Cigarette smoking increases the risk of albuminuria among subjects with type I diabetes

Estimating the association between cigarette and e-cigarette use patterns and SARS-CoV-2 negative conversion time: retrospective online survey in China

BACKGROUND

Cigarette smoking has been reported to be associated with SARS-CoV-2 negative conversion, while little is known about the effect of its dual use with e-cigarettes. This study aimed to investigate whether tobacco product use patterns including e-cigarette use were linked with delayed negative conversion of SARS-CoV-2.

METHODS

An online national survey was conducted from January 28 through February 21, 2023, targeting a community-based population in mainland of China after peak waves of the coronavirus disease 2019 (COVID-19). Participants were followed from the onset of COVID-19 symptoms until the negative conversion day or the day of answering the questionnaire as the endpoint of the study. Multi-variable adjusted Cox proportional hazard models were used to compare the negative conversion time of SARS-CoV-2 across different cigarette and e-cigarette use patterns.

RESULTS

A total of 66,537 participants infected with COVID-19 were enrolled and 13,294 were included in the analyses. During the median duration of 7 days (interquartile range 5 to 10 days), a total of 11,587 (87.2%) had a negative conversion. Compared with never users, current exclusive smokers (multi-variable adjusted HR 0.59, 95% CI 0.48-0.71), current dual users (HR 0.31, 95% CI 0.22-0.44), and previous smokers (HR 0.56, 95% CI 0.37-0.83) took longer to turn negative after 10 days of follow-up.

CONCLUSIONS

Both current exclusive cigarette use and dual use of cigarettes and e-cigarettes were associated with the delayed negative conversion of SARS-CoV-2, which strengthens the importance of smoking and vaping cessation messaging and community-based tobacco control strategies during pandemics like COVID-19 next time.

High mobility group box 1 (HMGB1) mediates nicotine-induced podocyte injury

Introduction

Cigarette smoking is a well-established risk factor for renal dysfunction. Smoking associated with renal damage bears distinct physiological correlations in conditions such as diabetic nephropathy and obesity-induced glomerulopathy. However, the cellular and molecular basis of such an association remains poorly understood. High mobility group box 1(HMGB1) is a highly conserved non-histone chromatin associated protein that largely contributes to the pathogenesis of chronic inflammatory and autoimmune diseases such as sepsis, atherosclerosis, and chronic kidney diseases. Hence, the present study tested whether HMGB1 contributes to nicotine-induced podocyte injury.

Methods and Results

Biochemical analysis showed that nicotine treatment significantly increased the HMGB1 expression and release compared to vehicle treated podocytes. However, prior treatment with glycyrrhizin (Gly), a HMGB1 binder, abolished the nicotine-induced HMGB1 expression and release in podocytes. Furthermore, immunofluorescent analysis showed that nicotine treatment significantly decreased the expression of podocyte functional proteins- podocin and nephrin as compared to control cells. However, prior treatment with Gly attenuated the nicotine-induced nephrin and podocin reduction. In addition, nicotine treatment significantly increased desmin expression and cell permeability compared to vehicle treated podocytes. However, prior treatment with Gly attenuated the nicotine-induced desmin expression and cell permeability. Mechanistic elucidation revealed that nicotine treatment augmented the expression of toll like receptor 4 (TLR4) and pre-treatment with Gly abolished nicotine induced TLR4 upregulation. Pharmacological inhibition of TLR4 with Resatorvid, a TLR4 specific inhibitor, also attenuated nicotine induced podocyte damage.

Conclusion

HMGB1 is one of the important mediators of nicotine-induced podocyte injury through TLR4 activation.

Using Risk Assessment to Improve Screening for Albuminuria among US Adults without Diabetes

BACKGROUND

Guidelines currently recommend annual screening for albuminuria only among persons with diabetes mellitus (DM). There is no guidance about albuminuria screening in those with other important risk factors for chronic kidney disease (CKD), such as hypertension and/or family history of kidney disease. We sought to create a risk score that predicts the likelihood of albuminuria in adults without diabetes to prompt earlier detection and management of CKD.

METHODS

Data from 44,322 participants without diabetes, aged 18 + years from the National Health and Nutrition Examination Surveys 1999-2020 were analyzed. Survey-weighted logistic regression was used to assess associations between individual characteristics and presence of albuminuria (urinary albumin to creatinine ratio [UACR] ≥ 30 mg/g), including interaction terms, in three separate models. The sample was divided equally into development and validation data sets. C-statistics were used to assess model fit.

RESULTS

The prevalence of albuminuria was 9.7% in the US adult population. Higher odds of albuminuria among the non-diabetic population were observed in females, non-Hispanic Black, and smokers, as well as those with low eGFR, hypertension, cardiovascular disease, prediabetes, low HDL cholesterol, and high uric acid levels. Age showed a J-shaped relationship with albuminuria, with lowest odds for ages 25-64 years. The C-statistic was 0.756 for the developmental and 0.752 for the validation set of the final model. Using this model, screening individuals with a predicted probability of ≥ 5% would capture 85% of individuals with albuminuria.

CONCLUSIONS

These results suggest that it may be helpful to use a risk score framework for albuminuria screening in people without DM to encourage earlier detection and management of CKD. Longitudinal studies are warranted to confirm this approach along with evaluation of its cost effectiveness.

The Association of Smoking Status with Diabetic Microvascular Complications in Korean Patients with Type 2 Diabetes

PURPOSE

Few studies have investigated the association between smoking and microvascular complications in the Asian population with type 2 diabetes mellitus (T2DM). We aimed to investigate the relationship between smoking status and microvascular complications in Korean patients with T2DM.

MATERIALS AND METHODS

From the Korean National Diabetes Program cohort, we included 2316 Korean male with T2DM who had baseline clinical information available, including their smoking status, and underwent diabetic complication studies.

RESULTS

Compared to non-smokers, current smokers had higher odds of any-microvascular complications [adjusted odds ratio (aOR) 1.45, 95% confidence interval (CI) 1.07-1.97, p=0.016]. The odds of neuropathy were significantly higher; however, the odds of retinopathy were significantly lower in current smokers than in nonsmokers (all p<0.05). Among those who underwent repeated complication tests after 3 years, the risk of newly developed retinopathy was significantly increased in ex-smokers [aOR 3.77 (95% CI 1.61-8.87), p=0.002]. Within ex-smokers, long smoking duration and smoking cessation within the recent 5 years were associated with an increased risk of newly developed retinopathy (all p<0.05).

CONCLUSION

Male smokers had higher odds of having overall diabetic microvascular complications, including neuropathy. However, the odds of having retinopathy were significantly lower among current smokers. More attention and research are needed regarding the increased risk of retinopathy development in ex-smokers who have recently stopped smoking after a long history of smoking.

Epidemiology of tobacco use in dialysis patients in France and survey of nephrologists' involvement in counseling on tobacco discontinuation

BACKGROUND

Tobacco smoking is an independent risk factor for chronic kidney disease (CKD) and increases morbidity and mortality in CKD patients. The primary objective of the study was to investigate the epidemiology of smoking in patients undergoing maintenance dialysis in France. A second objective was to assess the involvement of nephrologists in supporting patients for smoking cessation.

METHODS

Data on the smoking history of prevalent patients on maintenance dialysis in France between 2010 and 2020 were obtained from the REIN database (Renal Epidemiology and Information Network), updated by all French nephrology and dialysis centers. As for the support to smoking discontinuation, a questionnaire on smoking cessation assistance was sent to all members of the French Society of Nephrology, Dialysis and Transplantation (SFNDT).

RESULTS

The proportion of current smokers among patients on maintenance dialysis was 10.4% in 2010, 11.2% in 2015 and 11.6% in 2020. A total of 228 nephrologists among the 790 members of the SFNDT participated in the survey (28.9%). Most respondents were women (57.3%), worked at a public hospital (61.1%), were under 40 years of age (51.3%) and had no history of smoking (60.8%). The majority reported asking patients about their smoking status and offering brief advice. Among respondents, 72.8% offered help with smoking cessation, 46.3% referred their smoking patients to a tobacco specialist, 51.8% reported prescribing drugs to quit tobacco, and 81.6% requested further training in how to support patients for smoking cessation.

CONCLUSION

Smoking cessation training for nephrologists and dedicated programs for patients in nephrology units could improve our practices and decrease the high prevalence of smoking in patients with ESKD.

Development of a risk prediction score and equation for chronic kidney disease: a retrospective cohort study

Chronic kidney disease (CKD) is a risk factor for end-stage renal disease and contributes to increased risk of cardiovascular disease morbidity and mortality. We aimed to develop a risk prediction score and equation for future CKD using health checkup data. This study included 58,423 Japanese participants aged 30-69 years, who were randomly assigned to derivation and validation cohorts at a ratio of 2:1. The predictors were anthropometric indices, life style, and blood sampling data. In derivation cohort, we performed multivariable logistic regression analysis and obtained the standardized beta coefficient of each factor that was significantly associated with new-onset CKD and assigned scores to each factor. We created a score and an equation to predict CKD after 5 years and applied them to validation cohort to assess their reproducibility. The risk score ranged 0-16, consisting of age, sex, hypertension, dyslipidemia, diabetes, hyperuricemia, and estimated glomerular filtration rate (eGFR), with area under the curve (AUC) of 0.78 for the derivation cohort and 0.79 for the validation cohort. The CKD incidence gradually and constantly increased as the score increased from ≤ 6 to ≥ 14. The equation consisted of the seven indices described above, with AUC of 0.88 for the derivation cohort and 0.89 for the validation cohort. We developed a risk score and equation to predict CKD incidence after 5 years in Japanese population under 70 years of age. These models had reasonably high predictivity, and their reproducibility was confirmed through internal validation.

Brain Energy Metabolism in Ischemic Stroke: Effects of Smoking and Diabetes

Proper regulation of energy metabolism in the brain is crucial for maintaining brain activity in physiological and different pathophysiological conditions. Ischemic stroke has a complex pathophysiology which includes perturbations in the brain energy metabolism processes which can contribute to worsening of brain injury and stroke outcome. Smoking and diabetes are common risk factors and comorbid conditions for ischemic stroke which have also been associated with disruptions in brain energy metabolism. Simultaneous presence of these conditions may further alter energy metabolism in the brain leading to a poor clinical prognosis after an ischemic stroke event. In this review, we discuss the possible effects of smoking and/or diabetes on brain glucose utilization and mitochondrial energy metabolism which, when present concurrently, may exacerbate energy metabolism in the ischemic brain. More research is needed to investigate brain glucose utilization and mitochondrial oxidative metabolism in ischemic stroke in the presence of smoking and/or diabetes, which would provide further insights on the pathophysiology of these comorbid conditions and facilitate the development of therapeutic interventions.

Tobacco use patterns and clinical outcomes in the T1D exchange

AIMS

This study examined associations between tobacco use and diabetes outcomes using the T1D Exchange Registry.

METHODS

Adult participants (N = 933) completed standardized questionnaires including self-reported outcomes: past year serious hypoglycemic and diabetic ketoacidosis episodes, diabetes self-care, diabetes distress, and self-monitoring of blood glucose. Chart-extracted outcomes included HbA1c, nephrology and neuropathy diagnoses, and BMI. We examined the relation of tobacco use status (never, former, current) and frequency of use (daily versus less than daily) to these outcomes.

RESULTS

The majority had never used tobacco (55%, n = 515); 27% (n = 252) were former users and 18% (n = 166) were current users (with 31% using daily). Tobacco status was associated with HbA1c, BMI, self-care, distress, and blood glucose monitoring frequency. Across most outcomes, current users evidenced worse values relative to never users, and former users were largely similar to never users. Daily use was associated with significantly worse outcomes on HbA1c, diabetes self-care, and distress scores relative to less than daily use.

CONCLUSIONS

These cross-sectional comparisons suggest that current tobacco use is associated with worse status on important clinical diabetes indicators. Former users did not evidence these deleterious associations. Findings point to potential diabetes-specific motivators that could inform tobacco cessation interventions.

Chronic Kidney Disease and Cerebrovascular Disease: Consensus and Guidance From a KDIGO Controversies Conference

The global health burden of chronic kidney disease is rapidly rising, and chronic kidney disease is an important risk factor for cerebrovascular disease. Proposed underlying mechanisms for this relationship include shared traditional risk factors such as hypertension and diabetes, uremia-related nontraditional risk factors, such as oxidative stress and abnormal calcium-phosphorus metabolism, and dialysis-specific factors such as cerebral hypoperfusion and changes in cardiac structure. Chronic kidney disease frequently complicates routine stroke risk prediction, diagnosis, management, and prevention. It is also associated with worse stroke severity, outcomes and a high burden of silent cerebrovascular disease, and vascular cognitive impairment. Here, we present a summary of the epidemiology, pathophysiology, diagnosis, and treatment of cerebrovascular disease in chronic kidney disease from the Kidney Disease: Improving Global Outcomes Controversies Conference on central and peripheral arterial disease with a focus on knowledge gaps, areas of controversy, and priorities for research.

The Nephrologist's Management of Renal Cell Carcinoma After Kidney Surgery

Renal cell carcinoma is associated with chronic kidney disease as well as with common risk factors including hypertension and diabetes mellitus. Localized renal cell carcinoma is treated surgically and in these cases has a favorable prognosis. In particular, in those individuals with small renal masses (≤4 cm), preservation of kidney function should be prioritized. Postoperative chronic kidney disease or end-stage renal disease prevention should include baseline kidney function and risk factor assessment, nontumor renal biopsy, as well as counseling on treatment options to discuss maximizing kidney function preservation. Postnephrectomy prognosis can be determined with repeat laboratory and clinical assessment. Ultimately, early involvement of the nephrologist in a multidisciplinary team including the urology team will enable the reduction of postsurgical kidney disease related morbidity and potentially mortality.

Nicotine, smoking, podocytes, and diabetic nephropathy

Diabetic nephropathy (DN) is the leading cause of end-stage kidney disease. Besides glycemic and blood pressure control, environmental factors such as cigarette smoking (CS) adversely affect the progression of DN. The effects of CS on DN progression have been attributed to combustion-generated molecules without consideration to the role of nicotine (NIC), responsible for the addictive properties of both CS and electronic cigarettes (ECs). Podocytes are essential to preserve the structure and function of the glomerular filtration barrier, and strong evidence indicates that early podocyte loss promotes DN progression. We performed experiments in human podocytes and in a mouse model of diabetes that develops nephropathy resembling human DN. We determined that NIC binding to podocytes in concentrations achieved with CS and ECs activated NADPH oxidase, which sets in motion a dysfunctional molecular network integrated by cyclooxygenase 2, known to induce podocyte injury; downregulation of AMP-activated protein kinase, important for maintaining cellular energy stores and antioxidation; and upregulation of CD36, which increased lipid uptake and promoted apoptosis. In diabetic mice, NIC increased proteinuria, a recognized marker of chronic kidney disease progression, accompanied by reduced glomerular podocyte synaptopodin, a crucial stabilizer of the podocyte cytoskeleton, and increased fibronectin expression. This novel study critically implicates NIC itself as a contributor to DN progression in CS and EC users.NEW & NOTEWORTHY In this study, we demonstrate that nicotine increases the production of reactive oxygen species, increases cyclooxygenase-2 expression, and upregulates Cd36 while inducing downregulation of AMP-activated protein kinase. In vivo nicotine increases proteinuria and fibronectin expression in diabetic mice. This study demonstrates that effects of nicotine on podocytes are responsible, at least in part, for the deleterious effects of smoking in the progression of chronic kidney disease, including diabetic nephropathy.

Nicotine' actions on energy balance: Friend or foe?

Obesity has reached pandemic proportions and is associated with severe comorbidities, such as type 2 diabetes mellitus, hepatic and cardiovascular diseases, and certain cancer types. However, the therapeutic options to treat obesity are limited. Extensive epidemiological studies have shown a strong relationship between smoking and body weight, with non-smokers weighing more than smokers at any age. Increased body weight after smoking cessation is a major factor that interferes with their attempts to quit smoking. Numerous controlled studies in both humans and rodents have reported that nicotine, the main bioactive component of tobacco, exerts a marked anorectic action. Furthermore, nicotine is also known to modulate energy expenditure, by regulating the thermogenic activity of brown adipose tissue (BAT) and the browning of white adipose tissue (WAT), as well as glucose homeostasis. Many of these actions occur at central level, by controlling the activity of hypothalamic neuropeptide systems such as proopiomelanocortin (POMC), or energy sensors such as AMP-activated protein kinase (AMPK). However, direct impact of nicotine on metabolic tissues, such as BAT, WAT, liver and pancreas has also been described. Here, we review the actions of nicotine on energy balance. The relevance of this interaction is interesting, because considering the restricted efficiency of obesity treatments, a possible complementary approach may focus on compounds with known pharmacokinetic profile and pharmacological actions, such as nicotine or nicotinic acetylcholine receptors signaling.

Undertreatment of cardiovascular risk factors in the type 1 diabetes exchange clinic network (United States) and the prospective diabetes follow-up (Germany/Austria) registries

AIM

To examine the control of cardiovascular risk factors in type 1 diabetes (T1D) registries from the United States and Germany/Austria.

MATERIALS AND METHODS

Data on individuals aged ≥12 years with T1D for ≥1 year, from the T1D Exchange Clinic Network (T1DX, United States) and the Prospective Diabetes Follow-up Registry (DPV, Germany/Austria) from 1 January 2016 to 31 March 2018 were analysed. Linear and logistic regression models adjusted for age groups, sex, duration of diabetes and minority status were used to compare clinical characteristics and achievement of diabetes management targets between registries.

RESULTS

The cohort consisted of 47 936 patients (T1DX, n = 19 442; DPV, n = 28 494). Achievement of HbA1c goals (<7.0%, ages 18-65 years; all others, <7.5%) was better in the DPV for those aged <65 years (all P < .001). However, more older adults (aged ≥65 years) in the T1DX achieved an HbA1c goal of <7.5% compared with DPV (70% vs. 50%, P < .001). The frequency of patients with overweight (53% vs. 51%, P < .001) and obesity (19% vs. 9%, P < .001) was higher in T1DX. The frequency of meeting blood pressure goals (84% vs. 66%, P < .001) and lipid goals (73% vs. 62%, P < .001) was higher in T1DX; this was observed across all age groups (all P < .001). Few young adults aged <26 years received antihypertensive and lipid-lowering medications, respectively, despite indications in both registries (T1DX: 5% and 3%, DPV: 3% and 1%).

CONCLUSION

A minority of patients with T1D achieve glycaemic targets and the majority are inadequately treated for hypertension and dyslipidaemia. This highlights the need for improved diabetes and cardiovascular risk management strategies in T1D.

Smoking and risk of incident end-stage kidney disease in general population: A Nationwide Population-based Cohort Study from Korea

We analyzed data from the Korean National Health Insurance Service (NHIS) to investigate whether smoking increases the risk of end-stage kidney disease (ESKD). This retrospective nationwide population-based cohort study included the data of 23,232,091 participants who underwent at least one health examination between 2009 and 2012. Smoking status was recorded at baseline. The incidence of ESKD was identified via ICD-10 codes and special medical aid codes from the Korean National Health Insurance Service database till December 2016. A Cox proportional-hazards model with multivariable adjustment was used to evaluate the association between smoking and ESKD incidence. Overall, 24.6% of participants were current smokers; 13.5% and 61.9%, were ex- and non-smokers, respectively. Overall, 45,143 cases of ESKD developed during the follow-up period. Current smokers (hazard ratio [HR], 1.39; 95% confidence interval [CI], 1.35-1.43) and ex-smokers (HR, 1.09; 95% CI, 1.06-1.12) demonstrated a significant increase in the adjusted risk of ESKD compared to non-smokers. The risk of ESKD was directly proportional to the smoking duration, number of cigarettes smoked daily, and pack-years. In conclusion, smoking is associated with a greater risk of ESKD in the general Korean population; the risk increases with an increase in the smoking duration, number of cigarettes smoked daily, and pack-years.

Brain-to-pancreas signalling axis links nicotine and diabetes

The discovery of a signalling axis that connects nicotine responses in the brain with glucose metabolism by the pancreas sheds light on why cigarette smoking increases the risk of diabetes.

Association of smoking and cardiometabolic parameters with albuminuria in people with type 2 diabetes mellitus: a systematic review and meta-analysis

AIMS

Smoking is a strong risk factor for albuminuria in people with type 2 diabetes mellitus (T2DM). However, it is unclear whether this sequela of smoking is brought about by its action on cardiometabolic parameters or the relationship is independent. The aim of this systematic review is to explore this relationship.

METHODS

Electronic databases on cross-sectional and prospective studies in Medline and Embase were searched from January 1946 to May 2018. Adult smokers with T2DM were included, and other types of diabetes were excluded.

RESULTS

A random effects meta-analysis of 20,056 participants from 13 studies found that the odds ratio (OR) of smokers developing albuminuria compared to non-smokers was 2.13 (95% CI 1.32, 3.45). Apart from smoking, the odds ratio of other risk factors associated with albuminuria were: age 1.24 (95% CI 0.84, 1.64), male sex 1.39 (95% CI 1.16, 1.67), duration of diabetes 1.78 (95% CI 1.32, 2.23), HbA1c 0.63 (95% CI 0.45, 0.81), SBP 6.03 (95% CI 4.10, 7.97), DBP 1.85 (95% CI 1.08, 2.62), total cholesterol 0.06 (95% CI - 0.05, 0.17) and HDL cholesterol - 0.01 (95% CI - 0.04, 0.02), triglyceride 0.22 (95% CI 0.12, 0.33) and BMI 0.40 (95% CI 0.00-0.80). When the smoking status was adjusted in a mixed effect meta-regression model, the duration of diabetes was the only statistically significant factor that influenced the prevalence of albuminuria. In smokers, each year's increase in the duration of T2DM was associated with an increased risk of albuminuria of 0.19 units (95% CI 0.07, 0.31) on the log odds scale or increased the odds approximately by 23%, compared to non-smokers. Prediction from the meta-regression model also suggested that the odds ratios of albuminuria in smokers after a diabetes duration of 9 years and 16 years were 1.53 (95% CI 1.10, 2.13) and 5.94 (95% CI 2.53, 13.95), respectively.

CONCLUSIONS

Continuing to smoke and the duration of diabetes are two strong predictors of albuminuria in smokers with T2DM. With a global surge in younger smokers developing T2DM, smoking cessation interventions at an early stage of disease trajectory should be promoted.

Mediation of the association of smoking and microvascular complications by glycemic control in type 1 diabetes

Studies have demonstrated the adverse effects of smoking on the risk of microvascular complications; however, few have also examined the potential mediating effects of glycemic control. Using data from the Diabetes Control and Complications Trial (DCCT 1983–1993), we describe the acute and long-term risks of smoking on glycemic control and microvascular complications in a well-characterized cohort of participants with type 1 diabetes. The DCCT recorded self-reported smoking behaviors, glycemic exposure based on HbA1c, and complications status. Generalized linear mixed models were used to assess whether time-dependent measurements of smoking predict HbA1c levels. Cox proportional hazard models were used to assess time-dependent smoking exposures as predictors of retinopathy and nephropathy. During a mean of 6.5 years of follow-up, current smokers had consistently higher HbA1c values and were at a higher risk of retinopathy and nephropathy compared with former and never smokers. These risk differences were attenuated after adjusting for HbA1c suggesting that the negative association of smoking on glycemic control is partially responsible for the adverse association of smoking on the risk of complications in type 1 diabetes. These findings support the potential for a beneficial effect of smoking cessation on complications in type 1 diabetes.

Air pollution and kidney disease: review of current evidence

Along with amazing technological advances, the industrial revolution of the mid-19th century introduced new sources of pollution. By the mid-20th century, the effects of these changes were beginning to be felt around the world. Among these changes, health problems due to environmental air pollution are increasingly recognized. At the beginning, respiratory and cardiovascular diseases were emphasized. However, accumulated data indicate that every organ system in the body may be involved, and the kidney is no exception. Although research on air pollution and kidney damage is recent, there is now scientific evidence that air pollution harms the kidney. In this holistic review, we have summarized the epidemiology, disease states and mechanisms of air pollution and kidney damage.

Gender differences in diabetes self-care in adults with type 1 diabetes: Findings from the T1D Exchange clinic registry

AIMS

To evaluate gender differences in diabetes self-care components including glycemic, blood pressure and lipid control, utilization of diabetes technologies and acute diabetes complications in adults with type 1 diabetes.

METHODS

A total of 9,481 participants >18 years were included in the analysis, 53% were female. Variables of interest included glycemic control measured by HbA1c, systolic/diastolic blood pressures, presence of dyslipidemia, insulin delivery modality, and rates of acute complications.

RESULTS

Glycemic control was similar in women and men (mean HbA1c in both groups: 8.1% ± 1.6% (64 ± 16 mmol/mol), (p = 0.54). More women used insulin pump therapy (66% vs. 59%, p < 0.001) but use of sensor technology was similar (p < = 0.42). Women had higher rates of diabetic ketoacidosis (DKA) (5% vs. 3%, p < 0.001) and eating disorders (1.7% vs. 0.1%, p < 0.001). Severe hypoglycemia rates were not different between men and women (p = 0.42). Smoking (6% vs 4%, p < 0.001), systolic (125 ± 14.2 vs. 121 ± 14.4, p < 0.001) and diastolic blood pressure (73.3 ± 9.5 vs. 72.2 ± 9.3, p < 0.001) and rate of dyslipidemia (28% vs. 23%, p < 0.001) were higher in men.

CONCLUSION

While glycemic control in type 1 diabetes was similar regardless of gender, rates of DKA and eating disorders were higher in women while rates of smoking, hypertension and dyslipidemia were higher in men.

Review of biomarkers to assess the effects of switching from cigarettes to modified risk tobacco products

Context: One approach to reducing the harm caused by cigarette smoking, at both individual and population level, is to develop, assess and commercialize modified risk alternatives that adult smokers can switch to. Studies to demonstrate the exposure and risk reduction potential of such products generally involve the measuring of biomarkers, of both exposure and effect, sampled in various biological matrices.Objective: In this review, we detail the pros and cons for using several biomarkers as indicators of effects of changing from conventional cigarettes to modified risk products.Materials and methods: English language publications between 2008 and 2017 were retrieved from PubMed using the same search criteria for each of the 25 assessed biomarkers. Nine exclusion criteria were applied to exclude non-relevant publications.Results: A total of 8876 articles were retrieved (of which 7476 were excluded according to the exclusion criteria). The literature indicates that not all assessed biomarkers return to baseline levels following smoking cessation during the study periods but that nine had potential for use in medium to long-term studies.Discussion and conclusion: In clinical studies, it is important to choose biomarkers that show the biological effect of cessation within the duration of the study.

Latent profile analysis of lifestyle characteristics and health risk behaviors among Koreans who have completed industrial accident care

This study investigated the characteristics and health behavior profiles of 1,803 workers who had experienced industrial accidents. Average weekly exercise days, average number of cigarettes smoked per day, average daily sleep duration, and number of days of alcohol consumption were selected to investigate health behavior profiles. Specifically, latent profile analysis was applied to identify the health behavior profiles of people who had completed industrial accident care; the latent classes were the health-conscious type (n=240), the potential-risk type (n=850), and the high-risk type (n=713). Comparison of the health-conscious and potential-risk types indicated that younger subjects, the employed, and those with lower social status and life satisfaction were more likely to be the potential-risk type. Comparison of the health-conscious and high-risk types revealed that males, younger subjects, the employed, those without chronic illnesses, and those with lower social status and life satisfaction were more likely to be the high-risk type. The results suggest that industrial accident victims who have completed accident care have different health behaviors and it is necessary to improve health promotion based on health type characteristics.

Cigarette Smoking and Its Hazards in Kidney Transplantation

Cigarette smoking affects many organs. It causes vasoconstriction through activation of sympathetic nervous system which leads to elevation of blood pressure and reduction in glomerular filtration rate and filtration pressure. It also causes thickening of renal arterioles. Cigarette smoking increases the risk of microalbuminuria and accelerates progression of microalbuminuria to macroalbuminuria. Furthermore, it causes rapid loss of glomerular filtration rate in chronic kidney disease patients. After kidney donation, these factors may be injurious to the solitary kidney. Kidney donors with history of cigarette smoking are prone to develop perioperative complications, pneumonia, and wound infection. Postkidney transplantation various stressors including warm and cold ischemia time, delayed graft function, and exposure to calcineurin inhibitors may result in poor graft function. Continuation of cigarette smoking in kidney transplant recipients will add further risk. In this review, we will specifically discuss the effects of cigarette smoking on normal kidneys, live kidney donors, and kidney transplant recipients. This will include adverse effects of cigarette smoking on graft and patient survival, cardiovascular events, rejection, infections, and cancers in kidney transplant recipients. Lastly, the impact of kidney transplantation on behavior and smoking cessation will also be discussed.

Smoking and progression of diabetic nephropathy in patients with type 1 diabetes

AIMS

To evaluate the effect of cumulative smoking on the development of diabetic nephropathy.

METHODS

Study included 3613 patients with type 1 diabetes, participating in the Finnish Diabetic Nephropathy Study. The 12-year cumulative risk of microalbuminuria, macroalbuminuria and end-stage renal disease (ESRD) was estimated for current, ex- and nonsmokers. Cox regression analyses, with multivariable adjustments for other risk factors for diabetic nephropathy, were used to evaluate the risk at different stages of diabetic nephropathy based on the cumulative amount of smoking in pack-years.

RESULTS

The 12-year cumulative risk of microalbuminuria was 18.9 % (95 % CI 14.6-23.0, P < 0.0001) for current smokers and 15.1 % (10.3-19.6, P = 0.087) for ex-smokers, compared with 10.0 % (7.8-12.1) for nonsmokers. The corresponding risks of macroalbuminuria were 14.4 % (95 % CI 10.8-17.9, P < 0.0001), 6.1 % (3.5-8.6, P = 0.082) and 4.7 % (3.0-6.4), respectively. The 12-year cumulative risk of ESRD was 10.3 % (95 % CI 8.4-12.4, P < 0.0001) for current smokers and 10.0 % (7.9-12.3, P < 0.0001) for ex-smokers, compared with 5.6 % (4.6-6.7) for nonsmokers. In the current smokers, one pack-year increased the risk of macroalbuminuria with a HR of 1.025 (1.010-1.041) and the risk of ESRD with a HR of 1.014 (1.001-1.026) compared with nonsmokers, in the fully adjusted model. In the ex-smokers, the risk of macroalbuminuria and ESRD was no different from the risk in nonsmokers after multivariable adjustment.

CONCLUSIONS

Current smoking is a risk factor for the progression of diabetic nephropathy and the risk increases with the increasing dose of smoking. Ex-smokers seem to carry a similar risk of progression of diabetic nephropathy as nonsmokers.

Smoking and Adverse Outcomes in Patients With CKD: The Study of Heart and Renal Protection (SHARP)

Background

The absolute and relative importance of smoking to vascular and nonvascular outcomes in people with chronic kidney disease (CKD), as well its relevance to kidney disease progression, is uncertain.

Study Design

Observational study.

Setting & Participants

9,270 participants with CKD enrolled in SHARP.

Predictor

Baseline smoking status (current, former, and never).

Outcomes

Vascular events, site-specific cancer, ESRD, rate of change in estimated glomerular filtration rate (eGFR), and cause-specific mortality.

Results

At baseline, 1,243 (13%) participants were current smokers (median consumption, 10 cigarettes/day); 3,272 (35%), former smokers; and 4,755 (51%), never smokers. Median follow-up was 4.9 years. Vascular event rates were 36% higher for current than never smokers (2,317 events; relative risk [RR], 1.36; 95% CI, 1.19-1.55), reflecting increases in both atherosclerotic (RR, 1.49; 95% CI, 1.26-1.76) and nonatherosclerotic (RR, 1.25; 95% CI, 1.05-1.50) events. Cancer was 37% higher among current smokers (632 events; RR, 1.37; 95% CI, 1.07-1.76), with the biggest RRs for lung (RR, 9.31; 95% CI, 4.37-19.83) and upper aerodigestive tract (RR, 4.87; 95% CI, 2.10-11.32) cancers. For 6,245 patients not receiving dialysis at baseline, ESRD incidence did not differ significantly between current and never smokers (2,141 events; RR, 1.02; 95% CI, 0.89-1.17), nor did estimated rate of change in eGFR (current smokers, −1.77 ± 0.14 [SE]; never smokers, −1.70 ± 0.07 mL/min/1.73 m² per year). All-cause mortality was 48% higher among current smokers (2,257 events; RR, 1.48; 95% CI, 1.30-1.70), with significant increases in vascular (RR, 1.35; 95% CI, 1.07-1.69) and nonvascular (RR, 1.60; 95% CI, 1.34-1.91) causes of death, especially cancer (RR, 2.32; 95% CI, 1.58-3.40) and respiratory (RR, 2.25; 95% CI, 1.51-3.35) mortality.

Limitations

Smoking status not assessed during follow-up.

Conclusions

In this study of patients with CKD, smoking significantly increased the risks for vascular and nonvascular morbidity and mortality, but was not associated with kidney disease progression. The associations with vascular and neoplastic disease are in keeping with those observed in the general population and are likely modifiable by cessation.

Impact of Lifestyle Modification on Diabetic Kidney Disease

Kidney disease is common in patients with type 1 and type 2 diabetes mellitus and is associated with adverse health outcomes, including progression to end-stage renal disease. In the general population, adherence to a healthy lifestyle is known to reduce the risk of cardiovascular events and death. Among individuals with diabetic kidney disease, modifications in lifestyle factors, including diet, physical activity, smoking habits, and body mass index, represent a promising cost-effective therapeutic adjunct to pharmacologic treatment of kidney disease incidence and progression.

Early chronic kidney disease: diagnosis, management and models of care

Chronic kidney disease (CKD) is prevalent in many countries, and the costs associated with the care of patients with end-stage renal disease (ESRD) are estimated to exceed US$1 trillion globally. The clinical and economic rationale for the design of timely and appropriate health system responses to limit the progression of CKD to ESRD is clear. Clinical care might improve if early-stage CKD with risk of progression to ESRD is differentiated from early-stage CKD that is unlikely to advance. The diagnostic tests that are currently used for CKD exhibit key limitations; therefore, additional research is required to increase awareness of the risk factors for CKD progression. Systems modelling can be used to evaluate the impact of different care models on CKD outcomes and costs. The US Indian Health Service has demonstrated that an integrated, system-wide approach can produce notable benefits on cardiovascular and renal health outcomes. Economic and clinical improvements might, therefore, be possible if CKD is reconceptualized as a part of primary care. This Review discusses which early CKD interventions are appropriate, the optimum time to provide clinical care, and the most suitable model of care to adopt.

Type 2 diabetes and cardiovascular disease: Have all risk factors the same strength?

Diabetes mellitus is a chronic condition that occurs when the body cannot produce enough or effectively use of insulin. Compared with individuals without diabetes, patients with type 2 diabetes mellitus have a considerably higher risk of cardiovascular morbidity and mortality, and are disproportionately affected by cardiovascular disease. Most of this excess risk is it associated with an augmented prevalence of well-known risk factors such as hypertension, dyslipidaemia and obesity in these patients. However the improved cardiovascular disease in type 2 diabetes mellitus patients can not be attributed solely to the higher prevalence of traditional risk factors. Therefore other non-traditional risk factors may be important in people with type 2 diabetes mellitus. Cardiovascular disease is increased in type 2 diabetes mellitus subjects due to a complex combination of various traditional and non-traditional risk factors that have an important role to play in the beginning and the evolution of atherosclerosis over its long natural history from endothelial function to clinical events. Many of these risk factors could be common history for both diabetes mellitus and cardiovascular disease, reinforcing the postulate that both disorders come independently from “common soil”. The objective of this review is to highlight the weight of traditional and non-traditional risk factors for cardiovascular disease in the setting of type 2 diabetes mellitus and discuss their position in the pathogenesis of the excess cardiovascular disease mortality and morbidity in these patients.

Smoking and arterial stiffness in youth with type 1 diabetes: the SEARCH Cardiovascular Disease Study

OBJECTIVE

To evaluate the effects of smoking on early markers of cardiovascular disease (arterial stiffness) in adolescents with and without type 1 diabetes (T1D) in the SEARCH Cardiovascular Disease Study.

STUDY DESIGN

Participants included 606 youth (18.9 ± 3.3 years, 83% non-Hispanic white; 50% male). Six groups were defined: (1) smokers with T1D (n = 80); (2) former smokers with T1D (n = 88); (3) nonsmokers with T1D (n = 232); (4) smokers without T1D (n = 40); (5) former smokers without T1D former (n = 51); and (6) nonsmokers without T1D (n = 115). Arterial stiffness measurements included pulse wave velocity (PWV), augmentation index, and brachial distensibility. Multivariate linear regression was used to assess the independent and joint effects of T1D and smoking on arterial stiffness.

RESULTS

Nearly 20% of both youth with and without T1D and T1D were smokers. In youth without T1D, smokers had higher trunk and arm PWV. After adjustment for potential confounders, T1D, but not smoking, was an independent predictor of PWV (P < .05). Moreover, smoking status did not modify the association between T1D and increased arterial stiffness.

CONCLUSIONS

We found a high prevalence of smoking among youth with and without T1D; however, smoking status was not independently associated with increased arterial stiffness in youth with T1D.

Normoglycemic diabetic nephropathy: the role of insulin resistance

The pathophysiology of diabetic nephropathy (DN) is complex and incompletely understood. Whereas hyperglycemia is clearly important, the role of insulin resistance (IR) is increasingly recognized. We present the case of a normotensive non-smoking obese woman with nephrotic syndrome who was found to have DN by biopsy. All measures of glucose metabolism, including fasting glucose, glycosylated hemoglobin, and oral glucose tolerance testing, were repeatedly normal with little exception. IR was documented, however, based on the presence of the metabolic syndrome and an elevated homeostasis model assessment of IR. We posit that this IR is central to the pathogenesis of our patient's lesion, and this may explain other cases of DN with normoglycemia. The literature supporting this concept is discussed.

Nicotine accelerates diabetes-induced retinal changes

PURPOSE

To investigate the effects of nicotine on retinal alterations in early-stage diabetes in an established rodent model.

MATERIALS AND METHODS

Sprague-Dawley rats were examined using a combination of confocal scanning laser ophthalmoscopy and spectral domain optical coherence tomography to determine changes in retinal structure in response to nicotine exposure, diabetes and the combined effects of nicotine and diabetes. Diabetes was induced by a single injection of 65 mg/kg streptozotocin and nicotine injections were administered subcutaneously daily. Retinal thickness in the superior, inferior, nasal and temporal quadrants were determined based on the spectral domain optical coherence tomography (SD-OCT) volume scans (20° × 20°) centered on the optic disc. Segmentation of discrete retinal layers was performed on a subset of SD-OCT cross-sections to further examine changes in each treatment group. Survival of neurons within the ganglion cell layer (GCL) was assessed by confocal morphometric imaging.

RESULTS

The control group did not experience any significant change throughout the study. The nicotine treatment group experienced an average decrease in total retinal thickness (TRT) of 9.4 µm with the majority of the loss localized within the outer nuclear layer (ONL) as determined by segmentation analysis (p < 0.05). The diabetic group exhibited a trend toward decreased TRT while segmentation analysis of the diabetic retinopathy (DR) group revealed significant thinning within the ONL (p < 0.05). The combination of nicotine and diabetes revealed a significant increase of 8.9 µm in the TRT (p < 0.05) accompanied by a decrease in the number of GCL neurons.

CONCLUSIONS

We demonstrated significant temporal changes in retinal morphology in response to nicotine exposure, diabetes and with the combined effects of nicotine and diabetes. These findings may have implications in determining treatment strategies for diabetic patients using products containing nicotine, such as cigarettes, smokeless tobacco, electronic cigarettes or smoking cessation products.

Prognostic implications of microvascular and macrovascular abnormalities in older adults: cardiovascular health study

BACKGROUND

Microvascular and macrovascular abnormalities are frequently found on noninvasive tests performed in older adults. Their prognostic implications on disability and life expectancy have not been collectively assessed.

METHODS

This prospective study included 2,452 adults (mean age: 79.5 years) with available measures of microvascular (brain, retina, kidney) and macrovascular abnormalities (brain, carotid, coronary, peripheral artery) in the Cardiovascular Health Study. The burden of microvascular and macrovascular abnormalities was examined in relation to total, activity-of-daily-living disability-free, and severe disability-free life expectancies in the next 10 years (1999-2009).

RESULTS

At 75 years, individuals with low burden of both abnormalities lived, on average, 8.71 years (95% confidence interval: 8.29, 9.12) of which 7.67 years (7.16, 8.17) were without disability. In comparison, individuals with high burden of both abnormalities had shortest total life expectancy (6.95 years [6.52, 7.37]; p < .001) and disability-free life expectancy (5.60 years [5.10, 6.11]; p < .001). Although total life expectancy was similarly reduced for those with high burden of either type of abnormalities (microvascular: 7.96 years [7.50, 8.42] vs macrovascular: 8.25 years [7.80, 8.70]; p = .10), microvascular abnormalities seemed to have larger impact than macrovascular abnormalities on disability-free life expectancy (6.45 years [5.90, 6.99] vs 6.96 years [6.43, 7.48]; p = .016). These results were consistent for severe disability-free life expectancy and in individuals without clinical cardiovascular disease.

CONCLUSIONS

Considering both microvascular and macrovascular abnormalities from multiple noninvasive tests may provide additional prognostic information on how older adults spend their remaining life. Optimal clinical use of this information remains to be determined.

Type 1 diabetes and cardiovascular disease

The presence of cardiovascular disease (CVD) in Type 1 diabetes largely impairs life expectancy. Hyperglycemia leading to an increase in oxidative stress is considered to be the key pathophysiological factor of both micro- and macrovascular complications. In Type 1 diabetes, the presence of coronary calcifications is also related to coronary artery disease. Cardiac autonomic neuropathy, which significantly impairs myocardial function and blood flow, also enhances cardiac abnormalities. Also hypoglycemic episodes are considered to adversely influence cardiac performance. Intensive insulin therapy has been demonstrated to reduce the occurrence and progression of both micro- and macrovascular complications. This has been evidenced by the Diabetes Control and Complications Trial (DCCT) / Epidemiology of Diabetes Interventions and Complications (EDIC) study. The concept of a metabolic memory emerged based on the results of the study, which established that intensified insulin therapy is the standard of treatment of Type 1 diabetes. Future therapies may also include glucagon-like peptide (GLP)-based treatment therapies. Pilot studies with GLP-1-analogues have been shown to reduce insulin requirements.

Nicotine signaling and progression of chronic kidney disease in smokers

The deleterious health effects of cigarette smoking are far reaching, and it remains the most important modifiable risk factor for improving overall morbidity and mortality. In addition to being a risk factor for cancer, cardiovascular disease and lung disease, there is strong evidence, both from human and animal studies, demonstrating a role for cigarette smoking in the progression of chronic kidney disease (CKD). Clinical studies have shown a strong correlation between cigarette smoking and worsening CKD in patients with diabetes, hypertension, polycystic kidney disease, and post kidney transplant. Nicotine, in addition to its role in the addictive properties of cigarette smoking, has other biological effects via activation of non-neuronal nicotinic acetylcholine receptors (nAChRs). Several nAChR subunits are expressed in the normal kidney and blockade of the α7-nAChR subunit ameliorates the effects of nicotine in animal models of CKD. Nicotine increases the severity of renal injury in animal models including acute kidney injury, diabetes, acute nephritis and subtotal nephrectomy. The renal effects of nicotine are also linked to increased generation of reactive oxygen species and activation of pro-fibrotic pathways. In humans, nicotine induces transitory increases in blood pressure accompanied by reductions in glomerular filtration rate and effective renal plasma flow. In summary, clinical and experimental evidence indicate that nicotine is at least in part responsible for the deleterious effects of cigarette smoking in the progression of CKD. The mechanisms involved are the subject of active investigation and may result in novel strategies to ameliorate the effects of cigarette smoking in CKD.

Smoking is associated with impaired long-term glucose metabolism in patients with type 1 diabetes mellitus

BACKGROUND AND AIMS

Smoking is known to negatively influence glucose metabolism both in healthy subjects and in patients with diabetes. The aim of this study was to compare glycemic control in patients with type 1 diabetes mellitus who were smokers with those who did not smoke during a prospective long-term follow-up.

METHODS AND RESULTS

In a single center, 763 patients with type 1 diabetes mellitus were included, 160 (21.0%) of them were smokers. Patients were treated with intensive insulin therapy according to existing guidelines. Glucose control was monitored quarterly, diabetes related complications and cardiovascular risk factors were assessed at least once a year. Glucose control in smokers was significantly worse than in non-smokers at baseline and during follow-up (mean HbA1c during 5047 patient-years of follow-up 7.9 ± 1.3% in smokers and 7.3 ± 1.1% in non-smokers, p < 0.001) despite a higher insulin dosage in smokers (0.71 ± 0.30 U/kg vs. 0.65 ± 0.31 U/kg in non-smokers, p = 0.046). HDL cholesterol was lower in smokers at baseline (1.53 ± 0.45 vs. 1.68 ± 0.51 in non-smokers, p = 0.048). Diabetes related complications tended to occur with a higher frequency in smokers, with a significant difference in macroalbuminuria (9.8% vs. 4.8% in non-smokers, p = 0.047).

CONCLUSION

Smoking is associated with worse glucose control in patients with type 1 diabetes mellitus despite the same treatment strategies as in non-smokers. Hyperglycemia, therefore, may contribute to an earlier incidence of diabetes related complications in these patients, in addition to direct toxic effects of smoking.

[Kidney and smoking: literature review and focus]

Smoking remains a major public health problem. It is associated with a considerable number of deaths in the world's population. Smoking is just like high blood pressure, an independent predictor of progression to any primary renal disease and renal transplant patients. It seems that smoking cessation slows the progression of kidney disease in smokers. The literature data are sometimes contradictory about it because of some methodological weaknesses. However, experimental models highlight the harmful effects of tobacco by hemodynamic and non-hemodynamic factors. The conclusion is that a major effort should be further produced by the nephrology community to motivate our patients to stop smoking.

Smoking in diabetic nephropathy: sparks in the fuel tank?

Diabetic nephropathy is associated with high morbidity and mortality and the prevalence of this disease is continuously increasing worldwide. Long-term diabetes increases the likelihood of developing secondary complications like nephropathy, the most common cause of end stage renal disease. Usually, other factors like hypertension, alcoholism and smoking also partly contribute to the progression of diabetic nephropathy. Among this, cigarette smoking in diabetes has been repeatedly confirmed as an independent risk factor for the onset and progression of diabetic nephropathy. Various studies suggest that smoking is a major fuel in the development of high oxidative stress and subsequently hyperlipidemia, accumulation of advanced glycation end products, activation of the renin angiotensin system and Rho-kinase, which are observed to play a pathogenic role in the progression of diabetic nephropathy. Furthermore, cigarette smoking in diabetic patients with vascular complications produces a variety of pathological changes in the kidney, such as thickening of the glomerular basement membrane and mesangial expansion with progression in glomerulosclerosis and interstitial fibrosis, which ultimately results in end stage renal failure. Strong associations are consistently found between chronic cigarette smoking and diabetic microvascular complications. A diverse group of studies unveil potential mechanisms that may explain the role of cigarette smoking in the progression of diabetic nephropathy. Tremendous efforts are being made to control smoking mediated progression of diabetic nephropathy, but no promising therapy is yet available. The present review critically discusses the possible detrimental role of chronic cigarette smoking in the progression of diabetic nephropathy and various possible pharmacological interventions to attenuate the exacerbation of diabetic nephropathy.

Current smoking status may be associated with overt albuminuria in female patients with type 1 diabetes mellitus: a cross-sectional study

BACKGROUND

There are very few clinical reports that have compared the association between cigarette smoking and microangiopathy in Asian patients with type 1 diabetes mellitus (T1DM). The objective of this study was to assess the relationships between urinary protein concentrations and smoking and gender-based risk factors among patients with T1DM.

METHODS

A cross-sectional study of 259 patients with T1DM (men/women = 90/169; mean age, 50.7 years) who visited our hospital for more than 1 year between October 2010 and April 2011 was conducted. Participants completed a questionnaire about their smoking habits. Patient characteristics included gender, age, body mass index, blood pressure, hemoglobin A1c, lipid parameters, and microangiopathy. Diabetic nephropathy (DN) was categorized as normoalbuminuria (NA), microalbuminuria (MA), or overt albuminuria (OA) on the basis of the following urinary albumin/creatinine ratio (ACR) levels: NA, ACR levels less than 30 mg/g creatinine (Cr); MA, ACR levels between 30 and 299 mg/g Cr; and OA, ACR levels over 300 mg/g Cr.

RESULTS

The percentages of current nonsmokers and current smokers with T1DM were 73.0% (n = 189) and 27.0% (n = 70), respectively. In addition, the percentage of males was higher than that of females (52.2% versus 13.6%) in the current smoking population. The percentage of DN was 61.8% (n = 160) in patients with NA, 21.6% (n = 56) in patients with MA, and 16.6% (n = 43) in patients with OA. The percentage of males among OA patients was also higher than that of females (24.4% versus 12.4%). However, current smoking status was associated with OA in females with T1DM only [unadjusted odds ratio (OR), 4.13; 95% confidence interval (CI), 1.45-11.73, P < 0.01; multivariate-adjusted OR, 5.41; 95% CI, 1.69-17.30, P < 0.01].

CONCLUSIONS

Based on our results in this cross-sectional study of Asian patients with T1DM, smoking might be a risk factor for OA among female patients. Further research is needed of these gender-specific results.

Cigarette smoking, proteinuria, and renal function in middle-aged Japanese men from an occupational population

OBJECTIVES

To clarify the renal effects of cigarette smoking in a middle-aged occupational population because the effects have previously been demonstrated mainly in community populations that included many elderly people who are thought to be vulnerable to such effects.

METHODS

In 990 middle-aged men recruited from a chemical plant, proteinuria was measured by a dipstick method and the glomerular filtration rate was estimated (eGFR) using a formula proposed by the Japanese Society of Nephrology.

RESULTS

Proteinuria was found in 4.6% of the current smokers and 1.5% of the never-smokers. It was found in 4.8% of the subjects having a Brinkman index (BI) of 400-599 and 6.3% of those having a BI of 600 or above. The odds ratio for proteinuria in them was 2.94 (CI: 1.01-8.55) and 3.61 (CI: 1.29-10.1), respectively, adjusting for possible confounders. The mean eGFR was higher in smokers than in nonsmokers throughout middle age up to 64 years. Normal but high eGFR was found in 6.7% of the current heavy smokers and subnormal eGFR in 5.7% of the largest cumulative cigarette consumers in contrast to 3.0% or less of the never-smokers. Proteinuria was found in 13.3% of the subjects showing subnormal eGFR, specifically in 16.7% of the smokers and 8.3% of the nonsmokers.

CONCLUSIONS

Smoking causes proteinuria in working middle-aged men. Smokers tend to have a high eGFR, but those with subnormal eGFR showed proteinuria most frequently. Whether the high eGFR in smokers will eventually decrease and cause proteinuria remains an important focus for further studies.

Prevention and treatment of microvascular disease in childhood type 1 diabetes

INTRODUCTION

The incidence of type 1 diabetes (T1D) is increasing worldwide, particularly in children, and is associated with a significant burden, mainly related to the development of vascular complications. The prevention and treatment of microvascular complications, which include nephropathy, retinopathy and neuropathy, are of paramount importance to decrease the associated mortality and morbidity.

SOURCES OF DATA

A literature search was performed on Medline and articles on microvascular complications, with particular emphasis on the increasing incidence of childhood T1D and its implications on prevention and treatment of complications, were selected.

AREAS OF AGREEMENT

The incidence of childhood T1D is increasing. Early identification of subjects at risk for long-term complications and early implementation of preventive and therapeutic strategies are fundamental in order to reduce the burden associated with microvascular complications of diabetes. Improving glycaemic control is the principle way of preventing and treating T1D complications.

AREAS OF CONTROVERSY

In adults with T1D and microvascular complications, treatment with anti-hypertensive drugs and statins is increasingly common, whereas there are no definitive indications for treatment with these drugs in children and adolescents with early signs of complications.

GROWING POINTS

There is growing interest in the development of new preventive and therapeutic strategies targeting specific pathways implicated in the pathogenesis of microvascular complications.

AREAS TIMELY FOR DEVELOPING RESEARCH

Investigations to clarify genetic and environmental factors implicated in the pathogenesis of microvascular complications could lead to the identification of biochemical markers with high predictive values, to be used as a guide for screening and intervention programmes.