Should we abandon statins in the prevention of bone fractures?

Osteoporosis increases dramatically with age. About 40 % of women in developed countries will experience an osteoporosis-related fracture in the course of their lifetime, with men experiencing approximately one-third to one-half the risk of women. The "lipid hypothesis of osteoporosis" claims for a role of oxidized lipids as a contributing factor in osteoporosis. On the other hand, statins are supposed to exert anabolic effects on the bone, either through their lipid-lowering action or signal pathways that are independent of their effects on lipid levels. The epidemiological evidence seems to suggest that higher triglycerides may give some protection against fracture, although no association with reduced fracture risk has been reported between lipid-lowering drug (except statins) users and non-users. The epidemiological evidence for a role of statins in osteoporosis is strong, with a lower fracture risk ranging from 30 to 40 % in statin users versus non-users. However, some pitfalls inherent to observational studies (high heterogeneity, residual confounding, potential publication bias) and the lack of association in randomized trials suggest caution. At the moment, the evidence for a role of statins in prevention of osteoporosis is insufficient to recommend starting statin therapy with the aim to prevent osteoporosis.

Female sexual dysfunction in women with thyroid disorders

BACKGROUND

Few data exist on the prevalence of female sexual dysfunction (FSD) in thyroid disorders.

AIM

We evaluated FSD in women with thyroid diseases and in control age-matched healthy women to investigate the relationship between sexual function and thyroid hormones.

METHODS

One hundred and four women with thyroid diseases and 53 controls participated in the study. Eighteen with hyperthyroidism (Group 1), 22 hypothyroidism (Group 2), 45 Hashimoto's thyroiditis (Group 3), 19 nodular goiter (Group 4) underwent thyroid function evaluation and sonography. The Female Sexual Function Index (FSFI) assessed sexual function.

RESULTS

The prevalence of FSD was 46.1% in thyroid diseases and 20.7% in controls. Only in Group 4, the prevalence (68.4%) was significantly higher than in controls (p<0.005). The mean total FSFI score was 20.1 ± 7.1 in women with thyroid diseases and 25.6 ± 4.7 in the controls (p<0.001). Compared with controls, there was a significant decrease of desire in Group 2; desire, arousal and lubrication in Group 3; desire, arousal, lubrication, orgasm and satisfaction in Group 4. In thyroid diseases the prevalence of FSD was 53% and 42%, while in the controls was 55% and 20%, in menopausal and pre-menopausal groups, respectively. We found a significant inverse correlation between TSH and FSFI (r=-0.7, p=0.01) in Group 4, which showed the lowest FSFI score (17.8 ± 5.7) and the highest body mass index (28.4 ± 7.1 kg/m(2)).

CONCLUSIONS

Women with thyroid diseases present a higher prevalence of FSD than controls. Although our findings suggest a higher impairment of sexual function in Group 4 and a role for TSH in FSD, further researches are needed.

Total thyroidectomy, without prophylactic central lymph node dissection, in the treatment of differentiated thyroid cancer. Clinical retrospective study on 221 cases

Total thyroidectomy (TT) is the standard of care for differentiated thyroid cancer (DTC), but still there is no consensus about the role of routine use of prophylactic central lymph node dissection. The aim of this study was to analyze our results of TT without prophylactic central lymphadenectomy in the treatment of DTC. Clinical records, between January 1998 and December 2005, of 221 patients undergoing TT, without prophylactic central lymph node dissection, were retrospectively evaluated. Two hundred and eleven patients (95.47 %) also underwent radioiodine (RAI) ablation followed by thyroid stimulating hormone (TSH) suppression therapy. In patients with loco-regional lymph nodal recurrence, lateral and central lymph node dissection was performed. The incidence of permanent hypoparathyroidism (iPTH <10 pg/ml) and permanent vocal fold paralysis were, respectively, 0.91 and 0.91 %. After a 9.6 ± 3.5 years mean follow-up, the rate of loco-regional recurrence, with positive cervical lymph nodes, was 3.16 % (7/221 patients). In these cases a lateral and central lymphadenectomy was carried out without significant complications. Our results showed that TT without prophylactic central lymph node dissection, followed by RAI ablation, was associated with low morbidity and low loco-regional recurrence rate, even if the lack of a control group treated with TT plus prophylactic central lymphadenectomy suggests caution against generalization of our assumption. Such last combined procedure could be indicated in high-risk patients, in whom loco-regional recurrence is more frequent. However, given the trend in the literature toward prophylactic lymphadenectomy and the avoidance of RAI treatment, prospective randomized trials should be conducted to better clarify this issue.

Dipeptidyl peptidase-4 inhibitors in type 2 diabetes therapy--focus on alogliptin

Type 2 diabetes mellitus is a complex and progressive disease that is showing an apparently unstoppable increase worldwide. Although there is general agreement on the first-line use of metformin in most patients with type 2 diabetes, the ideal drug sequence after metformin failure is an area of increasing uncertainty. New treatment strategies target pancreatic islet dysfunction, in particular gut-derived incretin hormones. Inhibition of the enzyme dipeptidyl peptidase-4 (DPP-4) slows degradation of endogenous glucagon-like peptide-1 (GLP-1) and thereby enhances and prolongs the action of the endogenous incretin hormones. The five available DPP-4 inhibitors, also known as 'gliptins' (sitagliptin, vildagliptin, saxagliptin, linagliptin, alogliptin), are small molecules used orally with similar overall clinical efficacy and safety profiles in patients with type 2 diabetes. The main differences between the five gliptins on the market include: potency, target selectivity, oral bioavailability, long or short half-life, high or low binding to plasma proteins, metabolism, presence of active or inactive metabolites, excretion routes, dosage adjustment for renal and liver insufficiency, and potential drug-drug interactions. On average, treatment with gliptins is expected to produce a mean glycated hemoglobin (HbA1c) decrease of 0.5%-0.8%, with about 40% of diabetic subjects at target for the HbA1c goal <7%. There are very few studies comparing DPP-4 inhibitors. Alogliptin as monotherapy or added to metformin, pioglitazone, glibenclamide, voglibose, or insulin therapy significantly improves glycemic control compared with placebo in adult or elderly patients with inadequately controlled type 2 diabetes. In the EXAMINE trial, alogliptin is being compared with placebo on cardiovascular outcomes in approximately 5,400 patients with type 2 diabetes. In clinical studies, DPP-4 inhibitors were generally safe and well tolerated. However, there are limited data on their tolerability, due to their relatively recent marketing approval. Alogliptin will be used most when avoidance of hypoglycemic events is paramount, such as in patients with congestive heart failure, renal failure, and liver disease, and in the elderly.

Mediterranean diet and metabolic syndrome: an updated systematic review

The metabolic syndrome is a health condition characterized by abdominal obesity, dyslipidemia, elevated blood pressure and impaired glucose tolerance, with increasing prevalence. Adherence to the Mediterranean diet seems to exert beneficial effects regarding the metabolic syndrome prevalence and progression. Thus, we performed an updated systematic review of studies which have evaluated the effect of the Mediterranean dietary pattern on the metabolic syndrome. This was a systematic review of epidemiological observational studies and clinical trials. English language publications in the databases PubMed, Embase, Scopus, until May 31, 2013, were included in this review. New evidence from prospective cohort studies, cross-sectional studies and clinical trials supports the beneficial role of adherence to the Mediterranean dietary pattern regarding metabolic syndrome presence and progression. Considering the magnitude of metabolic syndrome, efforts should be made to encourage adoption of this pattern in Mediterranean countries and similar dietary pattern in countries where metabolic syndrome is prevalent.

Glucagon-like peptide 1 reduces endothelial dysfunction, inflammation, and oxidative stress induced by both hyperglycemia and hypoglycemia in type 1 diabetes

OBJECTIVE

Hyperglycemia and hypoglycemia currently are considered risk factors for cardiovascular disease in type 1 diabetes. Both acute hyperglycemia and hypoglycemia induce endothelial dysfunction and inflammation, raising the oxidative stress. Glucagon-like peptide 1 (GLP-1) has antioxidant properties, and evidence suggests that it protects endothelial function.

RESEARCH DESIGN AND METHODS

The effect of both acute hyperglycemia and acute hypoglycemia in type 1 diabetes, with or without the simultaneous infusion of GLP-1, on oxidative stress (plasma nitrotyrosine and plasma 8-iso prostaglandin F2alpha), inflammation (soluble intercellular adhesion molecule-1 and interleukin-6), and endothelial dysfunction has been evaluated.

RESULTS

Both hyperglycemia and hypoglycemia acutely induced oxidative stress, inflammation, and endothelial dysfunction. GLP-1 significantly counterbalanced these effects.

CONCLUSIONS

These results suggest a protective effect of GLP-1 during both hypoglycemia and hyperglycemia in type 1 diabetes.

Fracture risk and bone mineral density in metabolic syndrome: a meta-analysis

BACKGROUND

The risk of bone fractures in subjects with the metabolic syndrome is unknown. We did a meta-analysis to assess the association between metabolic syndrome, risk of fractures, and bone mineral density (BMD).

MATERIALS AND METHODS

We did searches on electronic databases (Medline, Scopus, and ISI Web of Knowledge) until December 2012 and searched reports to identify studies in humans on bone fractures and BMD at different sites. Two independent reviewers collected the relevant reports. We did random-effects meta-analyses to determine the risk of fractures and BMD values associated with metabolic syndrome.

RESULTS

A total of 17 studies, with 35 datasets, were included. In 10 articles (14 datasets) including 1350 incident and 1628 prevalent fractures, metabolic syndrome was associated with a reduced fracture risk (risk ratio = 0.85, 95% confidence interval, 0.71-1.00; high heterogeneity: I(2) = 55%, P = .006). Omission of 2 outlier studies resulted in a significant negative association (risk ratio = 0.85, P = .012; I(2) = 34%, P = .130). Most of the reduced fracture risk was seen in cohort studies (18% reduced risk), suggesting a direction of causality; sex, site of fracture, and definition of the syndrome did not affect the estimates. In 16 articles, including 29 341 subjects, there was no difference in spine, femoral neck, or calcaneus BMD values between subjects with or without metabolic syndrome; mean differences ranged from 0.001 to 0.012 g/cm(2) (P > .10).

CONCLUSIONS

This article shows a reduced risk of bone fractures associated with metabolic syndrome, without modification of BMD. The clinical significance of these findings remains uncertain and should be addressed in future prospective studies.

Management of hyperglycemia in type 2 diabetes: evidence and uncertainty

The panoply of treatment algorithms, periodically released to improve guidance, is one mean to face therapeutic uncertainty in pharmacological management of hyperglycemia in type 2 diabetes, especially after metformin failure. Failure of recent guidelines to give advice on the use of specific antidiabetic drugs in patients with co-morbidity may generate further uncertainty, given the frequent association of type 2 diabetes with common comorbidity, including, although not limited to obesity, cardiovascular disease, impaired renal function, and frailty. The Italian Association of Diabetologists (Associazione Medici Diabetologi, AMD) recognized the need to develop personalized treatment plans for people with type 2 diabetes, taking into account the patients' individual profile (phenotype), with the objective of the safest possible glycemic control. As not every subject with type 2 diabetes benefits from intensive glycemic control, flexible regimens of treatment with diabetes drugs (including insulin) are needed for reaching individualized glycemic goals. Whether personalized diabetology will improve the quality healthcare practice of diabetes management is unknown, but specific research has been launched.

Effect of metabolic syndrome and its components on prostate cancer risk: meta-analysis

BACKGROUND

Literature data examining the role of metabolic syndrome and its components in prostate cancer risk are limited and contradictory.

AIM

We did a meta-analysis of studies that evaluated the association between metabolic syndrome, its components, and risk of prostate cancer.

SUBJECTS AND METHODS

We conducted an electronic search for articles published through September 2012 without restrictions. Every included study was to report risk estimates with 95% confidence intervals for the association between metabolic syndrome and prostate cancer.

RESULTS

The final number of papers included in the meta-analysis was 14, all published in English, with 4728 prostate cancer cases. Metabolic syndrome was associated with a 12% increase in prostate cancer risk (p=0.231), that was lower in cohort studies (7 studies, RR=1.04, p=0.791) than other studies (RR=1.23, p=0.125). The association was significant in the 8 European studies (RR=1.30, p=0.034), but not in the 4 U.S. or 2 Asiatic studies. The risk estimates of prostate cancer for higher values of body mass index, dysglycemia or dyslipidemia (high triglycerides, low HDL-cholesterol) were not significant; on the contrary, hypertension and waist circumference >102 cm were associated with a significant 15% (p=0.035) and 56% (p=0.007) greater risk of prostate cancer, respectively.

CONCLUSIONS

Metabolic syndrome is weakly and non significantly associated with prostate cancer risk, but associations vary with geography. Among single components of the syndrome, hypertension and higher waist circumference are significantly associated with increased risk of prostate cancer.

Basal supplementation of insulin lispro protamine suspension versus insulin glargine and detemir for type 2 diabetes: meta-analysis of randomized controlled trials

OBJECTIVE

We compared the effect of insulin lispro protamine suspension (ILPS) with that of insulin glargine and insulin detemir, all given as basal supplementation, in the treatment of patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We conducted an electronic search until February 2012, including online registries of ongoing trials and abstract books. All randomized controlled trials comparing ILPS with insulin glargine or detemir with a duration of ≥12 weeks were included.

RESULTS

We found four trials lasting 24-36 weeks involving 1,336 persons: three studies compared ILPS with glargine, and one trial compared ILPS with detemir. There was no significant difference in change in HbA(1c) level between ILPS and comparators, in the proportion of patients achieving the HbA(1c) goals of ≤6.5 or <7%, in weight change, or in daily insulin doses. There was no difference in overall hypoglycemia, but nocturnal hypoglycemia occurred significantly more with ILPS than with comparator insulins (mean difference 0.099 events/patient/30 days [95% CI 0.03-0.17]). In a prespecified sensitivity analysis comparing data obtained in patients who remained on their once-daily insulin regimen, not significantly different event rates for nocturnal hypoglycemia were observed between ILPS and comparator insulins (0.063 [-0.007 to 0.13]), and ILPS was associated with lower insulin dose (0.07 units/kg/day [0.05-0.09]).

CONCLUSIONS

There is no difference between ILPS and insulin glargine or detemir for targeting hyperglycemia, but nocturnal hypoglycemia occurred more frequently with ILPS than with comparator insulins. Nocturnal hypoglycemia was not significantly different in people who injected insulin once daily.

Metabolic syndrome and risk of cancer: a systematic review and meta-analysis

OBJECTIVE

Available evidence supports the emerging hypothesis that metabolic syndrome may be associated with the risk of some common cancers. We did a systematic review and meta-analysis to assess the association between metabolic syndrome and risk of cancer at different sites.

RESEARCH DESIGN AND METHODS

We conducted an electronic search for articles published through October 2011 without restrictions and by reviewing reference lists from retrieved articles. Every included study was to report risk estimates with 95% CIs for the association between metabolic syndrome and cancer.

RESULTS

We analyzed 116 datasets from 43 articles, including 38,940 cases of cancer. In cohort studies in men, the presence of metabolic syndrome was associated with liver (relative risk 1.43, P < 0.0001), colorectal (1.25, P < 0.001), and bladder cancer (1.10, P = 0.013). In cohort studies in women, the presence of metabolic syndrome was associated with endometrial (1.61, P = 0.001), pancreatic (1.58, P < 0.0001), breast postmenopausal (1.56, P = 0.017), rectal (1.52, P = 0.005), and colorectal (1.34, P = 0.006) cancers. Associations with metabolic syndrome were stronger in women than in men for pancreatic (P = 0.01) and rectal (P = 0.01) cancers. Associations were different between ethnic groups: we recorded stronger associations in Asia populations for liver cancer (P = 0.002), in European populations for colorectal cancer in women (P = 0.004), and in U.S. populations (whites) for prostate cancer (P = 0.001).

CONCLUSIONS

Metabolic syndrome is associated with increased risk of common cancers; for some cancers, the risk differs betweens sexes, populations, and definitions of metabolic syndrome.

Evidence that hyperglycemia after recovery from hypoglycemia worsens endothelial function and increases oxidative stress and inflammation in healthy control subjects and subjects with type 1 diabetes

Currently there is debate on whether hypoglycemia is an independent risk factor for atherosclerosis, but little attention has been paid to the effects of recovery from hypoglycemia. In normal control individuals and in people with type 1 diabetes, recovery from a 2-h induced hypoglycemia was obtained by reaching normoglycemia or hyperglycemia for another 2 h and then maintaining normal glycemia for the following 6 h. Hyperglycemia after hypoglycemia was also repeated with the concomitant infusion of vitamin C. Recovery with normoglycemia is accompanied by a significant improvement in endothelial dysfunction, oxidative stress, and inflammation, which are affected by hypoglycemia; however, a period of hyperglycemia after hypoglycemia worsens all of these parameters, an effect that persists even after the additional 6 h of normoglycemia. This effect is partially counterbalanced when hyperglycemia after hypoglycemia is accompanied by the simultaneous infusion of vitamin C, suggesting that when hyperglycemia follows hypoglycemia, an ischemia-reperfusion-like effect is produced. This study shows that the way in which recovery from hypoglycemia takes place in people with type 1 diabetes could play an important role in favoring the appearance of endothelial dysfunction, oxidative stress, and inflammation, widely recognized cardiovascular risk factors.

Efficacy and safety of insulin lispro protamine suspension as basal supplementation in patients with type 2 diabetes

The three currently marketed long-acting insulin analogs, glargine, detemir and insulin lispro protamine suspension (ILPS), represent the most significant advances in basal insulin supplementation since the 1940s and 1950s and the introduction of the intermediate-acting NPH (neutral protamine Hagedorn) insulin. As injection of NPH insulin lacks chronic maintenance of a steady-state low-level basal insulin during fasting periods, which can also expose patients to unpredictable nocturnal hypoglycemia, long-acting insulin analogs have been developed to overcome this important limitation of NPH insulin. ILPS is a protamine-based, intermediate-acting insulin formulation of the short-acting analog insulin lispro: its pharmacokinetic and pharmacodynamic characteristics are quite similar to the other basal insulin analogs glargine and detemir. In recent head-to-head randomized controlled trials of insulin-naïve patients with type 2 diabetes, ILPS achieved similar glycemic control compared with glargine or detemir. ILPS administered once daily is an effective and safe way to maintain a steady-state low-level basal insulin during night time, not dissimilar from that currently obtained with a one-day glargine or detemir administration.

Proportion of patients at HbA1c target <7% with eight classes of antidiabetic drugs in type 2 diabetes: systematic review of 218 randomized controlled trials with 78 945 patients

AIM

We assessed the efficacy of eight classes of diabetes medications used in current clinical practice [metformin, sulphonylureas, α-glucosidase inhibitors, thiazolidinediones, glinides, dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 (GLP-1) analogues and insulin analogues] to reach the HbA1c target <7% in type 2 diabetes.

METHODS

MEDLINE, EMBASE and the Cochrane CENTRAL were searched from inception through April 2011 for randomized controlled trials (RCTs) involving antidiabetic drugs. RCTs had to report the effect of any diabetes medication on the HbA1c levels, to include at least 30 subjects in every arm of the study, and to report the effect of therapy after a minimum of 12 weeks. Data were summarized across studies using random-effects meta-regression.

RESULTS

A total of 218 RCTs (339 arms and 77 950 patients) met the inclusion criteria. The proportion of patients who achieved the HbA1c goal ranged from 25.9% (95% CI 18.5-34.9) with α-glucosidase inhibitors to 63.2% (54.1-71.5) with the long-acting GLP-1 analogue. There was a progressive decrease of the proportion of patients at target for each 0.5% increase in baseline HbA1c, ranging from 57.8% for HbA1c ≤7.5% to 20.8% for HbA1c ≥10% (p for trend <0.0001), with some difference between insulin and non-insulin drugs: for insulin, the proportion of patients at goal reached a plateau for basal HbA1c value >9.0% with no further decrease, whereas for non-insulin drugs the relationship was continuous without any evidence of plateau.

CONCLUSIONS

There is a considerable variability with regard to attainment of HbA1c goal of <7% among the different classes of diabetes medications; baseline HbA1c is an important determinant of observed efficacy.

The link between erectile and cardiovascular health: the canary in the coal mine

Lifestyle and nutrition have been increasingly recognized as central factors influencing vascular nitric oxide (NO) production and erectile function. This review underscores the importance of NO as the principal mediator influencing cardiovascular health and erectile function. Erectile dysfunction (ED) is associated with smoking, excessive alcohol intake, physical inactivity, abdominal obesity, diabetes, hypertension, and decreased antioxidant defenses, all of which reduce NO production. Better lifestyle choices; physical exercise; improved nutrition and weight control; adequate intake of or supplementation with omega-3 fatty acids, antioxidants, calcium, and folic acid; and replacement of any testosterone deficiency will all improve vascular and erectile function and the response to phosphodiesterase-5 inhibitors, which also increase vascular NO production. More frequent penile-specific exercise improves local endothelial NO production. Excessive intake of vitamin E, calcium, l-arginine, or l-citrulline may impart significant cardiovascular risks. Interventions discussed also lower blood pressure or prevent hypertension. Certain angiotensin II receptor blockers improve erectile function and reduce oxidative stress. In men aged <60 years and in men with diabetes or hypertension, erectile dysfunction can be a critical warning sign for existing or impending cardiovascular disease and risk for death. The antiarrhythmic effect of omega-3 fatty acids may be particularly crucial for these men at greatest risk for sudden death. In conclusion, by better understanding the complex factors influencing erectile and overall vascular health, physicians can help their patients prevent vascular disease and improve erectile function, which provides more immediate motivation for men to improve their lifestyle habits and cardiovascular health.

GLP-1 receptor agonists and HBA1c target of <7% in type 2 diabetes: meta-analysis of randomized controlled trials

OBJECTIVE

Glucagon-like peptide-1 (GLP-1) receptor agonists are available for the treatment of type 2 diabetes. We assessed the efficacy of exenatide and liraglutide to reach the HbA(1c) target of <7% in people with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We conducted an electronic search for randomized controlled trials (RCTs) involving GLP-1 agonists through September 2010. RCTs were included if they lasted at least 12 weeks, included 30 patients or more, and reported the proportion of patients reaching the HbA(1c) target of <7%.

RESULTS

A total of 25 RCTs reporting 28 comparisons met the selection criteria, which included 9771 study participants evaluated for the primary endpoint, 5083 treated with a GLP-1 agonist and 4688 treated with placebo or a comparator drug. GLP-1 agonists showed a statistically significant reduction in HbA(1c) compared to placebo and the proportion of participants achieving the HbA(1c) goal <7% was 46% for exenatide, 47% for liraglutide, and 63% for exenatide LAR (long-acting release). Moreover, the reduction of the HbA(1c) level and the rate of HbA(1c) goal attainment were higher for both exenatide LAR and liraglutide, as compared to comparator drugs. Higher rates of hypoglycemia with exenatide b.i.d. and liraglutide compared to placebo were associated with the concomitant use of a sulfonylurea. Exenatide b.i.d. and liraglutide were associated with weight loss compared to placebo or other antidiabetic drugs. Baseline HbA(1c) was the best predictor for achievement of A1c target (overall weighted R(2) value = 0.513, p < 0.001).

CONCLUSIONS

A greater proportion of patients with type 2 diabetes can achieve the HbA(1c) goal <7% with GLP-1 agonists compared to placebo or other antidiabetic drugs; in absolute terms, exenatide LAR was best for the attainment of the HbA(1c) goal.

Multiple HbA1c targets and insulin analogues in type 2 diabetes: a systematic review

PROBLEM

Insulin analogues are increasingly used in patients with type 2 diabetes. We performed a systematic review of randomized controlled trials (RCTs) to assess the role of insulin analogues to reach different hemoglobin A1c (HbA1c) targets (from 6.5% to 8%) in type 2 diabetic patients.

METHODS

RCTs involving insulin regimens (basal, prandial, biphasic, and basal-bolus) with insulin analogues in type 2 diabetes were identified through electronic searches (MEDLINE, EMBASE, CINAHL, and The Cochrane Library) through August 2010. We included any study arm of RCTs if they were at least 12 weeks in duration, and reported HbA1c as an outcome and the proportion of diabetic patients reaching the HbA1c target of <7%. The proportion of patients with HbA1c <6.5%, <7.0%, <7.5%, and <8.0% was estimated using mean and standard deviation of HbA1c at the end of treatment.

RESULTS

We identified 53 RCTs, with 92 arms, and 32,689 patients. The proportion of patients at target was highest with the basal-bolus regimen, and ranged from 27.8% (95% CI, 22.2-34%) for the HbA1c target <6.5% to 88% (CI 83-92%) for the HbA1c target <8%. Biphasic insulin regimen ranked second at any HbA1c target, while prandial and basal regimens alternated across different HbA1c targets.

CONCLUSIONS

At any HbA1c target, basal-bolus insulin regimens with insulin analogues obtained the best results, which may be useful for detailing the best treatment effect in individual patients.

Dipeptidyl peptidase-4 inhibitors and HbA1c target of <7% in type 2 diabetes: meta-analysis of randomized controlled trials

AIM

We assessed the efficacy of dipeptidyl peptidase-4 (DPP-4) inhibitors vildagliptin, sitagliptin, saxagliptin and alogliptin to reach the haemoglobin HbA1c target of <7% in people with type 2 diabetes.

METHODS

We conducted an electronic search for randomized controlled trials (RCTs) involving DPP-4 inhibitors through September 2010. RCTs were included if they lasted at least 12 weeks, included 30 patients or more and reported the proportion of patients reaching the HbA1c target of <7%.

RESULTS

A total of 43 RCTs reporting 52 comparisons met the selection criteria, which included 19 101 study participants evaluated for the primary endpoint, 10 467 treated with a DPP-4 inhibitor and 8634 treated with placebo or a comparator drug. DPP-4 inhibitors showed a statistically significant reduction in HbA1c compared to placebo and approximately 40% of participants achieved the HbA1c goal of <7%: this was associated with weight neutrality and no greater hypoglycaemia. The reduction of the HbA1c level and the rate of HbA1c goal attainment was not different from comparator drugs, with similar hypoglycaemia, and different effect on weight owing to the nature of comparator (metformin, sulfonylurea or glitazones). Baseline HbA1c was the best predictor for achievement of A1C target (overall weighted r(2) value = 0.410, p < 0.001).

CONCLUSIONS

A greater proportion of type 2 diabetic patients can achieve the HbA1c goal <7% with DPP-4 inhibitors compared to placebo, with no weight gain, and no hypoglycaemic risk when used alone; DPP-4 inhibitors were not different from comparator drugs.

The effect of Mediterranean diet on metabolic syndrome and its components: a meta-analysis of 50 studies and 534,906 individuals

OBJECTIVES

The aim of this study was to meta-analyze epidemiological studies and clinical trials that have assessed the effect of a Mediterranean diet on metabolic syndrome (MS) as well as its components.

BACKGROUND

The Mediterranean diet has long been associated with low cardiovascular disease risk in adult population.

METHODS

The authors conducted a systematic review and random effects meta-analysis of epidemiological studies and randomized controlled trials, including English-language publications in PubMed, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials until April 30, 2010; 50 original research studies (35 clinical trials, 2 prospective and 13 cross-sectional), with 534,906 participants, were included in the analysis.

RESULTS

The combined effect of prospective studies and clinical trials showed that adherence to the Mediterranean diet was associated with reduced risk of MS (log hazard ratio: -0.69, 95% confidence interval [CI]: -1.24 to -1.16). Additionally, results from clinical studies (mean difference, 95% CI) revealed the protective role of the Mediterranean diet on components of MS, like waist circumference (-0.42 cm, 95% CI: -0.82 to -0.02), high-density lipoprotein cholesterol (1.17 mg/dl, 95% CI: 0.38 to 1.96), triglycerides (-6.14 mg/dl, 95% CI: -10.35 to -1.93), systolic (-2.35 mm Hg, 95% CI: -3.51 to -1.18) and diastolic blood pressure (-1.58 mm Hg, 95% CI: -2.02 to -1.13), and glucose (-3.89 mg/dl, 95% CI:-5.84 to -1.95), whereas results from epidemiological studies also confirmed those of clinical trials.

CONCLUSIONS

These results are of considerable public health importance, because this dietary pattern can be easily adopted by all population groups and various cultures and cost-effectively serve for primary and secondary prevention of the MS and its individual components.

Relationship of baseline HbA1c, HbA1c change and HbA1c target of < 7% with insulin analogues in type 2 diabetes: a meta-analysis of randomised controlled trials

AIM

We performed a meta-analysis of randomised controlled trials (RCTs) with insulin analogues in type 2 diabetes utilising a least-squared regression model in order to assess the relationship between baseline HbA1c, the magnitude of HbA1c decrease and attainment of HbA1c target of < 7%.

METHODS

Randomised controlled trials involving insulin regimens (basal, prandial, biphasic and basal-bolus) were identified through electronic searches (MEDLINE, EMBASE, CINAHL and The Cochrane Library) through September 2010. We included any study arm of RCTs if they were at least 12 weeks in duration; the number of patients in any arm was more than 30 and reported the baseline HbA1c and change from baseline HbA1c.

RESULTS

We found 87 studies, with a total of 135 arms, and 38,803 patients. The weighted R(2) values for the overall analysis assessing the association between baseline HbA1c and absolute change in HbA1c or the proportion of patients at target were 0.485 (p < 0.001) and 0.146 (p < 0.001), respectively. Subanalyses of insulin regimens for the association between basal HbA1c and absolute decrease of HbA1c produced weighted R(2), which were significant for all insulin regimens with the highest association for basal-bolus (R(2) = 0.719, p < 0.001).

CONCLUSIONS

The strong positive relationship between baseline HbA1c and the magnitude of HbA1c change we found in RCTs using insulin analogues in type 2 diabetes should be considered when assessing the clinical efficacy of insulin therapies.

Effects of pioglitazone versus metformin on circulating endothelial microparticles and progenitor cells in patients with newly diagnosed type 2 diabetes--a randomized controlled trial

AIM

Endothelial microparticles (EMPs) and endothelial progenitor cells (EPCs) are markers of endothelial injury and repair. We compared the effects of pioglitazone versus metformin on the circulating numbers of EMPs and EPCs in patients with newly diagnosed type 2 diabetes.

METHODS

This was a randomized, double-blind, comparator-controlled, 24-week single-centre trial conducted in a Teaching Hospital in Naples, Italy. One hundred and ten people with newly diagnosed type 2 diabetes who were never treated with antihyperglycaemic drugs and had haemoglobin A1c (HbA1c) levels between 7 and 10% were given pioglitazone hydrochloride (15-45 mg/day) (n = 55) or metformin (1000-2000 mg/day) (n = 55) as an active comparator. Absolute change from baseline to final visit in circulating EMPs and EPCs and their ratio were the main outcomes.

RESULTS

Baseline characteristics did not differ between the study groups. The decrease in circulating EMPs CD31+ [intergroup difference, -32 counts/µl (95% CI -51 to -9)] and the increase in EPCs CD34+/KDR+ [intergroup difference, 33 cells/10(6) events (95% CI 13 to 55)] were greater with pioglitazone versus metformin. EMPs/EPCs ratio was reduced with pioglitazone and unchanged with metformin [difference, -1.5 (95% CI -2.6 to -0.5), p < 0.001]. Participants assigned to pioglitazone gained more weight and experienced greater improvements in some coronary risk measures [high-density lipoprotein (HDL)-cholesterol, triglycerides, adiponectin and C-reactive protein (CRP)] than did those assigned to metformin.

CONCLUSION

Compared with metformin, pioglitazone treatment improved the imbalance between endothelial damage and repair capacity and led to more favourable changes in coronary risk factors in patients with newly diagnosed type 2 diabetes.

Treatment regimens with insulin analogues and haemoglobin A1c target of <7% in type 2 diabetes: a systematic review

We conducted a systematic review of randomized controlled trials that evaluated the effectiveness of insulin regimens (basal, biphasic, prandial, and basal-bolus) with insulin analogues to reach the haemoglobin A1c target of <7% in patients with type 2 diabetes. We identified 48 trials, with 85 arms and 30,588 patients. There were 38 arms using basal insulin, with 17,588 patients, and a primary outcome of 41.4% (95% CI=35.6-47.4%); 26 arms using biphasic insulin, with 9237 patients, and a primary outcome of 46.5% (40.8-52.3%); 9 arms using prandial insulin, with 1605 patients, and a primary outcome of 39.6% (95% CI, 28.6-51.3%); and 12 arms using basal-bolus insulin, with 2114 patients, and a primary outcome of 53.9% (43.5-64). The high heterogeneity was related, in part, to first time insulin use, final insulin dose, and use of oral drug. The overall incidence of hypoglycaemia ranged from 0 to 4.71 events/patient/30 days; weight gain ranged from 1.75 kg for basal to 3 kg for biphasic insulin. The HbA1c target of <7% can be achieved in a percentage of type 2 diabetic patients ranging from 40% to 54% depending on the particular insulin regimen.

The possible protective role of glucagon-like peptide 1 on endothelium during the meal and evidence for an "endothelial resistance" to glucagon-like peptide 1 in diabetes

OBJECTIVE

Glucagon-like peptide 1 (GLP-1) stimulates insulin secretion. However, GLP-1 also improves endothelial function in diabetes.

RESEARCH DESIGN AND METHODS

Sixteen type 2 diabetic patients and 12 control subjects received a meal, an oral glucose tolerance test (OGTT), and two hyperglycemic clamps, with or without GLP-1. The clamps were repeated in diabetic patients after 2 months of strict glycemic control.

RESULTS

During the meal, glycemia, nitrotyrosine, and plasma 8-iso prostaglandin F2α (8-iso-PGF2a) remained unchanged in the control subjects, whereas they increased in diabetic patients. Flow-mediated vasodilation (FMD) decreased in diabetes, whereas GLP-1 increased in both groups. During the OGTT, an increase in glycemia, nitrotyrosine, and 8-iso-PGF2a and a decrease in FMD were observed at 1 h in the control subjects and at 1 and 2 h in the diabetic patients. In the same way, GLP-1 increased in both groups at the same levels of the meal. During the clamps, in both the control subjects and the diabetic patients, a significant increase in nitrotyrosine and 8-iso-PGF2a and a decrease in FMD were observed, effects that were significantly reduced by GLP-1. After improved glycemic control, hyperglycemia during the clamps was less effective in producing oxidative stress and endothelial dysfunction and the GLP-1 administration was most effective in reducing these effects.

CONCLUSIONS

Our data suggest that during the meal GLP-1 can simultaneously exert an incretin effect on insulin secretion and a protective effect on endothelial function, reasonably controlling oxidative stress generation. The ability of GLP-1 in protecting endothelial function seems to depend on the level of glycemia, a phenomenon already described for insulin secretion.

Efficacy of insulin analogs in achieving the hemoglobin A1c target of <7% in type 2 diabetes: meta-analysis of randomized controlled trials

OBJECTIVE

Insulin analogs are increasingly used in patients with type 2 diabetes. We compared the effect of basal, biphasic, prandial, and basal-bolus insulin regimens with insulin analogs to reach the hemoglobin A(1c) (HbA(1c)) target of <7% in people with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We conducted an electronic search for randomized controlled trials (RCTs) involving insulin analogs. RCTs were included if they lasted at least 12 weeks, reported the proportion of diabetic patients reaching the HbA(1c) target of <7% (primary outcome), and the number of patients in any arm was >30.

RESULTS

We found 16 RCTs, with 20 comparisons and 7,759 patients. A greater proportion of patients achieved the HbA(1c) goal of <7% with both biphasic (odds ratio 1.88 [95% CI 1.38-2.55]) and prandial (2.07 [1.16-3.69]) insulin compared with basal insulin; this was associated for biphasic insulin with greater hypoglycemia (event/patient/30 days, mean difference, 0.34 [range 0-0.69]) and weight gain in kg (1.0 kg [0.28-1.73]). Compared with biphasic insulin, the basal-bolus regimen was associated with a greater chance to reach the HbA(1c) goal (odds ratio 1.75 [95% CI 1.11-2.77]), with no greater hypoglycemia or weight gain. The effect of insulin analogs on long-term diabetes complications is still lacking.

CONCLUSIONS

A greater proportion of type 2 diabetic patients can achieve the HbA(1c) goal <7% with biphasic or prandial insulin compared with basal insulin; in absolute terms, the basal-bolus regimen was best for the attainment of the HbA(1c) goal.

Recommendations for the use of cardiovascular tests in diagnosing diabetic autonomic neuropathy

Despite its prevalence, clinical and prognostic impact, diabetic autonomic neuropathy, is widely under-diagnosed. The need for training and expertise to perform the cardiovascular tests (usually the task of diabetologists) is one possible reason. The availability of computer-assisted systems has allowed a wider diffusion of testing, but has also highlighted the need for an adequate knowledge of physiopathological backgrounds for their correct application and interpretation. The recommendations presented here were developed by the Neuropathy Study Group of the Italian Society of Diabetology and then endorsed by the Italian Association for the Study of Neurovegetative System, to promote the widespread adoption of good clinical practice in diabetic cardiovascular autonomic testing by outlining main evidence-based aspects, i.e. which tests, how to perform them, adequate interpretation of the results and their diagnostic use, confounding conditions that can impact on tests reliability. Therefore, these recommendations include the essential aspects of the physiopathological substrate of the tests, the controversial points in their analysis, their diagnostic characteristics, as well as safety. Detailed information is given on the physiological (age, weight, body position, resting heart rate and blood pressure, respiratory pattern, exercise, meals, acute blood glucose changes) and pathophysiological confounding factors, with emphasis on the effects of drugs. Instructions on how to perform the tests and interpret their results are also considered together with indications of candidate patients and periodicity of testing. A patient instruction sheet on why and how to perform the tests is included. Finally, the specific requirements for computerized systems to perform and evaluate cardiovascular tests are provided.

Long-term effect of mediterranean-style diet and calorie restriction on biomarkers of longevity and oxidative stress in overweight men

We report the effects of a Mediterranean-style diet, with or without calorie restriction, on biomarkers of aging and oxidative stress in overweight men. 192 men were randomly assigned to either a Mediterranean-style diet or a conventional diet. The intervention program was based on implementation of a Mediterranean dietary pattern in the overweight group (MED diet group), associated with calorie restriction and increased physical activity in the obese group (lifestyle group). Both groups were compared with participants in two matched control groups (advice groups). After 2 years, there was a significant difference in weight loss between groups, which was −14 kg (95% CI −20 to −8) in lifestyle groups and −2.0 kg (−4.4 to 0) in the advice groups, with a difference of −11.9 kg (CI −19 to −4.7 kg, P < .001); moreover, there was a significant difference between groups at 2 years for insulin (P = .04), 8-iso-PGF2α (P = .037), glucose (P = .04), and adiponectin (P = .01). Prolonged adherence to a Mediterranean-style diet, with or without caloric restriction, in overweight or obese men is associated with significant amelioration of multiple risk factors, including a better cardiovascular risk profile, reduced oxidative stress, and improved insulin sensitivity.

Mediterranean diet and weight loss: meta-analysis of randomized controlled trials

BACKGROUND

The epidemiological evidence supporting a causal link between Mediterranean diets and body weight is contrasting. We evaluated the effect of Mediterranean diets on body weight in randomized controlled trials (RCTs) using a meta-analysis.

METHODS

We searched English and non-English publications in PubMed, Embase, Scopus, and the Cochrane Central Register of Controlled Trials from inception to January, 2010. Two evaluators independently selected and reviewed eligible studies. Sixteen randomized controlled trials, with 19 arms and 3,436 participants (1,848 assigned to a Mediterranean diet and 1,588 assigned to a control diet) were included.

RESULTS

In a random-effects meta-analysis of all 19 arms, the Mediterranean diet group had a significant effect on weight [mean difference between Mediterranean diet and control diet, -1.75 kg; 95% confidence interval (CI), -2.86 to -0.64 kg] and body mass index (mean difference, -0.57 kg/m², -0.93 to -0.21 kg/m²). The effect of Mediterranean diet on body weight was greater in association with energy restriction (mean difference, -3.88 kg, -6.54 to -1.21 kg), increased physical activity (-4.01 kg, -5.79 to -2.23 kg), and follow up longer than 6 months (-2.69 kg, -3.99 to -1.38 kg). No study reported significant weight gain with a Mediterranean diet.

CONCLUSIONS

Mediterranean diet may be a useful tool to reduce body weight, especially when the Mediterranean diet is energy-restricted, associated with physical activity, and more than 6 months in length. Mediterranean diet does not cause weight gain, which removes the objection to its relatively high fat content. These results may be useful for helping people to lose weight.

Prevention of type 2 diabetes by dietary patterns: a systematic review of prospective studies and meta-analysis

Lifestyle intervention may reduce the risk of type 2 diabetes. The aim of this study was to investigate the role of dietary patterns in the prevention of type 2 diabetes. We did an electronic search through November 30, 2009, for prospective studies that evaluated the role of dietary patterns in type 2 diabetes prevention. Ten large prospective studies were identified, comprising more than 190,000 subjects free of diabetes at baseline, followed for a time ranging from 2 to 23 years, and 8,932 cases of incident diabetes. All ten studies showed consistent results: Relative risk reduction of type 2 diabetes ranged from 83% to 15%. Overall, adherence to a healthy dietary pattern was associated with reduced risk of developing type 2 diabetes: Combined mean difference  = -0.39, 95% confidence interval (CI) -0.54 to -0.24. The reduced risk of developing type 2 diabetes was still present after sensitivity analysis (-0.34, 95% CI -0.44 to -0.24). Dietary patterns characterized by high consumption of fruit and vegetables, whole grains, fish, and poultry, and by decreased consumption of red meat, processed foods, sugar-sweetened beverages, and starchy foods may retard the progression of type 2 diabetes. Healthy diets can help people to live more years without type 2 diabetes.

Mediterranean diet and the metabolic syndrome: the end of the beginning

The metabolic syndrome is now both a public health and a clinical problem. The most recent estimates from the National Health and Nutrition Examination Survey (NHANES) 2003-2006 reported that approximately 34% of adults in the United States have the metabolic syndrome. The relationship between adherence to a Mediterranean diet and the prevalence of metabolic syndrome has been explored in cross-sectional studies with discordant results. Two prospective studies with a follow up of 6 and 7.5 years show that subjects with the highest adherence to a Mediterranean diet had lower cumulative incidence of metabolic syndrome than those with the lowest adherence. Two interventional trials document a positive effect of a Mediterranean diet on reversal of metabolic syndrome. The Mediterranean diet may be also useful to ameliorate liver function tests in obese patients with insulin resistance and diabetes. There is no consensus as to what diet is the optimal one for patients who have the metabolic syndrome. A Mediterranean diet that is moderately lower in carbohydrate (45%), and moderately higher in fat (35-40%), with less than 10% of saturated fat, may be beneficial for ameliorating features of the metabolic syndrome, including effects on insulin sensitivity, blood lipids, and liver function.

Effect of acute hyperglycaemia, long-term glycaemic control and insulin on endothelial dysfunction and inflammation in Type 1 diabetic patients with different characteristics

OBJECTIVE

To investigate the possibility of reversing endothelial dysfunction and inflammation by glucose normalization, antioxidants and insulin per se, in different subgroups of Type 1 diabetic patients.

METHODS

Three subgroups of Type 1 diabetic patients were studied: patients within 1 month of diagnosis (subgroup 1); patients with approximately 5 years' disease duration and with glycated haemoglobin (HbA(1c)) <or= 7.0% (subgroup 2) or > 7.0% since diagnosis (subgroup 3). Participants underwent four procedures: 2-h hyperglycaemic clamp followed by: (A) 12 h near-normalization of blood glucose, with the addition of vitamin C during the last 6 h; (B) 12-h vitamin C and near-normalization of blood glucose for the last 6 h; (C) both vitamin C and near-normalization of blood glucose for 12 h; (D) hyperglycaemic-hyperinsulinaemic clamp for 12 h, with the addition of vitamin C during the last 6 h.

RESULTS

After 2 h of hyperglycaemia, markers of endothelial dysfunction, nitrotyrosine, 8-iso prostaglandin F2alpha, soluble intercellular adhesion molecule-1, soluble vascular adhesion molecule-1, interleukin (IL)-6 and IL-18 were increased in all the subgroups. Levels were normalized, at all time points, by treatments A, B and C in the subgroups 1 and 2. In the third subgroup, levels were normalized only by the simultaneous normalization of blood glucose and vitamin C treatment. During treatment D, the levels were improved at 6 h in all the subgroups, but normalized at 12 h only after vitamin C in subgroups 1 and 2, but not in subgroup 3.

CONCLUSIONS

This study suggests that different subgroups of Type 1 diabetic patients react identically to acute hyperglycaemia and insulin, but differently to glucose normalization.

Prevention and control of type 2 diabetes by Mediterranean diet: a systematic review

We conducted a systematic review of the available studies that assessed the effect of a Mediterranean diet in type 2 diabetes. We searched publications up to 30 November 2009. Seventeen studies were included. Two large prospective studies report a substantially lower risk (83% and 35%, respectively) of type 2 diabetes in healthy people or in post-infarct patients with the highest adherence to a Mediterranean diet. Five randomized controlled trials have evaluated the effects of a Mediterranean diet, as compared with other commonly used diets, on indices of glycaemic control in subjects with type 2 diabetes. Improvement of fasting glucose and HbA1c levels was greater with a Mediterranean diet and ranged from 7 to 40mg/dl for fasting glucose, and from 0.1 to 0.6% for HbA1c. No trial reported worsening of glycaemic control with a Mediterranean diet. Two controlled trials in a secondary prevention setting demonstrated that post-infarct patients, including diabetic patients, had cardiovascular benefits from a Mediterranean diet. The evidence so far accumulated suggests that adopting a Mediterranean diet may help prevent type 2 diabetes, and also improve glycaemic control and cardiovascular risk in persons with established diabetes.

Olive oil and health: summary of the II international conference on olive oil and health consensus report, Jaén and Córdoba (Spain) 2008

Olive oil (OO) is the most representative food of the traditional Mediterranean Diet (MedDiet). Increasing evidence suggests that monounsaturated fatty acids (MUFA) as a nutrient, OO as a food, and the MedDiet as a food pattern are associated with a decreased risk of cardiovascular disease, obesity, metabolic syndrome, type 2 diabetes and hypertension. A MedDiet rich in OO and OO per se has been shown to improve cardiovascular risk factors, such as lipid profiles, blood pressure, postprandial hyperlipidemia, endothelial dysfunction, oxidative stress, and antithrombotic profiles. Some of these beneficial effects can be attributed to the OO minor components. Therefore, the definition of the MedDiet should include OO. Phenolic compounds in OO have shown antioxidant and anti-inflammatory properties, prevent lipoperoxidation, induce favorable changes of lipid profile, improve endothelial function, and disclose antithrombotic properties. Observational studies from Mediterranean cohorts have suggested that dietary MUFA may be protective against age-related cognitive decline and Alzheimer's disease. Recent studies consistently support the concept that the OO-rich MedDiet is compatible with healthier aging and increased longevity. In countries where the population adheres to the MedDiet, such as Spain, Greece and Italy, and OO is the principal source of fat, rates of cancer incidence are lower than in northern European countries. Experimental and human cellular studies have provided new evidence on the potential protective effect of OO on cancer. Furthermore, results of case-control and cohort studies suggest that MUFA intake including OO is associated with a reduction in cancer risk (mainly breast, colorectal and prostate cancers).