Haitham S. Abu-Lebdeh

Predictive Value of Electrophoretically Detected Lipoprotein(a) for Coronary Heart Disease and Cerebrovascular Disease in a Community-Based Cohort of 9936 Men and Women

BACKGROUND Elevated lipoprotein(a) [Lp(a)] levels have been associated with the presence of atherosclerotic disease. However, the results of prospective studies of Lp(a) and cardiovascular disease have been contradictory. METHODS AND RESULTS From 1968 through 1982, lipoprotein analysis was performed in 11,335 Olmsted County residents. Quantitative cholesterol and triglycerides were obtained along with semiquantitative Lp(a) levels based on electrophoretic pattern. Lp(a) bands were scored from 0 (absent) to 3 (increased). A cohort of 4967 men and 4968 women with no prior history of atherosclerotic disease who had baseline Lp(a) determinations were followed up for 14 years for development of coronary artery disease (CAD) and cerebrovascular disease (CVD). During 131,330 person-years of follow-up, there were 1848 CAD events and 841 CVD events. Age, diabetes, hypertension, cholesterol, and triglycerides were significantly and independently associated with an increased risk of CAD and CVD in men and women. There was a significant increase in the adjusted hazards ratio for CAD with increasing Lp(a) levels for men and women. For Lp(a) level 3, the hazard ratio was 1.9 (range, 1.3 to 2.9) in women and 1.6 (range, 1.0 to 2.5) in men. The adjusted hazard ratio for CVD showed an irregular association with Lp(a) levels in men and no association in women. CONCLUSIONS In this cohort of 9936 men and women initially free of cardiovascular disease who were followed up for 14 years, Lp(a) was a significant predictor of risk of future CAD. Lp(a) was a weak risk factor for CVD in men and was not a significant predictor of CVD risk in women.

Psychosocial Factors and 2-Year Outcome Following Bariatric Surgery for Weight Loss

Background: How psychosocial factors may impact on weight loss after bariatric surgery is not well understood. This lack of knowledge is problematic, because there is a high prevalence of psychosocial distress in patients seeking treatment for obesity in hospital-based programs. The purpose of this study was to examine the relationship between preoperative psychosocial factors and eventual weight loss. Method: Between 1987 and 1998, all individuals undergoing Roux-en-Y gastric bypass for weight loss in our institution had psychologic preoperative evaluations. Patients who were followed prospectively were studied. The relation of having received mental health treatment to percentage of excess weight loss at 2 years is examined using t-tests. Results: 62 women and 18 men completed a 2-year follow-up. Patients who had received treatment for either substance abuse (n=10) or psychiatric co-morbidity (n=39) lost more weight compared with those without such histories (P<0.05, P <0.001 respectively). Conclusion: Given these results, it is plausible that a history of having received either psychiatric treatment for a disorder or counseling for substance abuse should not be a contraindication to bariatric surgery, and, in fact, may be prognostic of favorable outcome. Further research examining psychosocial factors and outcome from bariatric surgery is clearly warranted.

Protein metabolism in diabetes mellitus.

Insulin deficiency is a protein catabolic state. In vivo studies have shown that insulin enhances short-side-chain amino acid intracellular uptake, stimulates transcription and translation of RNA, increases the gene expression of albumin and other proteins and inhibits liver protein breakdown enzymes. In IDDM patients most of the whole-body protein turnover studies have shown that insulin deficiency increases protein breakdown and increases amino acid oxidation and that these effects are reversed by insulin treatment. Recent studies have demonstrated that a substantial increase in leucine transamination during insulin deprivation contributes to leucine catabolism in IDDM patients. Protein synthesis in the insulin-deprived state is also increased although to a lesser extent than protein breakdown, and this increased whole-body protein synthesis is reduced with an insulin infusion; thus the effects of insulin are largely mediated through its effects on protein breakdown. The metabolic derangements in diabetes frequently involve disturbances in substrates and hormones other than insulin. The observed effects of insulin deficiency in diabetic patients vary in different body compartments; most of the effects of insulin on protein synthesis appear to occur in non-muscular tissues especially in the splanchnic area. In addition, insulin has a differential effect on hepatic protein synthesis, i.e. inhibits fibrinogen synthesis and promotes albumin synthesis. Insulins anticatabolic effect in IDDM patients is largely due to its inhibition of protein breakdown. The net protein anabolism due to insulin occurs largely in skeletal muscle. In patients with NIDDM these effects are not noted, presumably because of residual endogenous insulin secretion. In fact, treatments that result in improvement of glucose metabolism in obese NIDDM patients do not affect protein metabolism.

Predictors of Macrovascular Disease in Patients With Type 2 Diabetes Mellitus

OBJECTIVE To assess the importance of classic and nonclassic risk factors in the development of coronary artery disease (CAD) or cerebrovascular disease (CVD) in patients with type 2 diabetes mellitus (DM). PATIENTS AND METHODS In this community-based, prospective cohort study, quantitative measurements for cholesterol, triglycerides (TGs), glucose, and lipoprotein(a) detected as a sinking pre-beta-lipoprotein band on electrophoresis were obtained from 1968 through 1982 from 449 patients who were free of CAD and CVD but had type 2 DM. Demographic data and covariables obtained were age, body mass index, duration of diabetes, sex, smoking, and hypertension. The relationship of individual continuous factors to the development of CAD and CVD as well as multivariate models were evaluated with use of the Cox proportional hazards model. The primary outcome was to determine which risk factors are associated with development of CAD or CVD in patients with type 2 DM. RESULTS After a mean follow-up of 13 years, 216 CAD and 115 CVD events had developed. The hazard ratio estimates with 95% confidence intervals (CIs) for CAD after multivariate analysis were significant for age, 1.45 (95% CI, 1.27-1.67); fasting glucose levels at enrollment, 1.63 (95% CI, 1.17-2.25); smoking, 1.45 (95% CI, 1.10-1.91); and TGs, 1.49 (95% CI, 1.15-1.92). The hazard ratio estimates for CVD were significant for age, 1.95 (95% CI, 1.59-2.38); hypertension, 1.89 (95% CI, 1.30-2.74); fasting glucose levels at enrollment, 1.69 (95% CI, 1.06-2.70); and smoking, 1.57 (95% CI, 1.07-2.30). CONCLUSION In diabetic patients, age, fasting glucose levels, smoking, and TG levels are independent risk factors for development of CAD events. Age, hypertension, glucose, and smoking predicted development of CVD events.

Evaluation and Medical Management of Erectile Dysfunction

Most men older than 60 years experience some degree of erectile dysfunction (ED). The physiology of erections is complex, with contributions from hormonal, vascular, psychological, neurologic, and cellular components. ED is strongly associated with cardiovascular risk factors, and this fact plays a major role in the prevention and treatment of ED. In this article, we review the evaluation of ED in terms of history, physical examination, and common laboratory studies. Additionally, we review major considerations when prescribing phosphodiesterase type 5 inhibitors and other medical treatments, including intraurethral alprostadil, penile injection therapy, and testosterone replacement.

PARATHYROID LIPOADENOMAS: A RARE CAUSE OF PRIMARY HYPERPARATHYROIDISM

OBJECTIVE To review one institutions experience with parathyroid lipoadenomas and to report the associated clinical characteristics. METHODS We present a case series of parathyroid lipoadenomas. A parathyroid lipoadenoma was defined as a single adenoma with more than 50% fat on histologic examination in conjunction with primary hyperparathyroidism and resolution of hypercalcemia postoperatively. Patients who fulfilled the diagnostic criteria were identified from the surgical pathology files of the Mayo Clinic. RESULTS Five cases of parathyroid lipoadenomas, including 1 oxyphil lipoadenoma, were identified during the period from 1971 to 2001. The clinical picture of the study subjects resembled that of a typical patient with primary hyperparathyroidism. Parathyroid lipoadenomas were identified in 3 women (60%) and 2 men (40%), and only 1 patient presented with possible hypercalcemia-related symptoms of nephrolithiasis and hip fracture, leading to diagnosis. The mean serum calcium concentration was 11.1 mg/dL. Preoperatively, all study subjects had elevation of serum parathyroid hormone levels. Two of 3 patients (67%) had the tumor identified preoperatively by neck ultrasonography. CONCLUSION A parathyroid lipoadenoma is a rare cause of primary hyperparathyroidism. The clinical features of this pathologic entity are similar to those of the more common pathologic variants of parathyroid disease associated with primary hyperparathyroidism.

Spontaneous clearance of chronic hepatitis C during pregnancy

TO THE EDITOR: Hepatitis C virus (HCV) infection is prevalent throughout the world, with approximately 4 million infected individuals in the United States alone (1). Spontaneous clearance of HCV after chronic infection has already been established is rare enough to justify individual case reports (2, 3).

Self-perceived vs actual and desired weight and body mass index in adult ambulatory general internal medicine patients: a cross sectional study

BackgroundNo study has compared patients’ self-reported heights and weights (and resultant self-reported body mass indexes [BMIs]) with their actual heights, weights, and BMIs; their self-perceived BMI categories; and their desired weights and BMIs and determined rates of clinicians’ documented diagnoses of overweight and obesity in affected patients in a single patient group. The objectives of this study were to make these comparisons, determine patient factors associated with accurate self-perceived BMI categorization, and determine the frequency of clinicians’ documented diagnoses of overweight and obesity in affected patients.ResultsA total of 508 consecutive adult general internal medicine outpatients (257 women, 251 men; mean age, 62.9 ± 14.9 years) seen at Mayo Clinic in Rochester, Minnesota, between November 9 and 20, 2009, completed a questionnaire in which they reported their heights, weights, self-perceived BMI categories (“underweight,” “about right,” “overweight,” or “obese”), and desired weights. These self-reported data were compared to actual heights, actual weights, and actual BMI categories (measured after the questionnaire was completed). Overall, 70% of the patients were overweight or obese. The average self-reported weight was significantly lower than the average actual weight (80.3 ± 20.1 kg vs 81.9 ± 21.1 kg; P < .001). The average self-reported BMI was significantly lower than the average actual BMI (27.6 ± 5.7 kg/m2 vs 28.3 ± 6.1 kg/m2; P < .001). Overall, 32% of patients had obesity; however, only 6% perceived they were obese. Accuracy of self-perceived BMI category decreased with higher actual BMI category (P < .001 for trend). Female sex, higher education level, smoking status, and lower BMI were associated with higher accuracy of self-perceived BMI category. Desired weight loss increased with higher self-perceived and actual BMI categories (P < .001 for trends). Of the 165 patients who actually were obese, only 40 (24%) had obesity documented as a diagnosis in their medical records by their clinicians. Statistical tests used were the paired t test, the Pearson χ2 test, the Cochrane-Armitage trend test, the Wald test of marginal homogeneity, analysis of variance, and univariate and multivariate logistic regression.ConclusionsMany obese patients inaccurately perceive their BMI categories; accuracy decreases with increasing BMI. Clinicians should inform patients of their BMIs and prescribe treatment plans for those with overweight and obesity.

Does Rimonabant Independently Affect Free Fatty Acid and Glucose Metabolism

CONTEXT Endocannabinoid receptor 1 blockade is proposed to improve metabolic complications of obesity via central and peripheral effects. OBJECTIVE Our objective was to test whether rimonabant improves insulin regulation of free fatty acid and glucose metabolism after controlling for fat loss. DESIGN This was a double-blind, placebo-controlled substudy of the visceral fat reduction assessed by computed tomography scan on rimonabant (VICTORIA) trial. PARTICIPANTS AND SETTING Sixty-seven abdominally obese, metabolic syndrome volunteers age 35-70 yr participated at academic medical center general clinical research centers. INTERVENTION Intervention included a 12-month lifestyle weight management program plus rimonabant 20 mg/d or placebo. MAIN OUTCOME MEASURES Body composition and two-step euglycemic, hyperinsulinemic clamp before and after intervention were performed. Insulin sensitivity was assessed as insulin concentration needed to suppress by 50% palmitate concentration [IC50(palmitate)], flux [IC50(palmitate)f], and hepatic glucose output [IC50(HGO)] and as insulin-stimulated glucose disposal (Δ glucose disappearance per Δ insulin concentration--glucose slope). RESULTS Body fat decreased by 4.5±2.9% (SD) in the rimonabant and 1.9±4.5% in the placebo group (P<0.005). The primary [improvement in IC50(palmitate) and IC50(palmitate)f] and secondary [improvement in IC50(HGO) and glucose slope] outcomes were not significantly different between the rimonabant and placebo groups. Post hoc analyses revealed that 1) changes in body mass index (BMI) and IC50(palmitate) were correlated (P=0.005) in the rimonabant group; this relationship was not significantly different from placebo when controlling for greater BMI loss (P=0.5); 2) insulin-regulated glucose disposal improved in both groups (P=0.002) and correlated with changes in BMI. CONCLUSIONS Improvements observed in insulin regulation of free fatty acid and glucose metabolism with rimonabant treatment in humans was not greater than that predicted by weight loss alone.

Suppressibility of parathyroid hormone in primary hyperparathyroidism.

OBJECTIVE To describe an unusual case of pathologically confirmed primary hyperparathyroidism in a patient presenting with severe hypercalcemia and an undetectable parathyroid hormone (PTH) level. METHODS We present a detailed case report and outline the serial laboratory findings. In addition, the possible causes of low serum PTH levels in the setting of primary hyperparathyroidism are discussed. RESULTS A 16-year-old female patient presented with severe epigastric pain, found to be attributable to acute pancreatitis. At hospital admission, her serum calcium concentration was high (14.0 mg/dL); the patient also had a normal serum phosphorus level of 3.6 mg/dL and an undetectable PTH level (<0.2 pmol/L). An evaluation for non-PTH-mediated causes of hypercalcemia revealed a partially suppressed thyroid-stimulating hormone concentration and a below normal 1,25-dihydroxyvitamin D level, consistent with her suppressed PTH. One week after the patient was dismissed from the hospital, repeated laboratory studies showed a serum calcium value of 11.1 mg/dL, a serum phosphorus level of 2.8 mg/dL, and an elevated PTH concentration of 11.0 pmol/L, consistent with primary hyperparathyroidism. A repeated 1,25-dihydroxyvitamin D measurement was elevated. A parathyroid scan showed a parathyroid adenoma in the left lower neck area, and she subsequently underwent successful surgical resection of a pathologically confirmed parathyroid adenoma. CONCLUSION This case demonstrates that the serum PTH level can be suppressed in patients with primary hyperparathyroidism. Moreover, it emphasizes the need for careful evaluation of the clinical context in which the PTH measurement is determined. Consideration should be given to repeating measurement of PTH and serum calcium levels when the initial laboratory evaluation of hypercalcemia is unclear because dynamic changes in calcium metabolism may occur in the presence of secondary contributing factors.