Chitin-glucan fiber effects on oxidized low-density lipoprotein: a randomized controlled trial.

BACKGROUND/OBJECTIVES: Elevated oxidized low-density lipoprotein (OxLDL) may promote inflammation, and is associated with increased risk of atherosclerotic coronary heart disease and worsening complications of diabetes mellitus. The primary objective of this study was to evaluate the efficacy of chitin-glucan (CG), alone and in combination with a potentially anti-inflammatory olive oil (OO) extract, for reducing OxLDL in subjects with borderline to high LDL cholesterol (LDL-C) levels. SUBJECTS/METHODS: This 6-week, randomized, double-blind, placebo-controlled study of a novel, insoluble fiber derived from the Aspergillus niger mycelium, CG, evaluated 130 subjects free of diabetes mellitus with fasting LDL-C 3.37-4.92 mmol/l and glucose ≤ 6.94 mmol/l. Participants were randomly assigned to receive CG (4.5 g/day; n=33), CG (1.5 g/day; n=32), CG (1.5 g/day) plus OO extract (135 mg/day; n=30), or matching placebo (n=35). RESULTS: Administration of 4.5 g/day CG for 6 weeks significantly reduced OxLDL compared with placebo (P=0.035). At the end of study, CG was associated with lower LDL-C levels relative to placebo, although this difference was statistically significant only for the CG 1.5 g/day group (P=0.019). CG did not significantly affect high-density lipoprotein cholesterol, triglycerides, glucose, insulin or F2-isoprostane levels. Adverse events did not substantively differ between treatments and placebo. CONCLUSIONS: In this 6-week study, CG (4.5 g/day) reduced OxLDL, an effect that might affect the risk for atherosclerosis.

Rate and risk predictors for development of self-reported type-2 diabetes mellitus over a 5-year period: the SHIELD study.

AIMS: This investigation determined the proportion of adults newly diagnosed as having type-2 diabetes mellitus (T2DM), and ascertained risk predictors for development of self-reported T2DM. METHODS: The US Study to Help Improve Early evaluation and management of risk factors Leading to Diabetes (SHIELD) survey was a 5-year longitudinal study of adults with and without diabetes mellitus. Adults completed a baseline health questionnaire in 2004 and ≥1 annual follow-up survey through 2009. Respondents with no self-reported diagnosis of diabetes at baseline were followed to measure rate of and assess risk factors for development of T2DM over 5 years. RESULTS: Among 8582 respondents without diabetes at baseline, 622 (7.2%) reported a diagnosis of T2DM over the subsequent 5 years. Increasing age, family history of T2DM, body mass index ≥30 kg/m(2), abdominal obesity, excessive thirst, asthma, gestational diabetes and 'high blood sugar without diabetes' significantly increased the risk of developing T2DM (p < 0.05 for each). Good to excellent health status and self-reported circulatory problems decreased the risk (p < 0.05 for each). CONCLUSIONS: Among this representative US adult population, the rate of developing T2DM was 7.2% over 5 years. Predictors of T2DM diagnosis identified in this analysis were readily obtainable via self-report.

Phentermine/topiramate for weight reduction and treatment of adverse metabolic consequences in obesity.

Phentermine hydrochloride is a noradrenergic sympathetic amine approved for decades by the U.S. Food and Drug Administration (FDA) at doses as high as 37.5 mg/day for the short-term treatment of obesity. Topiramate is a sulfamate-substituted monosaccharide marketed since 1996, and approved by the FDA for seizure disorders at doses up to 400 mg/day and for the prevention of migraine headaches at doses up to 100 mg/day. Clinical trial data suggest topiramate promotes weight loss. The prescribing information of neither agent describes adverse drug interactions with the other. The controlled-release formulation of phentermine and topiramate at low, medium and full doses (with full dose containing 15 mg of phentermine hydrochloride and 92 mg of topiramate) promotes weight reduction, with clinical trial data supporting improvement in adiposopathic consequences leading to metabolic diseases. Reported adverse events with this combination agent are as expected, based upon knowledge of the individual components.

The Bile Acid Sequestrant Acceptability scale validation study.

AIMS: The primary objective of this study was to validate a novel Bile Acid Sequestrant Acceptability (BASA) Scale intended to assess the acceptability and/or tolerability of bile acid sequestrant (BAS) beverage preparations. A secondary objective was to assess the utility of weightings based on subjective clinical importance for the BASA scale individual components and its composite score. METHODS: This was a randomised, single-blind, single site, controlled study of oral administration of 4 g of orange-flavoured generic cholestyramine powder, 12 g of orange-flavoured generic cholestyramine powder and an orange-flavoured sweetened control drink powder, each mixed with water. RESULTS: The study sample included 42 subjects; 26 men and 16 women. Participants were non-Hispanic white (76.2%) or black/African American (23.8%), with a mean age of 51.4 years and body mass index of 30.1 kg/m(2). The components of the BASA scale were taste, texture, appearance and mixability; the possible total BASA scores ranged being 4-20; the higher the BASA scale score, the better the acceptability/tolerability. Composite BASA scale scores were significantly lower for the 4 g (mean BASA score = 10.3) and 12 g (mean BASA score = 9.4) cholestyramine compared with the control drink powder (mean BASA score = 16.7) (p < 0.001). BASA scale scores did not significantly differ between the 4 and 12 g of cholestyramine. (p = 0.215). Weighting of the components did not materially alter the results. Findings for the individual components of the BASA scale were similar to the composite values. CONCLUSION: The BASA scale effectively distinguished between an orange-flavoured BAS powder and a commercial orange-flavour control powder.

Adiposopathy and bariatric surgery: is 'sick fat' a surgical disease?

OBJECTIVE: To review how bariatric surgery in obese patients may effectively treat adiposopathy (pathogenic adipose tissue or 'sick fat'), and to provide clinicians a rationale as to why bariatric surgery is a potential treatment option for overweight patients with type 2 diabetes, hypertension, and dyslipidaemia. METHODS: A group of clinicians, researchers, and surgeons, all with a background in treating obesity and the adverse metabolic consequences of excessive body fat, reviewed the medical literature regarding the improvement in metabolic disease with bariatric surgery. RESULTS: Bariatric surgery improves metabolic disease through multiple, likely interrelated mechanisms including: (i) initial acute fasting and diminished caloric intake inherent with many gastrointestinal surgical procedures; (ii) favourable alterations in gastrointestinal endocrine and immune responses, especially with bariatric surgeries that reroute nutrient gastrointestinal delivery such as gastric bypass procedures; and (iii) a decrease in adipose tissue mass. Regarding adipose tissue mass, during positive caloric balance, impaired adipogenesis (resulting in limitations in adipocyte number or size) and visceral adiposity are anatomic manifestations of pathogenic adipose tissue (adiposopathy). This may cause adverse adipose tissue endocrine and immune responses that lead to metabolic disease. A decrease in adipocyte size and decrease in visceral adiposity, as often occurs with bariatric surgery, may effectively improve adiposopathy, and thus effectively treat metabolic disease. It is the relationship between bariatric surgery and its effects upon pathogenic adipose tissue that is the focus of this discussion. CONCLUSIONS: In selective obese patients with metabolic disease who are refractory to medical management, adiposopathy is a surgical disease.

Does nicotinic acid (niacin) lower blood pressure?

Nicotinic acid (niacin) is a well-established treatment for dyslipidaemia - an important cardiovascular disease (CVD) risk factor. However, niacin may also reduce blood pressure (BP), which is another important CVD risk factor. This review examines the limited publicly available data on niacin's BP effects. Acute administration of immediate-release niacin may lower BP because of niacin's acute vasodilatory effects. Although not always supported by clinical trial data, the package insert of a prescription, extended-release niacin describes niacin-induced acute hypotension. From a chronic standpoint, larger studies, such as the Coronary Drug Project, suggest that niacin may lower BP when administered over a longer period of time. Post hoc analyses of some of the more recent niacin clinical trials also support a more chronic, dose-dependent, BP-lowering effect of niacin. Because laropiprant [a prostaglandin D(2) (PGD(2)) type 1 (DP1) receptor antagonist] does not attenuate niacin's BP-lowering effects, it is unlikely that any chronic lowering of BP by niacin is due to dilation of dermal vessels through activation of the DP1 receptor by PGD(2.) Further research is warranted to evaluate the extent and mechanisms of niacin's effects on BP.

Is adiposopathy (sick fat) an endocrine disease?

OBJECTIVE: To review current consensus and controversy regarding whether obesity is a 'disease', examine the pathogenic potential of adipose tissue to promote metabolic disease and explore the merits of 'adiposopathy' and 'sick fat' as scientifically and clinically useful terms in defining when excessive body fat may represent a 'disease'. METHODS: A group of clinicians and researchers, all with a background in endocrinology, assembled to evaluate the medical literature, as it pertains to the pathologic and pathogenic potential of adipose tissue, with an emphasis on metabolic diseases that are often promoted by excessive body weight. RESULTS: The data support pathogenic adipose tissue as a disease. Challenges exist to convince many clinicians, patients, healthcare entities and the public that excessive body fat is often no less a 'disease' than the pathophysiological consequences related to anatomical abnormalities of other body tissues. 'Adiposopathy' has the potential to scientifically define adipose tissue anatomic and physiologic abnormalities, and their adverse consequences to patient health. Adiposopathy acknowledges that when positive caloric balance leads to adipocyte hypertrophy and visceral adiposity, then this may lead to pathogenic adipose tissue metabolic and immune responses that promote metabolic disease. From a patient perspective, explaining how excessive caloric intake might cause fat to become 'sick' also helps provide a rationale for patients to avoid weight gain. Adiposopathy also better justifies recommendations of weight loss as an effective therapeutic modality to improve metabolic disease in overweight and obese patients. CONCLUSION: Adiposopathy (sick fat) is an endocrine disease.

Measuring flushing symptoms with extended-release niacin using the flushing symptom questionnaire: results from a randomised placebo-controlled clinical trial.

INTRODUCTION: Niacin is underutilised because of flushing. Lack of a quantitative tool to assess niacin-induced flushing has precluded the objective evaluation of flushing associated with extended-release (ER) niacin formulations. We developed the Flushing Symptom Questionnaire((c)) (FSQ), a quantitative tool to assess patient-reported flushing, and assessed its ability to characterise ER niacin-induced flushing. METHODS: This study focused on the responses to one question in the FSQ, the Global Flushing Severity Score (GFSS), reported on a 0-10 scale (none = 0, mild = 1-3, moderate = 4-6, severe = 7-9 and extreme = 10) to assess flushing during ER niacin initiation (week 1) and maintenance (weeks 2-8). RESULTS: Flushing severity with ER niacin was greatest during week 1 and remained greater than placebo for the study duration. During weeks 2-8, 40% of patients on ER niacin vs. 8% of those on placebo had > 1 day/week with 'moderate or greater' GFSS. CONCLUSIONS: In conclusion, the GFSS component of the FSQ was a sensitive and responsive quantitative measure of ER niacin-induced flushing that will aid in the objective comparison of novel strategies intended to improve tolerability and adherence to niacin, an agent proven to reduce cardiovascular risk.

Lipid-modifying efficacy and tolerability of extended-release niacin/laropiprant in patients with primary hypercholesterolaemia or mixed dyslipidaemia.

BACKGROUND: Improving lipids beyond low-density lipoprotein cholesterol (LDL-C) lowering with statin monotherapy may further reduce cardiovascular risk. Niacin has complementary lipid-modifying efficacy to statins and cardiovascular benefit, but is underutilised because of flushing, mediated primarily by prostaglandin D(2) (PGD(2)). Laropiprant (LRPT), a PGD(2) receptor (DP1) antagonist that reduces niacin-induced flushing has been combined with extended-release niacin (ERN) into a fixed-dose tablet. METHODS AND RESULTS: Dyslipidaemic patients were randomised to ERN/LRPT 1 g (n = 800), ERN 1 g (n = 543) or placebo (n = 270) for 4 weeks. Doses were doubled (2 tablets/day; i.e. 2 g for active treatments) for 20 weeks. ERN/LRPT 2 g produced significant changes vs. placebo in LDL-C (-18.4%), high-density lipoprotein cholesterol (HDL-C; 20.0%), LDL-C:HDL-C (-31.2%), non-HDL-C (-19.8%), triglycerides (TG; -25.8%), apolipoprotein (Apo) B (-18.8%), Apo A-I (6.9%), total cholesterol (TC; -8.5%), TC:HDL-C (-23.1%) and lipoprotein(a) (-20.8%) across weeks 12-24. ERN/LRPT produced significantly less flushing than ERN during initiation (week 1) and maintenance (weeks 2-24) for all prespecified flushing end-points (incidence, intensity and discontinuation because of flushing). Except for flushing, ERN/LRPT had a safety/tolerability profile comparable with ERN. CONCLUSION: Extended-release niacin/LRPT 2 g produced significant, durable improvements in multiple lipid/lipoprotein parameters. The improved tolerability of ERN/LRPT supports a simplified 1 g-->2 g dosing regimen of niacin, a therapy proven to reduce cardiovascular risk.

The relationship of body mass index to diabetes mellitus, hypertension and dyslipidaemia: comparison of data from two national surveys.

The objectives of this study were to explore the relation between body mass index (BMI) and prevalence of diabetes mellitus, hypertension and dyslipidaemia; examine BMI distributions among patients with these conditions; and compare results from two national surveys. The Study to Help Improve Early evaluation and management of risk factors Leading to Diabetes (SHIELD) 2004 screening questionnaire (mailed survey) and the National Health and Nutrition Examination Surveys (NHANES) 1999-2002 (interview, clinical and laboratory data) were conducted in nationally representative samples>or=18 years old. Responses were received from 127,420 of 200,000 households (64%, representing 211,097 adults) for SHIELD, and 4257 participants for NHANES. Prevalence of diabetes mellitus, hypertension and dyslipidaemia was estimated within BMI categories, as was distribution of BMI levels among individuals with these diseases. Mean BMI was 27.8 kg/m2 for SHIELD and 27.9 kg/m2 for NHANES. Increased BMI was associated with increased prevalence of diabetes mellitus, hypertension and dyslipidaemia in both studies (p<0.001). For each condition, approximately [corrected] 75% or more [corrected] of patients had BMI>or=25 kg/m2. Estimated prevalence of diabetes mellitus and hypertension was similar in both studies, while dyslipidaemia was substantially higher in NHANES than SHIELD. In both studies, prevalence of diabetes mellitus, hypertension and dyslipidaemia occurred across all ranges of BMI, but increased with higher BMI. However, not all overweight or obese patients had these metabolic diseases and not all with these conditions were overweight or obese. Except for dyslipidaemia prevalence, SHIELD was comparable with NHANES. Consumer panel surveys may be an alternative method to collect data on the relationship of BMI and metabolic diseases.

Effectiveness and tolerability of ezetimibe in patients with primary hypercholesterolemia: pooled analysis of two phase II studies.

BACKGROUND: Ezetimibe (SCH 58235) is a novel cholesterol absorption inhibitor that selectively and potently blocks intestinal absorption of dietary and biliary cholesterol. OBJECTIVE: Data from 2 multicenter, placebo-controlled, double-blind, randomized, parallel-group, 12-week studies of ezetimibe were pooled to evaluate the drug's effect on lipid parameters in patients with primary hypercholesterolemia. METHODS: After dietary stabilization (National Cholesterol Education Program Step I diet or a stricter diet), washout of lipid-altering drugs, and a 6-week placebo lead-in period, patients with baseline plasma low-density lipoprotein cholesterol (LDL-C) levels > or = 130 and < or = 250 mg/dL and plasma triglyceride (TG) levels < or = 300 mg/dL were randomized to receive either ezetimibe 0.25, 1, 5, or 10 mg, or placebo administered once daily before the morning meal in study A (dose-response study) or ezetimibe 5 or 10 mg or placebo administered once daily before the morning meal or at bedtime in study B (dose-regimen study). RESULTS: A total of 432 patients were included in this pooled analysis, 243 in study A and 189 in study B. The 5- and 10-mg doses of ezetimibe significantly reduced LDL-C levels by 15.7% and 18.5%, respectively (P < 0.01 vs placebo) and significantly increased high-density lipoprotein cholesterol (hDL-C) levels by 2.9% and 3.5%, respectively (P < 0.05 vs placebo). A reduction in plasma TG levels was observed (P = NS). With the 10-mg dose of ezetimibe, 67.8% of patients achieved > or = 15% reduction in plasma LDL-C levels, and 22.0% achieved > or = 25% reduction. With the 5-mg dose, 54.0% of patients achieved > or = 15% reduction in plasma LDL-C levels, and 15.3% achieved > or = 25% reduction. The decrease in plasma LDL-C levels was significantly greater with ezetimibe 10 mg compared with ezetimibe 5 mg (P < 0.05). Ezetimibe was well tolerated, with an adverse event profile similar to that of placebo. CONCLUSIONS: In these two 12-week studies, ezetimibe significantly decreased plasma LDL-C levels and increased plasma HDL-C levels, with a tolerability profile similar to that of placebo.

Lipid-altering drugs in development.

Although currently available lipid lowering therapies are effective and well tolerated, the search continues for additional treatments with even better efficacy and tolerability profiles. As well as refinements to existing strategies (new HMG-CoA reductase inhibitors, fibrates and combination therapies) new avenues are being explored. These include inhibitors of enzymes other than HMG-CoA reductase involved in cholesterol regulation and drugs which affect absorption of lipids from the gastrointestinal tract. In the case of the latter, it has been shown that the new antiobesity treatment orlistat can favourably affect the blood lipid profile. In line with an increasing emphasis on improving high density lipoprotein-cholesterol (HDL-C) levels, the potential therapeutic roles of niacin and drugs which inhibit enzymes involved in the metabolism of HDL-C are also being researched.

Drug interactions of lipid-altering drugs.

The use of lipid-altering drugs has been shown to reduce the progression of atherosclerotic lesions and reduce the risk of atherosclerotic events (such as myocardial infarction and stroke). In general, these lipid-altering drugs are well tolerated but there is the potential for drug interactions. For example, HMG-CoA reductase inhibitors may interact with macrolides, azalides, azole antifungals and cyclosporin. Resins (such as cholestyramine and colestipol) may impair the absorption of many concurrent medications. Fibrates have potential drug interactions with warfarin, furosemide (frusemide), oral hypoglycaemics and probenecid. Nicotinic acid (niacin) may have potential drug interactions with high dose aspirin (acetylsalicylic acid), uricosuric agents (such as sulfapyrazone) and alcohol (ethanol). Finally, probucol may have potential drug interactions with antidysrhythmics, tricyclic antidepressants and phenothiazines. In addition, lipid-altering drugs, used in combination, may have the potential for drug interactions, enhancing some of the risks of adverse effects, such as myositis and hepatotoxicity. Therefore, in order to use lipid-altering drugs in the most effective, and safest manner, it is important for the clinician to have an understanding of the mechanisms of potential drug interactions, which drug interactions may theoretically occur, and specifically, which spe cific drug interactions have already been described.

Drug therapy for hyperlipidemia. When reducing cardiovascular risk is a priority.

If you are confused about the plethora of lipid-lowering agents now available and have not been able to read all the latest studies, you are not alone. It is almost impossible for busy physicians to keep up with this rapidly growing area of research. Drs Bays and Dujovne provide an update of the major antihyperlipidemics, along with a discussion of how to select patients for this therapy and the relative cost-effectiveness of the different types of therapy.

Peripheral diabetic neuropathy.

Diabetic neuropathy is a common complication of diabetes mellitus with significant morbidity and mortality. Hyperglycemia with its secondary metabolic, vascular, and enzymatic consequences is most likely to be the predominant cause. The clinical manifestations includes a wide range of somatic and autonomic syndromes. Painful diabetic neuropathy may require symptomatic treatment. The precise role of therapies such as continuous subcutaneous insulin therapy and aldose reductase inhibitors remains to be clarified.