Biomedical subjects

Owe Johnson

Publications and source records attributed to Owe Johnson.

4 recordsLinked to original sources

PubMed2004

In face of the increasing efficacy of lipid-lowering therapy, is there still a place for LDL-apheresis?

Based on a large body of evidence, high LDL-cholesterol concentrations in blood is a key factor of coronary heart disease (CHD). Overall, the observational studies show a curvilinear relationship between blood cholesterol level and coronary heart disease risk. Even more relevant are the randomised trials, firmly establishing that within just a few years a cholesterol-lowering therapy confers a dramatic effect on cardiovascular morbidity and mortality. More recent studies indicate that there is a greater risk reduction in those subjects achieving lower low-density lipoprotein cholesterol (LDL-C) levels--i.e. lower is better. While this favours aggressive therapy, it is nevertheless imperative to precise patients selection for every therapy that entails a major commitment for the patient and medical community. Therefore, well-defined criteria for use of LDL-apheresis have yet to be established in the light of the expanding therapeutic armamentarium. Based on the current knowledge of the impact of statin therapy and anticipating that new options will further optimize the management of dyslipidemia in high-risk patients, we propose a reliable assessment of the effects of LDL-apheresis.

Anticholesteremic Agents↗

PubMed2004

Interactions between fibrinolysis, lipoproteins and leptin related to a first myocardial infarction.

BACKGROUND: The summarized importance of haemostatic and metabolic variables (insulin, lipids including lipoprotein (a) [Lp(a)] and leptin) in predicting first myocardial infarction, as well as possible interactions among these variables, have not been reported. DESIGN: A prospective case-control study nested within the Northern Sweden Health and Disease Cohort. METHODS: Sixty-two men diagnosed with a first myocardial infarction were sex- and age-matched with 124 controls. Conditional logistic regression was conducted including established risk factors, plasma levels of plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator (tPA) mass concentration, von Willebrand factor, insulin, proinsulin, specific insulin, apolipoprotein A-I (apo A-I), Lp(a), and leptin. Interaction analysis was also performed for tPA, apo A-I, Lp(a), leptin and proinsulin. RESULTS: Smoking, low plasma levels of apo A-I and high plasma levels of cholesterol, Lp(a), tPA, PAI-1, proinsulin and leptin were associated with myocardial infarction in univariate conditional logistic regression analysis. High tPA [odds ratio (OR), 21.3; 95% confidence interval (CI), 2.04-222] and Lp(a) (OR, 7.21; 95% CI, 1.31-39.8) and low apo A-I (OR, 0.15; 95% CI, 0.02-0.93) remained significant risk determinants in multivariate analysis with smoking habits, body mass index, hypertension, cholesterol, and diabetes included as covariates. There were non-significant synergic interactions between high Lp(a) and leptin and tPA, respectively, and between high Lp(a) and low apo A-I. CONCLUSION: Plasma levels of tPA, Lp(a), and apo A-I are independently associated with subsequent development of a first myocardial infarction in men.

Apolipoproteins B↗

PubMed2003

A 52-week, multicenter, randomized, parallel-group, double-blind, double-dummy study to assess the efficacy of atorvastatin and simvastatin in reaching low-density lipoprotein cholesterol and triglyceride targets: the treat-to-target (3T) study.

BACKGROUND: Guidelines for the prevention of coronary heart disease call for low-density lipoprotein cholesterol (LDL-C) reduction as the primary target of treatment and reduction of triglycerides (TG) as an additional target. OBJECTIVE: The purpose of this study was to investigate the ability of atorvastatin and simvastatin to reduce LDL-C and TG concentrations and to meet 3 target lipid levels: LDL-C or=4.0 mmol/L (>or=155 mg/dL), were randomized in a 1:1 ratio to receive once-daily oral treatment with 20 mg atorvastatin or 20 mg simvastatin. Fasting (12-hour) blood samples for the estimation of lipid levels and clinical laboratory values were collected after 4, 8, 12, 26, and 52 weeks. The dose was doubled after 12 weeks if the target National Cholesterol Education Program level of LDL-C (<or=2.6 mmol/L [100 mg/dL]) was not reached at 8 weeks. RESULTS: The intent-to-treat analysis included 552 patients (418 men, 134 women) randomized to receive atorvastatin and 535 (404 men, 131 women) randomized to receive simvastatin. The number of patients enrolled in the study allowed the evaluation fo the drugs' effects on TG. Patient demogrpahic characteristics were similar for the 2 treatment groups, and there were no differences in baseline lipid values. Compared with simvastatin, atorvastatin produced significantly greater reductions in LDL-C (8 weeks: -46% vs -40%, P < 0.001; 52 weeks: -49% vs -44%, P < 0.001) and in TG (8 weeks: -23% vs -14%, P < 0.001; 52 weeks: -24% vs -16%, P < 0.001). Compared with simvastatin-treated patients, a significantly greater number of atorvastatin-treated patients reached the LDL-C target after 8 weeks (45% vs 24%; P < 0.001). Fewer atorvastatin patients needed to have their dose doubled; nevertheless more atorvastatin patients reached the LDL-C target after 52 weeks (61% vs 41%; P < 0.001). Both statins were well tolerated. Muscular symptoms occurred in 12 patients (2.2%) in the atorvastatin group and in 13 patients (2.4%) in the simvastatin group. CONCLUSIONS: Atorvastatin 20 or 40 mg/d for up to 1 year of treatment was significantly more effective than simvastatin 20 or 40 mg/d in reducing LDL-C and TG levels and at achieving recommended lipid targets in this selected patient population with cardiovascular disease and dyslipidemia. Both statis were well tolerated.

Adult↗

PubMed2002

Tissue-specific changes in peripheral cortisol metabolism in obese women: increased adipose 11beta-hydroxysteroid dehydrogenase type 1 activity.

Cushing's syndrome and the metabolic syndrome share clinical similarities. Reports of alterations in the hypothalamic-pituitary-adrenal (HPA) axis are inconsistent, however, in the metabolic syndrome. Recent data highlight the importance of adipose 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), which regenerates cortisol from cortisone and, when overexpressed in fat, produces central obesity and glucose intolerance. Here we assessed the HPA axis and 11beta-HSD1 activity in women with moderate obesity and insulin resistance. Forty women were divided into tertiles according to body mass index (BMI; median, 22.0, 27.5, and 31.4, respectively). Serum cortisol levels were measured after iv CRH, low dose dexamethasone suppression, and oral cortisone administration. Urinary cortisol metabolites were measured in a 24-h sample. A sc abdominal fat biopsy was obtained in 14 participants for determination of 11beta-HSD type 1 activity in vitro. Higher BMI was associated with higher total cortisol metabolite excretion (r = 0.49; P < 0.01), mainly due to increased 5alpha- and, to a lesser extent, 5beta-tetrahydrocortisol excretion, but no difference in plasma cortisol basally, after dexamethasone, or after CRH, and only a small increase in the ACTH response to CRH. Hepatic 11beta-HSD1 conversion of oral cortisone to cortisol was impaired in obese women (area under the curve, 147,736 +/- 28,528, 115,903 +/- 26,032, and 90,460 +/- 18,590 nmol/liter.min; P < 0.001). However, 11beta-HSD activity in adipose tissue was positively correlated with BMI (r = 0.55; P < 0.05). In obese females increased reactivation of glucocorticoids in fat may contribute to the characteristics of the metabolic syndrome. Increased inactivation of cortisol in liver may be responsible for compensatory activation of the HPA axis. These alterations in cortisol metabolism may be a basis for novel therapeutic strategies to reduce obesity-related complications.

11-beta-Hydroxysteroid Dehydrogenase Type 1↗