All-cause mortality risk among a national sample of individuals with diabetes

Semaglutide and smoking cessation in individuals with type 2 diabetes mellitus: there is no smoke without fire!

Tobacco use represents the leading preventable risk factor for premature deaths worldwide. A meta-analysis of 74 epidemiological studies, including 3.2 million individuals with type 2 diabetes mellitus (T2DM) from 33 countries, reported a pooled prevalence of smoking of 20.8% among individuals with T2DM. Cigarette smoking further aggravates existing deleterious vascular effects of T2DM. Namely, chronic hyperglycemia and exposure to cigarette smoke cause additive injurious effect on the endothelium, leading to an acceleration of vascular complications seen in persons with T2DM and tobacco use disorders (TUD). In a recent study, Wang and colleagues found that semaglutide use was associated with a significantly lower risk for medical encounters for TUD, when compared to other antidiabetic drug classes; indeed, this effect was strongest compared with insulins and weakest compared with other glucagon-like peptide-1 receptor agonists. Semaglutide was associated with reduced smoking cessation medication prescriptions and counseling. Similar findings were observed irrespective of the presence of obesity. Therefore, semaglutide use might be useful in terms of smoking cessation among individuals with T2DM, thus offering an additional benefit for this constantly growing population. However, those interesting findings should be confirmed through dedicated, large-scale randomized controlled trials.

The protective effects of curcumin against cigarette smoke-induced toxicity: A comprehensive review

Cigarette smoking (CS) is a crucial modifiable risk of developing several human diseases and cancers. It causes lung, bladder, breast, and esophageal cancers, respiratory disorders, as well as cardiovascular and metabolic diseases. Because of these adverse health effects, continual efforts to decrease the prevalence and toxicity of CS are imperative. Until the past decades, the impacts of natural compounds have been under investigation on the harmful effects of CS. Turmeric (Curcuma longa), a rhizomatous herbaceous perennial plant that belongs to the Zingiberaceae family, is the main source of curcumin. This review is an attempt to find out the current knowledge on CS's harmful effects and protective potential of curcumin in the pulmonary, liver, brain, gastrointestinal, and testis organs. According to the present review, simultaneous consumption of curcumin and CS can attenuate CS toxicities including chronic obstructive pulmonary disease, gastrointestinal toxicity, metabolic diseases, testis injury, and neurotoxicity. Moreover, curcumin suppresses carcinogenesis in the skin, liver, lungs, breast, colon, and stomach. Curcumin mediates these protective effects through antioxidant, anti-inflammatory, anti-apoptotic, and anti-carcinogenicity properties.

The relationship between mortality and daily number of steps in type 2 diabetes

BACKGROUND

Physical activity (PA) is an established modifiable factor for the prevention of cardiovascular disease. Our objective was to assess the association of PA with mortality rates in a national sample of patients with diabetes.

METHODS

We analyzed a nationally representative sample from The National Health and Nutrition Examination Survey (NHANES, periods 2003-2004 and 2005-2006) that used PA Monitors. Individuals were matched for BMI, number of steps/per day and age. Three groups were created: subjects with less than 5000/steps per day (low), 5000-7500/steps per day (moderate) and more than 7500/steps per day (high levels of physical activity). All-cause mortality was ascertained through December 2015.

RESULTS

A sample of 3072 individuals (1018 with diabetes) was analyzed. Patients with diabetes had 30% increased risk of mortality of all causes (RR: 1.298, 95% CI [1.162-1.451], P<0.001), higher levels of PA (>7500 steps/day) provided similar relative risk for subjects with diabetes compared to their controls (RR:1.256 [95% CI 0.910-1.732]). In a Poisson model adjusted for sex, history of previous cardiovascular event or cancer, ethnicity, Hb1ac, SBP, and total cholesterol to HDL ratio, patients with diabetes and moderate or high PA had an associated 44% to 80% lower risk of all-cause mortality compared to those with low PA.

CONCLUSIONS

The subgroup of patients with diabetes and high PA had no excess of mortality compared to the general population. PA can reduce the gap for all-cause mortality, used as an index of cardiovascular fitness and a clinical tool for the assessment of mortality risk.

Diabetes with poor-control HbA1c is cardiovascular disease 'risk equivalent' for mortality: UK Biobank and Hong Kong population-based cohort study

INTRODUCTION

Type 2 diabetes mellitus (T2DM) has traditionally been considered a coronary heart disease 'risk equivalent' for future mortality, but significant heterogeneity exists across people with T2DM. This study aims to determine the risk of all-cause mortality of patients with cardiovascular disease (CVD) and T2DM in UK and Hong Kong, with stratifications for hemoglobin A1 (HbA1c) concentrations, compared with those without CVD and diabetes mellitus.

RESEARCH DESIGN AND METHODS

This is a retrospective cohort study of 3 839 391 adults from Hong Kong and a prospective cohort study of 497 779 adults from the UK Biobank. Individuals were divided into seven disease groups: (1) no T2DM and CVD, (2) T2DM only with HbA1c <7%, (3) T2DM only with HbA1c 7%-7.9%, (4) T2DM only with HbA1c 8%-8.9%, (5) T2DM only with HbA1c ≥9%, (6) CVD only, and (7) T2DM and CVD. Differences in all-cause mortality between groups were examined using Cox regression.

RESULTS

After around 10 years of median follow-up, 423 818 and 19 844 deaths were identified in the Hong Kong cohort and UK Biobank, respectively. Compared with individuals without T2DM and CVD, the adjusted HR for all-cause mortality in the other six disease groups for the Hong Kong cohort was 1.25 (95% CI 1.23 to 1.27) for T2DM only with HbA1c <7%, 1.21 (95% CI 1.19 to 1.23) for T2DM only with HbA1c 7%-7.9%, 1.36 (95% CI 1.33 to 1.39) for T2DM only with HbA1c 8%-8.9%, 1.82 (95% CI 1.78 to 1.85) for T2DM only with HbA1c ≥9%, 1.37 (95% CI 1.36 to 1.38) for CVD only, and 1.83 (95% CI 1.81 to 1.85) for T2DM and CVD, and for the UK Biobank the HR was 1.45 (95% CI 1.33 to 1.58), 1.50 (95% CI 1.32 to 1.70), 1.72 (95% CI 1.43 to 2.08), 2.51 (95% CI 2.05 to 3.08), 1.67 (95% CI 1.59 to 1.75) and 2.62 (95% CI 2.42 to 2.83), respectively. This indicates that patients with T2DM had an increased risk of mortality compared with those without T2DM and CVD, and in those with HbA1c ≥9% an even higher risk than people with CVD.

CONCLUSIONS

Patients with T2DM with poor HbA1c control (8%-8.9% and ≥9%) were associated with similar and higher risk of mortality compared with patients with CVD, respectively. Optimal HbA1c, controlled for risk reduction and prevention of mortality and complications in diabetes management, remains important.

The relationship between C-Reactive protein and mortality in adults with diabetes: Influences of demographic characteristics, lifestyle behaviors, and medications

BACKGROUND AND AIMS

This study assesses the influence of demographic, lifestyle, and medication in the association between CRP and mortality in a national sample of adults with diabetes.

METHODS AND RESULTS

Cross-sectional study of data from 1999 to 2010 National Health and Nutrition Examination Survey (unweighted n = 3952; Weighted n = 19,064,710). Individuals were categorized as having diabetes if told by a provider they had diabetes, were taking insulin or other diabetes medications, or had a glycosylated hemoglobin A1c (HbA1c) ≥ 6.5%. CRP was classified into four categories: normal (≤0.1 mg/dL); moderate risk (0.11-0.3 mg/dL); high-risk (0.31-1.0 mg/dL); very high-risk (>1.0 mg/dL). Higher risk for mortality was associated with a very high-risk of CRP (HR = 1.88 (95% CI: 1.27-2.78), being a current (HR = 1.49 (95% CI: 1.10-2.01) or former (HR = 1.34 (95% CI: 1.03-1.73) smoker, and taking insulin (HR = 1.60 (95% CI: 1.25-2.05), taking anti-hypertensives (HR = 1.50 (95% CI: 1.22-1.85), and having co-morbidities such as cancer (HR = 1.32 (95% CI: 1.05-1.66) and hepatitis infection (HR = 1.76 (95% CI: 1.07-2.91), while taking Metformin (HR = 0.62 (95% CI: 0.50-0.76) had a lower risk of mortality.

CONCLUSION

In this sample of adults with diabetes, demographic, lifestyle, and medication factors influenced the association between CRP and mortality. Interventions should focus on these factors to reduce mortality in adults with diabetes.

A double blind randomized controlled trial investigating efficacy and safety of varenicline for smoking cessation in patients with type 2 diabetes: study protocol

Reducing exposure to cigarette smoke is an imperative for public health and for diabetic patients. Patients with diabetes who continue to smoke face challenges at quitting and the delivery of effective smoking cessation interventions is a major unmet need. The high-affinity α4β2 nicotinic acetylcholine receptor partial agonist varenicline in combination with counseling is effective for smoking cessation, but evidence in patients with diabetes is limited. A clinical trial of varenicline targeted specifically at smokers with T2DM is warranted. This randomized, double blind, placebo-controlled trial will be the first study to test efficacy and safety of varenicline in smokers with type 2 diabetes mellitus (T2DM) over the course of 52 weeks. We hypothesize that varenicline treatment (1 mg BID, administered for 12 weeks) would increase quit rates, maintain smoking abstinence up to 1 year after treatment, and be well-tolerated in T2DM smokers intending to quit. Efficacy end points will include carbon monoxide-confirmed continuous abstinence rate (CAR) and 7-day point prevalence of abstinence. The results of this RCT will help inform medical/health authorities and physicians worldwide whether an optimally varenicline-treated cohort of T2DM patients who smoke will experience significant success rates, without significant side effects.Trial registration NCT01387425 ( https://clinicaltrials.gov/ct2/show/NCT01387425 ).

Association of Cycling With All-Cause and Cardiovascular Disease Mortality Among Persons With Diabetes: The European Prospective Investigation Into Cancer and Nutrition (EPIC) Study

Importance

Premature death from all causes and cardiovascular disease (CVD) causes is higher among persons with diabetes.

Objective

To investigate the association between time spent cycling and all-cause and CVD mortality among persons with diabetes, as well as to evaluate the association between change in time spent cycling and risk of all-cause and CVD mortality.

Design, Setting, and Participants

This prospective cohort study included 7459 adults with diabetes from the European Prospective Investigation into Cancer and Nutrition study. Questionnaires regarding medical history, sociodemographic, and lifestyle information were administered in 10 Western European countries from 1992 through 2000 (baseline examination) and at a second examination 5 years after baseline. A total of 5423 participants with diabetes completed both examinations. The final updated primary analysis was conducted on November 13, 2020.

Exposures

The primary exposure was self-reported time spent cycling per week at the baseline examination. The secondary exposure was change in cycling status from baseline to the second examination.

Main Outcomes and Measures

The primary and secondary outcomes were all-cause and CVD mortality, respectively, adjusted for other physical activity modalities, diabetes duration, and sociodemographic and lifestyle factors.

Results

Of the 7459 adults with diabetes included in the analysis, the mean (SD) age was 55.9 (7.7) years, and 3924 (52.6%) were female. During 110 944 person-years of follow-up, 1673 deaths from all causes were registered. Compared with the reference group of people who reported no cycling at baseline (0 min/wk), the multivariable-adjusted hazard ratios for all-cause mortality were 0.78 (95% CI, 0.61-0.99), 0.76 (95% CI, 0.65-0.88), 0.68 (95% CI, 0.57-0.82), and 0.76 (95% CI, 0.63-0.91) for cycling 1 to 59, 60 to 149, 150 to 299, and 300 or more min/wk, respectively. In an analysis of change in time spent cycling with 57 802 person-years of follow-up, a total of 975 deaths from all causes were recorded. Compared with people who reported no cycling at both examinations, the multivariable-adjusted hazard ratios for all-cause mortality were 0.90 (95% CI, 0.71-1.14) in those who cycled and then stopped, 0.65 (95% CI, 0.46-0.92) in initial noncyclists who started cycling, and 0.65 (95% CI, 0.53-0.80) for people who reported cycling at both examinations. Similar results were observed for CVD mortality.

Conclusion and Relevance

In this cohort study, cycling was associated with lower all-cause and CVD mortality risk among people with diabetes independent of practicing other types of physical activity. Participants who took up cycling between the baseline and second examination had a considerably lower risk of both all-cause and CVD mortality compared with consistent noncyclists.

Cigarette smoking and nicotine exposure contributes for aberrant insulin signaling and cardiometabolic disorders

Cigarette smoking- and nicotine-mediated dysregulation in insulin-signaling pathways are becoming leading health issues associated with morbidity and mortality worldwide. Many cardiometabolic disorders particularly insulin resistance, polycystic ovary syndrome (PCOS), central obesity and cardiovascular diseases are initiated from exposure of exogenous substances which augment by disturbances in insulin signaling cascade. Among these exogenous substances, nicotine and cigarette smoking are potential triggers for impairment of insulin-signaling pathways. Further, this aberrant insulin signaling is associated with many metabolic complications, which consequently give rise to initiation as well as progression of these metabolic syndromes. Hence, understanding the underlying molecular mechanisms responsible for cigarette smoking- and nicotine-induced altered insulin signaling pathways and subsequent participation in several health hazards are quite essential for prophylaxis and combating these complications. In this article, we have focused on the role of nicotine and cigarette smoking mediated pathological signaling; for instance, nicotine-mediated inhibition of nuclear factor erythroid 2-related factor 2 and oxidative damage, elevated cortisol that may promote central obesity, association PCOS and oxidative stress via diminished nitric oxide which may lead to endothelial dysfunction and vascular inflammation. Pathological underlying molecular mechanisms involved in mediating these metabolic syndromes via alteration of insulin signaling cascade and possible molecular mechanism responsible for these consequences on nicotine exposure have also been discussed.

Association of mitochondrial DNA copy number with prevalent and incident type 2 diabetes in women: A population-based follow-up study

Mitochondrial dysfunction is an important factor of the aging process and may play a key role in various diseases. Mitochondrial DNA copy number (mtDNA-CN) is an indirect measure of mitochondrial dysfunction and is associated with type 2 diabetes mellitus (T2DM); however, whether mtDNA-CN can predict the risk of developing T2DM is not well-known. We quantified absolute mtDNA-CN in both prevalent and incident T2DM by well-optimized droplet digital PCR (ddPCR) method in a population-based follow-up study of middle aged (50-59 years) Swedish women (n = 2387). The median follow-up period was 17 years. Compared to those who were free of T2DM, mtDNA-CN was significantly lower in both prevalent T2DM and in women who developed T2DM during the follow-up period. Mitochondrial DNA-copy number was also associated with glucose intolerance, systolic blood pressure, smoking status and education. In multivariable Cox regression analysis, lower baseline mtDNA-CN was prospectively associated with a higher risk of T2DM, independent of age, BMI, education, smoking status and physical activity. Moreover, interaction term analysis showed that smoking increased the effect of low mtDNA-CN at baseline on the risk of incident T2DM. Mitochondrial DNA-copy number may be a risk factor of T2DM in women. The clinical usefulness of mtDNA-CN to predict the future risk of T2DM warrants further investigation.

Trimetazidine combined with exercise improves exercise capacity and anti-fatal stress ability through enhancing mitochondrial quality control

AIMS

To explore the effects of trimetazidine combined with exercise on EC and anti-fatal stress ability, and illustrate the underlying mechanism.

METHODS

C57BL/6 mice were randomly assigned to four groups (n = 11 in each group): the control, exercise, trimetazidine and trimetazidine + exercise (TE) groups. Mice were accordingly given saline (ig), Aerobic exercise (AE), trimetazidine (ig), or a combination of trimetazidine (ig) and AE for five weeks. After the intervention, each group was randomly subdivided into rest and exhaustive exercise (EE) subgroups. The mice in the control-EE and TE-EE subgroups underwent fatal stress experiments. EC and anti-fatal stress ability were assessed respectively. Mitochondrial quality control (MQC) in skeletal muscle were measured at the protein level and the organelle level.

KEY FINDINGS

A significantly increased exhaustive swimming time was observed in exercise (39.10 ± 12.58 min vs 14.18 ± 4.37 min), trimetazidine (33.73 ± 8.45 min vs 14.18 ± 4.37 min) and TE groups (73.78 ± 18.95 min vs 14.18 ± 4.37 min) compared with that in the control group, and a synergistic effect was detected (P < 0.05). Fatal stress experiments successfully induced skeletal muscle damage, including increased creatine kinase activity, myofibrosis, and impaired antioxidative enzyme system, all those were significantly alleviated by trimetazidine supplementation combined with AE precondition (P < 0.05). Meanwhile, AE and trimetazidine alone or combined, significantly enhanced the MQC in normal mice by activating mitochondrial biogenesis, dynamics and mitophagy, and that in mice underwent fatal stress stimulus (P < 0.05).

SIGNIFICANCE

This study for the first time found that trimetazidine and AE have synergistic effects on improving EC. Moreover, the combination of both interventions enhances anti-fatal stress ability. Enhancing MQC may be a key mechanism of AE combined with trimetazidine that improves EC and anti-fatal stress ability.

Relationship between HbA1c and all-cause mortality in older patients with insulin-treated type 2 diabetes: results of a large UK Cohort Study

BACKGROUND

our aim was to study the relationship between HbA1c and cardiovascular morbidity and all-cause mortality among older insulin-treated patients with type 2 diabetes (T2D) after adjustment for multiple confounders.

METHODS

data for 4589 adults with T2D (>65 years) on insulin treatment were sourced from 532 UK General Practices via the Health Improvement Network (THIN) database. Cox proportional hazard models and Kaplan-Meier estimators were fitted to derive the hazards of all-cause mortality by HbA1c categories (<6.5, 6.5-7.4, 7.5-8.4, 8.5-9.4, 9.5-10.4, 10.5-11.4%; and 11.5% and above) after 5 years of follow-up following insulin initiation.

RESULTS

we observed a U-shaped relationship between all-cause mortality and HbA1c, with the lowest risk seen in the HbA1c range of 6.5-7.4% and marked increased in risk with HbA1c > 11%. The highest mortality risks of 31 and 40% were significantly associated with the lowest (<6.5%) and highest (11.5% and above) HbA1c categories: aHR: 1.31; (95%CI: 1.10-1.56; P = 0.002) and aHR: 1.40; (95%CI: 1.01-1.96; P = 0.039), respectively.

CONCLUSIONS

both low and high HbA1c were associated with increased all-cause mortality, among older patients with insulin-treated T2D. This cohort study supports the need for individualisation of care and suggests better outcomes with HbA1c levels around 6.5-7.4% and markedly excess risk with HbA1c > 11.

Smoking and diabetes: dangerous liaisons and confusing relationships

The combined harmful effects of cigarette smoking and hyperglycemia can accelerate vascular damage in patients with diabetes who smoke, as is well known. Can smoking cause diabetes? What are the effects of smoking on macro and microvascular complications? Now growing evidence indicates that regular smokers are at risk of developing incident diabetes. Since the prevalence rates of smoking in patients with diabetes are relatively similar to those of the general population, it is essential to address the main modifiable risk factor of smoking to prevent the onset of diabetes and delay the development of its complications. Quitting smoking shows clear benefits in terms of reducing or slowing the risk of cardiovascular morbidity and mortality in people with diabetes. Does quitting smoking decrease the incidence of diabetes and its progression? What are the effects of quitting smoking on complications? The current evidence does not seem to unequivocally suggest a positive role for quitting in patients with diabetes. Quitting smoking has also been shown to have a negative impact on body weight, glycemic control and subsequent increased risk of new-onset diabetes. Moreover, its role on microvascular complications of the disease is unclear. What are the current smoking cessation treatments, and which ones are better for patients with diabetes? Stopping smoking may be of value for diabetes prevention and management of the disease and its macrovascular and microvascular complications. Unfortunately, achieving long-lasting abstinence is not easy and novel approaches for managing these patients are needed. This narrative review examines the evidence on the impact of smoking and smoking cessation in patients with diabetes and particularly in type 2 diabetes mellitus and its complications. In addition, management options and potential future directions will be discussed.

Physical activity and type 2 diabetes mellitus risk: population studies review

Physical activity is one of the most important components of a healthy lifestyle. Regular physical activity helps to maintain normal blood glucose levels and reduce the risk of type 2 diabetes mellitus. This review presents population studies investigating physical activity as a factor for type 2 diabetes mellitus risk. A search using the keywords ‘physical activity’, ‘type 2 diabetes mellitus’ and ‘risk’ identified more than 40 relevant original studies and meta-analyses, which are presented in this review. Different types of physical activity have positive protective effects on type 2 diabetes mellitus risk and reduce the risk of death in patients with type 2 diabetes mellitus.

Varenicline in smokers with diabetes: A pooled analysis of 15 randomized, placebo-controlled studies of varenicline

Aims/Introduction

Stopping smoking deserves high priority in preventing complications of diabetes; however, only sparse data are available regarding the efficacy of pharmacotherapy in smokers with diabetes. We assessed the efficacy and safety of varenicline in smokers with diabetes who participated in 15 double‐blind, randomized, placebo‐controlled studies.

Materials and Methods

This retrospective pooled analysis included data from smokers of ≥10 cigarettes per day with diabetes. Participants received varenicline 1 mg b.i.d. or placebo for 12 weeks. We examined carbon monoxide‐confirmed continuous abstinence rates (CARs) for weeks 9–12, 9–24 and 9–52, and compared safety in participants with and without diabetes.

Results

Of 6,771 participants, 323 had diabetes (varenicline n = 162; placebo n = 161). Week 9–12 CAR was higher with varenicline than placebo (43.8% vs 24.8%; odds ratio 2.36, 95% CI 1.47–3.79), as was week 9–24 CAR (27.5% vs 14.4%; odds ratio 2.25, 95% CI 1.27–4.00). Week 9–52 CAR was 18.4% for varenicline and 10.1% for placebo (odds ratio 2.00, 95% CI 0.90–4.49). The most commonly‐reported adverse events in participants with diabetes for varenicline vs placebo were: nausea (27.2% vs 8.1%); headache (9.3% vs 9.9%); and insomnia (8.6% vs 5.6%), incidences that were similar in participants without diabetes (29.6% vs 9.7%; 13.4% vs 10.9%; and 11.4% vs 7.1%, respectively). Weight gain in quitters with diabetes (1.7 kg) was similar to that of those without diabetes (2.1 kg).

Conclusions

Varenicline was an effective and well‐tolerated aid for smoking cessation in individuals with diabetes. Safety was comparable with participants without diabetes.

Misconceptions about smoking in patients with type 2 diabetes mellitus: a qualitative analysis

AIMS AND OBJECTIVES

To investigate the smoking behaviours, perceptions about quitting smoking and factors associated with intention to quit in patients with type 2 diabetes mellitus.

BACKGROUND

Smoking causes type 2 diabetes mellitus. There has been limited research on the needs and concerns of smokers with type 2 diabetes mellitus about quitting smoking.

DESIGN

The study used a qualitative design.

METHODS

Patients diagnosed with type 2 diabetes mellitus who had a history of smoking were recruited at the outpatient diabetic clinics of two major local hospitals in Hong Kong for a semi-structured interview (n = 42), guided by the theory of planned behaviour.

RESULTS

At data saturation, 22 current smokers and 20 ex-smokers with type 2 diabetes mellitus were recruited. The current smokers reported they had not quit smoking because of satisfaction with present health status, and misconceptions about the association between diabetes and smoking, and the perceived hazards of quitting. In contrast, ex-smokers had a positive opinion about quitting smoking, accepted advice about quitting from health professionals and received more family support than current smokers. Psychological addiction and weight gain after cessation made quitting challenging.

CONCLUSIONS

Satisfaction with health status, inadequate knowledge about the relationship between type 2 diabetes mellitus and smoking, and misconceptions about quitting smoking resulted in negative attitudes toward quitting by type 2 diabetes mellitus smokers. Smoking peers, psychological addiction and post-cessation weight gain hindered the quitting process.

RELEVANCE TO CLINICAL PRACTICE

Education on the causal link between smoking, type 2 diabetes mellitus and its complications is important to raise health awareness and counter misconceptions about quitting smoking. Behavioural counselling with weight control strategies should be part of a comprehensive smoking cessation intervention for type 2 diabetes mellitus smokers.

Increased plasma DPP4 activities predict new-onset hyperglycemia in Chinese over a four-year period: possible associations with inflammation

OBJECTIVE

DPP4, a novel proinflammatory cytokine, is involved in the inflammatory process through its interaction with the IGF-II/M6P receptor. Our objective was to determine whether DPP4 acts as a link between low-grade chronic inflammation and hyperglycemia.

DESIGN AND METHODS

A prospective cohort study was conducted with 486 adults (177 men and 309 women) aged 18 to 70years without hyperglycemia examined in 2007 (baseline) and 2011 (follow-up). Circulating DPP4 activity, IGF-II/M6P receptor, and inflammatory markers were measured at baseline and four years later.

RESULTS

After a four-year follow-up period, 111 individuals developed hyperglycemia (71 prediabetes and 40 type 2 diabetes). According to the multiple linear regression analysis, the baseline DPP4 activity was an independent predictor of an increase in the IGF-II/M6P receptor, inflammatory markers, and insulin resistance over the four-year period (all P <0.05). In the multivariable-adjusted models, the odds ratio (OR) for incident hyperglycemia comparing the highest and lowest quartiles of DPP4 activity was 2.90 (95% CI 1.47-5.73) after adjustment for confounding risk factors (P=0.002). The incidence of hyperglycemia because of DPP4 activity increased by 9.47%. Furthermore, the plasma DPP4 activity significantly improved the area under the ROC curve for predicting new-onset hyperglycemia based on the information from the baseline levels of the risk factors (P=0.036).

CONCLUSIONS

DPP4 activity is an important predictor of the onset of insulin resistance and hyperglycemia in apparently healthy Chinese. This finding may have important implications for understanding the proinflammatory role of DPP-4 in the development and pathogenesis of hyperglycemia.

Education, glucose control, and mortality risks among U.S. older adults with diabetes

AIMS

Studies have shown that diabetes mellitus disproportionately afflicts persons of low socioeconomic status and that the burden of disease is greatest among the disadvantaged. However, our understanding of educational differences in the control of diabetes and its impact on survival is limited. This study investigated the associations among education, hemoglobin A1c (HbA1c), and subsequent mortality in adults with diabetes.

METHODS

Prospective cohort data from the 2006, 2008, and 2010 Health and Retirement Study were linked with biomarker data for U.S. older adults with diabetes (n=3312). Weighted distributions were estimated for all subjects at baseline and by the American Diabetes Association's general guidelines for HbA1c control (<7.0% [53 mmol/mol] vs. ≥7.0% [53 mmol/mol]). Proportional hazard models were used to estimate educational differences in all-cause mortality by HbA1c level with sequential adjustments for contributing risk factors.

RESULTS

Mortality risks associated with HbA1c≥7.0% [53 mmol/mol] were significantly greater in lower-educated adults than higher-educated adults (P<0.001). We found that the hazard ratios (HR) associated with HbA1c ≥7.0% [53 mmol/mol] were highest among low-educated adults (HR=2.18, 95% CI: 1.62, 2.94) and that a combination of socioeconomic, psychosocial, and behavioral factors accounted for most, but not all, of the associations.

CONCLUSIONS

Educational differences in HbA1c control have significant implications for mortality and efforts to reduce these disparities should involve more vigilant screening and monitoring of lower-educated adults with diabetes.

Increased plasma DPP4 activity predicts new-onset hypertension in Chinese over a 4-year period: possible associations with inflammation and oxidative stress

To investigate whether increased dipeptidyl peptidase 4 (DPP4) activity predicts new-onset hypertension in Chinese patients. A prospective study was conducted for 1884 adults (804 men/1080 women) aged 18-70 years without hypertension. Participants were examined in 2007 (baseline) and 2011 (follow-up) and circulating DPP4 activity, mannose 6-phosphate receptor (M6P-R) concentration, inflammatory markers and oxidative stress parameters were measured. After a 4-year follow-up, 296 individuals developed hypertension with an incidence of 39 per 1000 patient years. In multiple linear regression analyses, baseline DPP4 activity was an independent predictor of an increase in M6P-R, inflammatory markers and oxidative stress parameters over a 4-year period (all P < 0.01). Cox proportional hazards models revealed that DPP4 activity independently predicted the risk of developing hypertension (relative risk 2.68 (95% confidence interval 1.71-4.21) P < 0.01). Our results indicate that DPP4 activity is an important predictor of hypertension onset in apparently healthy Chinese individuals. This finding may have important implications for understanding the effects of DPP4 in promoting inflammation and oxidative stress in the pathogenesis of hypertension.

Increased plasma DPP4 activities predict new-onset atherosclerosis in association with its proinflammatory effects in Chinese over a four year period: A prospective study

OBJECTIVE

DPP4, a novel proinflammatory cytokine, is involved in the inflammatory process through its interaction with IGF-II/M6P receptor. We aimed to investigate whether it could predict new-onset atherosclerosis in Chinese.

METHODS

A prospective study was conducted of 590 adults (213 men and 377 women) aged 18-70 years without atherosclerosis examined in 2007(baseline) and 2011(follow-up). Circulating DPP4 activity, inflammatory markers, IGF-II/M6P receptor and common carotid artery Intima-Media Thickness (C-IMT) were measured at baseline and four years later.

RESULTS

At baseline, individuals in the highest quartile of DPP4 activity had higher age, WHR, BMI, SBP, fasting insulin, 2h-PG, TG, LDL-C, IL-6, hs-CRP, IGF-II/M6P-R, C-IMT and lower HDL-C compared with individuals in the lowest quartile. After a 4-year follow-up, 71 individuals developed atherosclerosis. In multiple linear regression analysis, baseline DPP4 activity was an independent predictor of an increase in inflammatory markers, IGF-II/M6P receptor, and C-IMT over a 4-year period (all P < 0.01). In multivariable-adjusted models, the odds ratio (OR) for incident atherosclerosis comparing the highest with the lowest quartiles of DPP4 activity was 3.17 (95%CI 1.33-7.58) after adjustment for confounding risk factors (P = 0.009). The incidence of atherosclerosis owing to DPP4 activity increased by 12.41%.

CONCLUSIONS

DPP4 activity is an important predictor of the onset of inflammation and atherosclerosis in apparently healthy Chinese. This finding may have important implications for understanding the proinflammatory role of DPP-4 in the pathogenesis of atherosclerosis.

Physical activity and risk of all-cause and cardiovascular disease mortality in diabetic adults from Great Britain: pooled analysis of 10 population-based cohorts

OBJECTIVE To examine associations between specific types of physical activity and all-cause and cardiovascular disease (CVD) mortality in a large nationally representative sample of adults with diabetes from Great Britain. RESEARCH DESIGN AND METHODS There were a total of 3,038 participants (675 deaths) with diabetes in the Health Survey for England and the Scottish Health Surveys conducted between 1997 and 2008. Participants aged ≥50 years at baseline were followed up for an average of 75.2 months for all-cause and CVD mortality. Data were collected on self-reported frequency, duration, and intensity of participation in sports and exercise, walking, and domestic physical activity, from which the number of MET-hours/week were derived. Sex-specific medians of time spent in each type of physical activity (for those physically active) were calculated, and Cox proportional hazards regression conducted to examine type-specific associations between the level of physical activity and all-cause and CVD mortality risk. RESULTS Inverse associations with all-cause and CVD mortality were observed for overall physical activity in a dose-response manner after adjusting for covariates. Compared with those who individuals were inactive, participants who reported some activity, but below the recommended amount, or who met the physical activity recommendations had a 26% (95% CI 39-11) and 35% (95% CI 47-21) lower all-cause mortality, respectively. Similar results were found for below/above median physical activity levels. Sports and exercise participation was inversely associated with all-cause (but not CVD) mortality, as were above average levels of walking. Domestic physical activity was not associated with mortality. CONCLUSIONS Moderate physical activity levels were associated with better prognosis in diabetic adults.

Smoking behavior among US adults with diabetes or impaired fasting glucose

BACKGROUND

Cigarette smoking is a well-known cardiovascular risk factor and its impact on cardiovascular disease is even greater among people with diabetes. The aim of this study is to compare the prevalence and determinants of smoking among US adults with diabetes or impaired fasting glucose, and those without diabetes or impaired fasting glucose.

METHODS

We analyzed data from the National Health and Nutrition Examination Surveys (1999-2008). Age-adjusted prevalence of smoking was calculated, and we used logistic regression models to identify the correlates of smoking among people with diabetes, impaired fasting glucose, and normal glucose metabolism.

RESULTS

Among 24,649 participants ≥20 years old, age-adjusted smoking prevalence was 25.7% in 3111 individuals with diabetes, 24.2% in 3557 individuals with impaired fasting glucose, and 24.1% in 17,981 individuals without diabetes. Smoking prevalence did not differ across groups or change over time (1999-2008) in any group. Younger age, less education, more alcohol consumption, less physical activity, and major depression symptoms were associated with smoking in people with diabetes, impaired fasting glucose, and normal glucose metabolism.

CONCLUSIONS

In the US, smoking prevalence among people with diabetes and impaired fasting glucose has not changed and is comparable with the nondiabetic population. Tobacco control efforts should be intensified among this population at high risk for complications and mortality.

Leisure-time physical activity is a significant predictor of stroke and total mortality in Japanese patients with type 2 diabetes: analysis from the Japan Diabetes Complications Study (JDCS)

AIMS/HYPOTHESIS

Our aim was to clarify the association between leisure-time physical activity (LTPA) and cardiovascular events and total mortality in a nationwide cohort of Japanese diabetic patients.

METHODS

Eligible patients (1,702) with type 2 diabetes (mean age, 58.5 years; 47% women) from 59 institutes were followed for a median of 8.05 years. A comprehensive lifestyle survey including LTPA and occupation was performed using standardised questionnaires. Outcome was occurrence of coronary heart disease (CHD), stroke and total mortality. The adjusted HR and 95% CI were calculated by Cox regression analysis.

RESULTS

A significant reduction in HR in patients in the top (≥ 15.4 metabolic equivalents [MET] h/week) vs the bottom tertile (≤ 3.7 MET h/week) of LTPA, adjusted by age, sex and diabetes duration, was observed in stroke (HR 0.55, 95% CI 0.32, 0.94) and total mortality (HR 0.49, 95% CI 0.26, 0.91) but not in CHD (HR 0.77, 95% CI 0.48, 1.25). The HR for stroke became borderline significant or nonsignificant after adjustment for lifestyle or clinical variables including diet or serum lipids. The significantly reduced total mortality by LTPA was independent of these variables and seemed not to be, at least mainly, attributed to reduced cardiovascular disease.

CONCLUSIONS/INTERPRETATION

In Japanese persons with type 2 diabetes, LTPA of 15.4 MET h/week or more was associated with a significantly lower risk of stroke partly through ameliorating combinations of cardiovascular risk factors. It was also associated with significantly reduced total mortality but independently of cardiovascular risk factors or events. These findings, implying differences from Western diabetic populations, should be considered in the clinical management of East Asians with diabetes.

[Glycaemic control and complications of diabetes: what about?]

In France, 2.8 millions of patients have type 2 diabetes, which is a well-established risk factor for cardiovascular disease. In about 15 years, several large clinical trials tried to study the relationship between a tight glycaemic control and the occurrence of micro- and macroangiopathy. Meta-analyses of targeting intensive versus conventional glycaemic control focused on divergent results. In type 1 diabetes, a tight glycaemic control reduced the occurrence of microangiopathy whereas more time, at least 5 years is needed to reduce macroangiopathy. Conclusions drawn from studies are less clear for type 2 diabetes and depend on the caracteristics of the population studied, particularly for retinopathy. When microalbuminuria is the judgement criteria, its progression is lower in the intensive group than in the conventional one and it takes more than about 5 years to emerge; the impact on glomerular filtration rate is less clear. Worries about the excess of mortality observed in the ACCORD study in the intensive treatment group were not described in other studies. The decrease of mortality was not associated with an intensive glyceamic control. Intensified multifactorial intervention is finally needed to improve microangiopathy.

Type 2 diabetes mellitus and exercise impairment

Limitations in physical fitness, a consistent finding in individuals with both type I and type 2 diabetes mellitus, correlate strongly with cardiovascular and all-cause mortality. These limitations may significantly contribute to the persistent excess cardiovascular mortality affecting this group. Exercise impairments in VO2 peak and VO2 kinetics manifest early on in diabetes, even with good glycemic control and in the absence of clinically apparent complications. Subclinical cardiac dysfunction is often present but does not fully explain the observed defect in exercise capacity in persons with diabetes. In part, the cardiac limitations are secondary to decreased perfusion with exercise challenge. This is a reversible defect. Similarly, in the skeletal muscle, impairments in nutritive blood flow correlate with slowed (or inefficient) exercise kinetics and decreased exercise capacity. Several correlations highlight the likelihood of endothelial-specific impairments as mediators of exercise dysfunction in diabetes, including insulin resistance, endothelial dysfunction, decreased myocardial perfusion, slowed tissue hemoglobin oxygen saturation, and impairment in mitochondrial function. Both exercise training and therapies targeted at improving insulin sensitivity and endothelial function improve physical fitness in subjects with type 2 diabetes. Optimization of exercise functions in people with diabetes has implications for diabetes prevention and reductions in mortality risk. Understanding the molecular details of endothelial dysfunction in diabetes may provide specific therapeutic targets for the remediation of this defect. Rat models to test this hypothesis are under study.

Lifetime risks of cardiovascular disease

BACKGROUND

The lifetime risks of cardiovascular disease have not been reported across the age spectrum in black adults and white adults.

METHODS

We conducted a meta-analysis at the individual level using data from 18 cohort studies involving a total of 257,384 black men and women and white men and women whose risk factors for cardiovascular disease were measured at the ages of 45, 55, 65, and 75 years. Blood pressure, cholesterol level, smoking status, and diabetes status were used to stratify participants according to risk factors into five mutually exclusive categories. The remaining lifetime risks of cardiovascular events were estimated for participants in each category at each age, with death free of cardiovascular disease treated as a competing event.

RESULTS

We observed marked differences in the lifetime risks of cardiovascular disease across risk-factor strata. Among participants who were 55 years of age, those with an optimal risk-factor profile (total cholesterol level, <180 mg per deciliter [4.7 mmol per liter]; blood pressure, <120 mm Hg systolic and 80 mm Hg diastolic; nonsmoking status; and nondiabetic status) had substantially lower risks of death from cardiovascular disease through the age of 80 years than participants with two or more major risk factors (4.7% vs. 29.6% among men, 6.4% vs. 20.5% among women). Those with an optimal risk-factor profile also had lower lifetime risks of fatal coronary heart disease or nonfatal myocardial infarction (3.6% vs. 37.5% among men, <1% vs. 18.3% among women) and fatal or nonfatal stroke (2.3% vs. 8.3% among men, 5.3% vs. 10.7% among women). Similar trends within risk-factor strata were observed among blacks and whites and across diverse birth cohorts.

CONCLUSIONS

Differences in risk-factor burden translate into marked differences in the lifetime risk of cardiovascular disease, and these differences are consistent across race and birth cohorts. (Funded by the National Heart, Lung, and Blood Institute.).

Excess risk of mortality and cardiovascular events associated with smoking among patients with diabetes: meta-analysis of observational prospective studies

BACKGROUND

Numerous studies have demonstrated that both smoking and diabetes are risk factors for mortality and caused-specific cardiovascular events. However, few studies systematically investigated to what extent the excess risk could be attributed to smoking among diabetic patients.

METHODS

Literature references were searched up to April 2011 in MEDLINE and EMBASE, supplemented by manual searches. Inclusion criteria were prospective cohort studies, assessment of the association between smoking and total mortality, cardiovascular death, incidence of coronary heart disease (CHD), stroke and myocardial infarction (MI) in diabetic patients.

RESULTS

Of 3758 studies in the literature searched, 46 were eligible with approximately 130,000 diabetic patients. The relative risk (RR) comparing smokers with nonsmokers was 1.48[95% confidential interval (CI): 1.34-1.64] for total mortality (27 studies), 1.36(1.22-1.52) for cardiovascular mortality (9 studies), 1.54(1.31-1.82) for CHD (13 studies), 1.44(1.28-1.61) for stroke (9 studies) and 1.52(1.25-1.83) for MI (7 studies). Furthermore, the excess risk was observed among former and current smokers with a greater risk in current smokers. Subgroup analysis showed that the increased risk appeared to be consistent regardless of several study characteristics with the RRs ranging from 1.31 to 1.94 for all-cause mortality, 1.37 to 2.28 for CHD, 1.21 to 1.87 for stroke, 1.13 to 1.74 for cardiovascular mortality and 1.15 to 2.01 for MI.

CONCLUSION

Smoking amplified the risk of mortality as well as cardiovascular events and the effect size for CHD appeared to be higher than other events in diabetic patients. Moreover, a trend of decreasing risk was observed among smoking quitters.

A look into the future: improving diabetes care by 2015

Insulin initiation, which was traditionally the province of specialists, is increasingly undertaken by primary care. However, significant barriers to appropriate and timely initiation still exist. Whilst insulin is recognized as providing the most effective treatment in type 2 diabetes, it is also widely considered to be the most challenging and time consuming. This editorial identifies that the organization of existing healthcare services, the challenges faced by patients, and the treatments themselves contribute to suboptimal insulin management. In order to improve future diabetes care, it will be necessary to address all three problem areas: (1) re-think the best use of existing human and financial resources to promote and support patient self-management and adherence to treatment; (2) empower patients to participate more actively in treatment decision making; and (3) improve acceptance, persistence and adherence to therapy by continuing to refine insulin therapy and treatment regimens in terms of safety, simplicity and convenience. The principles discussed are also applicable to the successful management of any chronic medical illness.

Glycemic control, complications, and death in older diabetic patients: the diabetes and aging study

OBJECTIVE

To identify the range of glycemic levels associated with the lowest rates of complications and mortality in older diabetic patients.

RESEARCH DESIGN AND METHODS

We conducted a retrospective cohort study (2004-2008) of 71,092 patients with type 2 diabetes, aged ≥60 years, enrolled in Kaiser Permanente Northern California. We specified Cox proportional hazards models to evaluate the relationships between baseline glycated hemoglobin (A1C) and subsequent outcomes (nonfatal complications [acute metabolic, microvascular, and cardiovascular events] and mortality).

RESULTS

The cohort (aged 71.0 ± 7.4 years [means ± SD]) had a mean A1C of 7.0 ± 1.2%. The risk of any nonfatal complication rose monotonically for levels of A1C >6.0% (e.g., adjusted hazard ratio 1.09 [95% CI 1.02-1.16] for A1C 6.0-6.9% and 1.86 [1.63-2.13] for A1C ≥11.0%). Mortality had a U-shaped relationship with A1C. Compared with the risk with A1C <6.0%, mortality risk was lower for A1C levels between 6.0 and 9.0% (e.g., 0.83 [0.76-0.90] for A1C 7.0-7.9%) and higher at A1C ≥11.0% (1.31 [1.09-1.57]). Risk of any end point (complication or death) became significantly higher at A1C ≥8.0%. Patterns generally were consistent across age-groups (60-69, 70-79, and ≥80 years).

CONCLUSIONS

Observed relationships between A1C and combined end points support setting a target of A1C <8.0% for older patients, with the caution that A1Cs <6.0% were associated with increased mortality risk. Additional research is needed to evaluate the low A1C-mortality relationship, as well as protocols for individualizing diabetes care.