The obesity-survival paradox in hemodialysis patients: why do overweight hemodialysis patients live longer?

Improving glycemic control: transitioning from dulaglutide to tirzepatide in patients with type 2 diabetes undergoing hemodialysis

Background: Tirzepatide-a dual glucose-dependent insulinotropic peptide and glucagon-like peptide-1 receptor agonist-is used to treat type 2 diabetes. However, the efficacy and safety of tirzepatide in patients undergoing hemodialysis remain unclear. Methods: We conducted a single-center retrospective study of patients with type 2 diabetes undergoing hemodialysis who were transitioned from dulaglutide to tirzepatide. We continuously monitored glucose levels in patients undergoing hemodialysis before and after switching from dulaglutide to tirzepatide. Results: Fourteen patients (mean age: 61.9 ± 9.9 years, male: female = 11:3) were included in this study. After switching to tirzepatide, time in range increased to 50.8% from 42.7% (p = 0.02), time above range decreased to 37.8% from 48.4% (p = 0.02), and mean glucose levels decreased to 137.4 mg/dL from 156.6 mg/dL (p = 0.006). In contrast, there was no significant difference in time below range before and after tirzepatide administration (11.3% and 8.9%) (p = 0.75). Three patients experienced dyspepsia (21.4%), and one patient experienced nausea (7.1%); however, no critical adverse events were reported. Conclusion: Transitioning from dulaglutide to tirzepatide improved glycemic control without increasing hypoglycemia in patients undergoing hemodialysis for type 2 diabetes.

Sarcopenic obesity and its relation with muscle quality and mortality in patients on chronic hemodialysis

BACKGROUND & AIMS

Sarcopenia is prevalent in patients with end-stage kidney disease (ESKD) on hemodialysis (HD), and is associated with poor outcomes, while obesity may be protective. Sarcopenic obesity is associated with increased frailty, morbidity and mortality in the general population. Myosteatosis, i.e., muscle fat infiltration, has major effects on muscle strength and physical performance, but is poorly investigated in the nephrology setting. In the present study we aimed to assess the association between sarcopenic obesity, as diagnosed by abdominal CT, and mortality. Moreover, the relationship between myosteatosis, sarcopenic obesity and mortality was also investigated.

METHODS

This is a retrospective study in which ESKD patients on HD submitted to unenhanced abdominal CT for clinical reasons at least 6 months after dialysis initiation were evaluated for sarcopenic obesity and myosteatosis, defined as intermuscular fat area and low attenuation muscle area. Sarcopenic obesity was diagnosed in cases of low abdominal skeletal muscle area and high total fat area. Receiver-operating characteristics (ROC) analysis with Youden index was used to determine the cut-off for high total fat area. Intermuscular fat area and low attenuation muscle area were evaluated by applying the Hounsfield unit of interest (-190; -30, and -29; +29 respectively). Cox regression analysis was used to evaluate the association between predictors and mortality risk.

RESULTS

We enrolled 212 patients, aged 68.8 (±14.7) years, 65.5% (139/212) male. Median follow-up was 19.7 (interquartile range [IQR] 2.7-35) months. Sarcopenic obesity was diagnosed in 19.8% of patients and was associated with increased mortality (HR: 3.29 (1.72; 6.27), P < 0.001), and with the presence of myosteatosis. Both intermuscular fat area and low attenuation muscle area were associated with increased mortality in adjusted analyses.

CONCLUSIONS

Patients with sarcopenic obesity have increased myosteatosis. Sarcopenic obesity and myosteatosis are associated with increased mortality in patients on HD.

Waist-to-height ratio and dynapenic abdominal obesity in users of hemodialysis services

BACKGROUND AND AIMS

Abdominal obesity and decreased muscle strength are risk factors for individuals on hemodialysis. Thus, the combination of these two factors known as dynapenic abdominal obesity acts as an important marker of the nutritional status of this population. Therefore, the objective of the work was to investigate the association between abdominal obesity, dynapenia, and sociodemographic, clinical, and nutritional factors in individuals with chronic kidney disease undergoing hemodialysis.

METHODS AND RESULTS

Cross-sectional study with 940 individuals undergoing hemodialysis in southeastern Brazil. Dynapenic abdominal obesity was defined by the combination of the presence of abdominal obesity, indicated by the waist-to-height ratio, and the reduction in muscle strength, measured by handgrip strength. Binary logistic regression was performed to calculate the odds ratio (OR) and the respective confidence intervals (95% CI). Dynapenic abdominal obesity was present in 45.42% of the study population. We found that being 18-59 years (OR: 3.17; 95% CI 2.35-4.28; p < 0.001) and being overweight (OR: 2.58; 95% CI 1.92-3.47; p < 0.001) increased the chances for the presence of dynapenic abdominal obesity; however, the habit of consuming meals away from home (OR: 0.63; 95% CI 0.47-0.85; p = 0.003) and having preserved behavioral adductor muscle thickness (OR: 0.52; 95% CI 0.38-0.71; p < 0.001) are considered protective factors.

CONCLUSION

Dynapenic abdominal obesity, present in individuals on hemodialysis, may represent a valid nutritional tool for assessing cardiovascular risk and mortality in this population, in order to implement the most effective preventive and/or therapeutic intervention possible.

The Impact of BMI Changes on the Incidence of Glomerular Hematuria in Korean Adults: A Retrospective Study Based on the NHIS-HEALS Cohort

Obesity and recurrent hematuria are known risk factors for chronic kidney disease. However, there has been controversy on the association between obesity and glomerular hematuria. This study aimed to investigate the association between body mass index (BMI) and weight change and recurrent and persistent hematuria in glomerular disease using a large-scale, population-based Korean cohort. Data were collected from the National Health Insurance Service-National Health Screening Cohort. Cox proportional hazards regression analysis was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for recurrent and persistent hematuria in glomerular disease according to the BMI group. Compared with the BMI 23-25 kg/m² group, the HR (95% CI) for incident recurrent and persistent hematuria in glomerular disease was 0.921 (0.831-1.021) in the BMI <23 kg/m² group, 0.915 (0.823-1.018) in the BMI 25-30 kg/m² group, and 1.151 (0.907-1.462) in the BMI ≥30 kg/m² group. Compared with the stable weight group, the HRs (95% CIs) for incident recurrent and persistent hematuria in glomerular disease were 1.364 (1.029-1.808) and 0.985 (0.733-1.325) in the significant weight loss and gain groups, respectively. Despite adjusting for confounders, this result remained significant. Baseline BMI was not associated with the risk of incident recurrent and persistent hematuria in glomerular disease. Weight loss greater than 10% was associated with the incidence of recurrent and persistent hematuria in glomerular disease. Therefore, maintaining an individual's weight could help prevent recurrent and persistent hematuria in glomerular disease in middle-aged and older Korean adults.

Associations of body mass index, fasting insulin, and inflammation with mortality: a prospective cohort study

BACKGROUND/OBJECTIVES

Obesity is often considered to increase the risk for premature mortality. Higher fasting insulin and c-reactive protein are associated with higher body mass index (BMI) and all-cause mortality, so may confound the association between obesity and mortality. Our objective was to determine the independent associations between BMI, fasting insulin, c-reactive protein, and all-cause mortality in a general population sample.

METHODS

This prospective cohort study included non-institutionalized US adults (≥20 years) from the National Health and Nutrition Examination Surveys 1999-2000 to 2013-2014. The main exposures of interest were BMI, fasting insulin, c-reactive protein. Mortality data were obtained through linking participants to the National Death Index (ending December 31, 2015).

RESULTS

There were 12,563 participants with a median age of 45 years (range 20-85) and 47.9% were male. The median BMI was 27 kg/m² (IQR 24-32), median fasting insulin was 54 pmol/L (IQR 35-87), and median c-reactive protein was 1.9 mg/L (IQR 0.8-4.4). In a Cox model adjusted for age, biological sex, cigarette smoking, and ten chronic conditions, higher BMI parameterized with quadratic and linear terms was not associated with mortality. When fasting insulin and the natural logarithm of c-reactive protein were included in the model, an inverse association between BMI and mortality was present (compared to the referent category of 5th percentile: 1st percentile, HR 1.10, 95% CI 1.06-1.13; 99th percentile, HR 0.48, 95% CI 0.34-0.69). In contrast, higher levels of fasting insulin and c-reactive protein were associated with an increased risk of mortality (for fasting insulin: 1st percentile, HR 0.98, 95% CI 0.97-0.99; 99th percentile, HR 1.83, 95% CI 1.48-2.26; for c-reactive protein, 1st percentile, HR 0.87, 95% CI 0.84-0.90; 99th percentile, HR 2.77, 95% CI 2.12-3.62).

CONCLUSIONS

Higher fasting insulin and higher c-reactive protein confound the association between BMI and the risk of all-cause mortality. The increase in mortality that has been attributed to higher BMI is more likely due to hyperinsulinemia and inflammation rather than obesity.

Impact of Extremes of Body Mass Index (BMI) in End-Stage Renal Disease (ESRD) Patients

The principal objective of this systematic review is to determine the prognosis of end-stage renal disease (ESRD) patients on maintenance hemodialysis with high body mass index (BMI) and study the potential mechanisms behind it. PubMed and Google Scholar electronic databases covering the period of the last 30 years 1992 to 2022 are searched thoroughly and a total of 11 articles were finally selected for the study. Reference lists of included papers are also searched. Each paper was examined by two independent evaluators who also extracted data from full papers. The quality of the selected studies was assessed by different quality assessment tools and only moderate- to high-quality papers are included.

In this systematic review, we studied different mechanisms explaining the obesity paradox in patients on maintenance hemodialysis, i.e., hemodynamic stability, the concentration of TNF-α receptors, neurohumoral response, role of inflammation, blood pressure, etc. also, the effect of age, gender, duration of treatment, acetyl-ghrelin on obesity paradox have been considered in our paper. This systematic review demonstrates the evidence of an inverse relationship between BMI and all-cause mortality in ESRD patients on maintenance hemodialysis.

Obesity survival paradox in patients hospitalized with community-acquired pneumonia. Assessing sex-differences in a population-based cohort study

AIM

To assess the effect of obesity status (no obesity/obesity/ morbid obesity) on hospital outcomes (length of hospital stay [LOHS] and in-hospital mortality [IHM]), among patients hospitalized with community-acquired pneumonia (CAP) and according to sex.

METHODS

We conducted a retrospective cohort study based on national hospital discharge data of all subjects aged≥ 18 years hospitalized with CAP in Spain from 2016 to 2019.

RESULTS

We identified 519,750 hospital discharges with CAP. The prevalence of obesity was 6.38% and 1.78%. for morbid obesity. The mean age was higher for patients without obesity followed by those with obesity and morbid obesity (74.61, 72.5 and 70.2 years respectively; p<0.001). The mean number of comorbidities was similar for patients with obesity and morbid obesity (2.30 and 2.29) and significantly higher than for non-obese individuals (2.10). The crude IHM was higher among the non-obese patients (12.71%) followed by those with morbid obesity (8.56%) and obesity (7.72%), without finding differences between men and women. Among men, after multivariable logistic regression analysis, the probability of dying in the hospital was significantly lower for those with obesity (Adjusted-OR 0.59;95%CI 0.55-0.63) and morbid obesity (Adjusted-OR 0.62;95%CI 0.54-0.71) compared with non-obese. The protective effect of obesity (Adjusted-OR 0.71;95%CI 0.67-0.75) and morbid obesity (Adjusted OR 0.73;95%CI 0.66-0.8) was also observed among women.

CONCLUSIONS

Obese and obesity morbid patients with CAP have a lower risk of IHM than non-obese patients, without sex differences in this association. These data confirm the existence of the obesity paradox in this patient population.

The Effects of Body Mass Index on In-hospital mortality following first ischemic or hemorrhagic stroke events: Does the "obesity paradox" apply?

BACKGROUND

While it is widely held that obesity is a risk factor for stroke, its role in mortality after stroke is less understood. We aim to examine effects of Body Mass Index (BMI) on in-hospital mortality after non-subarachnoid, subarachnoid, and ischemic stroke.

METHODS

Retrospective cohort study. Patients aged ≥18 years, who were hospitalized in Florida hospitals between 2008 and 2012 with a diagnosis of first-time stroke as reported by the Agency for Health Care Administration (AHCA). The main independent variable was BMI category, which was divided into non-overweight/non-obese, obese, and morbidly obese. The primary outcome was the adjusted odds ratio (aOR) for in-hospital mortality for subarachnoid and non-subarachnoid hemorrhagic stroke, and ischemic stroke. Logistic regression modeling was utilized to examine the association between each BMI category and in-hospital mortality, while controlling for several potential confounders. This study was reported in line with the STROCSS criteria.

RESULTS

Of the 333,367 patients included in the database, 150,153 (45.0%) patients met inclusion criteria. After adjusting for age, gender, ethnicity and other possible confounders, obese patients were 21% less likely to die during their hospitalization following a first ischemic stroke (0.79 aOR, 0.69-0.92, 95% CI, p = 0.002), and 32% less likely following a first non-subarachnoid hemorrhage (0.68 aOR, 0.57-0.82, 95% CI, p = 0.0001) compared to non-overweight/non-obese counterparts.

CONCLUSION

Obese patients are less likely to die during hospitalization following first-time non-subarachnoid hemorrhage and ischemic stroke than non-overweight/non-obese patients. These findings support the "obesity paradox" concept, though more research is needed for recurrent stroke patients.

Obesity and risk of age-related eye diseases: a systematic review of prospective population-based studies

BACKGROUND

Obesity is a public health challenge worldwide. The relationship between obesity and age-related eye diseases including cataract, glaucoma, age-related macular degeneration (AMD) and diabetic retinopathy (DR) have remained elusive.

DESIGN AND METHODS

We conducted a systematic review of three electronic databases for longitudinal population-based studies that described associations between measures of obesity including body mass index (BMI), waist-circumference (WC), and waist-to-hip ratio (WHR), and age-related eye diseases.

RESULTS

Our search yielded 1731 articles, of which 14, 10, 16 and 8 articles met our eligibility criteria for cataract, glaucoma, AMD and DR, respectively. BMI-defined obesity was positively associated with incident cataract, incident AMD and incident DR in Western populations, but in Asian populations associations for incident AMD were not significant and associations for incident DR were inverse. WC-defined obesity was associated with incident glaucoma in non-Western populations. WHR-defined obesity but not BMI-defined obesity was associated with the incidence or progression of AMD in two Western studies.

CONCLUSIONS

Overall, we found strong evidence supporting associations between obesity and age-related eye diseases. Further research on the association of abdominal obesity and effect of weight loss and physical activity on age-related eye diseases is warranted to support clinical and public health recommendations.

Temporal Associations Among Body Mass Index, Fasting Insulin, and Systemic Inflammation: A Systematic Review and Meta-analysis

IMPORTANCE

Obesity is associated with a number of noncommunicable chronic diseases and is purported to cause premature death.

OBJECTIVE

To summarize evidence on the temporality of the association between higher body mass index (BMI) and 2 potential mediators: chronic inflammation and hyperinsulinemia.

DATA SOURCES

MEDLINE (1946 to August 20, 2019) and Embase (from 1974 to August 19, 2019) were searched, although only studies published in 2018 were included because of a high volume of results. The data analysis was conducted between January 2020 and October 2020.

STUDY SELECTION AND MEASURES

Longitudinal studies and randomized clinical trials that measured fasting insulin level and/or an inflammation marker and BMI with at least 3 commensurate time points were selected.

DATA EXTRACTION AND SYNTHESIS

Slopes of these markers were calculated between time points and standardized. Standardized slopes were meta-regressed in later periods (period 2) with standardized slopes in earlier periods (period 1). Evidence-based items potentially indicating risk of bias were assessed.

RESULTS

Of 1865 records, 60 eligible studies with 112 cohorts of 5603 participants were identified. Most standardized slopes were negative, meaning that participants in most studies experienced decreases in BMI, fasting insulin level, and C-reactive protein level. The association between period 1 fasting insulin level and period 2 BMI was positive and significant (β = 0.26; 95% CI, 0.13-0.38; I2 = 79%): for every unit of SD change in period 1 insulin level, there was an ensuing associated change in 0.26 units of SD in period 2 BMI. The association of period 1 fasting insulin level with period 2 BMI remained significant when period 1 C-reactive protein level was added to the model (β = 0.57; 95% CI, 0.27-0.86). In this bivariable model, period 1 C-reactive protein level was not significantly associated with period 2 BMI (β = -0.07; 95% CI, -0.42 to 0.29; I2 = 81%).

CONCLUSIONS AND RELEVANCE

In this meta-analysis, the finding of temporal sequencing (in which changes in fasting insulin level precede changes in weight) is not consistent with the assertion that obesity causes noncommunicable chronic diseases and premature death by increasing levels of fasting insulin.

Bariatric Surgery and Long-term Survival in Patients With Obesity and End-stage Kidney Disease

Importance

Obesity rates in patients with end-stage kidney disease are rising, contribute to excess morbidity, and limit access to kidney transplant. Despite this, there continues to be controversy around the use of bariatric surgery in this patient population.

Objective

To determine whether bariatric surgery is associated with improvement in long-term survival among patients with obesity and end-stage kidney disease.

Design, Setting, and Participants

Retrospective cohort study and secondary analysis of previously collected data from the United States Renal Data System registry (2006-2015). We used Cox proportional hazards analysis to evaluate differences in outcomes for patients receiving bariatric surgery (n = 1597) compared with a matched cohort of nonsurgical patients (n = 4750) receiving usual care. Data were analyzed between September 3, 2019, and November 13, 2019.

Exposure

Receipt of bariatric surgery.

Main Outcomes and Measures

All-cause mortality at 5 years. Secondary outcomes included disease-specific mortality and incidence of kidney transplant.

Results

Surgical and nonsurgical control patients had similar age, demographics, and comorbid disease burden. The mean (SD) age was 49.8 (11.2) years for surgical patients vs 51.7 (11.1) years for nonsurgical patients. Six hundred fifteen surgical patients (38.5%) were black vs 1833 nonsurgical patients (38.6%). Surgery was associated with lower all-cause mortality at 5 years compared with usual care (cumulative incidence, 25.6% vs 39.8%; hazard ratio, 0.69, 95% CI, 0.60-0.78). This was driven by lower mortality from cardiovascular causes at 5 years for patients undergoing bariatric surgery compared with nonsurgical control patients (cumulative incidence, 8.4% vs 17.2%; hazard ratio, 0.51; 95% CI, 0.41-0.65). Bariatric surgery was also associated with an increase in kidney transplant at 5 years (cumulative incidence, 33.0% vs 20.4%; hazard ratio, 1.82; 95% CI, 1.58-2.09). However, at 1 year, bariatric surgery was associated with higher all-cause mortality compared with usual care (cumulative incidence, 8.6% vs 7.7%; hazard ratio, 1.45; 95% CI, 1.13-1.85).

Conclusions and Relevance

Among patients with obesity and end-stage kidney disease, bariatric surgery was associated with lower all-cause mortality compared with usual care. Bariatric surgery was also associated with an increase in kidney transplant. Bariatric surgery may warrant further consideration in the treatment of patients with obesity and end-stage kidney disease.

Neck Circumference Is Associated With Poor Outcome in Patients With Spontaneous Intracerebral Hemorrhage

Objective: This study aimed to assess the association between neck circumference (NC) and functional outcome in intracerebral hemorrhage (ICH) patients.

Methods: We prospectively analyzed data from ICH patients who received treatment at our institution from January 2018 to November 2019. Patients were categorized into two groups according to 180-day modified Rankin scale (MRS) scores. Univariate and multivariate analyses were performed to assess whether NC was associated with poor outcome in ICH patients. Receiver operating characteristic (ROC) curve analysis was performed to determine the significance of NC in predicting the functional outcome of ICH patients.

Results: A total of 312 patients were enrolled in our study. Multivariate logistic regression analysis indicated that NC was an independent predictor of poor 180-day functional outcome [odds ratio (OR) = 1.205, 95% confidence interval (CI): 1.075–1.350, p = 0.001]. ROC analysis revealed that NC could predict poor functional outcome at 6 months.

Conclusions: NC is an independent predictor of unfavorable functional outcome at 6 months in ICH patients.

Obesity and cardiovascular disease in women

As the prevalence of obesity continues to grow worldwide, the health and financial burden of obesity-related comorbidities grows too. Cardiovascular disease (CVD) is clearly associated with increased adiposity. Importantly, women are at higher risk of CVD when obese and insulin resistant, in particular at higher risk of developing heart failure with preserved ejection fraction and ischemic heart disease. Increased aldosterone and mineralocorticoid receptor activation, aberrant estrogenic signaling and elevated levels of androgens are among some of the proposed mechanisms explaining the heightened CVD risk. In addition to traditional cardiovascular risk factors, understanding nontraditional risk factors specific to women, like excess weight gain during pregnancy, preeclampsia, gestational diabetes, and menopause are central to designing personalized interventions aimed to curb the epidemic of CVD. In the present review, we examine the available evidence supporting a differential cardiovascular impact of increased adiposity in women compared with men and the proposed pathophysiological mechanisms behind these differences. We also discuss women-specific cardiovascular risk factors associated with obesity and insulin resistance.

Higher body mass index is not a risk factor for in-hospital adverse outcomes following total knee arthroplasty

PURPOSE

To investigate the association between body mass index (BMI) and perioperative complications until hospital discharge, following primary total knee arthroplasty (TKA).

METHODS

This retrospective study reviewed 1665 cases of elective primary unilateral TKA performed between 2006 and 2010, from a prospective secure electronic database. Types of complications, length of operating time, and duration of hospital stay were analyzed in both adjusted (for known confounders) and unadjusted analyses. A further matched analysis was also performed.

RESULTS

In terms of overall complications, there was no statistically significant difference between the BMI categories. When individual obesity category was considered, obese 2 had the lowest odds of developing complications, both with unadjusted (odds ratio (OR): 0.61, 95% confidence interval (CI) 0.41-0.91, p < 0.015) and adjusted regression analysis (OR: 0.65, 95% CI: 0.43-0.99, p = 0.044). Compared to normal weight category, obese class 3 (≥40 kg/m²) individuals were at 66% (OR: 0.34, 95% CI: 0.21-0.55) lower (unadjusted) odds of developing cardiac complications (overall p < 0.001). With the matched analysis, compared to normal weight category, obese class 3 (≥40 kg/m²) individuals were at a 60% (OR: 0.40, 95% CI: 0.23-0.68) lower (unadjusted) odds of developing cardiac complications (overall p = 0.004). Obese 3 patients had significantly higher operating time compared with other groups ( p < 0.001).

CONCLUSION

This study did not find a significant association between BMI and increased overall in-hospital medical or surgical complications following primary TKA. Obesity significantly increased the length of operating time.

Body mass index and clinical outcomes in patients after ischaemic stroke in South Korea: a retrospective cohort study

OBJECTIVES

Although obesity is a risk factor for stroke, its impact on mortality in patients with stroke remains unclear. In this study, we aimed to evaluate the relationship between body mass index (BMI) and mortality due to ischaemic stroke among adults aged 20 years and above in Korea.

DESIGN

Retrospective cohort study.

SETTING

A tertiary-hospital-based stroke registry linked to the death records.

PARTICIPANTS

3599 patients admitted for ischaemic stroke from January 2007 to June 2013.

OUTCOME MEASURES

The HRs for all-cause and stroke-related mortality were calculated using Cox proportional hazards models. Progression from stroke-related mortality was assessed using the Fine-Grey competing risk model, treating other-cause mortality as a competing risk. Adjustments were made for age, gender, smoking status, Charlson comorbidity index, cardiovascular or non-cardiovascular comorbidities, stroke severity, severity related to other medical conditions, complications and enrolment year. We repeated the analysis with stratification based on age groups (less than 65 vs 65 years and above).

RESULTS

For stroke-related mortality, there was no significant difference among the four BMI groups. The risk of all-cause mortality was 36% higher in the underweight group than in the normal weight group (long-term HR=1.36, 95% CI: 1.04 to 1.79), whereas the mortality risk of the obese group was significantly lower (HR=0.66, 95% CI: 0.54 to 0.81). Although this relationship was not estimated in the younger group, it was found that obesity had a protective effect on the all-cause mortality in the elderly (long-term HR=0.66, 95% CI: 0.52 to 0.83).

CONCLUSIONS

Obesity is more likely to reduce mortality risk than normal weight, especially in elderly patients.

The Plausibility of Obesity Paradox in Cancer-Point

In contrast to the convincing evidence that obesity (measured by body mass index, BMI) increases the risk of many different types of cancer, there is an ambiguity in the role of obesity in survival among cancer patients. Some studies suggested that higher BMI decreased mortality risk in cancer patients, a phenomenon called the obesity paradox. The spurious positive association between BMI and cancer survival is likely to be explained by several methodologic limitations including confounding, reverse causation, and collider stratification bias. Also, the inadequacy of BMI as a measure of body fatness in cancer patients commonly experiencing changes in body weight and body composition may have resulted in the paradox. Other factors contributing to the divergent results in literature are significant heterogeneity in study design and method (e.g., study population, follow-up length); time of BMI assessment (pre-, peri-, or post-diagnosis); and lack of consideration for variability in the strength and directions of associations by age, sex, race/ethnicity, and cancer subtype. Robust but practical methods to accurately assess body fatness and body compositions and weight trajectories in cancer survivors are needed to advance this emerging field and to develop weight guidelines to improve both the length and the quality of cancer survival. Cancer Res; 78(8); 1898-903. ©2018 AACR.

The impact of BMI extremes on disease-free survival and overall survival following cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

Background

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are increasingly being offered to patients with peritoneal carcinomatosis (PC). On the other hand, the prevalence of obesity is also increasing and expected to reach unprecedented rates in the upcoming decades. Therefore, managing patients on either extreme of the body mass index (BMI) range is anticipated to become a routine challenge and it becomes imperative to understand the impact of BMI, as a spectrum, on the long-term outcomes of CRS and HIPEC. We aim to study the short and long-term outcomes of CRS and HIPEC in patients on both extremes of the BMI spectrum.

Methods

Patients with PC who underwent CRS and HIPEC over 10 years for ovarian, colorectal, and pseudomyxoma peritonei (PMP), and whose BMI was recorded were retrospectively included. Patients were divided based on their weight strata. The primary outcomes were disease-free survival (DFS) and overall survival (OS).

Results

A total of 126 patients were included. Fifty-seven point one percent were females and mean age was 59.31±1.57 years. No difference was noted between the groups in regards to demographics, perioperative characteristics, and immediate postoperative outcomes. Underweight group had a trend toward a higher peritoneal cancer index and lower rates of complete cytoreduction. Optimum BMI for OS and DFS was in the obesity range in colorectal PC, in the overweight range in ovarian PC, and in borderline obesity in PMP. Regression analysis identified underweight as an independent risk factor for shorter DFS, whereas underweight and morbid obesity were risk factors for shorter OS, after adjustment for other factors such as incomplete cytoreduction, tumor histology, and grade.

Conclusions

OS and DFS vary across the BMI strata. Ovarian PC demonstrates earlier recurrence and shorter survival, whereas colorectal PC demonstrates the "obesity paradox" as patients move into the realm of obesity. BMI extremes, low or high, generally carry a poor prognosis for OS.

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.

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.

Weight Loss in Advanced Chronic Kidney Disease: Should We Consider Individualised, Qualitative, ad Libitum Diets? A Narrative Review and Case Study

In advanced chronic kidney disease, obesity may bring a survival advantage, but many transplant centres demand weight loss before wait-listing for kidney graft. The case here described regards a 71-year-old man, with obesity-related glomerulopathy; referral data were: weight 110 kg, Body Mass Index (BMI) 37 kg/m², serum creatinine (sCr) 5 mg/dL, estimated glomerular filtration rate (eGFR) 23 mL/min, blood urea nitrogen (BUN) 75 mg/dL, proteinuria 2.3 g/day. A moderately restricted, low-protein diet allowed reduction in BUN (45–55 mg/dL) and good metabolic and kidney function stability, with a weight increase of 6 kg. Therefore, he asked to be enrolled in a weight-loss program to be wait-listed (the two nearest transplant centres required a BMI below 30 or 35 kg/m²). Since previous low-calorie diets were not successful and he was against a surgical approach, we chose a qualitative, ad libitum coach-assisted diet, freely available in our unit. In the first phase, the diet is dissociated; he lost 16 kg in 2 months, without need for dialysis. In the second maintenance phase, in which foods are progressively combined, he lost 4 kg in 5 months, allowing wait-listing. Dialysis started one year later, and was followed by weight gain of about 5 kg. He resumed the maintenance diet, and his current body weight, 35 months after the start of the diet, is 94 kg, with a BMI of 31.7 kg/m², without clinical or biochemical signs of malnutrition. This case suggests that our patients can benefit from the same options available to non-CKD (chronic kidney disease) individuals, provided that strict multidisciplinary surveillance is assured.

Interaction of Physical Activity and Body Mass Index on Mortality in Coronary Heart Disease: Data from the Nord-Trøndelag Health Study

OBJECTIVE

The role of physical activity in the relationship between body mass index (BMI) and survival in coronary heart disease is unclear. Our aim was to examine the isolated and combined associations among BMI, physical activity, and mortality in subjects with coronary heart disease.

METHODS

A total of 6493 participants (34.4% were women) with coronary heart disease from the Nord-Trøndelag Health Study, with examinations in 1986, 1996, and 2007, were followed to the end of 2014. We calculated hazard ratios (HRs) for all-cause and cardiovascular disease mortality, estimated using Cox proportionate hazard regression adjusted for age, smoking, diabetes, hypertension, self-reported health status, and alcohol.

RESULTS

A total of 3818 patients died (62.1% of cardiovascular disease) during 30 (median 12.5) years of follow-up. Compared with a BMI of 18.5 to 22.4 kg/m², BMI categories of 25.0 to 27.4 kg/m², 27.5 to 29.9 kg/m², and 30.0 to 34.9 kg/m² had reduced all-cause mortality risk: HR, 0.80; 95% confidence interval (CI), 0.72-0.90; HR, 0.80; 95% CI, 0.71-0.90; HR, 0.83; 95% CI, 0.74-0.95, respectively. The BMI categories 25.0 to 27.4 kg/m² and 27.5 to 29.9 kg/m² had reduced cardiovascular disease mortality risk: HR, 0.81; 95% CI, 0.70-0.94; HR, 0.83; 95% CI, 0.71-0.96, respectively. Compared with physically inactive, all levels of physical activity were associated with reduced all-cause and cardiovascular disease mortality risk. In physically inactive, all BMI categories >25.0 kg/m² had reduced all-cause mortality risk (HRs across BMI categories: 0.77, 0.79, 0.79, 0.74), whereas in subjects who were following or exceeding the recommended level of physical activity, BMI was not associated with survival.

CONCLUSIONS

Overweight and obese subjects with coronary heart disease had reduced all-cause and cardiovascular disease mortality, but such an obesity paradox was seen only in participants who did not adhere to current recommendations of physical activity.

Reexamining the Association of Body Mass Index With Overall Survival Outcomes After Liver Transplantation

BACKGROUND

Several studies have shown that obese patients undergoing liver transplantation (LT) have an increased risk of mortality regardless of Model of End Stage Liver Disease (MELD) scores. The purpose of this study is to identify the range of body mass index (BMI) at LT associated with the lowest risks of posttransplant mortality by MELD category.

METHODS

A retrospective cohort of patients aged 18 years or older from the Organ Procurement and Transplantation Network database undergoing LT between February 27, 2002, and December 31, 2013, was identified and followed up through March 14, 2014. Patients' MELD score at the time of transplantation was categorized into 10 or lower (MELD1), 11 to 18 (MELD2), 19 to 24 (MELD3), and 25 or higher (MELD4). Multivariable adjusted Cox proportional hazard analyses were conducted.

RESULTS

Among 48 226 patients in the analytic cohort (14.8% were in MELD1, 33.7% were in MELD2, 19.6% were in MELD3, and 32.0% were in MELD4), 25% died with mean follow-up of 1371 days. For MELD1, patient BMI ranging from 30 to 33 was associated with a better survival outcome than BMI less than 30 or 33 or greater; for MELD2, BMI ranging from 28 to 37 had a better survival outcome than BMI less than 28 or 37 or greater; for MELD3, the survival outcome improved with an increasing BMI; for MELD4, the survival outcome was not associated with patient BMI.

CONCLUSIONS

This study provides evidence that obesity in LT patients is not necessarily associated with higher posttransplantation mortality and highlights the importance of the interaction between BMI and MELD category to determine their survival likelihood.

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.

Medical Weight Loss Treatment Options in Obese Solid-Organ Transplant Candidates

With the increasing incidence of obesity in our country, the rate of obesity seen in organ transplant candidates is also rising. Accurate descriptions and measures of weight and degree of obesity vary between organ systems. Weight loss can be achieved in some patients while they wait for the transplant surgery. Weight reduction in transplant candidates involves a team approach, with a program of education and support, including medical nutrition therapy, physical therapy, and psychological support. The safety and applicability of weight loss medications to assist with pretransplant weight loss is also not well understood. It is not yet well known if weight loss before transplantation will improve posttransplant outcomes. Many questions regarding the treatment of obesity in transplant candidates remain unanswered.

Obesity paradox in advanced liver disease: obesity is associated with lower mortality in hospitalized patients with cirrhosis

BACKGROUND & AIMS

To investigate how obesity impacts inpatient mortality, length of stay (LOS) and costs in patients with cirrhosis. Obesity is a growing epidemic associated with multiple co-morbidities, increased morbidity, and a significant economic burden on healthcare. Despite the overall harmful impact of obesity, the 'obesity paradox' has been described as decreased mortality among obese vs non-obese patients in various chronic medical conditions.

METHODS

Analysis of the Nationwide Inpatient Sample (NIS) for 2012, which contains data from 44 states and 4378 hospitals. Data from all cases with primary, secondary or tertiary discharge diagnosis of cirrhosis identified by International Classification of Diseases-9 code 571.2, 571.5 571.6 were included. Primary outcomes included inpatient mortality, LOS, and hospital charges. Obesity as a predictor of mortality was defined by a predetermined obesity co-morbidity variable.

RESULTS

A total of 32,605 patients were included. Crude mortality was lower for obese cirrhotic patients (2.7% vs 3.5%, P = 0.02) than for non-obese cirrhotic patients. In contrast, median LOS was longer (4 vs 3 days, P < 0.001) and median hospital charges were higher for obese cirrhotic patients ($26 803 vs $23 447, P < 0.001) In multivariate logistic regression, obesity was associated with a lower risk of inpatient mortality (OR=0.73, 95%CI: 0.55-0.95, P = 0.02).

CONCLUSIONS

In the acute care setting, obese patients with cirrhosis have lower mortality than non-obese patients with cirrhosis, longer hospitalizations and higher healthcare cost, providing new evidence for the obesity paradox in cirrhosis. Obese cirrhotic patients are more likely to have enhanced nutritional reserve which may play a role in survival during acute illness.

Factors Affecting the Selection of Patients on Waiting List: A Single Center Study

INTRODUCTION

There is an increasing gap between organ supply and demand for cadaveric transplantation in our country. Our aim was to evaluate factors affecting selection of patients on waiting list at our hospital.

METHOD

Patients who have been waiting on list and who were transplanted were compared in order to find factors, which affected the selection of patients. Non-parametric Mann-Whitney U test was used for comparison and cox regression analysis was used to find the risk factors that decrease the probability of transplantation in this retrospective case-control study.

RESULTS

Patients in the transplanted group were significantly younger, had relatively lower body mass index than the awaiting group. Cardiovascular diseases were more in the awaiting group than the transplanted group. There was no patient with diabetes in transplanted group, despite fifteen diabetic patients were in the awaiting group. Selected patients had lower immunologic risk with regard to peak panel reactive antibody levels. No significant difference was found for gender, hypertension, hyperlipidemia, viral serology, time spent on dialysis and on waiting list between two groups. With cox regression analysis female gender, older age, diabetes mellitus, high body mass index, positive hepatitis B serology and high levels of peak class 1-2 peak panel reactive antibody positivity were found as risk factors that decrease the probability of transplantation.

CONCLUSION

A tendency for selection of low risk patients was found with this study. Time and energy consuming complications and short allograft survival after transplantation in high risk patients and the scarcity of cadaveric pool in our country may contribute to this tendency.

The associations of "fatness," "fitness," and physical activity with all-cause mortality in older adults: A systematic review

OBJECTIVE

This review explored whether cardiorespiratory fitness or physical activity act as either confounders or effect modifiers of the relationship between adiposity markers and all-cause mortality in older adults.

METHODS

Systematic searches were carried out to identify observational studies that examined the association of adiposity markers (BMI, waist circumference, and waist-hip ratio) with all-cause mortality in adults aged ≥ 60 which took into account cardiorespiratory fitness or physical activity. Data from each included study was analyzed to produce a graphical representation of this relationship.

RESULTS

Fourteen of the fifteen identified studies found that increasing BMI had a non-positive association with all-cause mortality, with persistence of the obesity paradox despite adjustment for physical activity or cardiorespiratory fitness. Physical activity measurement methods were all subjective and often unvalidated. The two studies stratifying for cardiorespiratory fitness did not find that fitness had a significant impact on the relationship between excess adiposity and mortality but found that overweight and fit people had better survival than normal-weight unfit people,

CONCLUSIONS

The predominant use of poor physical activity measurement suggests that studies are currently not adequately accounting for possible physical activity confounding. More studies are needed for addressing the modification of the relationship between adiposity markers and mortality by cardiorespiratory fitness.

Body Mass Index and Aneurysmal Subarachnoid Hemorrhage: Decreasing Mortality with Increasing Body Mass Index

BACKGROUND

Labeled the "obesity paradox," obesity has been shown to provide a survival advantage in coronary artery disease, stroke, and intracerebral hemorrhage. Studies on body mass index (BMI) in aneurysmal subarachnoid hemorrhage (SAH) show conflicting results and none examined a North American population with long-term follow-up.

METHODS

A total of 305 consecutive SAH patients (2002 to 2011) were retrospectively reviewed to collect demographics, BMI (kg/m(2)), comorbidities, Glascow Coma Scale, World Federation of Neurologic Surgeons Scale, aneurysm treatment, delayed cerebral ischemia, radiographic infarction, and short-term and long-term (> 24 months) morbidity, and mortality. Patients were stratified by BMI into category 1, < 25 kg/m(2); category 2, 25 -< 30 kg/m(2); and category 3, ≥ 30 kg/m(2).

RESULTS

Categories 1, 2, and 3 had 93, 100, and 87 patients with mean BMIs of 22.4 ± 1.8, 27.6 ± 1.4, and 35.7 ± 4.6 (P < 0.05), respectively. By category, 24-month follow-up was available in 92%, 85%, and 85%. Category 3 had more hypertension, diabetes mellitus, and clipping than category 1. Short-term mortality rates were 17%, 12%, and 8%; long-term mortality rates were 34%, 26%, and 19% (P > 0.05 at all points between categories 1 vs. 3, but not 1 vs. 2 or 2 vs. 3). On univariate analysis, BMI was inversely associated with short-term (odds ratio, 0.91; 95% confidence interval 0.84-0.98; P = 0.009) and long-term (odds ratio, 0.92; 95% confidence interval 0.87-0.97; P = 0.001) mortality. On multivariate analysis including age, World Federation of Neurologic Surgeons Scale, delayed cerebral ischemia, and radiographic infarction, BMI remained significant for short-term (odds ratio, 0.91; 95% confidence interval 0.81-0.99; P = 0.047) and long-term (odds ratio, 0.92; 95% confidence interval 0.85-0.98; P = 0.021) mortality. On Kaplan-Meier survival analysis, P > 0.05 for categories 1 versus 2 and 2 versus 3, but P = 0.005 for categories 1 versus 3.

CONCLUSIONS

In our SAH population, higher BMI resulted in less short-term and long-term mortality, but no difference in functional outcome.

The relationship of adiposity and mortality among people with diabetes in the US general population: a prospective cohort study

OBJECTIVE

Several studies have found a U-shaped association between body mass index (BMI) and mortality in the general population. In similar studies among people with diabetes, the shape of the association is inconsistent. We investigated the relationship of BMI and waist circumference with mortality among people with diabetes.

SETTING

The Third National Health and Nutrition Examination Survey (NHANES III) and the 1999-2004 NHANES Mortality Studies were designed to be representative of the US general population. Baseline data were collected in 1988-2004.

PARTICIPANTS

2607 adults ≥20 years of age with diabetes.

PRIMARY OUTCOME MEASURE

Participants were followed through 31 December 2006 for mortality (n=668 deaths).

RESULTS

Compared with people with a BMI 18.5-24.9 kg/m(2), the HRs (95% CI) of mortality were 0.85 (0.60 to 1.21) for 25-29.9 kg/m(2), 0.87 (0.57 to 1.33) for 30-34.9 kg/m(2) and 1.05 (0.72 to 1.53) for ≥35 kg/m(2) after adjustment for age, sex, race-ethnicity, smoking status, education, income and diabetes duration. Compared with people in the lowest sex-specific quartile of waist circumference, the adjusted HRs (95% CI) of mortality were 1.03 (0.77 to 1.37) for the second quartile, 1.02 (0.73 to 1.42) for the third quartile and 1.12 (0.77 to 1.61) for the highest quartile of waist circumference. When modelled as a restricted quadratic spline with knots at the 10th, 50th and 90th centiles, BMI and waist circumference were not associated with mortality. Several sensitivity analyses were conducted and most found no significant association between measures of adiposity and mortality, but there were significant results suggesting a U-shaped association among people in the highest tertile of glycated haemoglobin (≥7.1%), and there was an inverse association between BMI and mortality among people 20-44 years of age.

CONCLUSIONS

In a nationally representative sample of the non-institutionalised US population with diabetes, BMI and waist circumference were not associated with risk of mortality.

Obesity Disease and Surgery

Obesity is a medical disease that is increasing significantly nowadays. Worldwide obesity prevalence doubled since 1980. Obese patients are at great risk for complications with physical and psychological burdens, thus affecting their quality of life. Obesity is well known to have higher risk for cardiovascular diseases, diabetes mellitus, musculoskeletal diseases and shorter life expectancy. In addition, obesity has a great impact on surgical diseases, and elective surgeries in comparison to general population. There is higher risk for wound infection, longer operative time, poorer outcome, and others. The higher the BMI (body mass index), the higher the risk for these complications. This literature review illustrates the prevalence of obesity as a diseases and complications of obesity in general as well as, in a surgical point of view, general surgery perioperative risks and complications among obese patients. It will review the evidence-based updates in these headlines.

Body-mass index and mortality among adults with incident type 2 diabetes

BACKGROUND

The relation between body weight and mortality among persons with type 2 diabetes remains unresolved, with some studies suggesting decreased mortality among overweight or obese persons as compared with normal-weight persons (an "obesity paradox").

METHODS

We studied participants with incident diabetes from the Nurses' Health Study (8970 participants) and Health Professionals Follow-up Study (2457 participants) who were free of cardiovascular disease and cancer at the time of a diagnosis of diabetes. Body weight shortly before diagnosis and height were used to calculate the body-mass index (BMI, the weight in kilograms divided by the square of the height in meters). Multivariable Cox models were used to estimate the hazard ratios and 95% confidence intervals for mortality across BMI categories.

RESULTS

There were 3083 deaths during a mean period of 15.8 years of follow-up. A J-shaped association was observed across BMI categories (18.5 to 22.4, 22.5 to 24.9 [reference], 25.0 to 27.4, 27.5 to 29.9, 30.0 to 34.9, and ≥35.0) for all-cause mortality (hazard ratio, 1.29 [95% confidence interval {CI}, 1.05 to 1.59]; 1.00; 1.12 [95% CI, 0.98 to 1.29]; 1.09 [95% CI, 0.94 to 1.26]; 1.24 [95% CI, 1.08 to 1.42]; and 1.33 [95% CI, 1.14 to 1.55], respectively). This relationship was linear among participants who had never smoked (hazard ratios across BMI categories: 1.12, 1.00, 1.16, 1.21, 1.36, and 1.56, respectively) but was nonlinear among participants who had ever smoked (hazard ratios across BMI categories: 1.32, 1.00, 1.09, 1.04, 1.14, and 1.21) (P=0.04 for interaction). A direct linear trend was observed among participants younger than 65 years of age at the time of a diabetes diagnosis but not among those 65 years of age or older at the time of diagnosis (P<0.001 for interaction).

CONCLUSIONS

We observed a J-shaped association between BMI and mortality among all participants and among those who had ever smoked and a direct linear relationship among those who had never smoked. We found no evidence of lower mortality among patients with diabetes who were overweight or obese at diagnosis, as compared with their normal-weight counterparts, or of an obesity paradox. (Funded by the National Institutes of Health and the American Diabetes Association.).

No Obesity Paradox-BMI Incapable of Adequately Capturing the Relation of Obesity with All-Cause Mortality: An Inception Diabetes Cohort Study

Background. To reconcile "the obesity paradox," we tested if (1) the contribution of anthropometric measures to mortality was nonlinear and (2) the confounding of hip circumference contributed to the obesity paradox recently observed among diabetic patients. Methods. We analyzed data of diabetic patients attending a community-based prospective, "Tehran lipid and glucose study." In the mortality analysis, anthropometric measures-body mass index (BMI), waist, and hip circumference-were assessed using Cox models incorporating cubic spline functions. Results. During 12 990 person-years follow-up, BMI levels below 27 and those above 40 kg·m(-2) were associated with increased mortality. When we added waist circumference to the BMI in the multivariate-adjusted model, the steepness of BMI-mortality association curve slope for values below 27 kg·m(-2) increased, whereas the steepness of BMI-mortality association curve slope for values above this threshold decreased. Further adjusting the model for hip circumference, the steepness of the slopes of the association curve moved towards null on both extremes and no associations between BMI and all-cause mortality remained. Conclusion. BMI harbors intermixed positive and negative confounding effects on mortality of waist and hip circumference. Failing to control for the confounding effect of hip circumference may stymie unbiased hazard estimation and render conclusions paradoxical.

Association of weight status with mortality in adults with incident diabetes

CONTEXT

Type 2 diabetes in normal-weight adults (body mass index [BMI] <25) is a representation of the metabolically obese normal-weight phenotype with unknown mortality consequences.

OBJECTIVE

To test the association of weight status with mortality in adults with new-onset diabetes in order to minimize the influence of diabetes duration and voluntary weight loss on mortality.

DESIGN, SETTING, AND PARTICIPANTS

Pooled analysis of 5 longitudinal cohort studies: Atherosclerosis Risk in Communities study, 1990-2006; Cardiovascular Health Study, 1992-2008; Coronary Artery Risk Development in Young Adults, 1987-2011; Framingham Offspring Study, 1979-2007; and Multi-Ethnic Study of Atherosclerosis, 2002-2011. A total of 2625 participants with incident diabetes contributed 27,125 person-years of follow-up. Included were men and women (age >40 years) who developed incident diabetes based on fasting glucose 126 mg/dL or greater or newly initiated diabetes medication and who had concurrent measurements of BMI. Participants were classified as normal weight if their BMI was 18.5 to 24.99 or overweight/obese if BMI was 25 or greater.

MAIN OUTCOME MEASURES

Total, cardiovascular, and noncardiovascular mortality.

RESULTS

The proportion of adults who were normal weight at the time of incident diabetes ranged from 9% to 21% (overall 12%). During follow-up, 449 participants died: 178 from cardiovascular causes and 253 from noncardiovascular causes (18 were not classified). The rates of total, cardiovascular, and noncardiovascular mortality were higher in normal-weight participants (284.8, 99.8, and 198.1 per 10,000 person-years, respectively) than in overweight/obese participants (152.1, 67.8, and 87.9 per 10,000 person-years, respectively). After adjustment for demographic characteristics and blood pressure, lipid levels, waist circumference, and smoking status, hazard ratios comparing normal-weight participants with overweight/obese participants for total, cardiovascular, and noncardiovascular mortality were 2.08 (95% CI, 1.52-2.85), 1.52 (95% CI, 0.89-2.58), and 2.32 (95% CI, 1.55-3.48), respectively.

CONCLUSION

Adults who were normal weight at the time of incident diabetes had higher mortality than adults who are overweight or obese.

Adiposity facilitates increased strength capacity in heart failure patients with reduced ejection fraction

BACKGROUND

Obesity is associated with relatively improved prognosis among heart failure (HF) patients. Mechanisms explaining this so-called "obesity paradox" have been unclear. We hypothesized that increased adiposity may contribute to increased strength capacity, and may thereby facilitate clinical benefits.

METHODS AND RESULTS

In a controlled, cross-sectional study, adults aged ≥ 50 years with HF with reduced ejection fraction (HFREF) (LVEF ≤ 40%) were compared to age matched controls. Body composition was determined by dual-energy X-ray absorptiometry (DXA). Aerobic (cardiopulmonary exercise testing), maximum strength (one repetition maximum [1RM]), and power (submaximal resistance/time) were assessed. 70 adults (31 HFREF, 39 controls; mean age 66.2 ± 9.6 years) were studied. Peak oxygen consumption (VO2) (15.4 ± 4.2 vs. 23.4 ± 6.6 ml O2 · kg(-1) · min(-1), p<0.0001), 1RM (154.8 ± 52.0 vs. 195.3 ± 56.8 kg, p<0.01) and power (226.4 ± 99.2 vs. 313.3 ± 130.6, p<0.01) were lower in HFREF vs. controls. 1 RM correlated with total fat (r=0.56, p<0.01), leg fat (r=0.45, p<0.05) and arm fat (r=0.39, p<0.05) in HFREF. Moreover, among HFREF patients with a high (≥ 30 kg/m(2)) body mass index (BMI), 1RM and fat mass were significantly greater than those with lower (<30 kg/m(2)) BMIs. Correlations between 1 RM and total fat (r=0.65, p<0.05) and leg fat (r=0.64, p<0.05) were particularly notable in the high BMI subgroup.

CONCLUSION

Increased adiposity correlates with relatively greater strength in HFREF patients which may explain some of the clinical benefits that result from obesity.

Obesity and trends in life expectancy

Background. Increasing levels of obesity over recent decades have been expected to lead to an epidemic of diabetes and a subsequent reduction in life expectancy, but instead all-cause and cardiovascular-specific mortality rates have decreased steadily in most developed countries and life expectancy has increased. Methods. This paper suggests several factors that may be masking the effects of obesity on life expectancy. Results. It is possible that health and life expectancy gains could be even greater if it was not for the increasing prevalence of extreme obesity. It is also possible that the principal impact of obesity is on disability-free life expectancy rather than on life expectancy itself. Conclusion. If the principal impact of obesity were through disability-free life expectancy rather than on life expectancy itself, this would have substantial implications for the health of individuals and the future burden on the health care system.

Individual patient data meta-analysis of survival data using Poisson regression models

Background

An Individual Patient Data (IPD) meta-analysis is often considered the gold-standard for synthesising survival data from clinical trials. An IPD meta-analysis can be achieved by either a two-stage or a one-stage approach, depending on whether the trials are analysed separately or simultaneously. A range of one-stage hierarchical Cox models have been previously proposed, but these are known to be computationally intensive and are not currently available in all standard statistical software. We describe an alternative approach using Poisson based Generalised Linear Models (GLMs).

Methods

We illustrate, through application and simulation, the Poisson approach both classically and in a Bayesian framework, in two-stage and one-stage approaches. We outline the benefits of our one-stage approach through extension to modelling treatment-covariate interactions and non-proportional hazards. Ten trials of hypertension treatment, with all-cause death the outcome of interest, are used to apply and assess the approach.

Results

We show that the Poisson approach obtains almost identical estimates to the Cox model, is additionally computationally efficient and directly estimates the baseline hazard. Some downward bias is observed in classical estimates of the heterogeneity in the treatment effect, with improved performance from the Bayesian approach.

Conclusion

Our approach provides a highly flexible and computationally efficient framework, available in all standard statistical software, to the investigation of not only heterogeneity, but the presence of non-proportional hazards and treatment effect modifiers.

Body composition, symptoms, and survival in advanced cancer patients referred to a phase I service

Background

Body weight and body composition are relevant to the outcomes of cancer and antineoplastic therapy. However, their role in Phase I clinical trial patients is unknown.

Methods

We reviewed symptom burden, body composition, and survival in 104 patients with advanced cancer referred to a Phase I oncology service. Symptom burden was analyzed using the MD Anderson Symptom Assessment Inventory(MDASI); body composition was evaluated utilizing computerized tomography(CT) images. A body mass index (BMI)≥25 kg/m² was considered overweight. Sarcopenia, severe muscle depletion, was assessed using CT-based criteria.

Results

Most patients were overweight (n = 65, 63%); 53 patients were sarcopenic (51%), including 79% of patients with a BMI<25 kg/m² and 34% of those with BMI≥25 kg/m². Sarcopenic patients were older and less frequently African-American. Symptom burden did not differ among patients classified according to BMI and presence of sarcopenia. Median (95% confidence interval) survival (days) varied according to body composition: 215 (71–358) (BMI<25 kg/m²; sarcopenic), 271 (99–443) (BMI<25 kg/m²; non-sarcopenic), 484 (286–681) (BMI≥25 kg/m²; sarcopenic); 501 d (309–693) (BMI≥25 kg/m²; non-sarcopenic). Higher muscle index and gastrointestinal cancer diagnosis predicted longer survival in multivariate analysis after controlling for age, gender, performance status, and fat index.

Conclusions

Patients referred to a Phase I clinic had a high frequency of sarcopenia and a BMI≥25 kg/m², independent of symptom burden. Body composition variables were predictive of clinically relevant survival differences, which is potentially important in developing Phase I studies.

Underweight patients show an increased rate of postoperative death after surgery for hepatocellular carcinoma

OBJECTIVE

To evaluate the influence of body mass index (BMI) on postoperative death in patients undergoing surgery for HCC.

METHODS

Three hundred forty-two patients were enrolled, and divided into three groups: Group A, BMI <22.5; Group B, BMI ≥22.5 to <25; Group C, BMI ≥25. Univariate and multivariate analyses of postoperative death were performed to compare BMI with clinical factors. Kaplan-Meier analysis and log rank test were used to compare such outcome in Groups A, B, and C.

RESULTS

Kaplan-Meier analysis and log rank test revealed that Group A had a higher rate of postoperative death than Group B or C (P = 0.010). Univariate and multivariate analyses selected being underweight (Group B, C/Group A) (odds ratio, 1.829; 95% C.I., 1.091-3.068; P = 0.022) as one of the factors predictive of postoperative death, together with aspartate aminotransferase level (P = 0.042) and HCC growth pattern (P = 0.032).

CONCLUSIONS

BMI is a simple but important predictor of postoperative death in patients undergoing surgery for HCC, and is able to classify such patients into three independent groups.

The effect of obesity on health outcomes

The prevalence of obesity has progressively increased globally over the last 30 years. The determinants of this pandemic are many, poorly defined and priorities debated. While public health measures to prevent obesity have largely failed we are presented with a growing burden of disease and disability. Cardiovascular disease, type-2 diabetes, obesity related cancers, osteoarthritis and psychological disturbance generate much of the morbidity and years of life lost associated with increasing levels of obesity. Obesity has a clearly measurable impact on physical and mental health, health related quality of life, and generates considerable direct and indirect costs. The evolving obesity pandemic is exacting a considerable toll on those affected, the treating health services, and on our communities. Weight loss appears to be the most effective therapy for obesity and obesity related comorbidity. As health care researchers and providers we are likely to play a peripheral role in the prevention of obesity, but a central role in effectively treating those afflicted by the obesity pandemic.

Obesity paradox and cardiorespiratory fitness in 12,417 male veterans aged 40 to 70 years

OBJECTIVE

To evaluate the influence of cardiorespiratory fitness (fitness) on the obesity paradox in middle-aged men with known or suspected coronary artery disease.

PATIENTS AND METHODS

This study consists of 12,417 men aged 40 to 70 years (44% African American) who were referred for exercise testing at the Veterans Affairs Medical Centers in Washington, DC, or Palo Alto, CA (between January 1, 1983, and June 30, 2007). Fitness was quantified as metabolic equivalents achieved during a maximal exercise test and was categorized for analysis as low, moderate, and high (defined as <5, 5-10, and >10 metabolic equivalents, respectively). Adiposity was defined by body mass index (BMI) according to standard clinical guidelines. Separate and combined associations of fitness and adiposity with all-cause mortality were assessed by Cox proportional hazards analyses.

RESULTS

We recorded 2801 deaths during a mean+/-SD follow-up of 7.7+/-5.3 years. Multivariate hazard ratios (95% confidence interval) for all-cause mortality, with normal weight (BMI, 18.5-24.9 kg/m2) used as the reference group, were 1.9 (1.5-2.3), 0.7 (0.7-0.8), 0.7 (0.6-0.7), and 1.0 (0.8-1.1) for BMIs of less than 18.5, 25.0 to 29.9, 30.0 to 34.9, and 35.0 or more kg/m2, respectively. Compared with highly fit normal-weight men, underweight men with low fitness had the highest (4.5 [3.1-6.6]) and highly fit overweight men the lowest (0.4 [0.3-0.6]) mortality risk of any subgroup. Overweight and obese men with moderate fitness had mortality rates similar to those of the highly fit normal-weight reference group.

CONCLUSION

Fitness altered the obesity paradox. Overweight and obese men had increased longevity only if they registered high fitness.

The usefulness of the prognostic inflammatory and nutritional index (PINI) in a haemodialysis population

BACKGROUND AND AIM

Protein-Energy Wasting and inflammation are the principal risk factors of haemodialysis complications. We evaluated the reliability of a simple and non expensive test, the Prognostic Inflammatory and Nutritional Index (PINI), for regular screening of maintenance haemodialysis (MHD) patients in order to detect early onset of inflammation and malnutrition.

METHODS AND RESULTS

121 adult patients on maintenance dialysis were followed up for 32 months and screened every 6 months for PINI, calculated as alpha1-Acid Glycoprotein (alpha1-AG)xC-Reactive Protein (CRP)/AlbuminxTransthyretin. PINI score < or =1 was considered normal. Patients were stratified according to their PINI score: 86 patients (71.66%) had a normal score, whereas 35 (28.33%) had PINI > or = 1. The latter also had higher CRP levels, despite no clinical evidence of inflammation at the time of enrolment. Survival in patients with normal PINI was similar to patients with normal CRP, while in patients with abnormal PINI it was significantly lower than in patients with low serum albumin (p<0.05) or elevated CRP (p<0.05). After follow-up, all surviving MHD patients with PINI > or = 1 had at least one cardiovascular event vs 2.5% of patients with PINI > or = 1.

CONCLUSION

The assessment of PINI can reliably identify MHD patients at higher risk of mortality and morbidity even in the absence of overt Malnutrition-Inflammation Complex Syndrome (MICS). This simple test appears to be more sensitive and specific of the single components, and not expensive, so that it could be routinely used to identify patients with sub-clinical inflammation and/or malnutrition.

Cardiac remodeling in obesity

The dramatic increase in the prevalence of obesity and its strong association with cardiovascular disease have resulted in unprecedented interest in understanding the effects of obesity on the cardiovascular system. A consistent, but puzzling clinical observation is that obesity confers an increased susceptibility to the development of cardiac disease, while at the same time affording protection against subsequent mortality (termed the obesity paradox). In this review we focus on evidence available from human and animal model studies and summarize the ways in which obesity can influence structure and function of the heart. We also review current hypotheses regarding mechanisms linking obesity and various aspects of cardiac remodeling. There is currently great interest in the role of adipokines, factors secreted from adipose tissue, and their role in the numerous cardiovascular complications of obesity. Here we focus on the role of leptin and the emerging promise of adiponectin as a cardioprotective agent. The challenge of understanding the association between obesity and heart failure is complicated by the multifaceted interplay between various hemodynamic, metabolic, and other physiological factors that ultimately impact the myocardium. Furthermore, the end result of obesity-associated changes in the myocardial structure and function may vary at distinct stages in the progression of remodeling, may depend on the individual pathophysiology of heart failure, and may even remain undetected for decades before clinical manifestation. Here we summarize our current knowledge of this complex yet intriguing topic.