Insulin counter-regulatory factors, fibrinogen and C-reactive protein during olanzapine administration: effects of the antidiabetic metformin

In this study, the Authors assessed some insulin counter-regulatory factors, fibrinogen and C-reactive protein after olanzapine administration, and the effect of metformin on these variables, 37 patients with chronic schizophrenia were given olanzapine (10 mg/day for 14 weeks). Nineteen patients received metformin (850-2550 mg/day) and 18 received placebo in a randomized, double-blind protocol. The following variables were quantified before and after olanzapine: cortisol, leptin, tumor necrosis factor-alpha, glucagon, growth hormone, fibrinogen and C-reactive protein. Results were correlated with the changes in body weight and the insulin resistance index. We have reported elsewhere that metformin did not prevent olanzapine-induced weight gain, and the insulin resistance index significantly decreased after metformin and placebo; Baptista T, et al. Can J Psychiatry 2006; 51: 192-196. Cortisol, tumor necrosis factor-alpha and fibrinogen levels significantly decreased in both groups. Glucagon significantly increased after metformin (P=0.03). Leptin tended to increase after placebo (P=0.1) and displayed a small nonsignificant reduction after metformin. The C-reactive protein did not change significantly in any group. Contrarily to most published studies, olanzapine was associated with decreased insulin resistance. Decrements in cortisol, fibrinogen and tumor necrosis factor-alpha levels point to an improvement in the metabolic profile. The trend for leptin to increase after placebo, but not after metformin in spite of similar weight gain suggests a beneficial effect of this antidiabetic agent.

Acute effects of atypical antipsychotics on whole-body insulin resistance in rats: implications for adverse metabolic effects

Although it is generally accepted that atypical antipsychotics differ in their risk for diabetic side effects, the underlying pharmacological mechanisms are unknown. Studies on the mechanisms of antipsychotic-induced hyperglycemia or insulin resistance are often confounded by the concomitant weight gain and dyslipidemia, known diabetic risk factors. To investigate whether antipsychotics can acutely cause metabolic effects before any change in body composition, we studied the effects of four atypical antipsychotics on whole-body insulin resistance. Using the hyperinsulinemic, euglycemic clamp technique in conscious rats, insulin and somatostatin were infused at a constant rate to provide constant hyperinsulinemia and to suppress pancreatic insulin secretion. Glucose was infused at a variable rate, adjusted to maintain euglycemia. At steady state, animals were administered vehicle (V) or antipsychotic and the glucose infusion rate was monitored as an index of insulin sensitivity. Clamp experiments using radiotracers and studies on glucose uptake into isolated skeletal muscle were conducted to differentiate between effects on hepatic glucose production (HGP) and on peripheral glucose uptake. Olanzapine (OLAN) and clozapine (CLOZ) acutely impaired whole-body insulin sensitivity in a dose-dependent manner (P<0.001 vs V), whereas ziprasidone and risperidone had no effect. CLOZ also induced profound insulin resistance after dosing 10 mg/kg/day for 5 days (P<0.05 vs V). Tracer studies indicated that acute changes mainly reflect increased HGP, consistent with the lack of effect on glucose uptake. OLAN and CLOZ can thus rapidly induce marked insulin resistance, which could contribute to the hyperglycemia and ketoacidosis reported for patients receiving those therapies.

Cardiovascular and metabolic risk in outpatients with schizophrenia treated with antipsychotics: results of the CLAMORS Study

AIM

To assess the prevalence of Coronary Heart Disease (CHD) and Metabolic Syndrome (MS) in patients treated with antipsychotics.

METHODS

Retrospective, cross-sectional, multicenter study in which 117 Spanish psychiatrists (the CLAMORS Study Collaborative Group) recruited consecutive outpatients meeting DSM-IV criteria for Schizophrenia, Schizophreniform or Schizoaffective Disorder, receiving antipsychotic treatment for at least 12 weeks. CHD risk was assessed by SCORE (10-year CV death) and Framingham (10-year all CHD events) function. MS was defined by at least 3 of the following components: waist circumference >102 (men)/>88 (women) cm; triglycerides > or =150 mg/dl; HDL-cholesterol <40 mg/dl (men)/<50 mg/dl (women); blood pressure > or =130/85; fasting glucose > or =110 mg/dl.

RESULTS

1452 evaluable patients (863 men, 60.9%), aged 40.7+/-12.2 years (mean+/-SD) were included. MS was present in 24.6% [23.6% (men), 27.2% (women); p=0.130)]. The overall 10-year risks were 0.9+/-1.9 (SCORE) and 7.2+/-7.6 (Framingham). 8% (95%CI: 6.5-9.5) and 22.1% (95%CI: 20.0-24.3) of patients showed a high/very high risk according to SCORE (> or =3%) and Framingham (> or =10%) function. Abdominal obesity and low HDL-cholesterol were more prevalent in women: 54.5% (95%CI: 50.2-58.9) versus 34.3% (95%CI: 31.0-37.7), and 46.1% (95%CI: 41.4) versus 28.5 (95%CI: 50.8), p<0.001 in both cases. Hypertension and hypertriglyceridemia were more prevalent in men: 59.0% (95%CI: 55.7-62.3) versus 46.0% (95%CI: 41.8-50.2), and 40.7% (95%CI: 37.2-44.2) versus 32.4 (95%CI: 28.3-36.5), p<0.01 in both cases.

CONCLUSIONS

CHD risk and MS prevalences among patients with schizophrenia treated with antipsychotics were in the same range as the Spanish general population 10 to 15 years older.

Effect of PPAR-gamma agonist on adiponectin levels in the metabolic syndrome: lessons from the high fructose fed rat model

BACKGROUND

The health hazard of the metabolic syndrome (MS) is increasing, yet there is no effective pharmacologic treatment to this entity as a whole. Recently, hypoadiponectinemia was found to play an important role in the development of MS. We studied the effect of the PPAR-gamma agonist rosiglitazone on adiponectin and the metabolic profile in the fructose-induced hypertensive, hyperinsulinemic, hypertriglyceridemic rat model.

METHODS

Thirty male Sprague-Dawley rats were divided into three groups. Ten were fed standard rat chow for 5 weeks, 10, a fructose-enriched diet for 5 weeks, and 10, a fructose-enriched diet for 5 weeks, with rosiglitazone 10 mg/kg/d added during the last 2 weeks. Blood pressure (BP), oral glucose tolerance test (OGTT), plasma insulin, triglycerides, and adiponectin were recorded, as well as mRNA levels of the adiponectin gene in visceral adipose tissue.

RESULTS

Fructose-fed rats developed MS as manifested by the increase in systolic BP (from 139 +/- 3 to 158 +/- 4 mm Hg, P < .05), insulin (from 26 +/- 1.6 to 40 +/- 2.5 muU/mL, P < .05), triglycerides (from 91 +/- 9 to 304 +/- 24 mg/dL, P < .05), and impaired OGTT (area under the curve from 13,894 +/- 246 to 17,725 +/- 700 mg/dL/min). Treatment with rosiglitazone reversed these effects and reduced BP to 133 +/- 7 mm Hg, insulin levels to 30 +/- 2.8 muU/mL, triglycerides to 116 +/- 9 mg/dL, and the OGTT to 15,415 +/- 372 mg/dL/min (P < .05 for all variables). In addition, rosiglitazone increased plasma levels of adiponectin fourfold from 4.3 +/- 0.1 to 18.4 +/- 0.6 mug/mL (P < .05). This increase was coupled with 3.8-fold increase in adiponectin mRNA in visceral adipose tissue.

CONCLUSIONS

This study shows for the first time that in an animal model of MS, the insulin sensitizer, rosiglitazone, improves the metabolic profile and increases plasma levels of adiponectin and its gene expression. It is possible therefore that rosiglitazone exerts its beneficial effects by increasing the levels of adiponectin.

Differential pharmacology of atypical antipsychotics: Clinical implications

PURPOSE

Pharmacology of atypical antipsychotics and the clinical implications are reviewed.

SUMMARY

Psychiatric disorders, such as schizophrenia and bipolar disorder, are often associated with poor outcomes. Atypical antipsychotics have become the standard of care for these disorders, and multiple agents have demonstrated efficacy for both acute and maintenance therapy. As a result of their differential pharmacologic properties, atypical antipsychotics have diverse clinical profiles, resulting in different liabilities for specific adverse events. These effects can, in turn, have an adverse impact on patient functionality, adherence to therapy, and overall health.

CONCLUSION

Atypical antipsychotics have distinct pharmacological profiles which result in clinically meaningful differences in adverse effects. Clinicians should have a wide choice of agents available with which to optimize outcomes in the majority of patients with psychiatric disorders.

Awareness of metabolic concerns and perceived impact of pharmacotherapy in patients with bipolar disorder: a survey of 500 US psychiatrists

OBJECTIVE

An online survey was conducted to assess psychiatrists' familiarity with the metabolic syndrome and its components in patients with bipolar disorder, and characterize their perspectives and practices regarding its impact on patient management.

METHODS

Participants were US psychiatrists from a random sample of those in the AMA database. Qualified respondents practiced 4-30 years, spent > or = 50% of their time in direct patient care, and treated > or = 25 bipolar patients in the last month. Results were collected and tabulated by Harris Interactive from Nov-Dec 2005.

RESULTS

Five hundred psychiatrists qualified and completed the survey, and 50 respondents also participated in follow-up interviews. Most respondents (94%) viewed metabolic syndrome as a significant health risk requiring monitoring and treatment. While 76% have diagnosed it, only 28% correctly identified the five NCEP diagnostic criteria. Medication adverse effects of greatest concern were weight gain, glucose intolerance, and dyslipidemia. During treatment, 78% of respondents reported monitoring weight, 69% glucose, 61% lipids, and 52% blood pressure. Most respondents (92%) reported referring patients to specialists or primary care for metabolic abnormalities. Changes in metabolic profile were reported to prompt many psychiatrists (85%) to stop or switch bipolar medications, especially those who treat a large number of bipolar patients (89%). The follow-up interviews supported a change in practice patterns over the last 5 years.

CONCLUSIONS

Nearly all respondents have metabolic concerns with medical therapies used to treat bipolar disorder. Many now routinely monitor weight and other metabolic parameters. Most have referred patients for medical management and adjusted bipolar therapies due to metabolic abnormalities.

Does antipsychotic polypharmacy increase the risk for metabolic syndrome?

OBJECTIVE

To determine whether the coprescribing of two or more antipsychotics, a relatively frequent practice with little data to support its safety and efficacy, is associated with an increased prevalence of metabolic syndrome.

METHODS

364 newly admitted adults treated with second-generation antipsychotics underwent assessments evaluating antipsychotic polytherapy, and of the presence of metabolic syndrome and triglycerides/high-density lipoprotein cholesterol ratio>3.5 (TG/HDL), a sensitive marker of insulin resistance. The correlates of antipsychotic polytherapy and associations with metabolic syndrome and TG/HDL were determined by univariate comparisons and multiple logistic regression analyses.

RESULTS

Antipsychotic polytherapy was present in 70 patients (19.2%) and was significantly more likely in patients with schizophrenia and those treated with clozapine, quetiapine or ziprasidone (p<0.0001). Compared with antipsychotic monotherapy, polytherapy was associated with elevated rates of metabolic syndrome (50.0% vs. 34.3%, p=0.015) and TG/HDL (50.7% vs. 35.0%, p=0.016). However, in logistic regression analyses, metabolic syndrome was significantly associated with higher body mass index (BMI), older age, a diagnosis of bipolar disorder or schizophrenia, and cotreatment with a first-generation antipsychotic (r(2): 0.25, p<0.0001). The TG/HDL marker of insulin resistance was associated with higher BMI, male sex, Caucasian race and absence of aripiprazole treatment (r(2): 0.14, p<0.0001). Antipsychotic polypharmacy dropped out of both multivariate models.

CONCLUSIONS

Compared with patients receiving antipsychotic monotherapy, patients on antipsychotic polytherapy have higher rates of metabolic syndrome and lipid markers of insulin resistance. However, antipsychotic polytherapy is not independently associated with the prevalence of these abnormalities, which are related to known demographic, clinical and anthropometric risk factors.

Signs and symptoms associated with the metabolic syndrome in psychiatric inpatients receiving antipsychotics: a retrospective chart review

OBJECTIVE

The metabolic syndrome has been recognized as a major health risk for patients taking atypical antipsychotics. Few studies, however, have examined large samples of psychiatric patients to explore the prevalence of the signs and symptoms associated with this condition.

METHOD

The investigators retrospectively identified all inpatient admissions at the study site who were treated with antipsychotics during 2003 (N = 1691) and extracted demographic and clinical data (including measures associated with the syndrome: body mass index > 30 kg/m2, dyslipidemia, diagnosis of hypertension or diabetes). Stepwise logistic regression was used to identify variables associated with each correlate of the syndrome.

RESULTS

In the majority of this sample (69.3%), at least 1 correlate of the metabolic syndrome was present. The odds that a patient would have 1 or more of these measures were approximately 8 times greater for those receiving clozapine than for those receiving another anti-psychotic medication. These patients also had increased odds (odds ratio = 2.5) of having hypertension or diabetes. In the subsample of patients with documentation for all 5 correlates of the metabolic syndrome (N = 362), 18.8% had > or = 3 of 5.

CONCLUSION

The prevalence of at least 3 correlates in psychiatric inpatients receiving antipsychotics is probably an underestimate, because diagnosis was substituted for the blood pressure and glucose measures. Nonetheless, these findings support the call for routine screening for metabolic symptoms in patients receiving antipsychotics. The risk for these symptoms may be particularly high in some subgroups identified, such as patients older than 50 years and those taking clozapine or multiple antipsychotics.

[Metabolic disturbances associated with HAART]

HAART changed natural course of infection with HIV, reduced the morbidity and mortality of AIDS patients. The lipodystrophy syndrome is long-term complication of antiretroviral therapy characterized by changes in body fat redistribution changes and metabolic abnormalities: insulin resistance, hyperglycemia, diabetes type 2, hypertriglyceridemia and hyperlipidemia. The pathogenesis is multifactorial due to interplay of viral, host and drug related factors. The HIV protease inhibitors and NRTI may play a pathogenic role. The potential risk factors include treatment with PIs and NTRIs, increasing age, gender and genetic predispositions.

The art and science of switching antipsychotic medications, part 2

In the presentation "Switching and Metabolic Syndrome," Weiden summarizes reasons to switch antipsychotics, highlighting weight gain and other metabolic adverse events as recent treatment targets. In "Texas Medication Algorithm Project (TMAP)," Miller reviews the TMAP study design, discusses results related to the algorithm versus treatment as usual, and concludes with the implications of the study. Lambert's presentation, "Dosing and Titration Strategies to Optimize Patient Outcome When Switching Antipsychotic Therapy," reviews the decision-making process when switching patients' medication, addresses dosing and titration strategies to effectively transition between medications, and examines other factors to consider when switching pharmacotherapy.

Second-generation antipsychotics: is there evidence for sex differences in pharmacokinetic and adverse effect profiles?

Six second-generation antipsychotics (SGAs), aripiprazole, clozapine, olanzapine, quetiapine, risperidone and ziprasidone, are currently US FDA approved. The aim of this review is to investigate whether sex differences exist for efficacy and adverse effects of these drugs.Sex-related differences have been shown in the pharmacokinetics of cytochrome P450 (CYP), with a higher activity in females for CYP3A4 and CYP2D6. However, even if there are pharmacokinetic differences between females and males, significantly higher plasma concentrations in women have been demonstrated only for olanzapine and clozapine. To date, sex differences in adverse effects have not been well studied, but some adverse effects such as weight gain, hyperprolactinaemia and cardiac effects are reported to be particularly problematic for women. Most of the studies reviewed indicate that clozapine and olanzapine are associated with greater bodyweight gain than the other atypical antipsychotics, and that serious adverse effects such as metabolic syndrome, which includes increased visceral adiposity, hyperglycaemia, hypertension and dyslipidaemia induced by SGAs, are more frequent in females. According to most studies, the risk for cardiac adverse effects induced by SGAs is the same in male and female patients. Although women are at a lower risk of sudden cardiac death, they have a higher risk of induced long QT syndrome from antiarrhythmic and, probably, antipsychotic drugs. The propensity of sexual dysfunctions is higher with conventional antipsychotics than with SGAs. Additionally, there is some evidence that female sexual dysfunction is associated with high prolactin levels; however, whether the degree of prolactin level elevation is different between female and male patients remains controversial. There is no evidence for sex differences for any of the SGAs to cause a higher rate of extrapyramidal symptoms, acute dystonia or any other movement disturbance. Knowledge of the risks and benefits associated with the use of SGAs during pregnancy and lactation is limited, although the direction of dose adjustments during pregnancy depends on the drug and the enzyme that is responsible for its metabolism. In general, data on sex differences were mostly obtained by posthoc analysis and, therefore, the conclusions that can be drawn are limited. For a better understanding of the basic mechanisms of sex differences, future studies with a primary focus on this topic are required. Data that are more specific will help determine the extent to which these differences will have implications for clinical management.

Obesity, dyslipidemia, and diabetes with selective serotonin reuptake inhibitors: the Hordaland Health Study

OBJECTIVE

This study aimed to examine whether subjects taking selective serotonin reuptake inhibitors (SSRIs) are more likely to have elements of the metabolic syndrome compared with those taking no psychotropic drugs. For comparison, we also studied subjects taking antipsychotic drugs.

METHOD

We used data from The Hordaland Health Study '97-'99, a general community cross-sectional health survey including 25,315 subjects aged 40 to 49 and 70 to 74 years. For the groups studied, we estimated prevalence and odds ratios (ORs) for obesity, hypercholesterolemia, low high-density lipoprotein cholesterol, hyper-triglyceridemia, and diabetes.

RESULTS

We observed an association between use of SSRIs as a group (N = 461) and abdominal obesity (OR = 1.40, 95% CI = 1.08 to 1.81) and hypercholesterolemia (OR = 1.36, 95% CI = 1.07 to 1.73) after adjusting for multiple possible confounders. There was also a trend toward an association between SSRI use and diabetes. In a subgroup analysis of subjects taking SSRIs, the use of paroxetine (N = 187) was markedly associated with both general and abdominal obesity but not with hypercholesterolemia. In contrast, the use of citalopram (N = 142) was not associated with any of the metabolic outcome variables, while the use of any other SSRI (sertraline, fluoxetine, or fluvoxamine) (N = 131) as a mixed subgroup was associated with both abdominal obesity and hypercholesterolemia. We also replicated the previously reported associations between use of antipsychotics and obesity and metabolic disturbances.

CONCLUSION

We have shown that use of at least some SSRIs is associated with clinical and biochemical elements of the metabolic syndrome. Our data indicate differences in the metabolic side effect profile among various SSRI drugs, although treatment bias might have influenced these results. We suggest that patients taking SSRIs be carefully monitored for obesity and dyslipidemia.

Arzneimittelnebenwirkungen bei antiretroviraler Therapie

The introduction of highly active antiretroviral therapy (HAART) has resulted in tremendous improvements in morbidity and mortality in HIV-infected patients. However, the use of these drugs has coincided with an increasing number of reports of gastrointestinal, hepatic or metabolic side effects. Soon after beginning antiretroviral treatment drug rashes, hypersensitivity reactions, immune reconstitution syndrome or injection site reaction are frequently seen. Under HAART dyslipidemia, impaired glucose metabolism and elevated liver function are observed. In the later treatment phase, lipodystrophy, a combination of peripheral lipoatrophy and central fat accumulation, occurs.

Oral treatment and in vitro incubation with fructose modify vascular prostanoid production in the rat

1.-- In the rat, a fructose-enriched diet induces hyperglycaemia, hypertriglyceridaemia, insulin resistance and hypertension; a model which resembles the human metabolic syndrome. 2.-- Prostanoids, metabolites of arachidonic acid, include vasoactive substances synthesized and released from the vascular wall that have been implicated in the increase of peripheral resistance, one of the mechanisms involved in the fructose-induced hypertension. 3.-- The aim of the present study was to: (i) analyse the effects of the in vitro incubation with fructose on the production and release of prostanoids in rat thoracic aorta and in rat mesenteric bed and (ii) compare the effects of incubation with those of the in vivo acute and chronic treatment of rats with fructose and with the combination of both in vivo and in vitro procedures. 4.-- Blood pressure, glycaemia and triglyceridaemia were significantly elevated in both 4- and 22-week fructose-treated groups. Meanwhile, body and heart weight as well as insulinaemia were similar between experimental animals and controls. 5.-- In aortae, 4 weeks of Fructose treatment did not modify the prostanoid pattern release, but in vitro incubation decreased prostacyclin (PGI(2)) production. However, after 22 weeks, fructose treatment and incubation exerted the same effect. 6.-- In mesenteric bed, after 4 weeks, the incubation and the combination of both procedures reduced the release of the vasodilators PGI(2) and PGE(2), while fructose treatment only diminished the PGE(2) release. On the contrary, the production of the vasoconstrictor thromboxane A(2) (TXA(2)) was enhanced by incubation and both the procedures. After 22 weeks, fructose treatment increased PGI(2) release, while it was reduced by incubation. The combination of both did not modify this peripheral resistance when compared with controls. Finally, incubation of tissues from treated rats increased the release of the vasoconstrictors, PGF(2alpha) and TXA(2). 7.-- In conclusion, the mesenteric bed, a resistance vascular bed, seems to be more sensitive than the aorta, a conductance vessel, to the effects of fructose on prostanoid production. This difference could be related to a more relevant role of resistance vessels in the regulation of peripheral resistance and consequently of blood pressure. The observed effects should contribute to a shift in the balance of the release of prostanoid in favour of vasoconstrictor metabolites. This phenomenon could be related to an increase in the peripheral resistance and the mild hypertension observed in the fructose-treated rats.

Medical risk in patients with bipolar disorder and schizophrenia

Patients with schizophrenia and bipolar disorder are vulnerable to developing key modifiable risk factors for cardiovascular disease, such as obesity, smoking, hypertension, dyslipidemia, and type 2 diabetes mellitus. In addition, mood stabilizers, anticonvulsants, and antipsychotic medications, which are commonly used to treat schizophrenia and bipolar disorder, have been linked to risk for adverse metabolic changes in patients. This article reviews the current literature on the prevalence of medical risk factors in the general population as well as in those patients with schizophrenia or bipolar disorder and discusses treatment strategies and lifestyle changes that patients can make in order to reduce their risks for certain diseases.

Acetaldehyde promotes rapamycin-dependent activation of p70(S6K) and glucose uptake despite inhibition of Akt and mTOR in dopaminergic SH-SY5Y human neuroblastoma cells

Alcohol intake is one of the important lifestyle factors for the risk of insulin resistance and type 2 diabetes. Acetaldehyde, the major ethanol metabolite which is far more reactive than ethanol, has been postulated to participate in alcohol-induced tissue injury although its direct impact on insulin signaling is unclear. This study was designed to examine the effect of acetaldehyde on glucose uptake and insulin signaling in human dopaminergic SH-SY5Y cells. Akt, mammalian target of rapamycin (mTOR), ribosomal-S6 kinase (p70(S6K)), the eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1) and insulin receptor substrate (IRS)-2 were evaluated by Western blot analysis. Glucose uptake and apoptosis were measured using [(3)H]-2-deoxyglucose uptake and caspase-3 assay, respectively. Short-term exposure (12 h) of acetaldehyde (150 muM) facilitated glucose uptake in a rapamycin-dependent manner without affecting apoptosis, IRS-2 expression and insulin-stimulated glucose uptake in SH-SY5Y cells. Acetaldehyde suppressed basal and insulin-stimulated Akt phosphorylation without affecting total Akt expression. Acetaldehyde inhibited mTOR phosphorylation without affecting total mTOR and insulin-elicited response on mTOR phosphorylation. Rapamycin, which inhibits mTOR leading to inactivation of p70(S6K), did not affect acetaldehyde-induced inhibition on phosphorylation of Akt and mTOR. Interestingly, acetaldehyde enhanced p70(S6K) activation and depressed 4E-BP1 phosphorylation, the effect of which was blunted and exaggerated, respectively, by rapamycin. Collectively, these data suggested that acetaldehyde did not adversely affect glucose uptake despite inhibition of insulin signaling cascade at the levels of Akt and mTOR, possibly due to presence of certain mechanism(s) responsible for enhanced p70(S6K) phosphorylation.

Lipid monitoring in patients with schizophrenia prescribed second-generation antipsychotics

OBJECTIVES

Treatment with second-generation antipsychotic (SGA) medications has been linked with increased rates of the metabolic syndrome (i.e., dyslipidemia, obesity, and hyperglycemia). Several sets of published recommendations now provide clinicians with guidelines for monitoring metabolic parameters in individuals with schizophrenia treated with SGAs. However, few data are available regarding actual metabolic monitoring practices in this patient population. The objectives of the study were to determine baseline lipid monitoring rates for individuals with schizophrenia prescribed SGAs during the period prior to the publication of monitoring guidelines and to determine whether individuals with abnormal lipid levels received follow-up monitoring sooner than individuals with normal levels.

METHOD

Lipid monitoring rates for 408 individuals with schizophrenia who were prescribed SGAs from October 1999 to October 2003 were examined using administrative data from a Veterans Affairs facility. Survival analysis was used to examine time to follow-up lipid measurement and to compare time to follow-up measure for individuals with normal initial lipid levels versus those with elevated initial lipid levels.

RESULTS

Eighty-five percent of individuals had at least 1 measurement for total cholesterol or triglycerides in a 4-year period. Abnormal initial measurements predicted significantly earlier follow-up monitoring (p < .005 for total cholesterol, p < .05 for triglycerides, p < .001 for low-density lipoprotein cholesterol). However, median time to follow-up measure was 304 days (approximately 10 months) for individuals with elevated total cholesterol levels, which is too long for optimal clinical follow-up.

CONCLUSION

Program managers and clinicians should assess adequacy of monitoring and support quality improvement initiatives in this area.

Long term excessive Zn-supplementation promotes metabolic syndrome-X in Wistar rats fed sucrose and fat rich semisynthetic diet

During the last two decades Zinc (Zn) as a micronutrient is being used indiscriminately in agricultural and husbandry practices and also in baby foods and multivitamin supplements with a view that Zn is non-toxic and promotes linear growth and body weight in the consumers. The long-term effect of increasing Zn load in the body has not been worked out so far. In this study, three groups of rats were fed on a semi-synthetic diet containing 20 mg (control, group-I), 40 mg (group-II) and 80 mg Zn /kg (group-III) diet respectively for 6 months. The results revealed that the gain in body weight increased in rats in Zn-concentration dependent manner. The urine examined on weekly basis showed glucosuria in group-II on week 10 and in group-III on week 8 and thereafter. The arterial blood pressure was significantly higher in group-II and III than their control counter parts on monthly basis. Histochemical examination of skin revealed an increase in the number of adipocytes filled with triglycerides making a subcutaneous fatty tissue thicker in group-II and group-III than that of control group. The blood profile after 180 days of dietary treatment, displayed a significant rise in glucose, total lipids, cholesterol, triglycerides, LDL-cholesterol, VLDL-cholesterol, insulin, cortisol and aldosterone whereas HDL-cholesterol, T3, T4 and TSH showed a reduction in their levels in the blood serum. The tissue metal status showed an increase of Zn, Cu and Mg in the serum, a rise in Zn in liver, hair and abdominal muscles and fall in Cu and Mg concentrations in liver, hair and abdominal muscles. This data suggest that Zn in excess in diet when fed for longer periods of time induces metabolic syndrome-X.

Metabolic and Cardiovascular Effects of Smokeless Tobacco

The nation's largest cigarette companies are selling more smokeless tobacco (ST) products as more cities and states pass smoke-free laws. ST use is already common and is expected to get more popular as a result of these recent changes. Unfortunately, the medical and public knowledge of its risks is inadequate. The literature on the cardiovascular side effects of ST is scant, and there are many controversies associated with its use, for various reasons. Study findings show that ST may modestly increase cardiovascular mortality and produces transient changes in heart rate and blood pressure; however, it does not increase the risk of atherosclerosis or myocardial infarction. The association between ST and diabetes, lipoproteins, and stroke is less clear. Quitting ST causes weight gain, but less so than smoking. Although ST appears to be associated with less cardiovascular risk than smoking, nicotine replacement therapy is a safer and more controlled substitute for smoking than ST; however, ST can be considered in high-risk smokers in whom medicinal nicotine replacement therapy has failed.

Fructose-induced metabolic syndrome is associated with glomerular hypertension and renal microvascular damage in rats

Fructose intake has been recently linked to the epidemic of metabolic syndrome and, in turn, the metabolic syndrome has been epidemiologically linked with renal progression. The renal hemodynamic effects of fructose intake are unknown, as well as the effects of different routes of administration. Metabolic syndrome was induced in rats over 8 wk by either a high-fructose diet (60%, F60, n = 7) or by adding fructose to drinking water (10%, F10, n = 7). Body weight and food and fluid intake of each rat were measured weekly during the follow-up. At baseline and at the end of wk 8, systolic blood pressure, plasma uric acid, and triglycerides were measured. At the end of week 8 glomerular hemodynamics was evaluated by micropuncture techniques. Wall thickening in outer cortical and juxtamedullary afferent arterioles was assessed by immunohistochemistry and computer image analysis. Fructose administration either in diet or drinking water induced hypertension, hyperuricemia, and hypertriglyceridemia; however, there was a progressive increment in these parameters with higher fructose intake (C<F10<F60). In addition, the F60 rats developed kidney hypertrophy, glomerular hypertension, cortical vasoconstriction, and arteriolopathy of preglomerular vessels. In conclusion, fructose-induced metabolic syndrome is associated with renal disturbances characterized by renal hypertrophy, arteriolopathy, glomerular hypertension, and cortical vasoconstriction. These changes are best observed in rats administered high doses (60% diet) of fructose.

HIGH-FAT FEEDING REDUCES ENDOTHELIUM-DEPENDENT VASODILATION IN RATS: DIFFERENTIAL MECHANISMS FOR SATURATED AND UNSATURATED FATTY ACIDS?

1. Chronic feeding with a high-fat diet can cause metabolic syndrome in rodents similar to humans, but the role of saturated versus unsaturated fats in vascular tension remains unclear. 2. The present study shows that rats on a diet rich in either saturated or unsaturated fat had higher blood pressure compared with chow-fed rats (approximately 130 vs 100 mmHg, respectively), along with hyperlipidaemia and insulin resistance. Compared with responses of phenylephrine-preconstricted artery segments from chow-fed rats, vasorelaxation of isolated renal arteries from high-fat fed rats was reduced substantially (> 50%) in response to acetylcholine (0.01-10 micromol/L) and moderately to nitroprusside (>or=1 micromol/L) at low concentrations. Acetylcholine-induced vasorelaxation of arteries from high-fat fed rats was also more sensitive to inhibition by the nitric oxide (NO) synthase inhibitors NG-nitro-L-arginine and methylene blue. 3. In human umbilical vein endothelial cells, the production of NO and endothelin-1 was significantly inhibited by unsaturated fatty acids. In comparison, saturated fatty acids stimulated endothelin-1 production without altering NO production. 4. The data indicate that both saturated and unsaturated high-fat feeding may result in an increase in blood pressure owing to reduced endothelium-dependent vasorelaxation in the arterial system. The impaired endothelium-dependent vasorelaxation induced by saturated and unsaturated fatty acids may involve different mechanisms.

Effects of typical and atypical antipsychotics on glucose-insulin homeostasis and lipid metabolism in first-episode schizophrenia

RATIONALE

Glucose and lipid metabolism dysfunction is a significant side effect associated with antipsychotics. Although there are many studies about the linkages between drugs and metabolic dysfunction, most of these studies have compared the effects of two antipsychotics on only one metabolic measure: either glucose or lipid metabolism.

OBJECTIVES

The present study aimed to investigate the effects of clozapine, olanzapine, risperidone, and sulpiride on glucose and lipid metabolism in first-episode schizophrenia.

MATERIALS AND METHODS

One hundred twelve schizophrenics were assigned randomly to receive clozapine, olanzapine, risperidone, or sulpiride for 8 weeks. Planned assessments included body mass index (BMI), waist-to-hip ratio, fasting glucose, insulin, C-peptide, insulin resistance index (IRI), cholesterol, and triglyceride. All measures were collected at baseline and at the end of the 8-week treatment.

RESULTS

After treatment, insulin, C-peptide, and IRI were significantly increased in the four groups, but not fasting glucose levels. Cholesterol and triglyceride levels were significantly increased in the clozapine and olanzapine groups. Patients treated with clozapine and olanzapine had higher fasting insulin, C-peptide, and IRI levels than those treated with risperidone and sulpiride. Among the four antipsychotics, the increases of mean BMI from high to low were as follows: clozapine, olanzapine, sulpiride, and risperidone.

CONCLUSIONS

This study confirmed that the four antipsychotic drugs were associated with an increase of insulin, C-peptide, and IRI. It was found that clozapine and olanzapine were associated with an increase in cholesterol and triglyceride levels. The effects of clozapine and olanzapine on the glucose and lipid metabolism outweighed those of risperidone and sulpiride.

Recombinant methionyl human leptin therapy in replacement doses improves insulin resistance and metabolic profile in patients with lipoatrophy and metabolic syndrome induced by the highly active antiretroviral therapy

CONTEXT

Highly active antiretroviral therapy (HAART) for HIV-1 infection has been associated with a metabolic syndrome characterized by insulin resistance, hyperlipidemia, and redistribution of body fat (lipodystrophy). A subset of patients with predominant lipoatrophy has low levels of the adipocyte-secreted hormone leptin.

OBJECTIVE

The objective of the study was to assess whether administration of recombinant methionyl human leptin (r-metHuLeptin) improves insulin resistance and other metabolic abnormalities in HIV+ leptin-deficient subjects with HAART-induced lipoatrophy.

DESIGN, SETTING, PATIENTS, AND INTERVENTION

We conducted a randomized, placebo-controlled, double-blinded, crossover study from 2002 to 2004 in seven HIV+ men with HAART-induced lipoatrophy, serum leptin level less than 3 ng/ml, and fasting triglyceride level greater than 300 mg/dl, who were administered placebo for 2 months before or after administration of r-metHuLeptin at physiological doses for an additional 2 months.

MAIN OUTCOME MEASURES

Insulin resistance, lipid levels, inflammatory markers, body composition, and HIV control were measured.

RESULTS

Compared with placebo, r-metHuLeptin therapy improved fasting insulin levels, insulin resistance (as expressed by the homeostasis model assessment index and an insulin suppression test), and high-density lipoprotein. Body weight and fat mass decreased on r-metHuLeptin, mainly due to a decrease in truncal fat but not peripheral fat or lean body mass. r-metHuLeptin was well tolerated, and HIV control was not adversely affected.

CONCLUSIONS

r-metHuLeptin replacement at physiological doses in HIV+ leptin-deficient patients with HAART-induced lipoatrophy improves insulin resistance, high-density lipoprotein, and truncal fat mass. Future larger and more long-term studies in HAART-induced lipoatrophy, including patients with more severe metabolic abnormalities, are warranted to evaluate the physiological and potentially therapeutic role of r-metHuLeptin for this condition and to fully clarify the underlying mechanisms of action.

Prevalence of the metabolic syndrome among patients receiving clozapine

OBJECTIVE

This study compared the prevalence of the metabolic syndrome among outpatients with schizophrenia and schizoaffective disorder receiving clozapine with a matched comparison group from the National Health and Nutrition Examination Survey.

METHOD

Ninety-three outpatients and a matched group of 2,701 comparison subjects were compared according to National Cholesterol Education Program criteria. Outpatient data were obtained through physical assessments, laboratory testing, and reviews of medical records.

RESULTS

The prevalence of the metabolic syndrome was significantly higher among clozapine patients (53.8%) than among the comparison group (20.7%). For clozapine patients, logistic regression analysis revealed significant associations with age, body mass index, and duration of clozapine treatment. Only age and body mass index were associated with the prevalence of metabolic syndrome in both groups.

CONCLUSIONS

Patients receiving clozapine are at significantly increased risk for developing the metabolic syndrome. Psychiatrists and other providers should consider performing regular physical health monitoring to prevent long-term adverse health consequences.

Metabolic findings from the CATIE trial and their relation to tolerability

The overall effectiveness of antipsychotics for the management of schizophrenia is restricted by their side-effect profiles, particularly over an extended treatment period. Intolerable side effects can reduce patient adherence to medication and often lead to treatment discontinuation. Some side effects that result from antipsychotic use are precursors to the metabolic syndrome, which is prevalent among individuals with schizophrenia and represents a significant source of cardiovascular risk. The Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) schizophrenia study assessed the efficacy of the atypical antipsychotics olanzapine, quetiapine, risperidone, and ziprasidone relative to the conventional drug perphenazine. Additional assessments included the metabolic effects of these agents in patients with schizophrenia and the incidence of negative side effects. No significant differences were found between treatment groups for time to discontinuation due to intolerability, but the rates of side effects significantly differed (P=.04). For metabolic parameters, olanzapine was associated with greater and significant adverse effects on weight, lipids, and glucose metabolism versus the other antipsychotics tested. The CATIE results show that important distinctions exist among currently available atypical antipsychotics. Physicians should be aware of the propensity of these drugs to increase the risks of cardiovascular disease and diabetes in treated patients and tailor individual treatment decisions accordingly. This article highlights the metabolic findings from the CATIE schizophrenia study, and explores the differences shown by atypical antipsychotics, with regard to metabolic side effects that increase cardiovascular risk.

Associations between bipolar disorder and metabolic syndrome: A review

OBJECTIVES

To examine the pathophysiologic mechanisms that may link bipolar disorder and metabolic syndrome and to discuss whether the consequences of metabolic syndrome underlie a substantive portion of the premature morbidity and mortality observed in persons with bipolar disorder.

DATA SOURCES

A MEDLINE search, citing articles from 1966 onward, supplemented by a review of bibliographies, was conducted to identify relevant studies. Bipolar disorder, mood disorder, metabolic syndrome, diabetes, cardiovascular illness, and obesity were used as keywords. Criteria used to select studies included (1) English language, (2) published studies with original data in peer-reviewed journals, and (3) studies that confirmed the nature of the mood disorder examined.

RESULTS

Ninety-seven studies met criteria and were reviewed for evidence of dysregulation in various physiologic systems. Bipolar disorder and metabolic syndrome share features of hormonal, immunologic, and autonomic nervous system dysregulation.

CONCLUSION

Lifestyle features may account, in part, for the premature mortality observed in bipolar disorder, but the somatic correlates of the illness may also predispose patients to metabolic syndrome and the consequent increased risk of diseases such as diabetes and vascular disease.

Highly Active Antiretroviral Therapy-Associated Metabolic Syndrome and Cardiovascular Risk

The introduction of highly active antiretroviral therapy (HAART) has significantly modified the course of human immunodeficiency virus (HIV) disease, with longer survival and improved quality of life of HIV-infected subjects. However, HAART regimens, especially those including protease inhibitors, have been shown to cause in a high proportion of HIV-infected patients a metabolic syndrome (lipodystrophy/lipoatrophy, dyslipidemia, type 2 diabetes mellitus, insulin resistance) that may be associated with an increased risk of cardiovascular disease (coronary artery disease and stroke). A careful stratification of the cardiovascular risk and cardiovascular monitoring of patients under HAART is needed according to the most recent clinical guidelines.

Side effects of atypical antipsychotics: extrapyramidal symptoms and the metabolic syndrome

In this article we examine the two major classes of side effects with atypical antipsychotics: extrapyramidal symptoms (EPS) and the metabolic syndrome (the triad of diabetes, dyslipidemia, and hypertension, with associated obesity). We conclude that atypical antipsychotics continue to have notable risks of EPS, particularly akathisia, and that these agents also appear to increase the risk of the metabolic syndrome, though this effect seems most marked with clozapine and olanzapine. Novel conclusions based on this review are as follows: we provide a classification scheme based on low versus high D2 binding affinity (which is, to our knowledge, a new means of classifying atypical antipsychotics); we emphasize that the akathisia risk is likely equal among agents and that tardive dyskinesia is an early, and not late, risk in treatment (a common misconception); we make the methodological point that in randomized clinical trials, there is a high risk of false-negatives regarding side effects; we raise the issue of confounding bias in epidemiological studies of metabolic syndrome; and we stress the need to compare side effects in the same studies and not different studies. Future prospective observational cohort studies must target side effects and be designed to collect and analyze data on confounding factors.

Highly Active Antiretroviral Therapy–Associated Metabolic Syndrome: Pathogenesis and Cardiovascular Risk*

The introduction of highly active antiretroviral therapy (HAART) has significantly modified the course of HIV disease, with longer survival and improved quality of life of HIV-infected subjects. However, HAART regimens, especially those including protease inhibitors (PIs) have been shown to cause in a high proportion of HIV-infected patients a metabolic syndrome that may be associated with an increased risk of cardiovascular disease (about 1.4 cardiac events per 1,000 years of therapy according to the Framingham score). Metabolic features associated with somatic changes (lipodystrophy/lipoatrophy) include dyslipidemia (about 70% of patients), insulin resistance (elevated C-peptide and insulin), type 2 diabetes mellitus (8%-10% of the patients), hypertension (up to 75% of patients), coagulation abnormalities (25% of patients), lactic acidemia, and elevated hepatic transaminases (nonalcoholic steatohepatitis). HAART-associated metabolic syndrome is an increasingly recognized clinical entity. A better understanding of the molecular mechanisms responsible for this syndrome will lead to the discovery of new drugs that will reduce the cardiovascular risk in patients under HAART. A careful stratification of the cardiovascular risk and cardiovascular monitoring of patients under HAART is needed according to the most recent clinical guidelines.

Metabolic syndrome and the risk of coronary heart disease in 367 patients treated with second-generation antipsychotic drugs

OBJECTIVE

To examine the relationship between presence of metabolic syndrome and the risk of coronary heart disease (CHD) events (angina pectoris, myocardial infarction, and sudden cardiac death) in patients treated with second-generation antipsychotic medications.

METHOD

367 adults treated with second-generation antipsychotics randomly selected from consecutive psychiatric admissions to a single hospital between August 1, 2004, and March 1, 2005, underwent assessments evaluating the presence of metabolic syndrome. The 10-year risk of CHD events was calculated according to the Framingham scoring system for age, smoking, total cholesterol, high-density lipoprotein (HDL)-cholesterol, blood pressure, and history of diabetes and was compared in patients with and without the metabolic syndrome.

RESULTS

Metabolic syndrome, present in 137 patients (37.3%), was associated with a significantly greater age- and race-adjusted 10-year risk of CHD events, i.e., 11.5% vs. 5.3% for men (risk ratio = 2.18, 95% CI = 1.88 to 2.48, p < .0001) and 4.5% vs. 2.3% for women (risk ratio = 1.94, 95% CI = 1.65 to 2.23, p = .0005). The increased risk of CHD events in patients with metabolic syndrome remained significant after the exclusion of diabetic patients. In a logistic regression analysis of variables independent of the Framingham scoring system, triglyceride levels (p < .0001), waist circumference (p = .035), and white race (p = .047) were significantly associated with the 10-year risk of CHD events (R2 = 0.134; p < .0001).

CONCLUSIONS

These data confirm the high prevalence of metabolic syndrome in patients receiving second-generation anti-psychotics, indicate that metabolic syndrome doubles the 10-year risk of CHD events in this population, and emphasize the importance of the "hypertriglyceridemic waist" for the identification of psychiatric patients at high risk of CHD.

Metabonomic study on the biochemical profiles of a hydrocortisone-induced animal model

This work describes the metabonomic study of a biochemical modification in vivo induced by high dose of hydrocortisone, which led to a unique pathologic condition similar to the 'kidney deficiency syndromes', an early stage of obesity and diabetes in traditional Chinese medicine. The methodology of the metabonomic approach consisted of GC/MS and multivariate statistical technique for the establishment of urine metabolic patterns of the treatment rats. In the study, 24-h urine was collected pre-dose and at days 1, 3, 7, and 10 post-dose after rats were injected with hydrocortisone at 1.5 mg/100 g. The acquired data were transferred into Matlab to be processed using principal components analysis (PCA). The results indicated that clear and consistent biochemical changes following hydrocortisone intervention under controlled conditions could be identified using chemometric analysis. The work suggests that this metabonomic approach could be used as a potentially powerful tool to investigate the biochemical changes of certain physiopathologic conditions such as metabolic syndrome, as an early diagnostic means.

Prevalence of the metabolic syndrome in veterans with schizophrenia

The metabolic syndrome has become a focus of clinical attention due to its high prevalence in the United States (23%) and impact on cardiovascular risk, yet limited data exist on the prevalence of this syndrome among U.S. veterans with schizophrenia.

METHODS

A convenience sample of patients diagnosed with schizophrenia or schizoaffective disorder was obtained from inpatient units and outpatient clinics at Veterans Affairs medical centers in San Diego and Los Angeles.

RESULTS

In this predominantly male (92.5%) sample of 80 veterans, with mean age of 49.0 years, the age-adjusted prevalence of the metabolic syndrome was 51.2%, more than twice the age-adjusted prevalence in the general U.S. population. The female cohort was small (n = 6), but had a greater mean body mass index and higher prevalence of metabolic syndrome than the male subjects.

CONCLUSIONS

The metabolic syndrome is highly prevalent in this sample of patients with schizophrenia and represents an enormous source of cardiovascular disease risk. Clinicians who treat patients with schizophrenia should monitor for the parameters that define the metabolic syndrome as part of the ongoing management of patients treated with antipsychotics.

Recognizing and monitoring adverse events of second-generation antipsychotics in children and adolescents

Although second-generation antipsychotics (SGAs) are used increasingly in children and adolescents, data on the effectiveness and safety in pediatric populations are still sparse. Much of the safety information is derived from studies conducted in adults. This derivation is problematic because children and adolescents are exposed to SGAs during a phase of unparalleled physical and psychologic development that can affect pharmacokinetic and pharmacodynamic drug actions, efficacy, and side-effect patterns. This article presents an overview of SGA-related side effects in children and adolescents and strategies to monitor health outcomes effectively in youngsters receiving SGAs.

Abstinence, anticipation, reduction, and treatment (AART): a stepwise approach to the management of atypical antipsychotic side effects

Antipsychotic medications, specifically the atypical agents, serve as first-line treatment options for patients with psychotic disorders, including individuals with schizophrenia or schizoaffective disorder. Atypical antipsychotics are also often prescribed off-label as either the primary treatment or as an adjunctive treatment for individuals with other disorders, including mood disorders without psychosis, behavioral disorders, and insomnia. Despite the generally superior side-effect profiles of atypical antipsychotics compared with typical antipsychotic agents, the atypicals have been associated with a number of serious side effects, including metabolic disorders, cardiovascular disorders, seizures, hyperprolactinemia, and movement disorders. This article offers a stepwise approach to the management of antipsychotic side effects: Abstinence, Anticipation, Reduction, and Treatment (AART). The steps in AART are hierarchical, but often overlap in the areas of risk prevention and minimization. The authors discuss issues relevant to each level of intervention and provide suggestions for integrating the AART approach into a comprehensive treatment plan. By incorporating this stepwise approach into their clinical decision-making process, prescribers may be able to optimize the risk:benefit ratio associated with the prescription of atypical antipsychotics.

Insulin resistance in the HIV-infected population: the potential role of mitochondrial dysfunction

Insulin resistance is accepted as the underlying fundamental defect that predates and ultimately leads to the development of type 2 (adult onset) diabetes mellitus in the general non-human immunodeficiency virus (HIV)-infected population. Insulin resistance is also a major component of the metabolic syndrome that, in association with other factors such as hypertension, hypercholesterolemia, and central obesity, defines a pre-diabetic atherogenic state that leads to adverse cardiovascular events. Growing evidence now suggests that mitochondrial dysfunction in skeletal muscle may be the mechanism whereby insulin resistance is induced. The prevalence of insulin resistance, glucose intolerance, and diabetes in the HIV-infected population has dramatically increased following the common use of highly active antiretroviral therapy (HAART). The development of insulin resistance in the HIV-infected population is likely to be multifactorial reflecting genetic predisposition, direct and indirect effects of both the protease inhibitor (PI) and nucleoside reverse transcriptase inhibitor (NRTI) class of antiretroviral therapy, and a possible contribution from chronic inflammatory changes induced by HIV. Indirect effects of antiretroviral therapy on insulin resistance may be mediated through both the visceral adiposity and peripheral fat depletion components of lipodystrophy as well as through fatty infiltration in liver and muscle. Based on current knowledge, mitochondrial dysfunction can be hypothesized to play a key role in each of these components.

A causal role for uric acid in fructose-induced metabolic syndrome

The worldwide epidemic of metabolic syndrome correlates with an elevation in serum uric acid as well as a marked increase in total fructose intake (in the form of table sugar and high-fructose corn syrup). Fructose raises uric acid, and the latter inhibits nitric oxide bioavailability. Because insulin requires nitric oxide to stimulate glucose uptake, we hypothesized that fructose-induced hyperuricemia may have a pathogenic role in metabolic syndrome. Four sets of experiments were performed. First, pair-feeding studies showed that fructose, and not dextrose, induced features (hyperinsulinemia, hypertriglyceridemia, and hyperuricemia) of metabolic syndrome. Second, in rats receiving a high-fructose diet, the lowering of uric acid with either allopurinol (a xanthine oxidase inhibitor) or benzbromarone (a uricosuric agent) was able to prevent or reverse features of metabolic syndrome. In particular, the administration of allopurinol prophylactically prevented fructose-induced hyperinsulinemia (272.3 vs.160.8 pmol/l, P < 0.05), systolic hypertension (142 vs. 133 mmHg, P < 0.05), hypertriglyceridemia (233.7 vs. 65.4 mg/dl, P < 0.01), and weight gain (455 vs. 425 g, P < 0.05) at 8 wk. Neither allopurinol nor benzbromarone affected dietary intake of control diet in rats. Finally, uric acid dose dependently inhibited endothelial function as manifested by a reduced vasodilatory response of aortic artery rings to acetylcholine. These data provide the first evidence that uric acid may be a cause of metabolic syndrome, possibly due to its ability to inhibit endothelial function. Fructose may have a major role in the epidemic of metabolic syndrome and obesity due to its ability to raise uric acid.

Ritonavir-boosted protease inhibitors, Part 2: cardiac implications of lipid alterations

Ritonavir-boosted protease inhibitor (PI) regimens have provided substantial benefits in the treatment of HIV/AIDS, resulting in improved clinical outcomes. However, treatment toxicities often affect adherence and may influence outcomes. Dyslipidemia is highly prevalent in many patients who receive a boosted PI regimen. The mechanism underlying dyslipidemia is probably multifactorial and may differ among the individual PIs. The prevalence of cardiovascular disease and events appears to be higher in patients treated with boosted PIs, and as long-term survival increases in HIV-infected persons, the long-term effect of dyslipidemia becomes a growing concern. The practitioner must consider the possibility of these adverse effects when choosing the antiretroviral regimen that best suits each patient. Until future studies define the optimal approach, an evaluation of cardiovascular risk factors and treatment of those risk factors according to evidence-based guidelines are warranted.

Clozapine, diabetes mellitus, hyperlipidemia, and cardiovascular risks and mortality: results of a 10-year naturalistic study

OBJECTIVE

The goal of this 10-year naturalistic study was to examine, in clozapine-treated patients, the change in cardiovascular risk factors following clozapine initiation and the mortality estimates from cardiovascular disease.

METHOD

Data were collected from medical records from January 1992 to December 2003 and included age, gender, race, diagnosis, family history of diabetes, and age at clozapine initiation for clozapine-treated patients with schizophrenia or schizoaffective disorder (DSM-IV criteria). Clozapine dosage and laboratory results were recorded at 12-month intervals.

RESULTS

At the time of clozapine initiation, the mean +/-?SD age of the 96 patients studied was 36.5 +/- 7.9 years; 28% (N = 27) were women. The Kaplan-Meier estimate for 10-year mortality from cardiovascular disease was 9%. African American and Hispanic American patients exhibited elevated risk of cardiovascular disease-related mortality (odds ratio [OR] = 7.2, p = .09; OR = 11.3, p = .04, respectively) compared to white patients. Body mass index (BMI) significantly increased the odds ratio of mortality (OR = 1.2, p < .01). The Kaplan-Meier estimate for new-onset diabetes mellitus was approximately 43%, and Hispanic American (OR = 4.3, p = .027) and African American (OR = 11.5, p = .0001) patients showed elevated risks of developing diabetes mellitus compared to white patients. Additionally, BMI (OR = 1.11, p = .0006), total cholesterol level (OR = 1.006, p = .04), and serum triglyceride level (OR = 1.002, p = .04) modestly increased the odds ratio for the development of diabetes mellitus.

CONCLUSIONS

These results support the hypothesis that clozapine-treated patients appear to be at risk for death from cardiovascular disease secondary to clozapine-associated medical disorders such as obesity, diabetes, hypertension, and hyperlipidemia.

[Possible connection between ghrelin, resistin and TNF-alpha levels and the metabolic syndrome caused by atypical antipsychotics]

Second generation antipsychotics (SGA) are obesitogenic and diabetogenic. Role of ghrelin (RIA), resistin and TNF-alpha (ELISA) in weight gain and insulin resistance (fasting plasma insulin, HOMA, ELISA) was studied in Hungarian psychiatryic patients (n=60) treated with SGA (clozapine, olanzapine, risperidone, quetiapine, 15 each). After 1 year, 80% of patients became overweight/obese (BMI > 27/30) and 35% (n= 21/60) presented impaired glucose tolerance (13/60) or diabetes (8/60). Ghrelin (1.3 +/- 0.6 ng/ml), resistin (9.8 +/- 3.7 ng/ml), TNF-alpha (5.8 +/- 1.7 pg/ml), insulin (10.4 +/- 7.6 U/ml, HOMA A: 2.5 +/- 1.8, HOMA B: 133 +/- 62.5) were significantly higher in patients than in healthy matched controls. Resistin and TNF-alpha positively correlated with each other, insulin, HOMA, and negatively with ghrelin. Ghrelin contributes to weight gain, resistin and TNF-alpha to insulin resistance. A negative feedback regulation may exist between adipocytokines and ghrelin production. SGA drugs enhance ghrelin production despite the suppressive effect of adipocytokines. All four SGA drugs are equally obesitogenic and diabetogenic.

Circulating resistin levels are not associated with fat redistribution, insulin resistance, or metabolic profile in patients with the highly active antiretroviral therapy-induced metabolic syndrome

CONTEXT

The mechanisms underlying the development of the highly active antiretroviral therapy (HAART)-induced metabolic syndrome remain to be fully elucidated.

OBJECTIVE

The objective of this study was to investigate whether the adipocyte-secreted hormone, resistin, is associated with anthropometric and metabolic abnormalities of the HAART-induced metabolic syndrome.

DESIGN, SETTING, AND PATIENTS

We conducted a cross-sectional study of 227 HIV-positive patients (37 women and 190 men) recruited from the infectious diseases clinics. On the basis of history, physical examination, dual-energy x-ray absorptiometry, and single-slice computed tomography, patients were classified into four groups: non-fat redistribution (n = 85), fat accumulation (n = 42), fat wasting (n = 35), and mixed fat redistribution (n = 56).

MAIN OUTCOME MEASURES

The main outcome measures were serum resistin levels and anthropometric and metabolic variables.

RESULTS

Mean serum resistin levels were not significantly different among subjects with fat accumulation, fat wasting, or mixed fat redistribution or between these groups and the non-fat redistribution group. We found a weak, but significant, positive correlation between resistin and percent total body fat (r = 0.20; P < 0.01), total extremity fat (r = 0.18; P < 0.01), and abdominal sc fat (r = 0.19; P < 0.01), but not abdominal visceral fat (r = -0.10; P = 0.16) or waist to hip ratio (r = -0.05; P = 0.43). When adjustments were made for gender (women, 3.92 +/- 2.71 ng/ml; men, 2.96 +/- 2.61 ng/ml; P = 0.05), correlations between resistin and the above parameters were no longer significant. Importantly, resistin levels were not correlated with fasting glucose, insulin, homeostasis model assessment of insulin resistance index, triglycerides, or cholesterol levels in the whole group.

CONCLUSIONS

Resistin is related to gender, but is unlikely to play a major role in the insulin resistance and metabolic abnormalities of the HAART-induced metabolic syndrome.