Novel therapeutics for type 2 diabetes: insulin resistance.

Insulin resistance (IR) plays an important role in the pathogenesis of type 2 diabetes (T2D) and cardiovascular disease. Hence improving IR is a major target of treatment in patients with T2D. Obesity and lack of exercise are major causes of IR. However, recent evidence implicates sleep disorders and disorders of the circadian rhythm in the pathogenesis of IR. Weight loss and lifestyle changes are the cornerstone and most effective treatments of IR, but adherence and patient's acceptability are poor. Bariatric surgery results in significant and sustainable long-term weight loss associated with beneficial impact on IR and glucose metabolism, making this an attractive treatment option for patients with T2D. Currently available pharmacological options targeting IR (such as metformin and thiazolidinediones) do not maintain glycaemic measures within targets long term and can be associated with significant side effects. Over the last two decades, many pharmacological agents targeting different aspects of the insulin signalling pathway were developed to improve IR, but only a minority reached clinical trials. Such treatments need to be specific and reversible as many of the components of the insulin signalling pathway are involved in other cellular functions such as apoptosis. Recent evidence highlighted the role of circadian rhythm and sleep-related disorders in the pathogenesis of IR. In this article, we review the latest developments in the pharmacological and non-pharmacological interventions targeting IR including bariatric surgery. We will also review the role of circadian rhythm and sleep-related disorders in the development and treatment of IR.

What factors influence concordance with medications? Findings from the U.K. Asian Diabetes study.

AIMS: To investigate concordance with medication, as assessed at baseline and at 1- and 2-year follow-up, and to examine factors associated with non-concordance in a UK-resident South-Asian population. METHODS: Data from the UK Asian Diabetes Study were analysed. Concordance with medications was assessed and recorded at three time points during the study. Multiple logistic regression was used to investigate the factors associated with non-concordance; the associations of baseline factors with year 1 concordance and baseline plus year 1 factors with year 2 concordance. RESULTS: Data for 403 patients from seven practices participating in the UK Asian Diabetes Study were analysed. The numbers of patients who were non-concordant were: 63 (16%) at baseline; 101 (25%) at year 1; and 122 (30%) at year 2. The baseline-measured variables that were significantly associated with year 1 non-concordance included diabetes duration, history of cardiovascular disease, components of the EuroQol quality of life questionnaire, the EQ-5D score, and number of medications prescribed. In multivariable analyses, the most important determinant of year 1 non-concordance was baseline non-concordance: odds ratio 13.6 (95% confidence limits 4.7, 39.9). Number of medications prescribed for blood pressure control was also significant: odds ratio 1.8 (95% confidence limits 1.4, 2.4). Similar results were observed for year 2 non-concordance. CONCLUSIONS: Non-concordance with medications was common and more likely in people prescribed more medications. The current target-driven management of risk factor levels may lead to increasing numbers and doses of medications. Considering the high cost of medications and the implications of poor health behaviours on morbidity and mortality, further investigation of prescribing behaviours and the factors affecting patient concordance are required.

Dapagliflozin compared with other oral anti-diabetes treatments when added to metformin monotherapy: a systematic review and network meta-analysis.

AIMS: Indirect evidence from randomized controlled trials (RCTs) was used to estimate the effect of dapagliflozin, a new agent with a novel mechanism of action (SGLT-2 inhibition), relative to other anti-diabetes therapies after 1 year of treatment. METHODS: A systematic literature review and Bayesian network meta-analysis (NMA) of RCTs involving anti-diabetes treatments added to metformin were conducted. RCTs enrolling subjects with type 2 diabetes inadequately controlled on metformin monotherapy were included. Comparators included dipeptidyl peptidase-4 (DPP-4) inhibitors, thiazolidinediones (TZDs), sulphonylureas, glucagon-like peptide-1 (GLP-1) analogues and dapagliflozin. Outcomes of interest were mean change from baseline HbA1c, weight and systolic blood pressure, and incidence of hypoglycaemia. RESULTS: From 4270 abstracts, six RCTs were included in the primary analysis; no RCTs involving GLP-1 analogues met primary inclusion criteria. All RCTs were actively controlled with sulphonylureas. The mean change in HbA1c from baseline was similar across comparators. The treatment effect (95% credible interval) of dapagliflozin on HbA1c was -0.08% (-0.25, 0.10) relative to DPP-4 inhibitors, -0.02% (-0.24, 0.21) relative to TZDs and 0.00% (-0.16, 0.16) relative to sulphonylureas. Non-sulphonylureas showed significantly lower risk of hypoglycaemia relative to sulphonylureas. Dapagliflozin had a significant effect on weight change: the relative difference was -2.74 kg (-5.35, -0.10) compared with DPP-4 inhibitors, and -4.67 kg (-7.03, -2.35) compared with sulphonylureas. Systolic blood pressure was not meta-analysed due to infrequent reporting. CONCLUSION: Compared with DPP-4 inhibitors, TZDs and sulphonylureas, dapagliflozin offers similar HbA1c control after 1 year, with similar or reduced risk of hypoglycaemia and the additional benefit of weight loss, when added to metformin.

Safety and efficacy of the dipeptidyl peptidase-4 inhibitor linagliptin in elderly patients with type 2 diabetes: a comprehensive analysis of data from 1331 individuals aged ≥ 65 years.

AIMS: To investigate individual patient data from a comprehensive trials programme to evaluate the safety and efficacy of the dipeptidyl peptidase-4 (DPP-4) inhibitor linagliptin across a range of glucose-lowering regimens in a large elderly population with type 2 diabetes mellitus (T2DM). METHODS: Data were pooled from individuals aged ≥ 65 years, who participated in seven phase III, placebo-controlled clinical trials of linagliptin (24-52 weeks). Safety was assessed by incidence and severity of adverse events (AEs) with a focus on hypoglycaemia. The primary efficacy endpoint was change in glycated haemoglobin (HbA1c). RESULTS: In total, 841 subjects received linagliptin 5 mg once a day and 490 received placebo. At baseline, the population had a mean ± s.d. age of 71.0 ± 4.6 years and a mean HbA1c concentration of 8.0 ± 0.8%; 63.5% of subjects received ≥ 2 antidiabetes drugs. Overall AEs and drug-related AEs were experienced by similar proportions of patients (linagliptin 71.3, placebo 73.3; linagliptin 18.1, placebo 19.8%, respectively). The incidence of investigator-reported hypoglycaemia was 21.4% with linagliptin and 25.7% with placebo. Severe hypoglycaemic events were rare and there were fewer in the linagliptin group (1.0 vs. 1.8%). At week 24, the placebo-corrected adjusted mean ± s.e. reduction in HbA1c with linagliptin was -0.62 ± 0.06% (95% CI: -0.73, -0.51). CONCLUSIONS: Data from this large cohort show that linagliptin is a well-tolerated and efficacious therapy for elderly patients with T2DM. Treatment with linagliptin may support individualized treatment goals, while effectively managing the risk of hypoglycaemia or drug-related side effects.

Incidence, worry and discussion about dosing irregularities and self-treated hypoglycaemia amongst HCPs and patients with type 2 diabetes: results from the UK cohort of the Global Attitudes of Patient and Physicians (GAPP2) survey.

AIMS: The Global Attitude of Patients and Physicians 2 (GAPP2) survey sought to address gaps in understanding about real-world basal insulin-taking behaviour and self-treated hypoglycaemia in patients with type 2 diabetes mellitus. MATERIALS AND METHODS: The Global Attitude of Patients and Physicians 2 was an international, online, cross-sectional study of patients aged at least 40 years with type 2 diabetes taking analogue insulins, and healthcare professionals (HCPs). Patients were recruited from general consumer online research panels, comprising a representative sample of the population to minimise bias. HCPs were recruited from online specialist research panels. The results of the UK cohort are presented here. RESULTS: The UK cohort constituted 12% of the total GAPP2 population. In this cohort, 15-25% of patients reported that they had reduced, missed or mistimed at least one dose of insulin in the previous month. On the last occasion that patients had reduced a dose, 82% had done so intentionally - most frequently because of concerns about hypoglycaemia. HCP estimates of the numbers of patients with dosing irregularities were nearly fourfold higher than patient reports. More than one-third of HCPs believe their patients under-report the frequency of self-treated hypoglycaemia. Nevertheless, a proportion did not regularly discuss these concerns with their patients. CONCLUSIONS: Healthcare professionals are in the best position to support patients in making appropriate insulin dose adjustments to help regularise blood glucose levels and reduce treatment-induced hypoglycaemic events. This can be achieved by initiating frequent discussions with all patients and providing education and training when appropriate.

Combination therapy with GLP-1 receptor agonists and basal insulin: a systematic review of the literature.

Treatment algorithms for type 2 diabetes call for intensification of therapy over time as the disease progresses and glycaemic control worsens. If diet, exercise and oral antihyperglycaemic medications (OAMs) fail to maintain glycaemic control then basal insulin is added and ultimately prandial insulin may be required. However, such an intensification strategy carries risk of increased hypoglycaemia and weight gain, both of which are associated with worse long-term outcomes. An alternative strategy is to intensify therapy by the addition of a short-acting glucagon-like peptide-1 receptor agonist (GLP-1 RA) rather than prandial insulin. Short-acting GLP-1 RAs such as exenatide twice daily are particularly effective at reducing postprandial glucose while basal insulin has a greater effect on fasting glucose, providing a physiological rationale for this complementary approach. This review analyzes the latest randomized controlled clinical trials of insulin/GLP-1 RA combination therapy and examines results from 'real-world' use of the combinations as reported through observational and clinical practice studies. The most common finding across all types of studies was that combination therapy improved glycaemic control without weight gain or an increased risk of hypoglycaemia. Many studies reported weight loss and a reduction in insulin use when a GLP-1 RA was added to existing insulin therapy. Overall, the relative degree of benefit to glycaemic control and weight was influenced by the insulin titration employed in conjunction with the GLP-1 RA. The greatest glycaemic benefits were observed in studies with structured titration of insulin to glycaemic targets while the greatest weight benefits were observed in studies with a protocol-specified focus on insulin sparing. The adverse event profile of GLP-1 RAs in the reviewed trials was similar to that reported with GLP-1 RAs as monotherapy or in combination with OAMs with gastrointestinal events being the most commonly reported.

The incidence of type 2 diabetes in the United Kingdom from 1991 to 2010.

AIMS: To characterize the incidence of type 2 diabetes in the UK over the previous 20 years; and determine if there has been an increase in people aged 40 years or less at diagnosis. METHODS: For this retrospective cohort study, patients newly diagnosed with type 2 diabetes between 1991 and 2010 were identified from the UK Clinical Practice Research Datalink (CPRD). Patient data were grouped into 5-year intervals by year of diagnosis and age at diagnosis. A standardized incidence ratio (SIR) was determined (1991-1995 = 100). The percentage of newly diagnosed patients for each age group and aged ≤40 years was calculated for each 5-year calendar period. The incidence rate by age and 5-year calendar period was also determined. RESULTS: In 2010, the crude incidence rate of type 2 diabetes was 515 per 100,000 population. The overall SIR increased to 158 (95% CI 157-160, p < 0.001), 237 (235-238, p < 0.001) and 275 (273-276, p < 0.001) for 1996-2000, 2001-2005 and 2006-2010, respectively. For those ≤40, the respective values were 217 (209-226, p < 0.001), 327 (320-335, p < 0.001) and 598 (589-608, p < 0.001). An increase in incidence occurred with increasing 5-year calendar period. The incidence of type 2 diabetes was higher for males after the age of 40 and higher for females aged ≤40. The percentage of patients aged ≤40 years at diagnosis increased with each increasing 5-year calendar period (5.9, 8.4, 8.5 and 12.4%, respectively). CONCLUSIONS: There was a significant increase in the incidence of diagnosed type 2 diabetes between 1991 and 2010 and the proportion of people diagnosed at a relatively early age has increased markedly.

Effectiveness and tolerability of second-line therapy with vildagliptin vs. other oral agents in type 2 diabetes: a real-life worldwide observational study (EDGE).

AIM: Real-life studies are needed to confirm the clinical relevance of findings from randomised controlled trials (RCTs). This study aimed to assess the effectiveness and tolerability of vildagliptin add-on vs. other oral antihyperglycaemic drugs (OADs) added to OAD monotherapy in a real-life setting, and to explore the advantages and limitations of large-scale 'pragmatic' trials. METHODS: EDGE was a prospective, 1-year, worldwide, real-life observational study in which 2957 physicians reported on the effects of second-line OADs in 45,868 patients with T2DM not reaching glycaemic targets with monotherapy. Physicians could add any OAD, and patients entered either vildagliptin or (pooled) comparator cohort. The primary effectiveness and tolerability end-point (PEP) evaluated proportions of patients decreasing HbA(1c) > 0.3%, without hypoglycaemia, weight gain, peripheral oedema or gastrointestinal side effects. The most clinically relevant secondary end-point (SEP 3) was attainment of end-point HbA(1c) < 7% without hypoglycaemia or ≥ 3% increase in body weight. RESULTS: In this large group of T2DM patients, a second OAD was added at mean HbA(1c) of 8.2 ± 1.3%, with no baseline HbA(1c) difference between cohorts. Second-line OAD therapy attained the PEP in the majority of patients, with higher attainment in those prescribed a vildagliptin-based regimen. The adjusted odds ratio was 1.49 (95% CI: 1.42, 1.55; p < 0.001). In patients with baseline HbA(1c) ≥ 7%, SEP 3 was achieved by 35% of patients on a vildagliptin-based combination and by 23% of those receiving comparator combinations. The adjusted odds ratio was 1.96 (95% CI: 1.85, 2.07; p < 0.001). Safety events were reported infrequently and safety profiles of vildagliptin and other OADs were consistent with previous data. CONCLUSION: EDGE demonstrates that in a 'real-life' setting, vildagliptin as second OAD can lower HbA(1c) to target without well-recognised OAD side effects, more frequently than comparator OADs. In addition, EDGE illustrates that conducting large-scale, prospective, real-life studies poses challenges but yields valuable clinical information complementary to RCTs.

A search for type 1 diabetes susceptibility genes in families from the United Kingdom.

Genetic analysis of a mouse model of major histocompatability complex (MHC)-associated autoimmune type 1 (insulin-dependent) diabetes mellitus (IDDM) has shown that the disease is caused by a combination of a major effect at the MHC and at least ten other susceptibility loci elsewhere in the genome. A genome-wide scan of 93 affected sibpair families (ASP) from the UK (UK93) indicated a similar genetic basis for human type 1 diabetes, with the major genetic component at the MHC locus (IDDM1) explaining 34% of the familial clustering of the disease (lambda(s)=2.5; refs 3,4). In the present report, we have analysed a further 263 multiplex families from the same population (UK263) to provide a total UK data set of 356 ASP families (UK356). Only four regions of the genome outside IDDM1/MHC, which was still the only major locus detected, were not excluded at lambda(s)=3 and lod=-2, of which two showed evidence of linkage: chromosome 10p13-p11 (maximum lod score (MLS)=4.7, P=3x10(-6), lambda(s)=1.56) and chromosome 16q22-16q24 (MLS=3.4, P=6.5x10(-5), lambda(s)=1.6). These and other novel regions, including chromosome 14q12-q21 and chromosome 19p13-19q13, could potentially harbour disease loci but confirmation and fine mapping cannot be pursued effectively using conventional linkage analysis. Instead, more powerful linkage disequilibrium-based and haplotype mapping approaches must be used; such data is already emerging for several type 1 diabetes loci detected initially by linkage.

Measuring psychological well-being in South Asians with diabetes; a qualitative investigation of the PHQ-9 and the WHO-5 as potential screening tools for measuring symptoms of depression.

BACKGROUND: People from South Asian backgrounds living in the UK have a greatly increased risk of developing Type 2 diabetes. Whether or not this patient group also experience high rates of depressive symptoms (known to be the case in Caucasian populations with diabetes) remains unknown, partly because it is unclear whether the screening tools used are culturally relevant. The aim of this study was to develop culturally competent translations (in both written and audio formats) of two screening tools used to measure symptoms of depression in languages with no written form and establish their face validity. METHODS: Adults with Type 2 diabetes from two South Asian minority ethnic groups (from Bangladesh and Pakistan) whose main language is only spoken (Sylheti and Mirpuri) were recruited via the Birmingham Heartlands Hospital Diabetes Centre. Participants attended two focus group meetings to consider the content and method of delivery of two questionnaires measuring symptoms of depression, the Patient Health Questionnaire (PHQ-9) and the World Health Organization Well-being Index (WHO-5). RESULTS: Culturally equivalent content was achieved for both questionnaires in both languages. The Mirpuri men and women groups did not indicate a clear preference for either mode of questionnaire delivery; however, the Sylheti groups' preference was for independent audio-delivery in their spoken language. CONCLUSIONS: The face validity of the PHQ-9 and the WHO-5 was established for Sylheti and Mirpuri in an audio delivery format. Psychometric testing is now needed among minority ethnic populations so that the feasibility of wider use can be determined.

Insulin adherence behaviours and barriers in the multinational Global Attitudes of Patients and Physicians in Insulin Therapy study.

AIMS: To examine patient and physician beliefs regarding insulin therapy and the degree to which patients adhere to their insulin regimens. METHODS: Internet survey of 1250 physicians (600 specialists, 650 primary care physicians) who treat patients with diabetes and telephone survey of 1530 insulin-treated patients (180 with Type 1 diabetes, 1350 with Type 2 diabetes) in China, France, Japan, Germany, Spain, Turkey, the UK or the USA. RESULTS: One third (33.2%) of patients reported insulin omission/non-adherence at least 1 day in the last month, with an average of 3.3 days. Three quarters (72.5%) of physicians report that their typical patient does not take their insulin as prescribed, with a mean of 4.3 days per month of basal insulin omission/non-adherence and 5.7 days per month of prandial insulin omission/non-adherence. Patients and providers indicated the same five most common reasons for insulin omission/non-adherence: too busy; travelling; skipped meals; stress/emotional problems; public embarrassment. Physicians reported low patient success at initiating insulin in a timely fashion and adjusting insulin doses. Most physicians report that many insulin-treated patients do not have adequate glucose control (87.6%) and that they would treat more aggressively if not for concern about hypoglycaemia (75.5%). Although a majority of patients (and physicians) regard insulin treatment as restrictive, more patients see insulin treatment as having positive than negative impacts on their lives. CONCLUSIONS: Glucose control is inadequate among insulin-treated patients, in part attributable to insulin omission/non-adherence and lack of dose adjustment. There is a need for insulin regimens that are less restrictive and burdensome with lower risk of hypoglycaemia.

The role of GLP-1 mimetics and basal insulin analogues in type 2 diabetes mellitus: guidance from studies of liraglutide.

In people with type 2 diabetes mellitus (T2DM), the incretin effect is reduced, but the recent advent of dipeptidyl peptidase-4 inhibitors and glucagon-like peptide (GLP)-1 agonists/analogues has enabled restoration of at least some of the function of the incretin system, with accompanying improvements in glycaemic control. Two GLP-1 receptor agonists/analogues are currently approved for the treatment of T2DM-exenatide (Byetta®, Eli Lilly & Co., Indianapolis, IN, US) and liraglutide (Victoza®, Novo Nordisk, Bagsvaerd, Denmark); a once-weekly formulation of exenatide (Bydureon®, Eli Lilly & Co.) has also been approved by the European Medicines Agency. The National Institute for Health and Clinical Excellence (NICE) has recently published guidance on the use of liraglutide in T2DM, based on evidence from the Liraglutide Effect and Action in Diabetes (LEAD) Phase III trial programme, which compared liraglutide with existing glucose-lowering therapies, such as exenatide and insulin glargine. The LEAD programme reported HbA1c reductions from 0.8 to 1.5% with liraglutide (1.2 and 1.8 mg), accompanied by low rates of hypoglycaemia and some weight loss; side effects were primarily gastrointestinal in nature (e.g. nausea and diarrhoea). Based on the findings of the LEAD studies and the NICE recommendation, liraglutide now represents an important therapy widely available in the UK for certain patient groups, including those with a body mass index (BMI) ≥35.0 kg/m(2) , and patients with a BMI <35 kg/m(2) who are considered unsuitable for insulin and are failing to meet targets for glycaemic control with oral agents. NICE guidelines still suggest that most patients without considerable obesity (BMI <35 kg/m(2) ) are probably best managed using insulin therapy. Evidence also suggests a future role for GLP-1 mimetics in combination with basal insulin.

Factors associated with injection omission/non-adherence in the Global Attitudes of Patients and Physicians in Insulin Therapy study.

AIM: To examine factors associated with insulin injection omission/non-adherence on a global basis. METHODS: Telephone survey of 1530 insulin-treated adults with self-reported diabetes (110 type 1 and 1420 type 2) in China, France, Japan, Germany, Spain, Turkey, UK or USA. Participants had a mean age of ∼60 years, ∼15 years duration of diabetes and ∼9 years duration of insulin treatment. Regression analysis assessed the independent associations (p < 0.05) of country, participant characteristics and treatment-related beliefs/perceptions with number of days in the past month that an insulin injection was missed or not taken as prescribed. RESULTS: One third (35%) of respondents reported one or more days (mean: ∼3 days) of insulin omission/non-adherence. Insulin omission/non-adherence differed widely across countries (range = 20-44%); differences in days of insulin omission/non-adherence were maintained after adjustment for other risk factors. Most risk factors had similar relationships with insulin omission/non-adherence across countries (few interactions with country). Insulin omission/non-adherence was more frequent among respondents who were male, younger, had type 2 diabetes or more frequent hypoglycaemia, were less successful with other treatment tasks, regarded insulin adherence as less important, had more practical/logistical barriers and difficulties with insulin adherence, were concerned that insulin treatment required lifestyle changes or were dissatisfied with the flexibility of injection timing. CONCLUSIONS: The results of this large-scale study suggest that insulin omission/non-adherence is common and associated with several modifiable risk factors (including practical barriers, injection difficulties, lifestyle burden and regimen inflexibility). Additional efforts to address these risk factors might reduce the frequency of insulin omission/non-adherence and lead to improved clinical outcomes.

Weight change in people with type 2 diabetes: secular trends and the impact of alternative antihyperglycaemic drugs.

AIM: This study aimed to describe the pattern of weight change in people with type 2 diabetes (T2DM) over time and when using alternative treatment regimens. METHODS: Data were from routine clinical practice in the UK. The weight trend was determined for each year from 1995 to 2010 for both prevalent and incident cases. Baseline weight was compared to absolute (mean Δ) and relative weights (% Δ) at 6, 12 and 24 months. RESULTS: Mean, standardized weight in prevalent cases increased from 83.4 to 92.1 kg for males and from 73.5 to 79.9 kg for females between 1995 and 2010 (p < 0.0001). For incident cases, the respective figures were 86.7 to 93.6 kg for males and 76.0 to 80.7 kg for females (p < 0.001). Between baseline and 6, 12 and 24 months, there were significant changes in weight for the majority of the treatment regimens selected for analysis. The largest weight increase at 12 months was for the patients who were prescribed a combination therapy with insulin and a thiazolidinedione, with a median increase of 4.1 kg (95% CI -0.60 to 8.0, p < 0.001). The largest weight decrease at 12 months was for the patients who were prescribed a combination therapy of metformin and exenatide, with a median decrease of -7.0 kg (95% CI -12.0 to -2.0, p < 0.001). CONCLUSIONS: There was a continual increase in body weight in people with T2DM over time, and considerable differences in the impact on weight using alternative treatment regimens. At the same time, glycaemic control remained relatively unchanged.

Linagliptin monotherapy in type 2 diabetes patients for whom metformin is inappropriate: an 18-week randomized, double-blind, placebo-controlled phase III trial with a 34-week active-controlled extension.

AIMS: To investigate the efficacy and safety of linagliptin, a dipeptidyl peptidase-4 inhibitor, in type 2 diabetes mellitus (T2DM) patients for whom metformin was inappropriate. METHODS: This 1-year double-blind study (ClinicalTrials.gov, NCT00740051) enrolled T2DM patients with inadequate glycaemic control, treatment-naïve [glycated haemoglobin (HbA1c) 7.0-10.0%] or previously treated with one oral antidiabetes drug (HbA1c 6.5-9.0% before washout), ineligible for metformin because of contraindications (e.g. renal impairment) or previous intolerable side effects. Patients were randomized to monotherapy with linagliptin 5 mg once daily (n = 151) or placebo (n = 76) for 18 weeks, after which placebo patients switched to glimepiride 1-4 mg once daily and treatments continued for another 34 weeks. The primary endpoint was change from baseline in HbA1c after 18 weeks (full-analysis set, last observation carried forward). RESULTS: At week 18, adjusted mean difference in change from baseline HbA1c (8.1%) was -0.60% (95% confidence interval -0.88, -0.32; p < 0.0001) (-0.39% with linagliptin, +0.21% with placebo). At week 52, mean HbA1c was decreased from baseline in both groups [linagliptin: -0.44%; placebo/glimepiride: -0.72% (observed cases)]. Adverse events occurred in 40.4 and 48.7% of linagliptin and placebo patients, respectively, during the initial 18 weeks. During the 34-week extension, patients receiving linagliptin experienced less hypoglycaemia (2.2% vs. 7.8%) and no weight gain (mean change from baseline of -0.2 and +1.3 kg, respectively) compared with glimepiride patients. CONCLUSIONS: In T2DM patients for whom metformin was inappropriate, linagliptin improved glycaemic control and was well tolerated, with less hypoglycaemia and relative weight loss compared with glimepiride.

Safety and tolerability of linagliptin: a pooled analysis of data from randomized controlled trials in 3572 patients with type 2 diabetes mellitus.

AIMS: To assess the safety and tolerability of the dipeptidyl peptidase-4 inhibitor linagliptin in patients with type 2 diabetes. METHODS: Data were pooled from eight randomized, double-blind, placebo-controlled Phase III clinical trials lasting ≤24 weeks. Incidences were calculated with descriptive statistics for the overall population and for subgroups of elderly and renally impaired patients. RESULTS: A total of 2523 patients received linagliptin 5 mg once daily and 1049 patients received placebo. The overall incidence of adverse events (AEs) or serious AEs with linagliptin was similar to placebo (AEs 55.8% vs. 55.0%; serious AEs 2.8% vs. 2.7%). Overall aggregated infection incidence was 19.5% for linagliptin and 21.4% for placebo. Similar or reduced incidence of AEs versus placebo were seen with linagliptin for upper respiratory tract infection (3.3% vs. 4.9%), headache (2.9% vs. 3.1%), urinary tract infection (2.2% vs. 2.7%), blood and lymphatic disorders (1.0% vs. 1.2%), hypersensitivity (0.1% vs. 0.1%), hepatic enzyme increase (0.1% and 0.1%) and serum creatinine increase (0.0% and 0.1%). There was a slight increased frequency of nasopharyngitis (5.9% vs. 5.1%) and cough (1.7% vs. 1.0%) with linagliptin. Hypoglycaemia incidence was 8.2% for linagliptin and 5.1% for placebo; incidence was higher in patients with a background of sulphonylurea therapy (20.7% and 13.3%, respectively). In patients not receiving concomitant sulphonylurea, the hypoglycaemic incidence with linagliptin was very low in both the total population (<1%), and elderly and renally impaired patients (both <1%). CONCLUSIONS: This pooled analysis shows that linagliptin is well tolerated, with a low risk of hypoglycaemia.

Replication of 13 genome-wide association (GWA)-validated risk variants for type 2 diabetes in Pakistani populations.

AIMS/HYPOTHESIS: Recent genome-wide association (GWA) studies and subsequent replication studies have greatly increased the number of validated type 2 diabetes susceptibility variants, but most of these have been conducted in European populations. Despite the high prevalence of the disease in South Asians, studies investigating GWA-validated type 2 diabetes risk variants in this ethnic group are limited. We investigated 30 single nucleotide polymorphisms (SNPs), predominantly derived from recent GWA studies, to determine if and to what extent these variants affect type 2 diabetes risk in two Punjabi populations, originating predominantly from the District of Mirpur, Pakistan. METHODS: Thirty SNPs were genotyped in 1,678 participants with type 2 diabetes and 1,584 normoglycaemic control participants from two populations; one resident in the UK and one indigenous to the District of Mirpur. RESULTS: SNPs in or near PPARG, TCF7L2, FTO, CDKN2A/2B, HHEX/IDE, IGF2BP2, SLC30A8, KCNQ1, JAZF1, IRS1, KLF14, CHCHD9 and DUSP9 displayed significant (p < 0.05) associations with type 2 diabetes, with similar effect sizes to those seen in European populations. A constructed genetic risk score was associated with type 2 diabetes (p = 5.46 × 10(-12)), BMI (p = 2.25 × 10(-4)) and age at onset of diabetes (p = 0.002). CONCLUSIONS/INTERPRETATION: We have demonstrated that 13 variants confer an increased risk of type 2 diabetes in our Pakistani populations; to our knowledge this is the first time that SNPs in or near KCNQ1, JAZF1, IRS1, KLF14, CHCHD9 and DUSP9 have been significantly associated with the disease in South Asians. Large-scale studies and meta-analyses of South Asian populations are needed to further confirm the effect of these variants in this ethnic group.

Diabetes-science, serendipity and common sense.

This paper is dedicated to young researchers in diabetes. One such person was Frederick Banting who, with his colleagues, isolated insulin in 1921, saving the lives of literally millions of people. What factors allowed Banting and other scientists to produce work that has immensely benefited the human race? I propose that it is the combination of good scientific background (the 'prepared mind'), commonly some serendipity taken with a good dose of common sense and supplemented by enthusiasm, tenacity and good mentoring, which drives the 'power of observation' and the ability to take forward the good idea. I give examples from history to support this and then discuss some of the 'truths, perspectives and controversies' within the diabetes arena when I first started in diabetes research in the late 1970s. I describe how my appetite was initially 'whetted' for research by moving to an excellent clinical research environment with encouragement to test ideas and controversies initially in a clinical research programme, followed by more scientific/basic research. The work that I performed as a young doctor and research fellow led to a lifelong professional interest in three major areas-causes and interventions for diabetes vascular disease, studies of the molecular genetics of Type 1 and Type 2 diabetes and work on diabetes in different ethnic groups. I provide a summation of my own and other people's work to demonstrate how research can be progressed and lead to patient benefit as well as providing an incredibly rewarding career. I believe that we need to encourage and put more resources into development of young doctors and scientists wishing to undertake research in our discipline. Areas ripe for much-needed clinical research programmes, for example, include work on best practice/provision of health care, application of the evidence base from clinical trials to achieve public health gains, attention to adherence issues and better-tolerated therapies. Most importantly, a greater emphasis on prevention through public health measures and 'buy in' from the whole population is urgently required.

Modification and validation of the Revised Diabetes Knowledge Scale.

OBJECTIVES: To develop a simplified true/false response format of the Revised Diabetes Knowledge Scale and assess scaling assumptions, reliability and validity of the binary response format (the Simplified Diabetes Knowledge Scale) and compare with a multiple-choice version. METHODS: Ninety-nine respondents attending an outpatient clinic completed the multiple-choice version of the Revised Diabetes Knowledge Scale and the simplified version of the Revised Diabetes Knowledge Scale. The response patterns and psychometric properties of both questionnaires were assessed in order to test the construct validity of the simplified version. RESULTS: The mean age of the respondents was 57 years (range 21-83 years) and 64% were men. Respondents attained an average score of 65% on the Simplified Diabetes Knowledge Scale, compared with 62% on the Revised Diabetes Knowledge Scale. Overall, the Simplified Diabetes Knowledge Scale appeared to be somewhat easier to complete compared with the Revised Diabetes Knowledge Scale, as indicated by the number of missing responses. CONCLUSIONS: The Simplified Diabetes Knowledge Scale provides researchers with a brief and simple diabetes knowledge questionnaire with favourable psychometric properties. The scale may require further updating to include other items relevant to diabetes education. This simplified version will now undergo translation and validation for use among minority ethnic groups resident in the UK.

An FTO variant is associated with Type 2 diabetes in South Asian populations after accounting for body mass index and waist circumference.

AIMS: A common variant, rs9939609, in the FTO (fat mass and obesity) gene is associated with adiposity in Europeans, explaining its relationship with diabetes. However, data are inconsistent in South Asians. Our aim was to investigate the association of the FTO rs9939609 variant with obesity, obesity-related traits and Type 2 diabetes in South Asian individuals, and to use meta-analyses to attempt to clarify to what extent BMI influences the association of FTO variants with diabetes in South Asians. METHODS: We analysed rs9939609 in two studies of Pakistani individuals: 1666 adults aged ≥40 years from the Karachi population-based Control of Blood Pressure and Risk Attenuation (COBRA) study and 2745 individuals of Punjabi ancestry who were part of a Type 2 diabetes case-control study (UK Asian Diabetes Study/Diabetes Genetics in Pakistan; UKADS/DGP). The main outcomes were BMI, waist circumference and diabetes. Regression analyses were performed to determine associations between FTO alleles and outcomes. Summary estimates were combined in a meta-analysis of 8091 South Asian individuals (3919 patients with Type 2 diabetes and 4172 control subjects), including those from two previous studies. RESULTS: In the 4411 Pakistani individuals from this study, the age-, sex- and diabetes-adjusted association of FTO variant rs9939609 with BMI was 0.45 (95%CI 0.24-0.67) kg/m(2) per A-allele (P=3.0 × 10(-5) ) and with waist circumference was 0.88 (95% CI 0.36-1.41) cm per A-allele (P=0.001). The A-allele (30% frequency) was also significantly associated with Type 2 diabetes [per A-allele odds ratio (95%CI) 1.18 (1.07-1.30); P=0.0009]. A meta-analysis of four South Asian studies with 8091 subjects showed that the FTO A-allele predisposes to Type 2 diabetes [1.22 (95%CI 1.14-1.31); P=1.07 × 10(-8) ] even after adjusting for BMI [1.18 (95%CI 1.10-1.27); P=1.02 × 10(-5) ] or waist circumference [1.18 (95%CI 1.10-1.27); P=3.97 × 10(-5) ]. CONCLUSIONS: The strong association between FTO genotype and BMI and waist circumference in South Asians is similar to that observed in Europeans. In contrast, the strong association of FTO genotype with diabetes is only partly accounted for by BMI.