Body-Mass Index and All-Cause Mortality in US Adults With and Without Diabetes

Association of systemic immune-inflammation index with all-cause and cardio-cerebrovascular mortality in individuals with diabetic kidney disease: evidence from NHANES 1999-2018

Background

Emerging evidence suggests a potential role of immune response and inflammation in the pathogenesis of diabetic kidney disease (DKD). The systemic immune-inflammation index (SII) offers a comprehensive measure of inflammation; however, its relationship with the prognosis of DKD patients remains unclear.

Methods

Using data from the National Health and Nutrition Examination Survey (NHANES) spanning 1999 to 2018, this cross-sectional study involved adults diagnosed with DKD. Cox proportional hazards models were utilized to assess the associations between SII and all-cause or cardio-cerebrovascular disease mortality. Additionally, restricted cubic spline, piecewise linear regression, and subgroup analyses were performed.

Results

Over a median follow-up duration of 6.16 years, 1338 all-cause deaths were recorded. After adjusting for covariates, elevated SII levels were significantly associated with increased risks of all-cause and cardio-cerebrovascular disease mortality. Specifically, per one-unit increment in natural log-transformed SII (lnSII), there was a 29% increased risk of all-cause mortality (P < 0.001) and a 23% increased risk of cardio-cerebrovascular disease mortality (P = 0.01) in the fully adjusted model. Similar results were observed when SII was analyzed as a categorical variable (quartiles). Moreover, nonlinear association was identified between SII and all-cause mortality (P < 0.001) through restricted cubic spline analysis, with threshold value of 5.82 for lnSII. The robustness of these findings was confirmed in subgroup analyses. Likewise, the statistically significant correlation between SII levels and cardio-cerebrovascular disease mortality persisted in individuals with DKD.

Conclusion

Increased SII levels, whether examined as continuous variables or categorized, demonstrate a significant association with elevated risks of all-cause and cardio-cerebrovascular disease mortality among DKD patients. These findings imply that maintaining SII within an optimal range could be crucial in reducing mortality risk.

Differential impacts of fat and muscle mass on cardiovascular and non-cardiovascular mortality in individuals with type 2 diabetes

BACKGROUND

The distribution of fat and muscle mass in different regions of the body can reflect different pathways to mortality in individuals with diabetes. Therefore, we investigated the associations between whole-body and regional body fat and muscle mass with cardiovascular disease (CVD) and non-CVD mortality in type 2 diabetes (T2D).

METHODS

Within the National Health and Nutrition Examination Survey 1999-2006, 1417 adults aged ≥50 years with T2D were selected. Dual-energy X-ray absorptiometry was used to derive whole-body, trunk, arm, and leg fat mass and muscle mass indices (FMI and MMI). Mortality data until 31 December 2019 were retrieved from the National Death Index. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated from Cox proportional hazard models.

RESULTS

A total of 1417 participants were included in this study (weighted mean age [standard error]: 63.7 [0.3] years; 50.5% female). Over a median follow-up of 13.6 years, 797 deaths were recorded (371 CVD-related and 426 non-CVD deaths). Higher FMI in the arm was associated with increased risk of non-CVD mortality (fourth quartile [Q4] vs. first quartile [Q1]: HR 1.82 [95% CI 1.13-2.94]), whereas higher FMI in the trunk or leg was not significantly associated with CVD or non-CVD mortality. Conversely, higher arm MMI was associated with a lower risk of both CVD (Q4 vs. Q1: HR 0.51 [95% CI 0.33-0.81]) and non-CVD (Q4 vs. Q1: HR 0.56 [95% CI 0.33-0.94]) mortality. There was a significant interaction between smoking status and arm FMI on non-CVD mortality (P for interaction = 0.007). Higher arm FMI was associated with a higher risk of non-CVD mortality among current or former smokers (Q4 vs. Q1: HR 2.67 [95% CI 1.46-4.88]) but not non-smokers (Q4 vs. Q1: HR 0.85 [95% CI 0.49-1.47]).

CONCLUSIONS

Fat mass and muscle mass, especially in the arm, are differently associated with CVD and non-CVD mortality in people with T2D. Our findings underscore the predictive value of body compositions in the arm in forecasting mortality among older adults with T2D.

Obesity paradox of cardiovascular mortality in older adults in the United States: A cohort study using 1997-2018 National Health Interview Survey data linked with the National Death Index

BACKGROUND

Large-scale, population-based investigations primarily investigating the association between body mass index (BMI) and cardiovascular disease (CVD) mortality among older and younger adults in the United States (U.S.) are lacking.

OBJECTIVE

To evaluate the relationship between BMI and CVD mortality in older (≥65 years) and younger (<65 years) adults and to identify the nadir for CVD mortality.

DESIGN

This cohort study used serial cross-sectional data from the 1997 to 2018 National Health Interview Survey (NHIS) linked with the National Death Index. NHIS is an annual nationally representative household interview survey of the civilian noninstitutionalized U.S.

POPULATION

SETTING

Residential units of the civilian noninstitutionalized population in the U.S.

PARTICIPANTS

The target population for the NHIS is the civilian noninstitutionalized U.S. population at the time of the interview. We included all adults who had BMI data collected at 18 years and older and with mortality data being available. To minimize the risk of reverse causality, we excluded adults whose survival time was ≤2 years of follow-up after their initial BMI was recorded and those with prevalent cancer and/or CVD at baseline.

METHODS

We used the BMI record obtained in the year of the NHIS survey. Total CVD mortality used the NHIS data linked to the latest National Death Index data from the survey inception to December 31, 2019. We performed multivariable Cox proportional hazards regression models to estimate adjusted hazard ratios (aHRs) and 95 % confidence intervals (CIs).

RESULTS

The study included 425,394 adults; the mean (SD) age was 44 (16.7) years. During a median follow-up period of 11 years, 12,089 CVD-related deaths occurred. In older adults, having overweight was associated with a lower risk of CVD mortality (aHR 0.92 [95 % CI, 0.87-0.97]); having class I obesity (1.04 [0.97-1.12]) and class II obesity (1.12 [1.00-1.26]) was not significantly associated with an increased CVD mortality; and having class III obesity was associated with an increased risk of CVD mortality (1.63 [1.35-1.98]), in comparison with adults who had a normal BMI. Yet, in younger adults, having overweight, class I, II, and III obesity was associated with a progressively higher risk of CVD mortality. The nadir for CVD mortality is 28.2 kg/m2 in older adults and 23.6 kg/m2 in younger adults.

CONCLUSION

This U.S. population-based cohort study highlights the significance of considering age as a crucial factor when providing recommendations and delivering self-care educational initiatives for weight loss to reduce CVD mortality.

Body roundness index improves the predictive value of cardiovascular disease risk in hypertensive patients with obstructive sleep apnea: a cohort study

BACKGROUND

Obesity, especially visceral obesity, plays an important role in the progression of cardiovascular disease (CVD). The body roundness index (BRI) is a new measure of obesity that is considered to reflect visceral obesity more comprehensively than other measures. This study aims to evaluate the relationship between BRI and CVD risk in hypertensive patients with obstructive sleep apnea (OSA) and explore its superiority in predicting CVD.

METHODS

The Cox proportional hazards model was used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for incident CVD. The area under the curve (AUC), continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI) were used to assess which measures of obesity had the best predictive value for CVD risk.

RESULTS

During a median follow-up period of 6.8 years, 324 participants suffered a CVD event. After multivariable adjustment, compared with the reference group (the first tertile), the HRs (95% CI) of CVD were 1.25 (95% CI, 0.93-1.70) and 1.74 (95% CI, 1.30-2.33) for subjects in the tertile 2 and tertile 3 groups, respectively. Compared with other measurement indicators, BRI has the highest predictive value for CVD risk [AUC: 0.627, 95% CI: 0.593-0.661]. The addition of the BRI to the fully adjusted multivariate model improved the predictive power for CVD, which was validated in the continuous NRI and the IDI (all P < .05).

CONCLUSIONS

BRI was significantly associated with the risk of CVD in hypertensive patients with OSA. Furthermore, BRI may improve CVD risk prediction in hypertensive patients with OSA.

Association of the controlling nutritional status score with all-cause mortality and cancer mortality risk in patients with type 2 diabetes: NHANES 1999-2018

OBJECTIVE

There are studies on the nutritional status of type 2 diabetes (T2D), but there are no large cohort studies on the prognosis of Controlling Nutritional Status (CONUT) score for T2D. The aim of this study was to examine the association between CONUT score and all-cause mortality as well as cancer mortality in adults with T2D.

METHODS

For this study, we analyzed a total of 3763 adult patients with T2D who were part of the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. Mortality outcomes were determined by linking to the National Death Index records as of December 31, 2019. Cox proportional risk models were used to estimate risk ratios (HRs) and 95% confidence intervals (CIs) for all-cause and cancer deaths.

RESULTS

During the mean follow-up of 8.17 years, there were 823 deaths from all causes and 155 deaths from cancer. After adjusting for multiple variables, the risk of all-cause mortality was higher in patients with a Mild (CONUT score ≥ 2), compared with patients with a Normal (CONUT score of 0-1). All-cause mortality risk was 39% higher, and cancer mortality risk was 45% higher. Consistent results were observed when stratified by age, sex, race, BMI, smoking status, and glycated hemoglobin levels.

CONCLUSIONS

In a nationally representative sample of American adults with T2D, we found an association between CONUT score and all-cause mortality and cancer mortality.

Body mass index versus surrogate measures of central adiposity as independent predictors of mortality in type 2 diabetes

BACKGROUND

An "obesity paradox" for mortality has been shown in chronic disorders such as diabetes, and attributed to methodological bias, including the use of body mass index (BMI) for obesity definition. This analysis investigated the independent association of BMI versus surrogate measures of central adiposity with all-cause mortality in individuals with type 2 diabetes.

METHODS

The Renal Insufficiency And Cardiovascular Events Italian Multicentre Study is a prospective cohort study that enrolled 15,773 patients in 19 Italian centres in 2006-2008. Exposures were BMI and the surrogate measures of central adiposity waist circumference (WC), waist-to-height ratio (WHtR), and A Body Shape Index (ABSI). Vital status was retrieved on 31 October 2015 for 15,656 patients (99.3%), RESULTS: Age- and sex-adjusted hazard ratios and 95% confidence intervals were significantly higher in BMI-based underweight (1.729 [1.193-2.505), P = 0.004), moderately obese (1.214 [1.058-1.392), P = 0.006) and severely obese (1.703 [1.402-2.068), P < 0.0001), lower in overweight (0.842 [0.775-0.915), P < 0.0001) and similar in mildly obese (0.950 [0.864-1.045), P = 0.292), compared to normal-weight individuals. When further adjusting for smoking, physical activity (PA), and comorbidities, risk was lower also in mildly obese versus normal-weight patients. The BMI-mortality relationship did not change after sequentially excluding ever smokers, individuals with comorbidities, and those died within two years from enrollment and when analyzing separately participants below and above the median age. Conversely, a paradox relationship was observed among inactive/moderately inactive, but not moderately/highly active patients. Mortality risk adjusted for age, gender, smoking, PA and comorbidities was significantly higher in the highest tertile of WC (1.279 [1.089-1.501], P = 0.003), WHtR (1.372 [1.165-1.615], P < 0.0001), and ABSI (1.263 [1.067-1.495], P = 0.007) versus the lowest tertile. However, risk was lower in the intermediate versus lowest tertile for WC (0.823 [0.693-0.979], P = 0.028), similar for WHtR, and higher, though not significantly, for ABSI.

CONCLUSIONS

An "overweight paradox" remained after controlling for age, smoking, and comorbidities, arguing against a collider bias or reverse causation. However, it could be partly explained by confounding from PA level, possibly through its impact on lean mass and cardiorespiratory fitness. No obesity paradox was observed with WHtR and especially ABSI, which predicted mortality risk associated with central adiposity better than WC. Trial registration ClinicalTrials.gov, NCT00715481, 15 July, 2008.

One-year prevalence and clinical characteristics in chronic dizziness: The 2019-2020 Korean National Health and Nutrition Examination Survey

INTRODUCTION

In this cross-sectional study, we investigated the 1-year prevalence and related factors in the general population with an experience of chronic dizziness.

METHODS

This study analyzed persons (n = 5,163) who respond to dizziness and nutrition questionnaire from participant of Korean National Health and Nutrition Examination Survey (KNHANES, 2019-2020).

RESULTS

Of individuals over 40 years, 25.3% of the general population (61.6% females) reported either dizziness or imbalance for the past year. Moreover, 4.8% of the patients reported they suffered from chronic dizziness or imbalance for more than 3 months. In multiple regression analysis, patients with chronic dizziness were older, females, had lower body mass index (BMI), had stress awareness, and had a history of tinnitus within 1 year (>5 min per episode). Relative to normal body weight, both overweight and mild obesity (obesity stages 1 and 2) were associated with a significantly lower risk of chronic dizziness. Overweight, obesity stage 1, and obesity stage 2 had odds ratios of 0.549 [95% confidence interval (CI), 0.332-0.910], 0.445 (95% CI, 0.273-0.727), and 0.234 (95% CI, 0.070-0.779), respectively.

CONCLUSIONS

In this study, the prevalence of chronic dizziness in the general population was 4.8%. Our study demonstrated that overweight and mild obesity were independently associated with a lower risk of chronic dizziness in adults for the past year. Therefore, the optimal BMI for patients with dizziness should be defined and managed according to an integrated care pathway.

Distribution of lean mass and mortality risk in patients with type 2 diabetes

AIMS

The aim of the study is to evaluate the association of distribution of lean mass with the risk of all-cause mortality among patients with type 2 diabetes.

METHODS

The present cohort study included 2 335 patients with type 2 diabetes. Lean mass was assessed by dual energy X-ray absorptiometry. Cox proportional hazards regressions were used to estimate the association of lean mass distribution on the risk of mortality.

RESULTS

The average age of the patients was 58 years at baseline and 51.4% of patients were women. During a median follow-up of 4.31 years, 128 patients died. The multivariable-adjusted hazards ratios for all-cause mortality were 1.00, 1.63 (0.89-2.99), and 2.68(1.51-4.76) across the tertiles of android-to-gynoid lean mass ratio (P for trend < 0.001), respectively. The positive association of android-to-gynoid lean mass ratio with the risk of all-cause mortality was present among patients of different ages, body mass index ≥ 24 kg/m², hemoglobin A1c ≥ 7.0%, nonsmokers, men, patients using insulin, and patients with diabetes durations of more than 10 years.

CONCLUSIONS

Higher android-to-gynoid lean mass ratio, assessed by dual energy X-ray absorptiometry, was significantly associated with increased risk of all-cause mortality among patients with type 2 diabetes.

Dose-response relationship between Chinese visceral adiposity index and type 2 diabetes mellitus among middle-aged and elderly Chinese

INTRODUCTION

China has the largest population of diabetic patients (about 116 million) in the world. As a novel model of the fat index for Chinese people, the Chinese visceral adiposity index (CVAI) was considered a reliable indicator to assess the dysfunction of visceral fat. This study aimed to explore the dose-response relationship between CVAI and type 2 diabetes mellitus (T2DM) in the Chinese population, considering CVAI as a continuous/categorical variable.

METHOD

Baseline and follow-up data were collected from waves 2011 and 2015, respectively, of the China Health and Retirement Longitudinal Study (CHARLS). Multivariate logistic regression models were used to explore the relationship between CVAI and T2DM. We built three models to adjust the possible effect of 10 factors (age, gender, education level, location, marital status, smoking status, drinking status, sleep time, systolic blood pressure (SBP), and diastolic blood pressure (DBP)) on the outcome. The restricted cubic splines were used to examine possible non-linear associations and visualize the dose-response relationship between CVAI and T2DM.

RESULTS

A total of 5,014 participants were included, with 602 (12.00%) T2DM patients. The last CVAI quartile group (Q4) presented the highest risk of T2DM (OR, 2.17, 95% CI, 1.67-2.83), after adjusting for all covariates. There was a non-linear (U-shaped) relationship between the CVAI and the risk of T2DM (p for non-linear <0.001) in the restricted cubic spline regression model. CVAI was a risk factor of T2DM when it exceeded 92.49; every interquartile range (IQR) increment in the CVAI was associated with a 57% higher risk of developing T2DM (OR = 1.57, 95% CI = 1.36-1.83) after adjusting for potential confounders. The area under the receiver operating characteristic curve (AUC) (95% confidence interval) for CVAI was 0.623, and the optimal cutoff point was 111.2. There was a significant interaction between CVAI and gender by stratified analysis.

CONCLUSION

CVAI was closely associated with the risk of T2DM and might possibly be a potential marker in predicting T2DM development. The outcome suggested that it might be better to maintain CVAI within an appropriate range.

The obesity paradox and orthopedic surgery

The Obesity Paradox describes the counterintuitive finding that although obesity contributes to the development of chronic conditions such as chronic kidney disease and cardiovascular disease, obesity seems to improve mortality in patients with these diseases. This paradox has also been sited in the critical care literature in regard to acute kidney injury, obesity and mortality. This study's objective is to examine the impact of obesity and post-surgical acute kidney injury on hospital length of stay and 2-year mortality after orthopedic surgery.We reviewed the electronic medical records of all adult elective orthopedic surgery patients over 2 years in a large academic hospital. The 1783 patients who met inclusion criteria were divided into obese (body mass index, BMI ≥ 30, n = 1123) and non-obese groups (BMI <30, n = 660). Demographics, medications, comorbidities, and perioperative variables were included in multivariable logistic regression analyses with acute kidney injury, length of hospital stay, and two-year mortality as primary outcomes. Outcomes were analyzed for the entire group, the obese cohort and the non-obese cohort.Acute kidney injury developed in 5% of the post-surgical orthopedic patients. Obesity increased the likelihood of developing acute kidney injury post orthopedic surgery (odds ratio [OR] = 1.82; 95% Confidence interval [CI] 1.05-3.15, P = .034). Acute kidney injury increased length of stay by 1.3 days and increased the odds of two-year mortality (OR = 2.08; 95% CI 1.03-4.22, P = .041). However, obese patients had a decreased likelihood of two-year mortality (OR = 0.53; 95% CI 0.33-0.84, P = .009).In adult orthopedic surgery patients, obesity increased the risk of acute kidney injury. Patients who developed an acute kidney injury had longer hospital stays and higher two-year mortality. Paradoxically, obesity decreased two-year mortality.

Shape of BMI-Mortality Risk Associations: Reverse Causality and Heterogeneity in a Representative Cohort of US Adults

OBJECTIVE

This study examines BMI-mortality associations and evaluates strategies intended to limit reverse causality. Heterogeneity in BMI-mortality risk associations across subgroups and causes of death is explored.

METHODS

A cohort of 654,382 adults from the US National Health Interview Survey was constructed. Associations between unit BMI levels and mortality were estimated using Cox proportional hazards models, including and excluding the first 5 years of follow-up, with and without controls for smoking or preexisting conditions, and including and excluding ever-smokers and individuals with preexisting conditions. Stratified analyses by individual characteristics were performed.

RESULTS

Addressing reverse causality led to reduced risk of mortality among those with low BMI levels (<18 kg/m² ). Excluding ever-smokers and individuals with preexisting conditions further led to increased risk among those with high BMI levels (between 33 kg/m² and >40 kg/m² ) and lowered the estimated nadir risk from 27 kg/m² to 23 kg/m² . After excluding ever-smokers and individuals with preexisting conditions, limiting the analysis to >5 years of follow-up produced no substantive changes. Heterogeneous results were observed across individual characteristics, particularly age and causes of death.

CONCLUSIONS

The exclusion of smokers and individuals with preexisting conditions alters the BMI-mortality risk association and results in a somewhat lower range of BMI with minimum mortality risk.

Association between body mass index and mortality in atrial fibrillation patients with and without diabetes mellitus: Insights from a multicenter registry study in China

BACKGROUND AND AIMS

The aim of this study was to evaluate the association between body mass index (BMI) and mortality in atrial fibrillation (AF) patients with and without diabetes mellitus (DM).

METHODS AND RESULTS

A total of 1991 AF patients were enrolled and divided into two groups according to whether they have DM at recruitment. Baseline information was collected and a mean follow-up of 1 year was carried out. The primary outcome was defined as all-cause mortality with the secondary outcomes including cardiovascular mortality, stroke and major adverse events (MAEs). Univariable and multivariable Cox regression were performed to estimate the association between BMI and 1-year outcomes in AF patients with and without DM. 309 patients with AF (15.5%) had comorbid DM at baseline. Patients with DM were more likely to have cardiovascular comorbidities, receive relevant medications but carry worse 1-year outcomes. Multivariable Cox regressions indicated that elevated BMI was related with reduced risk of all-cause mortality, cardiovascular mortality and major adverse events. Compared to normal weight, overweight [HR (95% CI): 0.548 (0.405-0.741), p < 0.001] and obesity [HR (95% CI): 0.541 (0.326-0.898), p = 0.018] were significantly related with decreased all-cause mortality for the entire cohort. Remarkably reduced all-cause mortality in the overweight [HR (95% CI): 0.497 (0.347-0.711), p < 0.001] and obesity groups [HR (95% CI): 0.405 (0.205-0.800), p = 0.009] could also be detected in AF patients without DM, but not in those with DM.

CONCLUSION

Elevated BMI was associated with reduced mortality in patients with AF. This association was modified by DM. The obesity paradox confined to AF patients without DM, but could not be generalized to those with DM.

Systematic examination of a heart failure risk prediction tool: The pooled cohort equations to prevent heart failure

Identification of individuals at risk for heart failure is needed to deliver targeted preventive strategies and maximize net benefit of interventions. To examine the clinical utility of the recently published heart failure-specific risk prediction model, the Pooled Cohort Equations to Prevent Heart Failure, we sought to demonstrate the range of risk values associated with diverse risk factor combinations in White and Black men and women. We varied individual risk factors while holding the other risk factors constant at age-adjusted national mean values for risk factors in each race-sex and age group. We also examined multiple combinations of risk factor levels and examined the range of predicted 10-year heart failure risk using the Pooled Cohort Equations to Prevent Heart Failure risk tool. Ten-year predicted heart failure risk varied widely for each race-sex group across a range of ages and risk factor scenarios. For example, predicted 10-year heart failure risk in a hypothetical 40 year old varied from 0.1% to 9.7% in a White man, 0.5% to 12.3% in a Black man, <0.1% to 9.3% in a White woman, and 0.2% to 28.0% in a Black woman. Higher risk factor burden (e.g. diabetes and hypertension requiring treatment) consistently drove higher risk estimates in all race-sex groups and across all ages. Our analysis highlights the importance of a race and sex-specific multivariable risk prediction model for heart failure to personalize the clinician-patient discussion, inform future practice guidelines, and provide a framework for future risk-based prevention trials for heart failure.

Association between diet quality and obesity indicators among the working-age adults in Inner Mongolia, Northern China: a cross-sectional study

Background

Obesity is a major risk factor for the global burden of disease in countries that are economically developed or not. This study aimed to investigate the association between diet quality and obesity indicators applying DASH and aMed.

Methods

This cross-sectional study on adult nutrition and chronic disease in Inner Mongolia (n = 1320). Dietary data were collected using 24-h diet recall for 3 consecutive days and weighing method. DASH and aMed were used to assess the dietary quality. WC, BMI and WC-BMI were used as obesity indicators. Logistic regression models were used to examine the associations between diet quality and obesity indicators.

Results

Higher diet quality, assessed by DASH, was only associated with WC. The odds ratio (OR) for abdominal obesity in the highest tertile of DASH scores compared with the lowest was 0.71 (95% confidence interval (CI) 0.53, 0.96; P_trend = 0.03). Furthermore, aMed was inversely associated with obesity indicators. OR for abdominal obesity in the highest tertile of aMed score compared with the lowest were 0.63 (95% CI 0.47, 0.87; P_trend = 0.005) and 0.57 (95% CI 0.41, 0.77; P_trend = 0.02) for overweight and obesity, respectively, and 0.60 (95% CI 0.44, 0.81; P_trend = 0.02) for high obesity risk.

Conclusions

Our findings suggest that dietary quality assessed using aMed is more closely associated with obesity than assessment using DASH in working-age adults in Inner Mongolia. The Mediterranean diet can be recommended as a healthy diet to control weight.

Is the Obesity Paradox in Type 2 Diabetes Due to Artefacts of Biases? An Analysis of Pooled Cohort Data from the Heinz Nixdorf Recall Study and the Study of Health in Pomerania

AIMS/HYPOTHESIS

There is controversy on whether an obesity paradox exists in type 2 diabetes, ie, that mortality is lowest in overweight or obesity. We examined the role of potential biases in the obesity paradox.

METHODS

From two regional population-based German cohort studies - the Heinz Nixdorf Recall Study and the Study of Health in Pomerania (baseline examinations 2000-2003/1997-2001) - 1187 persons with diabetes at baseline were included (mean age 62.6 years, 60.9% males). Diabetes was ascertained by self-report of physician's diagnosis, antidiabetic medication, fasting/random glucose or haemoglobin A1c. Mortality data were assessed for up to 17.7 years. We used restricted cubic splines and Cox regression models to assess associations between body mass index (BMI) and mortality. Sensitivity analyses addressed, inter alia, exclusion of early death cases, of persons with cancer, kidney disease or with history of cardiovascular diseases, and of ever smokers. Furthermore, we examined the role of treatment bias and collider bias for the obesity paradox.

RESULTS

In spline models, mortality risk was lowest for BMI at about 31 kg/m2. Sensitivity analyses carried out one after another had hardly any impact on this result. In our cohort, persons with diabetes and BMI ≥30 kg/m2 did not have better treatment than non-obese patients, and we found that collider bias played only a minor role in the obesity paradox.

CONCLUSION

In a cohort of 1187 persons with diabetes, mortality risk was lowest in persons with moderate obesity. We cannot explain this result by a variety of sensitivity analyses.

Association of obesity with cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease: Insights from TECOS

BACKGROUND

Obesity is a risk factor for type 2 diabetes (T2D) and cardiovascular disease (CVD). Whether obesity affects outcomes among those with T2D and atherosclerotic CVD (ASCVD) remains uncertain. Our objective was to investigate the relationship between body mass index (BMI) and ASCVD outcomes among TECOS participants with T2D and ASCVD.

METHODS

BMI categories were defined as underweight/normal weight (BMI <25 kg/m²), overweight (25-29.9 kg/m²), obese class I (30-34.9 kg/m²), obese class II (35-39.9 kg/m²), and obese class III (≥ 40 kg/m²). Asian-specific BMI categories were applied to Asian participants. Kaplan-Meier survival analysis and Cox proportional hazards models were used to examine associations between baseline BMI and a composite CV outcome (CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina).

RESULTS

For 14,534 TECOS patients with available BMI, mean age was 65.5 years; 29.3% were female, 32.0% non-White, and 23.1% insulin-treated, with median 3 years' follow-up. At baseline, 11.6% (n = 1686) were underweight/normal weight, 38.1% (n = 5532) overweight, 32.2% (n = 4683) obese class I, 12.4% (n = 1806) obese class II, and 5.7% (n = 827) obese class III. The composite CV outcome occurred in 11.4% (n = 1663) of participants; the outcome risk was lower, compared with under/normal weight, in overweight (HR 0.83, 95% CI 0.71-0.98) and obese class I (HR 0.79, 95% CI 0.67-0.93) individuals. Obesity was not associated with worse glycemic control.

CONCLUSIONS

The majority of TECOS participants with ASCVD and T2D were overweight or obese, yet overweight or obese class I individuals had lower CV risk than those who were under/normal weight. These results suggest the presence of an obesity paradox, but this paradox may reflect an epidemiological artifact rather than a true negative association between normal weight and clinical outcomes.

Contrasting Associations of Body Mass Index and Hemoglobin A1c on the Excess Risk of Acute Myocardial Infarction and Heart Failure in Type 2 Diabetes Mellitus

Background Body mass index (BMI) may be a stronger risk factor for heart failure than for coronary heart disease in type 2 diabetes mellitus, but prior studies have not been powered to investigate the relative and absolute risks for acute myocardial infarction and heart failure in type 2 diabetes mellitus by BMI and glycemic level combined as compared with age- and sex-matched general population comparators. Methods and Results We identified 181 045 patients from The Swedish National Diabetes Registry, registered during 1998 to 2012 and 1538 434 general population comparators without diabetes mellitus, matched for age, sex, and county, all without prior major cardiovascular disease. Cases and comparators were followed with respect to the outcomes through linkage to the Swedish Inpatient Registry. Over a median follow-up time of 5.7 years, there were 28 855 acute myocardial infarction and 33 060 heart failure cases among patients and comparators. Excess risk (above that of comparators in whom no data on hemoglobin A1c and BMI was available), incidence rates and hazard ratios for heart failure were substantially higher among the obese patients compared with those with low BMI, where very obese patients (BMI ≥40 kg/m2) who also had poor glycemic control, suffered a 7-fold risk of heart failure versus comparators (reference level). By contrast, for acute myocardial infarction, the highest absolute and relative risks were found among patients with poor glycemic control, with no additional risk conferred by increasing BMI. Conclusions BMI is a strong independent risk factor for heart failure but not for acute myocardial infarction among patients with type 2 diabetes mellitus.

Synergic Impact of Body Mass Index, Diabetes, and Age on Long-Term Mortality in Japanese Incident Hemodialysis Patients: A Cohort Study on a Large National Dialysis Registry

OBJECTIVES

The relationships among body mass index (BMI), diabetes, age, and all-cause mortality in hemodialysis patients remain unclear. We examined BMI-stratified relationships between diabetes, age, and the risk of long-term mortality in incident hemodialysis patients.

METHODS

This is a cohort study. Data were obtained from the national dialysis registry in Japan 2007 that included 35,415 incident hemodialysis patients and 6,061 patients aged ≥20 years with BMI data. Patients were divided into 6 categories according to baseline BMI (low: <18.5, normal: 18.5-25, Obesity: ≥25) and the presence or absence of diabetes. The primary outcome was all-cause mortality during a 5-year follow-up. Hazard ratios were estimated using Cox's model for the relationships among diabetes, BMI categories, and all-cause mortality, and adjusted for potential confounders. Patients with a normal BMI and non-diabetic were the reference category. We also examined the effects of age on these relationships.

RESULTS

A total of 6,061 patients, including 3,239 with diabetes, were enrolled. During the follow-up, 31.0% and 30.7% of all and diabetic patients, respectively, died. Cox's regression analysis showed that low BMI, but not obesity, was independently associated with an increased risk of all-cause death in patients with and without diabetes. When patients were divided into 2 groups-younger and older than 60 years-the risk of mortality in both groups was increased in low BMI with diabetes.

CONCLUSIONS

Among Japanese incident hemodialysis patients, low BMI increases the risk of all-cause mortality. The markedly high mortality rate in diabetic patients with low BMI regardless of age warrants attention.

Genomics of Early Cardiac Dysfunction and Mortality in Obese Drosophila melanogaster

In experimental evolution, we impose functional demands on laboratory populations of model organisms using selection. After enough generations of such selection, the resulting populations constitute excellent material for physiological research. An intense selection regime for increased starvation resistance was imposed on 10 large outbred Drosophila populations. We observed the selection responses of starvation and desiccation resistance, metabolic reserves, and heart robustness via electrical pacing. Furthermore, we sequenced the pooled genomes of these populations. As expected, significant increases in starvation resistance and lipid content were found in our 10 intensely selected SCO populations. The selection regime also improved desiccation resistance, water content, and glycogen content among these populations. Additionally, the average rate of cardiac arrests in our 10 obese SCO populations was double the rate of the 10 ancestral CO populations. Age-specific mortality rates were increased at early adult ages by selection. Genomic analysis revealed a large number of single nucleotide polymorphisms across the genome that changed in frequency as a result of selection. These genomic results were similar to those obtained in our laboratory from less direct selection procedures. The combination of extensive genomic and phenotypic differentiation between these 10 populations and their ancestors makes them a powerful system for the analysis of the physiological underpinnings of starvation resistance.

A Multicenter Large-Scale Retrospective Analysis of the Correlation between Body Mass Index and All-Cause Mortality in Patients with Type 2 diabetes Mellitus: A Seven-Year Real-World Study

Aims: To investigate the association between body mass index (BMI) and all-cause mortality in patients with type 2 diabetes mellitus (T2DM) and to determine any sex-specific differences in this association. Methods: We retrospectively enrolled patients with T2DM and investigated the annual death data for seven years starting from 2010. All-cause mortality was calculated using Life Tables analysis. Multivariate Cox proportional hazards analysis was performed to identify the association between BMI and mortality. Results: During a mean survey period of 7.33 ± 1.42 years (X± SD), 996 of the 17259 patients enrolled died, resulting in an all-cause mortality rate of 5.77%, with no significant difference between women and men (6.04% vs. 5.56%; x² = 1.766, P = 0.184). The top three causes of death were ischemic heart disease, cerebrovascular disease, and chronic kidney failure. A total of 87, 266, 332, and 311 patients with a BMI of <18.5, 18.5-23.99, 24.0-27.99, and ≥28.0 kg/m², respectively, died, with the corresponding mortality rate calculated at 15.45%, 3.30%, 5.80%, and 10.70%, respectively. The BMI value associated with the highest all-cause mortality was <18.5 kg/m², but this association was only significant in women aged <50 years (HR: 3.12; 95% CI, 1.62-4.34; P < 0.001). Conclusions: In patients with T2DM, a low BMI in women aged <50 years predicted high all-cause mortality.

Flawed methods and inappropriate conclusions for health policy on overweight and obesity: the Global BMI Mortality Collaboration meta-analysis

Guideline recommendations and health policy decisions rely on evidence from clinical and epidemiological studies. Adequate methodology and appropriate conclusions are essential to support healthcare and health policy decisions. An analysis of body mass index and mortality by the Global BMI Mortality Collaboration (GBMC) concluded that the association of excess body weight with higher mortality was similar worldwide and that overweight and obesity should be combated everywhere. To reach this conclusion, the GBMC used highly selected data, rather than a systematic approach. The GBMC initially chose individual participant data from 239 prospective studies with approximately 10.6 million participants. The GBMC then excluded over 60% of data and over 75% of fatal events by eliminating all cases with any reported disease at baseline or smoking history and all events within the first 5 years of follow-up. After applying these restrictions, the association of overweight with lower mortality was reversed and the association of obesity with higher mortality was increased. Given the major flaws in the selection process, in the adequacy of the data, in the data analysis, and in the interpretation, the GBMC conclusions should be viewed sceptically as a guide to action, either for clinical decisions or for public health in general. The flawed conclusion that overweight is uniformly associated with substantially increased risk of death and thus should be combated in any circumstances may lead not only to unjustified treatment efforts and potential harm in a wide range of clinical conditions but also to a tremendous waste of resources.

Body mass index and the risk of mortality among Chinese adults with Type 2 diabetes

AIMS

To examine the associations between BMI and the risks of all-cause, cardiovascular disease (CVD)-specific and cancer-specific mortality among people with Type 2 diabetes, and thus provide recommendations for weight management in the population.

METHODS

This retrospective cohort study was conducted among 52 763 people with newly diagnosed Type 2 diabetes between 1 January 2004 and 31 December 2014 in Shanghai, China. All cases of death were identified by linking to the Shanghai Vital Statistics. Some 52 488 people were included in the analysis. Survival curves for people with different BMI categories were plotted using the Kaplan-Meier method. Cox proportional hazard models within or without restricted cubic spline functions were applied to examine the potential non-linear or linear relationship between BMI and the risk of mortalities respectively.

RESULTS

A total of 4777 deaths were identified during an average of 6-year follow-up. An L-shaped association was observed between BMI and all-cause mortality in men (P for overall association < 0.001 and P for non-linearity < 0.001) while a U-shaped association was found in women (P for overall association < 0.001 and P for non-linearity< 0.001). In men, no significant association was observed for BMI with cancer-specific and CVD-specific mortality. In women, an increased risk of cancer-specific mortality was observed with increasing BMI, whereas decreasing BMI was associated with the increased CVD-specific mortality rate.

CONCLUSION

The increased all-cause mortality in men with low BMI and in women with either low or high BMI indicate the importance of keeping BMI in a normal range for Chinese adults with Type 2 diabetes.

Body mass index and risk of all-cause mortality with normoglycemia, impaired fasting glucose and prevalent diabetes: results from the Rural Chinese Cohort Study

BACKGROUND

Previous evidence of an association between body mass index (BMI) and mortality in patients with diabetes was inconsistent. The BMI-mortality association with normal fasting glucose (NFG), impaired fasting glucose (IFG) and prevalent diabetes is still unclear in the Chinese population.

METHODS

We analysed data for 17 252 adults from the Rural Chinese Cohort Study during 2007-2008 and followed for mortality during 2013-2014. Participants were classified with NFG, IFG and diabetes according to baseline measurement values of fasting glucose and self-reported diabetes. Multivariable Cox proportional hazard models were used to calculate HRs and 95% CIs across BMI categories by glycemic status.

RESULTS

During the 6-year follow-up, 1109 participants died (563/10 181 with NFG, 349/5572 with IFG and 197/1499 with diabetes). The BMI-mortality association was curvilinear, with low BMI (even in normal range) associated with increased mortality regardless of glycemic status. In adjusted Cox models, risk of mortality showed a decreasing trend with BMI≤18 kg/m², 18<BMI≤20 kg/m² and 20<BMI≤22 kg/m² vs 22<BMI≤24 kg/m²: HR 2.83 (95% CI 1.78 to 4.51), 2.05 (1.46 to 2.87) and 1.45 (1.10 to 1.90), respectively, for NFG; 2.53 (1.25 to 5.14), 1.36 (0.86 to 2.14) and 1.09 (0.76 to 1.57), respectively, for IFG; and 4.03 (1.42 to 11.50), 2.00 (1.05 to 3.80) and 1.52 (0.88 to 2.60), respectively, for diabetes. The risk of mortality was lower for patients with diabetes who were overweight or obese versus normal weight.

CONCLUSIONS

Low BMI was associated with increased mortality regardless of glycemic status. Future studies are needed to explain the 'obesity paradox' in patients with diabetes.

Body mass index and the all-cause mortality rate in patients with type 2 diabetes mellitus

AIMS

The relationship between obesity and mortality rate among diabetic patients is a controversial topic. The aim of this study was to investigate the association between obesity and all-cause mortality risk in patients with type 2 diabetes.

METHODS

In this retrospective database study, 2383 patients with type 2 diabetes, who had been registered in the Isfahan Endocrine and Metabolism Research Center, Iran, were enrolled between 1992 and 2010. The mean (SD) of diabetes duration and follow-up period was 15.5 (8.0) and 7.8 (3.9) years. The main outcome was all-cause mortality. All-cause mortality rates were calculated for the body mass index (BMI) categories of underweight, normal, overweight and class I, II and III obese. Cox proportional hazard models were used to estimate the adjusted hazard ratio for BMI as categorical variable using BMI of 18.5-24.9 kg/m² as the reference group.

RESULTS

The mortality rate in patients with normal weight was higher than overweight patients (59.11 vs. 33.17 per 1000 person-years). The adjusted hazard ratios of all-cause mortality were 0.82 [95%CI 0.68-0.99; P = 0.037], 0.79 [95%CI 0.61-1.02; P = 0.069], 0.71 [95%CI 0.42-1.19; P = 0.191] and 1.36 [95%CI 0.55-3.33; P = 0.507] for overweight, class I, II and III obesity, respectively. When BMI was included in the Cox model as a time-dependent variable, the U-shaped relationship between BMI and all-cause mortality did not change.

CONCLUSIONS

The results show a U-shaped association of BMI with all-cause mortality in patients with type 2 diabetes with the lowest risk observed among the overweight patients.

The Evidence for an Obesity Paradox in Type 2 Diabetes Mellitus

Although overweight/obesity is a major risk factor for the development of type 2 diabetes mellitus, there is increasing evidence that overweight or obese patients with type 2 diabetes mellitus experience lower mortality compared with patients of normal weight. This paradoxical finding, known as the "obesity paradox," occurs in other chronic diseases, and in type 2 diabetes mellitus is particularly perplexing given that lifestyle intervention with one goal being weight reduction is an important feature of the management of this condition. We summarize in this review the findings from clinical and epidemiologic studies that have investigated the association between overweight and obesity (usually assessed using body mass index [BMI]) and mortality in type 2 diabetes mellitus and discuss potential causes of the obesity paradox. We conclude that most studies show evidence of an obesity paradox, but important conflicting findings still exist. We also evaluate if potential bias might explain the obesity paradox in diabetes, including, for example, the presence of confounding factors, measurement error due to use of BMI as an index of obesity, and reverse causation.

Body mass index and mortality in patients with and without diabetes mellitus

OBJECTIVE

Investigate the association between body mass index (BMI), length of stay (LOS), and mortality in hospitalized patients with and without diabetes mellitus (DM).

METHODS

Historical prospectively collected data of adult patients hospitalized between 2011 and 2013. Body mass index was calculated according to measurement or self-report on admission and classified as follows: underweight (<18.5), normal weight (18.5-24.9), overweight (25-29.9), obese (30-34.9), and severely obese (≥35). The main outcomes were LOS, in-hospital, and end-of-follow-up mortality.

RESULTS

Cohort included 24 233 patients (53% male; mean age ± SD, 65 ± 18), including 7397 patients with DM (31%). Among patients with normal BMI, LOS was shorter compared with underweight patients, but it was longer compared with overweight and obese patients. Following multivariate adjustment, this difference remained significant only for patients with DM. There was a significant interaction between DM status and BMI group, in the models for in-hospital and end-of-follow-up mortality. Compared with normal BMI, in-hospital mortality risk was increased by 80% and 100% for the underweight with and without DM, respectively. For patients with and without DM, in-hospital mortality risk was 30% to 40% lower among overweight and obese patients, and there was no difference between severely obese and normal weight patients. At the end-of-follow-up, mortality risk was 1.6-fold and 1.7-fold higher among underweight patients with and without DM, respectively. For overweight, obese, and severely obese patients, mortality risk was decreased by 30% to 40% in those with DM and by 20% to 30% in those without DM.

CONCLUSIONS

In hospitalized patients with and without DM, there was an inverse association between BMI and mortality.

Predictors of hypoglycemia in hospitalized patients with diabetes mellitus

Hypoglycemia is common among hospitalized patients with diabetes mellitus (DM), and is associated with increased morbidity and mortality. Identify pre-admission risk factors associated with in-hospital hypoglycemia. Historical prospectively collected data of adult DM patients hospitalized to medical wards between 2011 and 2013. Hypoglycemia and serious hypoglycemia were defined as at least one blood glucose measurement ≤ 70 and < 54 mg/dl, respectively, during hospitalization. The primary outcome was in-hospital hypoglycemia. The cohort included 5301 patients (mean age 73 ± 13 years, 51% male), including 792 patients (15%) with hypoglycemia, among them 392 patients (7%) with serious hypoglycemia. Patients with hypoglycemia or serious hypoglycemia during hospitalization were older, compared to patients without hypoglycemia and more likely to have chronic renal failure and cerebrovascular disease. Malignancy and female gender were risk factors for hypoglycemia, but not for serious hypoglycemia, while congestive heart failure was associated with increased risk only for serious hypoglycemia. Diabetes mellitus' duration over 10 years was associated with an almost threefold increased risk for hypoglycemia, compared to DM duration less than a year. Insulin treatment and glycated hemoglobin > 9% were also more common in patients with hypoglycemia. Insulin treatment was associated with a fourfold increase in the risk for hypoglycemia among all glycated hemoglobin categories. Our results identified several risk factors for in-hospital hypoglycemia in patients with DM. These findings may lead to appropriate monitoring and early intervention to prevent hypoglycemia and to reduce morbidity and mortality associated with in-hospital hypoglycemia.

Association of Body Mass Index with Risk of Major Adverse Cardiovascular Events and Mortality in People with Diabetes

Background

The relationship between cardiovascular and all-cause mortality and obesity in people with diabetes is still controversial. We investigated the association of body mass index (BMI) with the risk of major adverse cardiovascular events (MACE) and all-cause mortality in people with diabetes.

Methods

In total, 48,438 people with diabetes were enrolled in the Korean National Health Insurance Service-National Health Screening Cohort from 2002 to 2003 and were followed until 2013. Baseline BMI was categorized as underweight (<18.5 kg/m²), normal-weight (18.5–22.9 kg/m²), overweight (23.0–24.9 kg/m²), obese class I (25.0–29.9 kg/m²), and obese class II (≥30.0 kg/m²).

Results

During a median of 10.7 years of follow-up (interquartile range, 10.2–11.2 years), there were 7,360 MACE and 5,766 deaths. Compared to those in the normal-weight group, the fully adjusted hazard ratios (HRs) for MACE were 1.09 (95% confidence interval [CI], 0.92–1.29), 0.91 (95% CI, 0.85–0.97), 0.93 (95% CI, 0.88–0.98), and 0.95 (95% CI, 0.84–1.06) for underweight, overweight, obese class I, and obese class II groups, respectively. The HRs for all-cause mortality were 1.75 (95% CI, 1.54–1.99), 0.74 (95% CI, 0.69–0.79), 0.67 (95% CI, 0.63–0.71), and 0.73 (95% CI, 0.63–0.85) for underweight, overweight, obese class I, and obese class II groups, respectively.

Conclusion

In people with diabetes, underweight people had a higher risk for all-cause mortality, whereas overweight or obese people had a lower risk for MACE and all-cause mortality than those with a normal weight.

BMI and Mortality in Patients With New-Onset Type 2 Diabetes: A Comparison With Age- and Sex-Matched Control Subjects From the General Population

OBJECTIVE

Type 2 diabetes is strongly associated with obesity, but the mortality risk related to elevated body weight in people with type 2 diabetes compared with people without diabetes has not been established.

RESEARCH DESIGN AND METHODS

We prospectively assessed short- and long-term mortality in people with type 2 diabetes with a recorded diabetes duration ≤5 years identified from the Swedish National Diabetes Register (NDR) between 1998 and 2012 and five age- and sex-matched control subjects per study participant from the general population.

RESULTS

Over a median follow-up of 5.5 years, there were 17,546 deaths among 149,345 patients with type 2 diabetes (mean age 59.6 years [40% women]) and 68,429 deaths among 743,907 matched control subjects. Short-term all-cause mortality risk (≤5 years) displayed a U-shaped relationship with BMI, with hazard ratios (HRs) ranging from 0.81 (95% CI 0.75-0.88) among patients with diabetes and BMI 30 to <35 kg/m² to 1.37 (95% CI 1.11-1.71) with BMI ≥40 kg/m² compared with control subjects after multiple adjustments. Long-term, all weight categories showed increased mortality, with a nadir at BMI 25 to <30 kg/m² and a stepwise increase up to HR 2.00 (95% CI 1.58-2.54) among patients with BMI ≥40 kg/m², that was more pronounced in patients <65 years old.

CONCLUSIONS

Our findings suggest that the apparent paradoxical findings in other studies in this area may have been affected by reverse causality. Long-term, overweight (BMI 25 to <30 kg/m²) patients with type 2 diabetes had low excess mortality risk compared with control subjects, whereas risk in those with BMI ≥40 kg/m² was substantially increased.

Impact of obesity on mortality in patients with diabetes: Meta-analysis of 20 studies including 250,016 patients

AIMS/INTRODUCTION

The impact of body mass index on mortality among patients with diabetes remains controversial. Therefore, we carried out a meta-analysis of pertinent studies.

MATERIALS AND METHODS

We searched OVID/MEDLINE, EMBASE and Cochrane databases for all reported studies, which investigated the relationship between body mass index and mortality in patients with diabetes. Summary estimates of hazard ratios (HRs) were obtained with a random effects model. Univariate meta-regressions were carried out.

RESULTS

A total of 20 studies including 250,016 patients with diabetes were identified. The results of the present study showed a significantly reduced risk of all-cause mortality in overweight patients (HR 0.82, 95% CI: 0.74-0.91, P < 0.0001, and I2 = 91.6%) as compared with normal weight patients. The survival benefits of obesity were only observed in the elderly patients (HR 0.69, 95% CI: 0.63-0.75, P < 0.0001, and I2 = 50.4%), but not in the younger patients (HR 1.01, 95% CI: 0.84-1.20, P = 0.96, I2 = 80.1%). Furthermore, the beneficial prognostic impacts on overweight (coefficient = 0.030, P = 0.041) and obesity (coefficient = 0.032, P = 0.010) were attenuated with clinical follow-up duration.

CONCLUSIONS

The present meta-analysis showed a significantly lower risk of all-cause mortality in overweight patients with diabetes compared with normal weight patients. However, the survival benefits of obesity were only observed among the elderly patients.

Incidence of diabetes and its mortality according to body mass index in South Koreans aged 40-79 years

Purpose

The purpose of this study was to assess diabetes incidence and all-cause mortality according to baseline body mass index (BMI) and to compare relative risks of mortality associated with incident diabetes across various BMI classes in a cohort of South Korean adults.

Patients and methods

Based on data from the National Health Insurance database of Korean individuals aged 40-79 years without preexisting diabetes, we calculated BMI at the baseline health examination. We estimated the relative risk of mortality associated with incident diabetes using time-dependent Cox models and considering the time of diabetes diagnosis.

Results

We noted 29,307 incident diabetes cases and 22,940 deaths during an 8-year follow-up of the initial cohort (n=436,692) and 73,756 incident diabetes cases and 57,556 deaths during a 10-year follow-up of the replication cohort (n=850,282). Regarding all-cause mortality, time-dependent Cox models revealed statistically significant interactions between diabetes status and baseline BMI class (P=0.018 and P<0.001 in the initial and replication cohorts, respectively). In separately conducted analyses for each BMI class, diabetes-associated relative risks for BMI values of 16.0-18.4, 18.5-22.9, 23.0-24.9, 25.0-29.9, and 30.0-34.9 kg/m² were 1.50 (95% confidence interval [CI], 1.09-2.07), 1.39 (95% CI, 1.26-1.54), 1.20 (95% CI, 1.08-1.35), 1.18 (95% CI, 1.07-1.30), and 0.97 (95% CI, 0.74-1.28) in the initial cohort, and 1.44 (95% CI, 1.18-1.74), 1.33 (95% CI, 1.26-1.41), 1.24 (95% CI, 1.16-1.31), 1.11 (95% CI, 1.05-1.17), and 0.99 (95% CI, 0.85-1.16) in the replication cohort. The increasing trend of relative risk with decreasing BMI persisted mostly among subgroups stratified according to age or sex and smoking status.

Conclusion

Incident diabetes was associated with a greater increase in all-cause mortality risk in adults with lower BMI relative to those with higher BMI. This emphasizes the importance of treatment and prevention of type 2 diabetes among normal weight or underweight adults, particularly in Asia.

Associations between body mass index and mortality or cardiovascular events in a general Korean population

Background/Objectives

The relationship between body mass index (BMI) and mortality remains controversial. Furthermore, the association between BMI and cardiovascular events (CVE) is not conclusive and may differ by ethnicity. We aimed to estimate the associations between the BMI and mortality or cardiovascular disease in a general Korean population.

Subjects/Methods

This study was based on a sample cohort database released by the Korean National Health Insurance Service. We analyzed a total of 415,796 adults older than 30 years of age who had undergone a national health examination at least once from 2002 to 2012. Hazard ratios for death and cardiovascular events were calculated using Cox proportional hazards models.

Results

For both men and women, BMI and overall mortality showed a U-shaped association, with the lowest mortality rate among those with a BMI of 25–27.4 kg/m². Compared with them, subjects with a BMI ≥ 30kg/m², men with a BMI < 25 kg/m², and women with a BMI < 22.5 kg/m² showed significantly higher overall mortality. Additionally, men with a BMI < 22.5 kg/m² and women with a BMI < 20 kg/m² displayed an increased risk of cardiovascular mortality. Unlike the mortality trend, the CVD events trend showed a linearly positive association. The risk of a CVE was the lowest in men with a BMI ranging from 20 to 22.4 kg/m² and in women with a BMI < 20 kg/m².

Conclusions

The BMI showed a U-shaped association with overall mortality, where slightly obese subjects showed the lowest rate of mortality. The CVE exhibited a linear association with the BMI, where the lowest risk was observed for normal weight subjects in a general Korean population.

A meta-analysis but not a systematic review: an evaluation of the Global BMI Mortality Collaboration

Meta-analyses of individual participant data (MIPDs) offer many advantages and are considered the highest level of evidence. However, MIPDs can be seriously compromised when they are not solidly founded upon a systematic review. These data-intensive collaborative projects may be led by experts who already have deep knowledge of the literature in the field and of the results of published studies and how these results vary based on different analytical approaches. If investigators tailor the searches, eligibility criteria, and analysis plan of the MIPD, they run the risk of reaching foregone conclusions. We exemplify this potential bias in a MIPD on the association of body mass index with mortality conducted by a collaboration of outstanding and extremely knowledgeable investigators. Contrary to a previous meta-analysis of group data that used a systematic review approach, the MIPD did not seem to use a formal search: it considered 239 studies, of which the senior author was previously aware of at least 238, and it violated its own listed eligibility criteria to include those studies and exclude other studies. It also preferred an analysis plan that was also known to give a specific direction of effects in already published results of most of the included evidence. MIPDs where results of constituent studies are already largely known need safeguards to their validity. These may include careful systematic searches, adherence to the Preferred Reporting Items for Systematic Review and Meta-Analyses of individual participant data guidelines, and exploration of the robustness of results with different analyses. They should also avoid selective emphasis on foregone conclusions based on previously known results with specific analytical choices.

BMI and All-Cause Mortality in Normoglycemia, Impaired Fasting Glucose, Newly Diagnosed Diabetes, and Prevalent Diabetes: A Cohort Study

OBJECTIVE

This study examined associations between BMI and mortality in individuals with normoglycemia, impaired fasting glucose (IFG), newly diagnosed diabetes, and prevalent diabetes and identified BMI ranges associated with the lowest mortality in each group.

RESEARCH DESIGN AND METHODS

A total of 12,815,006 adults were prospectively monitored until 2013. Diabetes status was defined as follows: normoglycemia (fasting glucose <100 mg/dL), IFG (100-125 mg/dL), newly diagnosed diabetes (≥126 mg/dL), and prevalent diabetes (self-reported). BMI (kg/m²) was measured. Cox proportional hazards model hazard ratios were calculated after adjusting for confounders.

RESULTS

During a mean follow-up period of 10.5 years, 454,546 men and 239,877 women died. U-shaped associations were observed regardless of diabetes status, sex, age, and smoking history. Optimal BMI (kg/m²) for the lowest mortality by group was 23.5-27.9 (normoglycemia), 25-27.9 (IFG), 25-29.4 (newly diagnosed diabetes), and 26.5-29.4 (prevalent diabetes). Higher optimal BMI by worsening diabetes status was more prominent in younger ages, especially in women. The relationship between worsening diabetes status and higher mortality was stronger with lower BMI, especially at younger ages. Given the same BMI, people with prevalent diabetes had higher mortality compared with those with newly diagnosed diabetes, and this was more striking in women than men.

CONCLUSIONS

U-curve relationships existed regardless of diabetes status. Optimal BMI for lowest mortality became gradually higher with worsening diabetes for each sex and each age-group.

Anthropometric discriminators of type 2 diabetes among White and Black American adults

BACKGROUND

The aim of the present study was to determine the best anthropometric discriminators of type 2 diabetes mellitus (T2DM) among White and Black males and females in a large US sample.

METHODS

We used Atherosclerosis Risk in Communities study baseline data (1987-89) from 15 242 participants (1827 with T2DM) aged 45-65 years. Anthropometric measures included a body shape index (ABSI), body adiposity index (BAI), body mass index, waist circumference (WC), waist:  height ratio (WHtR), and waist:  hip ratio (WHR). All anthropometric measures were standardized to Z-scores. Using logistic regression, odds ratios for T2DM were adjusted for age, physical activity, and family history of T2DM. The Akaike information criterion and receiver operating characteristic C-statistic were used to select the best-fit models.

RESULTS

Body mass index, WC, WHtR, and WHR were comparable discriminators of T2DM among White and Black males, and were superior to ABSI and BAI in predicting T2DM (P < 0.0001). Waist circumference, WHtR, and WHR were the best discriminators among White females, whereas WHR was the best discriminator among Black females. The ABSI was the poorest discriminator of T2DM for all race-gender groups except Black females. Anthropometric values distinguishing T2DM cases from non-cases were lower for Black than White adults.

CONCLUSIONS

Anthropometric measures that included WC, either alone or relative to height (WHtR) or hip circumference (WHR), were the strongest discriminators of T2DM across race-gender groups. Body mass index was a comparable discriminator to WC, WHtR, and WHR among males, but not females.

Abdominal obesity and healthcare costs related to hypertension and diabetes in older adults

ABSTRACT Objective: To analyze the association between excess abdominal fat and healthcare costs related to hypertension and diabetes Mellitus in older adults. Methods: These cross-sectional analyses are part of the Health, Wellbeing and Aging Study conducted in São Paulo, Brazil, with 806 older adults with self-reported hypertension and diabetes Mellitus. The study included the annual costs with medicines, hospital admissions, and outpatient services for hypertension and diabetes Mellitus control. Excess abdominal fat was diagnosed based on waist circumference. Level of physical activity, age, and gender were considered covariates. The sample was divided into two groups according to waist circumference. Multiple logistic regression analyzed the associations between annual costs and waist circumference. Results: The cost of services and hospitalizations (R$551.05; 95%CI=418.27-683.83) and total costs (R$817.77; 95%CI=669.21-966.33) were higher in the excess abdominal fat group. Older adults with high waist circumference had higher odds of increasing annual costs due to medicines (OR=2.6; 95%CI=1.13-3.77), regardless of gender, age, and level of physical activity. Conclusion: Healthcare costs for treating hypertension and diabetes Mellitus in older adults are higher in the presence of excess abdominal fat.

Body mass index and mortality in patients with type 2 diabetes mellitus: A prospective cohort study of 11,449 participants

AIMS

To investigate the association between body-mass index and mortality in Chinese adults T2DM.

METHODS

11,449 participants of Kailuan Study with T2DM were included in this prospective cohort study. All-cause mortality was calculated using Kaplan-Meier analysis. Cox proportional hazards analysis was used to estimate the association between BMI and mortality.

RESULTS

During a mean follow-up period of 7.25±1.42years, 1254 deaths occurred. The number of deaths of the underweight, normal weight, overweight, and obese group was 23, 389, 557, and 285; the corresponding mortality was 25.0%, 13.4%, 10.3%, and 9.4%, respectively. The obese group had the lowest all-cause mortality rate (log-rank chi-square=48.430, P<0.001). After adjusting for age, sex, fasting blood glucose, smoking status, systolic blood pressure, history of hypertension, stroke, cancer and myocardial infarction, compared with the normal weight group, Multivariate Cox proportional hazard regression analysis showed that HR (95% CI) of all-cause mortality in the underweight, overweight, and obese group was 1.497 (0.962, 2.330), 0.833 (0.728, 0.952), and 0.809 (0.690, 0.949). After stratifying for age tertiles, this trend remained.

CONCLUSIONS

In T2DM patients in north China, the risk for all-cause mortality was lower in the overweight and the obese groups than those in the normal weight and the underweight groups.

Nonlinear association of BMI with all-cause and cardiovascular mortality in type 2 diabetes mellitus: a systematic review and meta-analysis of 414,587 participants in prospective studies

AIMS/HYPOTHESIS

The relationship between BMI and mortality has been extensively investigated in the general population; however, it is less clear in people with type 2 diabetes. We aimed to assess the association of BMI with all-cause and cardiovascular mortality in individuals with type 2 diabetes mellitus.

METHODS

We searched electronic databases up to 1 March 2016 for prospective studies reporting associations for three or more BMI groups with all-cause and cardiovascular mortality in individuals with type 2 diabetes mellitus. Study-specific associations between BMI and the most-adjusted RR were estimated using restricted cubic splines and a generalised least squares method before pooling study estimates with a multivariate random-effects meta-analysis.

RESULTS

We included 21 studies including 24 cohorts, 414,587 participants, 61,889 all-cause and 4470 cardiovascular incident deaths; follow-up ranged from 2.7 to 15.9 years. There was a strong nonlinear relationship between BMI and all-cause mortality in both men and women, with the lowest estimated risk from 31-35 kg/m² and 28-31 kg/m² (p value for nonlinearity <0.001) respectively. The risk of mortality at higher BMI values increased significantly only in women, whilst lower values were associated with higher mortality in both sexes. Limited data for cardiovascular mortality were available, with a possible inverse linear association with BMI (higher risk for BMI <27 kg/m²).

CONCLUSIONS/INTERPRETATION

In type 2 diabetes, BMI is nonlinearly associated with all-cause mortality with lowest risk in the overweight group in both men and women. Further research is needed to clarify the relationship with cardiovascular mortality and assess causality and sex differences.

Body Mass Index-Related Mortality in Patients with Type 2 Diabetes and Heterogeneity in Obesity Paradox Studies: A Dose-Response Meta-Analysis

Objective

We conducted a systematic review and meta-analysis of studies to quantify the association between body mass index (BMI) and the risks of all-cause and cardiovascular mortality in patients with type 2 diabetes.

Methods

We included studies assessing the impact of BMI on all-cause and cardiovascular mortality in patients with type 2 diabetes. Data were combined using a random-effects dose-response model.

Results

Sixteen cohort studies on all-cause mortality (n = 445,125) and two studies on cardiovascular mortality (n = 92,841) were evaluated in the meta-analysis. A non-linear association was observed between BMI and all-cause mortality among patients with type 2 diabetes. With a BMI nadir of 28–30 kg/m², the risk of all-cause mortality displayed a U-shaped increase. With a BMI nadir of 29–31 kg/m², the risk of cardiovascular mortality exhibited a gradual non-linear increase for BMI > 31 kg/m². Subgroup analyses suggested that study location, diabetes duration, and smoking history may have contributed to heterogeneity among the studies.

Conclusions

An obesity paradox exists for patients with type 2 diabetes with respect to all-cause and cardiovascular mortality. Study location, diabetes duration, and smoking history might contribute to heterogeneity among obesity paradox studies of patients with type 2 diabetes.

Weight change after initiation of oral hypoglycemic monotherapy for diabetes predicts 5-year mortality: An observational study

PURPOSE

To investigate whether weight change in the first year after initiating an oral hypoglycemic agent (OHA) for type 2 diabetes treatment is associated with mortality in a national cohort.

PROCEDURES

We prospectively followed Veterans Health Administration patients with type 2 diabetes initiating treatment with an OHA and not receiving any other diabetes pharmacotherapy for at least one year. Information on OHAs, weight, co-morbidities, other medications, demographics, and laboratory measurements was obtained from electronic medical records. Logistic regression was used to estimate 5-year mortality odds by weight change during the first year after OHA treatment initiation.

FINDINGS

Patients (mean age 65years, 97% male, mean BMI 32.3kg/m2) initiating OHA monotherapy between 2003 and 2008 totaled 145,198 (metformin n=89,111, glipizide n=27,100, glyburide n=25,226, rosiglitazone n=3,761). Most patients (65%) maintained a stable weight (change ⩽5% from baseline) during the first year after OHA initiation. Those losing >5% of baseline weight had a significantly higher odds of death over the subsequent 5-years ranging from 1.64 to 2.13 depending on OHA type. In the metformin group, weight gain >5% of baseline was also associated with higher odds of 5-year mortality. The same results were obtained after conducting three sensitivity analyses that excluded patients for the following reasons: weight loss in the one year prior to OHA initiation, weight change >100lbs, or weight change >50lbs.

CONCLUSIONS

Weight loss was associated with higher odds of 5-year mortality among patients initiating an OHA, as was weight gain for metformin only.

Metabolic surgery in patients over 60 years old: short- and long-term results

PURPOSE

Laparoscopic Roux-en-Y gastric bypass can treat obesity related comorbidities and can prolong life expectancy. It remains unclear whether this type of surgery is also indicated in obese patients with advanced age.

MATERIALS AND METHODS

In this retrospective monocentric study, we investigated the morbidity and outcomes of weight and metabolic control of bariatric surgery in patients older than 60 years and compared these findings with those of younger patients.

RESULTS

At 18 months after RY gastric bypass, weight losses of respectively 30 ± 11% and 34 ± 9% of total initial body weight were measured in the older and younger patients (p < 0.05). After 12 months, HbA1c dropped below 6.5% in 89% of patients younger and in 81% of patients older than 60 (p = 0.11). There was no mortality in either group, but there were significantly more complications and there was a longer hospital stay in the older patients.

CONCLUSION

RY gastric bypass comes with a significantly higher morbidity and hospital stay in older patients, but weight loss and improvement of DM are similar as in the younger patients.

Achieving Weight Loss and Hypertension Control Among Obese Adults: A US Multidisciplinary Group Practice Observational Study

BACKGROUND

Among adults with hypertension, obesity independently contributes to cardiovascular disease. Weight loss and hypertension control are critical to reduce cardiovascular events. The purpose of this study was to evaluate rates and predictors of achieving weight loss among adults who achieved hypertension control within 1 year of developing incident hypertension.

METHODS

Retrospective electronic health record analysis was performed of ≥18 year olds with a body mass index ≥30.0kg/m(2), who received regular primary care from 2008 to 2011 and achieved hypertension control. Exclusions were less than 60 days follow-up, prior hypertension diagnosis, prior antihypertensive prescription, or pregnancy. The primary outcome was clinically significant weight loss (≥5kg); the secondary outcome was modest (2.0-4.9kg) weight loss. Multinomial logistic regression identified predictors of achieving weight loss (≥5 or 2.0-4.9kg) compared to no significant weight loss (<2kg).

RESULTS

Of the 2,906 obese patients who achieved hypertension control, 72% (n = 2,089) did not achieve at least 2.0kg weight loss. Overall, 12% (n = 351) achieved ≥5kg weight loss. Young adults (18-39 year olds; odds ratio (OR): 2.47, 95% confidence interval (CI): 1.63-3.47), middle-aged adults (40-59 year olds; OR: 2.32, 95% CI: 1.59-3.37), and patients prescribed antihypertensive medication (OR: 1.37, 95% CI: 1.07-1.76) were more likely to achieve clinically significant weight loss and hypertension control. Age remained a significant predictor for 2.0-4.9kg weight loss.

CONCLUSIONS

Despite achieving hypertension control, the majority of obese patients did not achieve clinically significant weight loss. Effective weight loss interventions with dedicated hypertension treatment are needed to decrease cardiovascular events in this high-risk population.

Association of body mass index with all-cause mortality in patients with diabetes: a systemic review and meta-analysis

BACKGROUND

The obesity paradox phenomenon has been found in different populations, such as heart failure and coronary heart disease, which suggest that patients with established cardiovascular disease (CVD) and with normal weight had higher risk of mortality than those with overweight or obesity. However, the obesity paradox is controversial among patients with diabetes which has been considered as the coronary heart disease equivalent. The aim of our study was to summarize current findings on the relationship between body mass index (BMI) and all-cause mortality in patients with diabetes and make a meta-analysis.

METHODS

We searched previous studies from MEDLINE, EMBASE, and the Cochrane databases using the keywords: BMI, mortality, diabetes, and obesity paradox or reverse epidemiology. Finally, sixteen studies were identified and 385,925 patients were included. Patients were divided into five groups based on BMI (kg/m(2)) levels: underweight (<18.5), normal weight (18.5-24.9), overweight (25-29.9), mild obesity (30-34.9), and morbid obesity (>35). A random effect meta-analysis was performed by the inverse variance method.

RESULTS

As compared with the normal weight, the underweight had higher risk of mortality [hazard ratio (HR): 1.59, 95% confidence interval (CI): 1.32-1.91]. In contrast, the overweight and the mild obesity had lower risk of mortality than the normal weight (HR: 0.86, 95% CI: 0.78-0.96, and 0.88, 95% CI: 0.78-1.00, respectively), but the morbid obesity did not (HR: 0.99, 95% CI: 0.84-1.16). In addition, the subgroup analysis by sex showed that the overweight had the lowest mortality as compared with the normal weight (HR: 0.82, 95% CI: 0.74-0.90) and the obesity in males, but the risk of mortality did not differ among groups in females. Notably, the heterogeneity was significant in most of group comparisons.

CONCLUSIONS

Our meta-analysis showed a U-shaped relationship between BMI and all-cause mortality in patients with diabetes. The significant heterogeneity among studies suggested that many confounders such as sex difference may affect the association.

Determinants of mortality in patients with type 2 diabetes: a review

We aimed to review and summarize the evidence from accomplished trials analyzing factors influencing mortality in patients with T2DM and to provide some recommendations for targets and treatment in the European region. The following databases were searched for relevant trials: PubMed and the Cochrane Library. Of 3.806 citations, 134 trials met our inclusion criteria.

RESULTS

The reduction in lifetime for 65 + -years-old patients having less than 10 years T2DM amounts to 1.8 years. Having T2DM for more than 10 years lifetime will be reduced by 2.7 years. However, the lifetime shortening factor of T2DM will even be stronger for 40 + -years-old patients at onset. Males will lose 11.6 years of life and 18.6 QUALYs. T2DM among females will reduce life by 14 QUALYs by 22 years. From a statistical point of view, the highest mortality rate will occur in an over 55-years-old European smoking and non-compliant diabetic woman with alcohol abuse living in a rural area with a low level of education and a low socio-economic status. Furthermore, other co-morbidities such as cardiovascular diseases, gout, and depression affect mortality. Additionally, mortality will increase with a BMI over 35 and also with a BMI under 20-25. This refers to the obesity paradox indicating a higher mortality rate among normal weight patients with T2DM compared to overweight patients with T2DM. HbA1c-levels between 6.5 % and 7 % are associated with the lowest impact on mortality.

Excessive Weight Gain during the First Year of Peritoneal Dialysis Is Associated with Inflammation, Diabetes Mellitus, and a Rapid Decrease in Residual Renal Function

OBJECTIVES

Significant weight gain is a potential problem in most patients starting peritoneal dialysis (PD); however, few studies have explored the clinical effects of increased body weight (BW) in these patients. We evaluated the effect of excess weight gain during the first year after PD on residual renal function (RRF).

METHODS

A total of 148 incident PD patients were analyzed in a longitudinal observational study. The mean duration of follow-up was 23.8 months. RRF was measured at baseline (within 1 month of starting PD) and thereafter at 6-month intervals for 2-3 years or until loss of RRF. BW was measured at the time of RRF measurement, and excess weight gain was defined as a BW increase over the median value (3.0%).

RESULTS

The median 1-year increase in BW was 2.3kg (IQR, 1.01-4.58) or 3.0% (IQR, 1.13-5.31). The mean slope of RRF decline was -0.068 ± 0.053 mL/min/month/1.73m2, and RRF loss developed in 48 patients at a mean follow-up time of 19.4 ± 6.8 months. Patients with BW increases > 3.0% showed significantly increased RRF decline rate compared to those without excess weight gain (p<0.001), and the BW increase (%/year) correlated significantly with higher hs-CRP levels and RRF decline rate. High systolic blood pressure, diabetes, large amount of proteinuria and excess BW gain significantly influenced the RRF decline rate. Also, it increased the risk of RRF loss by 4.17-fold (95% confidence intervals, 1.87-9.28; p<0.001).

CONCLUSIONS

Excess weight gain during the first year of PD was closely linked to systemic inflammation, diabetes and rapid decline in RRF.