Effect of insulin on the soluble receptor for advanced glycation end products (RAGE).

AIMS: The receptor for advanced glycation end products (RAGE) plays an important role in the pathogenesis of diabetic complications. RAGE transcript splicing generates a number of isoforms, including a full-length membrane-bound receptor and a soluble isoform, endogenous secretory RAGE (esRAGE). Soluble forms of the receptor (sRAGE) can also be formed by ectodomain shedding of the membrane-associated receptor. We have evaluated serum levels of sRAGE and esRAGE in Chinese patients with Type 1 diabetes and investigated the effect of insulin on the generation of esRAGE and sRAGE in vitro. METHODS: Serum sRAGE and esRAGE were measured by ELISA. The in vitro effect of insulin was investigated by incubating THP-1 macrophages with insulin and RAGE isoforms in cell lysate and conditioned media determined. RESULTS: In patients with diabetes, both serum esRAGE and sRAGE were significantly higher than in age-matched healthy subjects without diabetes. In vitro, insulin increased esRAGE and total RAGE isoform expression in cell lysate on a western blot, and reverse transcription-polymerase chain reaction showed an increase in esRAGE and full-length RAGE mRNA. This was accompanied by an increase in esRAGE and sRAGE in cell conditioned media. Pretreatment of THP-1 cells with a general metalloproteinase inhibitor GM6001 significantly reduced the production of sRAGE, suggesting that insulin also increased the cleavage of full-length cell surface RAGE to form sRAGE. CONCLUSIONS: Chinese patients with Type 1 diabetes have higher serum levels of esRAGE and sRAGE. In vitro, insulin not only increases both full-length RAGE and esRAGE expression, but can also stimulate the shedding of sRAGE from the membrane-bound receptor.

Thiazolidinediones and fracture risk in patients with Type 2 diabetes.

Thiazolidinediones are widely used effective drugs for the management of hyperglycaemia in Type 2 diabetes and may provide additional metabolic benefits. Any advantages of these agents need to be considered in the context of any potential risk from adverse events. Recent evidence from several sources, including large-scale randomized controlled trials and observational studies, suggests that long-term use of thiazolidinediones is associated with bone loss and an increased risk of fractures in women with Type 2 diabetes. As patients with Type 2 diabetes are already at high risk for fractures, the clinical relevance of this reported association with thiazolidinedione therapy deserves careful consideration. Generally, the fracture risk with thiazolidinediones appears similar in magnitude to that associated with several other widely used drug classes, although there are unanswered questions regarding susceptibility factors, differential effects on bone sites and potential management approaches. This article provides a comprehensive overview of the evidence for an increase in fracture risk with thiazolidinediones and places it in the context of recent analyses of fracture risk with other commonly used drug classes. The potential clinical implications of any association are also discussed.

High-density lipoprotein-cholesterol and not HbA1c was directly related to cardiovascular outcome in PROactive.

AIM: In PROactive, pioglitazone reduced the incidence of death, myocardial infarction and stroke, and significantly improved HbA1c, systolic blood pressure (SBP), triglycerides and high-density lipoprotein (HDL)-cholesterol relative to placebo. As these glycaemic and lipid parameters are major cardiovascular (CV) risk factors, we assessed their separate contribution to the reduced incidence of CV outcomes. METHODS: Patients (n = 5238) with type 2 diabetes and macrovascular disease were randomized to 45 mg pioglitazone or placebo. Relationships among treatment, outcome (time to first event of all-cause mortality, myocardial infarction and stroke) and 10 laboratory measurements and vital signs were investigated using log-linear models. Continuous variable measurements (percent changes from baseline to average of all postbaseline values prior to censoring) were made discrete by categorizing into tertiles. Log-linear models were fitted to multiway tables of discrete data and analysis of deviance used to summarize sources of variation in the data. RESULTS: Although pioglitazone treatment was associated with a decrease in HbA1c and an increase in HDL-cholesterol (HDL-C), only the change from baseline HDL-C predicted the outcome (χ(2) = 28.89, p < 0.0001). No other variables, including HbA1c, triglycerides and systolic blood pressure, showed significant direct associations with outcome. When the analysis was extended to include baseline statin use, this was associated with an improved outcome independently of HDL-C changes. CONCLUSIONS: This post hoc analysis suggests that HDL-C, but probably not HbA1c, is a driver of pioglitazone's favourable influence on CV outcome.

Lipid-altering efficacy and safety profile of combination therapy with ezetimibe/statin vs. statin monotherapy in patients with and without diabetes: an analysis of pooled data from 27 clinical trials.

AIM: This post hoc analysis compared the lipid-altering efficacy and safety of ezetimibe 10 mg plus statin (EZE/statin) vs. statin monotherapy in hypercholesterolaemic patients with and without diabetes. METHODS: A pooled analysis of 27 previously published, randomized, double-blind, active- or placebo-controlled clinical trials comprising 21 794 adult patients with (n = 6541) and without (n = 15253) diabetes receiving EZE/statin or statin alone for 4-24 weeks evaluated percentage change from baseline in lipids and other parameters. Consistency of the treatment effect across the subgroups was tested using treatment × subgroup interaction. No multiplicity adjustments were made. RESULTS: Treatment effects within both subgroups were generally consistent with the overall population. EZE/statin was more effective than statin alone in improving low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides (TGs), non-HDL-C, apolipoprotein (apo) B and high-sensitivity C-reactive protein (hs-CRP) in the overall population and both subgroups. Patients with diabetes achieved significantly larger reductions in LDL-C, TC and non-HDL-C compared with non-diabetic patients. Incidences of adverse events or creatine kinase elevations were similar between groups. A small but significantly higher incidence of alanine aminotransferase or aspartate aminotransferase elevations was seen in patients receiving EZE/statin (0.6%) vs. statin monotherapy (0.3%) in the overall population. CONCLUSIONS: Treatment with EZE/statin vs. statin monotherapy provided significantly larger reductions in LDL-C, TC, TG, non-HDL-C, apo B and hs-CRP and significantly greater increases in HDL-C, with a similar safety profile in patients with and without diabetes. Reductions in LDL-C, TC and non-HDL-C were larger in patients with diabetes than in patients without diabetes.

All-cause and cardiovascular mortality in treated patients with severe hypertriglyceridaemia: A long-term prospective registry study.

OBJECTIVE: To examine all-cause and cardiovascular mortality in patients with severe hypertriglyceridaemia. METHODS: 337 patients aged less than 80 years (47 with diabetes, 75 women) with a fasting triglyceride concentration on at least two occasions of >5.0mmol/l were registered by 21 lipid clinics in the United Kingdom and followed prospectively between 1980 and 2008 for 4353 person-years. The standardised mortality ratio (SMR) was calculated by comparison with the general population. RESULTS: The mean untreated total cholesterol concentration was 9.8 (SD 3.6)mmol/l for men and 11.9 (7.2)mmol/l for women and the corresponding geometric mean triglyceride concentration was 12.6 (inter-quartile range 7.3, 21.6) and 15.7 (8.2, 29.2)mmol/l. There were 70 deaths, including 35 from CHD and 7 from stroke. The SMR for CHD was raised at 327 (95% confidence intervals 228, 455; p<0.0001) and remained elevated after excluding patients with diabetes at registration (SMR=287, 95% CI 190, 419; p<0.0001), and after excluding patients with CHD at registration (SMR=259, 95% CI 158, 400; p=0.0003). The increased SMR was most marked in younger men aged 40-59 years (SMR=544, 95% CI 304, 897; p<0.0001). The SMR for stroke for patients aged 20-79 years was raised at 262 (95% CI 105, 540; p=0.04), as was all-cause mortality at 164 (95% CI 129, 208; p<0.001). CONCLUSION: Severe hypertriglyceridaemia is associated with a substantially increased mortality from cardiovascular disease, even in the absence of diabetes. In addition to lowering triglyceride concentrations to reduce the risk of pancreatitis, treatment should aim to reduce the overall cardiovascular risk.

Is the ADA/EASD algorithm for the management of type 2 diabetes (January 2009) based on evidence or opinion? A critical analysis.

The ADA and the EASD recently published a consensus statement for the medical management of hyperglycaemia in patients with type 2 diabetes. The authors advocate initial treatment with metformin monotherapy and lifestyle modification, followed by addition of basal insulin or a sulfonylurea if glycaemic goals are not met (tier 1 recommendations). All other glucose-lowering therapies are relegated to a secondary (tier 2) status and only recommended for selected clinical settings. In our view, this algorithm does not offer physicians and patients the appropriate selection of options to individualise and optimise care with a view to sustained control of blood glucose and reduction both of diabetes complications and cardiovascular risk. This paper critically assesses the basis of the ADA/EASD algorithm and the resulting tiers of treatment options.

Effects of atorvastatin on serum soluble receptors for advanced glycation end-products in type 2 diabetes.

OBJECTIVE: The receptor for advanced glycation end-products (RAGE) plays an important role in the pathogenesis of diabetic complications and atherosclerosis. Interfering with the activation of RAGE by using a soluble form of the receptor (sRAGE) ameliorates the vascular complications of diabetes in animal models. We have investigated whether statin can influence the expression of sRAGE and esRAGE (a splice variant of sRAGE) in vitro and in vivo. METHODS: THP-1 cells were incubated with atorvastatin in vitro and sRAGE and esRAGE in the medium was measured by Western immunoblot. Serum levels of sRAGE and esRAGE were measured by ELISA in archived serum samples from a previous randomized double-blind placebo-controlled clinical trial that explored the cardiovascular effects of atorvastatin in hypercholesterolemic Chinese type 2 diabetic patients. RESULTS: sRAGE and esRAGE were induced by atorvastatin in a time- and dose-dependent manner in THP-1 cells. In the diabetic patients, there was a significant increase in serum sRAGE (p<0.05) and esRAGE (p<0.01) in the atorvastatin group at 6-month, but no change in placebo group. Serum esRAGE was higher in atorvastatin group than placebo group [median 240.5pg/ml (interquartile range 186.5-377.3) vs 194.8pg/ml (124.1-347.9) respectively, p<0.01] at 6-month, whereas the differences in sRAGE did not reach statistical significance (p=0.051). There was a correlation between the increase of serum esRAGE and reduction of serum LDL (r=-0.36, p=0.001). CONCLUSIONS: Statins are known to have pleiotropic effects and we have shown that atorvastatin can increase circulating esRAGE levels in type 2 diabetic patients.

Long-term glycaemic effects of pioglitazone compared with placebo as add-on treatment to metformin or sulphonylurea monotherapy in PROactive (PROactive 18).

AIMS: To assess the long-term glycaemic effects, concomitant changes in medications and initiation of permanent insulin use (defined as daily insulin use for a period of > or = 90 days or ongoing use at death/final visit) with pioglitazone vs. placebo in diabetic patients receiving metformin or sulphonylurea monotherapy at baseline in the PROspective pioglitAzone Clinical Trial in macroVascular Events (PROactive). METHODS: In PROactive, patients with Type 2 diabetes and macrovascular disease were randomized to pioglitazone (force titrated to 45 mg/day) or placebo, in addition to other existing glucose-lowering therapies. In a post-hoc analysis, we categorized patients not receiving insulin at baseline and treated by oral monotherapy into two main cohorts: add-on to metformin alone (n = 514) and sulphonylurea alone (n = 1001). The follow-up averaged 34.5 months. RESULTS: There were significantly greater reductions in glycated haemoglobin (HbA(1c)) with pioglitazone than with placebo and more pioglitazone-treated patients achieved HbA(1c) targets, irrespective of the baseline oral glucose-lowering regimen and despite a decrease in the use of other glucose-lowering agents. Approximately twice as many in the placebo groups progressed to permanent insulin use than in the pioglitazone groups across the two cohorts: 3.4% for pioglitazone and 6.5% for placebo when added to metformin monotherapy and 6.3% and 14.8%, respectively, when added to sulphonylurea monotherapy. The overall safety of both dual therapies was good. CONCLUSIONS: Intensifying an existing oral monotherapy regimen to a dual oral regimen by adding pioglitazone resulted in sustained improvements in glycaemic control and reduced progression to insulin therapy. The efficacy and safety of adding pioglitazone to either metformin monotherapy or sulphonylurea monotherapy were good.

Long-term glycaemic control with metformin-sulphonylurea-pioglitazone triple therapy in PROactive (PROactive 17).

AIMS: We assessed the long-term glycaemic effects and the safety profile of triple therapy with the addition of pioglitazone vs. placebo in patients with Type 2 diabetes treated with combined metformin-sulphonylurea therapy in the PROspective pioglitAzone Clinical Trial In macroVascular Events (PROactive). METHODS: In a post-hoc analysis, we identified patients treated with metformin plus sulphonylurea combination therapy and not receiving insulin at baseline (n = 1314). In those patients, we compared the effects of pioglitazone (force-titrated to 45 mg/day, n = 654) vs. placebo (n = 660) on glycated haemoglobin (HbA(1c)) reduction, concomitant changes in medications and initiation of permanent insulin use (defined as daily insulin use for a period of > or = 90 days or ongoing use at death/final visit). RESULTS: Significantly greater reductions in HbA(1c) and greater proportions of patients with HbA(1c) at target were noted with pioglitazone vs, placebo, despite a decrease in the use of other oral glucose-lowering agents. There was an approximate twofold increase in progression to permanent insulin use in the placebo group vs. the pioglitazone group: 31.1 vs. 16.1%, respectively, when added to combination therapy. The overall safety of the metformin-sulphonylurea-pioglitazone triple therapy was good. CONCLUSIONS: Intensifying an existing dual oral therapy regimen to a triple oral regimen by adding pioglitazone to the classical metformin-sulphonylurea combination resulted in sustained improvements in glycaemic control and reduced progression to insulin therapy. The advantages and disadvantages of adding pioglitazone instead of adding basal insulin should be assessed further.

Apolipoproteins, cardiovascular risk and statin response in type 2 diabetes: the Collaborative Atorvastatin Diabetes Study (CARDS).

AIMS/HYPOTHESIS: Controversy surrounds whether the ratio of apolipoprotein B (ApoB) to apolipoprotein A-I (ApoA-I) is the best lipoprotein discriminator of CHD risk in non-diabetic populations, but the issue has never been investigated in type 2 diabetes. METHODS: In 2,627 participants without known vascular disease in the Collaborative Atorvastatin Diabetes Study, ApoB, ApoA-I, LDL-cholesterol (LDLC) and HDL-cholesterol (HDLC) were assayed at baseline. RESULTS: There were 108 CHD and 59 stroke endpoints over 3.9 years. The ApoB:A-I ratio at baseline was the lipoprotein variable most closely predicting CHD risk both by comparison of the hazard ratio for a 1 SD change or tertiles of frequency distribution. The areas under the receiver-operator curve for the ApoB:ApoA-I and the LDLC to HDLC [corrected] ratios, although not significantly different from each other, were greater (p = 0.0005 and p = 0.0125 respectively) than that of non-HDLC:HDLC. The 27% decrease in the ApoB:ApoA-I ratio on atorvastatin predicted a 32% (95% CI 5.4-51.2%) risk reduction in CHD, close to the 36% decrease observed. Neither the ApoB:ApoA-I nor any other lipoprotein concentration or ratio predicted the stroke outcome. CONCLUSIONS/INTERPRETATION: Overall, the ApoB:ApoA-I ratio improved on the non-HDLC:HDLC ratio in predicting CHD, but, depending on the assessment chosen, its superiority over LDLC:HDLC may be marginal. The statin-induced decrease in stroke risk may not be lipoprotein mediated. TRIAL REGISTRATION: ClinicalTrials.gov NCT00327418. FUNDING: The study was supported by unrestricted grants from Diabetes UK, the Department of Health and Pfizer to the University of Manchester and to University College, London.

Impact of peripheral arterial disease in patients with diabetes--results from PROactive (PROactive 11).

We compared cardiovascular disease outcomes according to the presence of peripheral arterial disease (PAD) at baseline in a post hoc analysis from the PROactive study. Of the 5238 patients in PROactive (a study of pioglitazone versus placebo in patients with type 2 diabetes and macrovascular disease; mean follow-up=34.5 months), 1274 had PAD at baseline (619=pioglitazone; 655=placebo). Patients with PAD at baseline showed significantly higher rates of the primary endpoint, main secondary endpoint, all-cause mortality (all P<0.0001), and stroke (P=0.0175) than those with no PAD at baseline. The risk of PAD alone was similar to that of myocardial infarction alone. In patients with no PAD at baseline, the event rates of the primary endpoint (P=0.0160), main secondary endpoint (P=0.0453), and acute coronary syndrome (P=0.0287) were significantly lower with pioglitazone than with placebo. This beneficial effect of pioglitazone was not seen in patients with PAD at baseline. In the total population, there was a higher frequency of leg revascularizations with pioglitazone than placebo-this was wholly due to first events that occurred within the initial 12 months of treatment. The presence of PAD increased the risk of all major cardiovascular events. Those without PAD at baseline seemed to benefit more from pioglitazone treatment than the overall PROactive population.

Stroke prediction and stroke prevention with atorvastatin in the Collaborative Atorvastatin Diabetes Study (CARDS).

AIMS: Patients with Type 2 diabetes have an elevated risk of stroke. The role of lipid levels and diabetes-specific factors in risk prediction of stroke is unclear, and estimates of efficacy of lipid-lowering therapy vary between trials. We examined predictors of stroke and the effect of atorvastatin on specific stroke subtypes in Type 2 diabetes in the Collaborative Atorvastatin Diabetes Study (CARDS) [a trial of 2838 participants with mean low-density lipoprotein cholesterol < 4.14 mmol/l, no history of macrovascular disease and randomized to atorvastatin 10 mg daily or placebo]. METHODS: Median follow-up was 3.9 years. Cox regression models were used to estimate the effect of atorvastatin on stroke rate and risk of stroke associated with baseline risk factors. Risk factors that predicted stroke in univariate models were examined in a multivariable model. RESULTS: Independent risk factors predicting stroke were age [10-year increments; hazard ratio (HR) 2.3, P < 0.001], microalbuminuria (albumin : creatinine ratio > 2.5 mg/mmol; HR 2.0, P = 0.007) and glycaemic control (HbA(1c) > 10%; HR 2.7, P = 0.007). Women were at lower risk of stroke (HR 0.3, P = 0.004). Lipids did not predict stroke. Of 60 first strokes, 47 were non-haemorrhagic, 13 were indeterminate and none was definitely haemorrhagic. Atorvastatin treatment was associated with 50% reduction in non-haemorrhagic stroke (95% confidence interval 9%-72%P = 0.024), similar to the 48% reduction (11%-69%) for all strokes combined. CONCLUSIONS: Diabetes-specific risk factors are important predictors of stroke in Type 2 diabetes. Despite the lack of association between baseline lipids and first stroke, there was a reduction of 50% of non-haemorrhagic strokes associated with atorvastatin treatment in the CARDS population.

Thiazolidinedione increases serum soluble receptor for advanced glycation end-products in type 2 diabetes.

AIMS/HYPOTHESIS: Interfering with the activation of receptor for AGE (RAGE) by using a soluble form of the AGE receptor (sRAGE) prevents or ameliorates the vascular complications of diabetes in experimental studies. Relatively little is known about factors that influence endogenous circulating sRAGE in humans. We investigated the impact of improving glycaemic control on serum total sRAGE and endogenous secretory RAGE (esRAGE), a splice variant of sRAGE, and compared the effect of rosiglitazone with that of sulfonylurea. METHODS: A randomised, open-label, parallel group study was performed with 64 participants randomised to receive add-on therapy with either rosiglitazone or sulfonylurea. Serum total sRAGE and esRAGE and metabolic parameters were measured before and after 6 months of treatment. RESULTS: At 6 months, both rosiglitazone and sulfonylurea resulted in a significant reduction in HbA(1c), fasting glucose and AGE. However, significant increases in total sRAGE and esRAGE were only seen in the rosiglitazone group. As a result, serum esRAGE was higher in the rosiglitazone group than in the sulfonylurea group at 6 months (p < 0.01), whereas the differences in sRAGE between the two groups did not reach statistical significance. Stepwise linear regression analysis showed that treatment modality made a greater contribution than the changes in HbA(1c) to the subsequent changes in esRAGE levels at 6 months. CONCLUSIONS/INTERPRETATION: Treating type 2 diabetic patients with thiazolidinedione can increase circulating levels of esRAGE and sRAGE. Whether modulation of circulating sRAGE has a beneficial effect on diabetic complications will have to be evaluated in long-term prospective studies.

Effects of rosuvastatin on lipids, lipoproteins and apolipoproteins in the dyslipidaemia of diabetes.

AIMS: To compare the effects of rosuvastatin and atorvastatin 10 and 20 mg on plasma lipid and lipoprotein profiles in patients with Type 2 diabetes mellitus and triglycerides < or = 6.0 mmol/l. METHODS: A double-blind, randomized, multicentre study to assess the effect of rosuvastatin and atorvastatin, at 10 mg/day for 8 weeks followed by 20 mg/day for a further 8 weeks, on low-density lipoprotein cholesterol (LDL-C), together with a range of secondary lipid and lipoprotein end points. RESULTS: Rosuvastatin reduced mean LDL-C levels from baseline over 16 weeks by 57.4%, while atorvastatin reduced mean LDL-C levels by 46.0% over the same period. The difference in LDL-C reduction between treatments was statistically significant (P < 0.001). Rosuvastatin also produced statistically significantly greater mean reductions from baseline in levels of total cholesterol, non-high-density lipoprotein cholesterol, apolipoprotein B and lipid ratios. More patients achieved European LDL-C (< 2.5 mmol/l) and total cholesterol (< 4.5 mmol/l) goals with rosuvastatin than with atorvastatin. Rosuvastatin was associated with a significantly (P < 0.049) greater mean percentage increase in glycated haemoglobin (HbA(1c)) from baseline compared with atorvastatin; however, patients in both treatment groups maintained good glycaemic control. Both rosuvastatin and atorvastatin were well tolerated. CONCLUSIONS: Greater reductions in LDL-C were achieved with rosuvastatin compared with equal doses of atorvastatin, enabling more patients with Type 2 diabetes to achieve European LDL-C goals.

Cost-effectiveness of primary prevention of cardiovascular disease with atorvastatin in type 2 diabetes: results from the Collaborative Atorvastatin Diabetes Study (CARDS).

AIMS/HYPOTHESIS: We estimated the cost-effectiveness of atorvastatin treatment in the primary prevention of cardiovascular disease in patients with type 2 diabetes using data from the Collaborative Atorvastatin Diabetes Study (CARDS). SUBJECTS AND METHODS: A total of 2,838 patients, who were aged 40 to 75 years and had type 2 diabetes without a documented history of cardiovascular disease and without elevated LDL-cholesterol, were recruited from 32 centres in the UK and Ireland and randomly allocated to atorvastatin 10 mg daily (n = 1,428) or placebo (n = 1,410). These subjects were followed-up for a median period of 3.9 years. Direct treatment costs and effectiveness were analysed to provide estimates of cost per endpoint-free year over the trial period for alternative definitions of endpoint, and of cost per life-year gained and cost per quality-adjusted life-year (QALY) gained over a patient's lifetime. RESULTS: Over the trial period, the incremental cost-effectiveness ratio (ICER) was estimated to be 7,608 pounds per year free of any CARDS primary endpoint; the ICER was calculated to be 4,896 pounds per year free of any cardiovascular endpoint and 4,120 pounds per year free of any study endpoint. Over lifetime, the incremental cost per life-year gained was 5,107 pounds and the cost per QALY was 6,471 pounds (costs and benefits both discounted at 3.5%). CONCLUSIONS/INTERPRETATION: Primary prevention of cardiovascular disease with atorvastatin is a cost-effective intervention in patients with type 2 diabetes, with the ICER for this intervention falling within the current acceptance threshold ( 20,000 pounds per QALY) specified by the National Institute for Health and Clinical Excellence (NICE).

Genetic causes of familial hypercholesterolaemia in patients in the UK: relation to plasma lipid levels and coronary heart disease risk.

AIMS: To determine the relative frequency of mutations in three different genes (low-density lipoprotein receptor (LDLR), APOB, PCSK9), and to examine their effect in development of coronary heart disease (CHD) in patients with clinically defined definite familial hypercholesterolaemia in UK. PATIENTS AND METHODS: 409 patients with familial hypercholesterolaemia patients (158 with CHD) were studied. The LDLR was partially screened by single-strand conformational polymorphism (SSCP) (exons 3, 4, 6-10 and 14) and by using a commercial kit for gross deletions or rearrangements. APOB (p.R3500Q) and PCSK9 (p.D374Y) were detected by specific assays. Coding exons of PCSK9 were screened by SSCP. RESULTS: Mutations were detected in 253 (61.9%) PATIENTS: 236 (57.7%) carried LDLR, 10 (2.4%) carried APOB p.Q3500 and 7 (1.7%) PCSK9 p.Y374. No additional mutations were identified in PCSK9. After adjusting for age, sex, smoking and systolic blood pressure, compared to those with no detectable mutation, the odds ratio of having CHD in those with an LDLR mutation was 1.84 (95% CI 1.10 to 3.06), for APOB 3.40 (0.71 to 16.36), and for PCSK9 19.96 (1.88 to 211.5; p = 0.001 overall). The high risk in patients carrying LDLR and PCSK9 p.Y374 was partly explained by their higher pretreatment cholesterol levels (LDLR, PCSK9 and no mutation, 10.29 (1.85), 13.12 and 9.85 (1.90) mmol/l, respectively, p = 0.001). The post-statin treatment lipid profile in PCSK9 p.Y374 carriers was worse than in patients with no identified mutation (LDL-C, 6.77 (1.82) mmol/l v 4.19 (1.26) mmol/l, p = 0.001, HDL-C 1.09 (0.27) mmol/l v 1.36 (0.36) mmol/l, p = 0.03). CONCLUSIONS: The higher CHD risk in patients carrying PCSK9 p.Y347 or a detected LDLR mutation supports the usefulness of DNA testing in the diagnosis and management of patients with familial hypercholesterolaemia. Mutations in PCSK9 appear uncommon in patients with familial hypercholesterolaemia in UK.

Association between serum levels of soluble receptor for advanced glycation end products and circulating advanced glycation end products in type 2 diabetes.

AIMS/HYPOTHESIS: Activation of the receptor for advanced glycation end products (RAGE, also known as AGE-specific receptor [AGER]) has been implicated in the development of diabetic vascular complications. Blockade of RAGE using a soluble form of the receptor (sRAGE) suppressed vascular hyperpermeability and atherosclerosis in animal models. Since little is known about the regulation of endogenous sRAGE levels, we determined whether serum sRAGE is influenced by circulating AGEs and the severity of nephropathy in type 2 diabetic patients. MATERIALS AND METHODS: We recruited 150 healthy control and 318 diabetic subjects. Diabetic subjects were subdivided into those with proteinuria, microalbuminuria or normoalbuminuria. Serum sRAGE was assayed by ELISA and serum AGEs by competitive ELISA using a polyclonal rabbit antiserum raised against AGE-RNase. RESULTS: Diabetic subjects had higher sRAGE (1,029.5 pg/ml [766.1-1,423.0] interquartile range vs 1,002.6 [726.5-1,345.3], p<0.05) and AGEs (4.07+/-1.13, SD, unit/ml vs 3.39+/-1.05, p<0.01) than controls. Proteinuric subjects had the highest sRAGE levels and there was a significant trend between the severity of nephropathy and sRAGE (p=0.01). In diabetic subjects, serum log(sRAGE) correlated with AGEs (r=0.27, p<0.001), log(plasma creatinine) (r=0.31, p<0.001), log(urine AER) (r=0.24, p<0.01) and log(triglycerides) (r=0.15, p<0.01). On stepwise linear regression analysis, AGEs and creatinine levels were the main independent determinants of sRAGE concentration. CONCLUSIONS/INTERPRETATION: Serum sRAGE levels and circulating AGEs are associated with the severity of nephropathy in type 2 diabetic patients. Prospective studies are required to determine whether endogenous sRAGE potentially influences the development of diabetic vascular complications.

The effect of sensitisation to insulin with pioglitazone on fasting and postprandial lipid metabolism, lipoprotein modification by lipases, and lipid transfer activities in type 2 diabetic patients.

AIMS/HYPOTHESIS: Insulin resistance is thought to be central to the pathogenesis of diabetic dyslipidaemia. We hypothesised that improving insulin sensitivity would improve fasting and postprandial triglyceride metabolism in patients with type 2 diabetes. To this aim we studied fasting and postprandial lipaemia in type 2 diabetic patients before and after sensitisation to insulin with pioglitazone, compared with that observed in patients on an insulin-providing regime. METHODS: In a double-blind placebo-controlled protocol, 22 patients with type 2 diabetes were randomly allocated to receive either pioglitazone (45 mg/day) or glibenclamide (5 mg/day), for a 20-week period. Fasting and postprandial lipid metabolism were investigated at baseline and at the end of the treatment period. A group of non-diabetic subjects was also studied. RESULTS: Compared with glibenclamide treatment, pioglitazone treatment decreased fasting triglyceride, glucose and insulin levels and the homeostasis model assessment score of insulin resistance. Decreased fasting triglyceride after pioglitazone treatment was due to reduced VLDL triglyceride, particularly VLDL-2. Lipoprotein lipase activity was unchanged by pioglitazone treatment but hepatic lipase showed a significant decrease. Pioglitazone treatment lowered total postprandial triglyceride, as well as chylomicron- and chylomicron-remnant retinyl palmitate levels to normal. Glucose disposal improved but remained abnormal. CONCLUSIONS/INTERPRETATION: Insulin sensitisation with pioglitazone has major effects in restoring postprandial lipaemia to normal, while also correcting fasting hypertriglyceridaemia; both factors may have consequences for atherogenic risk in diabetes.

Rapid emergence of effect of atorvastatin on cardiovascular outcomes in the Collaborative Atorvastatin Diabetes Study (CARDS).

AIMS/HYPOTHESIS: The aim of this study was to determine the pattern of the effect of the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor atorvastatin on cardiovascular events in patients with type 2 diabetes and no prior history of cardiovascular disease (CVD). MATERIALS AND METHODS: A post hoc analysis of data from the Collaborative Atorvastatin Diabetes Study (CARDS), a randomised, placebo-controlled trial of 2,838 patients with type 2 diabetes, was performed. Patients received atorvastatin (10 mg daily) or placebo and were evaluated for cardiovascular and other outcomes over a median follow-up period of 3.9 years. Cox proportional hazards modelling was carried out, and the hazard ratios calculated for various times after randomisation to treatment were investigated. RESULTS: A reduction in the primary endpoint of major CVD events was apparent and statistically significant as soon as 18 months after treatment initiation. The effect of atorvastatin on CHD events was apparent by 6 months, and at 1 year was similar to the 37% relative risk reduction observed at trial closure. CONCLUSIONS/INTERPRETATION: Atorvastatin alters the pathogenesis of CVD rapidly, such that the effect on cardiovascular events is apparent within months of initiation of therapy.

Long-term effects on lipids and lipoproteins of pioglitazone versus gliclazide addition to metformin and pioglitazone versus metformin addition to sulphonylurea in the treatment of type 2 diabetes.

AIMS/HYPOTHESIS: The aim of this study was to determine the long-term effects of pioglitazone add-on to metformin or sulphonylurea on plasma lipids and lipoproteins. MATERIALS AND METHODS: The effects of pioglitazone were studied in two clinical trials in patients with inadequately controlled type 2 diabetes (HbA1c > or =7.5 and < or =11%). In the first trial, patients currently receiving metformin were randomised to pioglitazone (15-45 mg/day, n=317) or gliclazide (80-320 mg/day, n=313) add-on therapy. In the second study, pioglitazone (15-45 mg/day, n=319) or metformin (850-2,550 mg/day, n=320) was added to sulphonylurea therapy. Patients were force-titrated to the maximum tolerated dose of add-on therapy, which was maintained to the 2-year endpoint. RESULTS: There were no statistically significant differences between the groups with respect to HbA1c reduction from baseline to week 104. Whether added to metformin or sulphonylurea, pioglitazone caused highly significant greater decreases in triglycerides and increases in HDL cholesterol from baseline to week 104 than treatments with gliclazide or metformin add-on therapies (p< or =0.001). The triglyceride reductions noted with pioglitazone were maintained over time, with decreases of 16-18% at 1 year and 17-23% at 2 years. In the pioglitazone groups, the improvement in HDL cholesterol at 1 year was maintained, with 21-22% augmentations at 2 years (p<0.001 between-group difference). Small but statistically significant greater reductions in LDL cholesterol were observed with gliclazide vs pioglitazone add-on to metformin and metformin vs pioglitazone add-on to sulphonylurea (p<0.001 for between-group difference). In the pioglitazone groups, mean LDL cholesterol at 2 years was similar to mean baseline LDL cholesterol. CONCLUSIONS/INTERPRETATION: After 2 years, highly significant decreases in triglycerides and increases in HDL cholesterol that were sustained over time or even improved were observed when pioglitazone was added to metformin or sulphonylurea therapy. These effects of pioglitazone on lipids may be potentially beneficial in reducing cardiovascular risk in type 2 diabetes.