull, England), omega-6 fatty acid (3 g) cottonseed oil, or omega-9 fatty acid (10% of caloric intake) pecan oil. ■ Main outcome measures: Fasting blood samples were obtained on days 0, 21, and 42 to determine serum total cholesterol (TChol), high-density lipoprotein cholesterol (HDL-C), HDL subfractions (HDL 2 -C and HDL 3 -C), and triglycerides (TG). ■ Results: A significant decrease in serum TChol was observed in the omega-9 fatty acid group. Significant decreases were also observed in the serum TG concentrations of the omega-3 and omega-9 fatty acid groups. Significant decreases in HDL-C were observed in the omega-3 fatty acid and control groups, whereas significant decreases in the HDL -C occurred in the control group. The HDL-C reduction in the omega-3 fatty acid group occurred primarily in the HDL -C subfraction. ■ Conclusions: Omega-3, -6, and -9 fatty acid supplements exert different effects on the serum lipid profiles of renal dialysis patients. New studies need to be initiated to determine the mechanisms responsible for this altered lipid metabolism and the clinical significance of these changes.

The effects of two fixed hormonal replacement therapy protocols on blood lipid profile

Hormonal Replacement Therapy (HRT) is known to be accompanied by changes in blood lipid profile. The present prospective cohort study compared the blood lipid profile of healthy post-menopausal women treated with either (a) a preparation containing a fixed regimen of estradiol, estriol and norethisterone acetate (EENA, marketed under the trade name Trisequens); (b) a fixed protocol of conjugated equine estrogen and medroxyprogesterone acetate (CEEMPA, marketed under the trade name Premaril Plus); or with (c) a concurrent group which underwent no treatment. Blood lipid profiles (total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), and triglycerides (TG)) were performed at the beginning of the study and at 3-month intervals, for 9 months. The EENA-treated women showed a significant and profound decrease in TC and LDL-C when compared with their initial values, with the control group, and with the CEEMPA group. The CEEMPA group showed an increase in HDL-C values and a decrease in LDL-C values when compared with their initial values and with the control group, but no increase was shown when compared with an EENA group. There was a favorable decrease in the TC HDL-C and LDL-C HDL-C ratios in both treatment protocols. As the primary goal of prevention of coronary artery disease is total cholesterol reduction, the EENA protocol seems to be preferred.

Immediate and delayed effects of marathon running on lipids and lipoproteins in women

The purpose of this investigation was to examine the immediate and delayed effects of prolonged strenuous exercise on plasma lipid and lipoprotein concentrations in female runners. Venous blood samples were collected from 12 female runners 24 h before, 10 min after, and 1, 3, and 5 d after running a 42 km marathon. Whole blood was analyzed for hematocrit and hemoglobin to determine plasma volume shifts. Plasma aliquots were assayed for total cholesterol, high-density lipoprotein cholesterol (HDL-C), and triglyceride concentrations, while low-density lipoprotein cholesterol (LDL-C) was estimated. Total cholesterol concentrations were significantly reduced 1 d following the exercise and were still lower 3 and 5 d post-marathon. LDL-C was lower immediately and 1 d after the marathon. HDL-C concentrations, corrected for changes in plasma volume, were elevated 24 h post-exercise. The ratio of HDL/total cholesterol was increased 24 h post-exercise. Triglyceride concentrations were elevated immediately following the marathon but returned to baseline levels by 24 h post-exercise. These results demonstrate that prolonged strenuous exercise in women produces changes in blood lipid profiles that can last for several days.

Hyperlipidemia in guinea pigs induced by chronic vitamin C deficiency

Sixteen weeks of chronic vitamin C deficiency, induced in guinea pigs by restricted vitamin C intake, resulted in a marked increase in the serum total LDL- and VLDL- cholesterol, triglycerides and total lipids. HDL-cholesterol decreased resulting in a highly significant increase in LDL/HDL ratio. The results reconfirm that vitamin C deficiency causes changes in blood lipid profile which could promote atherogenesis.