Effect of Body Mass Index on Outcomes of Peritoneal Dialysis Patients in India

♦ Objectives: We studied the effect of body mass index (BMI) at peritoneal dialysis (PD) initiation on patient and technique survival and on peritonitis during follow-up.♦ Methods: We followed 328 incident patients on PD (176 with diabetes; 242 men; mean age: 52.6 ± 12.6 years; mean BMI: 21.9 ± 3.8 kg/m²) for 20.0 ± 14.3 months. Patients were categorized into four BMI groups: obese, ≥25 kg/m²; overweight, 23 - 24.9 kg/m²; normal, 18.5 - 22.9 kg/m² (reference category); and underweight, <18.5 kg/m². The outcomes of interest were compared between the groups.♦ Results: Of the 328 patients, 47 (14.3%) were underweight, 171 (52.1%) were normal weight, 53 (16.2%) were overweight, and 57 (17.4%) were obese at commencement of PD therapy. The crude hazard ratio (HR) for mortality (p = 0.004) and the HR adjusted for age, subjective global assessment, comorbidities, albumin, diabetes, and residual glomerular filtration rate (p = 0.02) were both significantly greater in the underweight group than in the normal-weight group. In comparison with the reference category, the HR for mortality was significantly greater for underweight PD patients with diabetes [2.7; 95% confidence interval (CI): 1.5 to 5.0; p = 0.002], but similar for all BMI categories of nondiabetic PD patients.Median patient survival was statistically inferior in underweight patients than in patients having a normal BMI. Median patient survival in underweight, normal, overweight, and obese patients was, respectively, 26 patient-months (95% CI: 20.9 to 31.0 patient-months), 50 patient-months (95% CI: 33.6 to 66.4 patient-months), 57.7 patient-months (95% CI: 33.2 to 82.2 patient-months), and 49 patient-months (95% CI: 18.4 to 79.6 patient-months; p = 0.015). Death-censored technique survival was statistically similar in all BMI categories. In comparison with the reference category, the odds ratio for peritonitis occurrence was 1.8 (95% CI: 0.9 to 3.4; p = 0.086) for underweight patients; 1.7 (95% CI: 0.9 to 3.2; p = 0.091) for overweight patients; and 3.4 (95% CI: 1.8 to 6.4; p < 0.001) for obese patients.♦ Conclusions: In our PD patients, mean BMI was within the normal range. The HR for mortality was significantly greater for underweight diabetic PD patients than for patients in the reference category. Death-censored technique survival was similar in all BMI categories. Obese patients had a greater risk of peritonitis.     

Weekend compared with weekday presentations of peritoneal dialysis-associated peritonitis

♦ Objective: Management of peritoneal dialysis (PD)-associated peritonitis requires timely intervention by experienced staff, which may not be uniformly available throughout the week. The aim of the present study was to examine the effects of weekend compared with weekday presentation on peritonitis outcomes.♦ Methods: The study, which used data from the Australia and New Zealand Dialysis and Transplant Registry, included all Australian patients receiving PD between 1 October 2003 and 31 December 2008. The independent predictors of weekend presentation and subsequent peritonitis outcomes were assessed by multivariate logistic regression.♦ Results: Peritonitis presentation rates were significantly lower on Saturdays [0.46 episodes per year; 95% confidence interval (CI): 0.42 to 0.49 episodes per year] and on Sundays (0.43 episodes per year; 95% CI: 0.40 to 0.47 episodes per year) than all other weekdays; they peaked on Mondays (0.76 episodes per year; 95% CI: 0.72 to 0.81 episodes per year). Weekend presentation with a first episode of peritonitis was independently associated with lower body mass index and residence less than 100 km away from the nearest PD unit. Patients presenting with peritonitis on the weekend were significantly more likely to be hospitalized [adjusted odds ratio (OR): 2.32; 95% CI: 1.85 to 2.90], although microbial profiles and empiric antimicrobial treatments were comparable between the weekend and weekday groups. Antimicrobial cure rates were also comparable (79% vs 79%, p = 0.9), with the exception of cure rates for culture-negative peritonitis, which were lower on the weekend (80% vs 88%, p = 0.047). Antifungal prophylaxis was less likely to be co-prescribed for first peritonitis episodes presenting on weekdays (OR: 0.68; 95% CI: 0.05 to 0.89).♦ Conclusions: Patients on PD are less likely to present with peritonitis on the weekend. Nevertheless, the microbiology, treatment, and outcomes of weekend and weekday PD peritonitis presentations are remarkably similar. Exceptions include the associations of weekend presentation with a higher hospitalization rate and a lower cure rate in culture-negative infection.     

Relationship of Body Mass Index With Total Mortality,Cardiovascular Mortality,and Myocardial Infarction After Coronary Revascularization: Evidence From a Meta-analysis

ObjectiveTo investigate the relationship of body mass index (BMI) with total mortality, cardiovascular (CV) mortality, and myocardial infarction (MI) after coronary revascularization procedures (coronary artery bypass grafting [CABG] and percutaneous coronary intervention [PCI]).Patients and MethodsSystematic search of studies was conducted using PubMed, CINAHL, Cochran CENTRAL, Scopus, and the Web of Science databases. We identified studies reporting the rate of MI, CV mortality, and total mortality among coronary artery disease patients' postcoronary revascularization procedures in various BMI categories: less than 20 (underweight), 20-24.9 (normal reference), 25-29.9 (overweight), 30-34.9 (obese), and 35 or more (severely obese). Event rates were compared using a random effects model assuming interstudy heterogeneity.ResultsA total of 36 studies (12 CABG; 26 PCI) were selected for final analyses. The risk of total mortality (relative risk [RR], 2.59; 95% CI, 2.09-3.21), CV mortality (RR, 2.67; 95% CI, 1.63-4.39), and MI (RR, 1.79; 95% CI, 1.28-2.50) was highest among patients with low BMI at the end of a mean follow-up period of 1.7 years. The risk of CV mortality was lowest among overweight patients (RR, 0.81; 95% CI, 0.68-0.95). Increasing degree of adiposity as assessed by BMI had a neutral effect on the risk of MI for overweight (RR, 0.92; 95% CI, 0.84-1.01), obese (RR, 0.99; 95% CI, 0.85-1.15), and severely obese (RR, 0.93; 95% CI, 0.78-1.11) patients.ConclusionAfter coronary artery disease revascularization procedures (PCI and CABG), the risk of total mortality, CV mortality, and MI was highest among underweight patients as defined by low BMI and CV mortality was lowest among overweight patients.     

Body mass index is independently associated with hospital mortality in mechanically ventilated adults with acute lung injury

OBJECTIVE: To determine the association between body mass index (BMI) and hospital mortality for critically ill adults. DESIGN: Retrospective cohort study. SETTING: One-hundred six intensive care units (ICUs) in 84 hospitals. PATIENTS: Mechanically ventilated adults (n=1,488) with acute lung injury (ALI) included in the Project IMPACT database between December 1995 and September 2001. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Over half of the cohort had a BMI above the normal range. Unadjusted analyses showed that BMI was higher among subjects who survived to hospital discharge vs. those who did not (p<.0001). ICU and hospital mortality rates were lower in higher BMI categories. After risk-adjustment, BMI was independently associated with hospital mortality (p<.0001) when modeled as a continuous variable. The adjusted odds were highest at the lowest BMIs and then declined to a minimum between 35 and 40 kg/m2. Odds increased after the nadir but remained below those seen at low BMIs. With use of a categorical designation, BMI was also independently associated with hospital mortality (p=.0055). The adjusted odds were highest for the underweight BMI group (adjusted odds ratio [OR], 1.94; 95% confidence interval [CI], 1.05-3.60) relative to the normal BMI group. As in the analysis using the continuous BMI variable, the odds of hospital mortality were decreased for the groups with higher BMIs (overweight adjusted OR, 0.72; 95% CI, 0.51-1.02; obese adjusted OR, 0.67; 95% CI, 0.46-0.97; severely obese adjusted OR, 0.78; 95% CI, 0.44-1.38). Differences in the use of heparin prophylaxis mediated some of the protective effect of severe obesity. CONCLUSIONS: BMI was associated with risk-adjusted hospital mortality among mechanically ventilated adults with ALI. Lower BMIs were associated with higher odds of death, whereas overweight and obese BMIs were associated with lower odds.     

The Effect of Exit-Site Antibacterial Honey Versus Nasal Mupirocin Prophylaxis on the Microbiology and Outcomes of Peritoneal Dialysis-Associated Peritonitis and Exit-Site Infections: A Sub-Study of the Honeypot Trial

♦ Background:

The HONEYPOT study recently reported that daily exit-site application of antibacterial honey was not superior to nasal mupirocin prophylaxis for preventing overall peritoneal dialysis (PD)-related infection. This paper reports a secondary outcome analysis of the HONEYPOT study with respect to exit-site infection (ESI) and peritonitis microbiology, infectious hospitalization and technique failure.

♦ Methods:

A total of 371 PD patients were randomized to daily exit-site application of antibacterial honey plus usual exit-site care (N = 186) or intranasal mupirocin prophylaxis (in nasal Staphylococcus aureus carriers only) plus usual exit-site care (control, N = 185). Groups were compared on rates of organism-specific ESI and peritonitis, peritonitis- and infection-associated hospitalization, and technique failure (PD withdrawal).

♦ Results:

The mean peritonitis rates in the honey and control groups were 0.41 (95% confidence interval [CI] 0.32 – 0.50) and 0.41 (95% CI 0.33 – 0.49) episodes per patient-year, respectively (incidence rate ratio [IRR] 1.01, 95% CI 0.75 – 1.35). When specific causative organisms were examined, no differences were observed between the groups for gram-positive (IRR 0.99, 95% CI 0.66 – 1.49), gram-negative (IRR 0.71, 95% CI 0.39 – 1.29), culture-negative (IRR 2.01, 95% CI 0.91 – 4.42), or polymicrobial peritonitis (IRR 1.08, 95% CI 0.36 – 3.20). Exit-site infection rates were 0.37 (95% CI 0.28 – 0.45) and 0.33 (95% CI 0.26 – 0.40) episodes per patient-year for the honey and control groups, respectively (IRR 1.12, 95% CI 0.81 – 1.53). No significant differences were observed between the groups for gram-positive (IRR 1.10, 95% CI 0.70 – 1.72), gram-negative (IRR: 0.85, 95% CI 0.46 – 1.58), culture-negative (IRR 1.88, 95% CI 0.67 – 5.29), or polymicrobial ESI (IRR 1.00, 95% CI 0.40 – 2.54). Times to first peritonitis-associated and first infection-associated hospitalization were similar in the honey and control groups. The rates of technique failure (PD withdrawal) due to PD-related infection were not significantly different between the groups.

♦ Conclusion:

Compared with standard nasal mupirocin prophylaxis, daily topical exit-site application of antibacterial honey resulted in comparable rates of organism-specific peritonitis and ESI, infection-associated hospitalization, and infection-associated technique failure in PD patients.     

Is obesity a favorable prognostic factor in peritoneal dialysis patients?

OBJECTIVE: To determine the influence of an elevated body mass index (BMI) on cardiovascular outcomes and survival in peritoneal dialysis (PD) patients. DESIGN: Prospective, observational study of a prevalent PD cohort at a single center. SETTING: Tertiary care institutional dialysis center. PATIENTS: The study included all patients with a BMI of at least 20 who had been receiving PD for at least 1 month as of 31 January 1996 (n = 43). Patients were classified as overweight [BMI > 27.5; mean +/- standard error of mean (SEM): 32.1 +/- 1.1; n = 14] or normal weight (BMI 20-27.5; mean +/- SEM: 23.8 +/- 0.4; n = 29). OUTCOME MEASURES: Patient survival and adverse cardiovascular events (myocardial infarction, congestive cardiac failure, cerebrovascular accident, and symptomatic peripheral vascular disease) were recorded over a 3-year period. RESULTS: At baseline, no significant differences were seen between the groups in clinical, biochemical, nutritional, or echocardiographic parameters, except for a lower dietary protein intake (0.97 +/- 0.10 g/kg/day vs 1.44 +/- 0.10 g/kg/day, p = 0.004) and a higher proportion of well-nourished patients by subjective global assessment (100% vs 72%, p < 0.05) in the overweight group. After 3 years of follow-up, 29% of overweight patients and 69% of normal-weight patients had died (p < 0.05). Using a Cox proportional hazards model, a BMI greater than 27.5 was shown to be an independent positive predictor of patient survival, with an adjusted hazard ratio (HR) of 0.09 [95% confidence interval (CI): 0.01-0.85; p < 0.05]. However, being overweight did not significantly influence myocardial infarction-free survival (adjusted HR: 0.33; 95% CI: 0.07-1.48; p = 0.15) or combined adverse cardiovascular event-free survival (adjusted HR: 0.67; 95% CI: 0.23-1.93; p = 0.46). CONCLUSIONS: Obesity conferred a significant survival advantage in our PD population. Obese patients should therefore not be discouraged from receiving PD purely on the basis of BMI. Moreover, maintaining a higher-than-average BMI to preserve "nutritional reserve" may help to reduce the mortality and morbidity rates associated with PD.     

The role of body mass index in the development of thromboembolic events among cancer patients with PICCs: a systematic review

ObjectivePeripherally inserted central catheters (PICC) guarantee a stable and safe vascular access to administer irritants or vesicants therapies. However, they may occasionally be affected by relevant thrombotic complications especially in patients with hypercoagulability such as oncological patients. Among the identification of independent risk factors, the role of body mass index (BMI) ≥25 kg/m² is now emerging in literature with conflicting results. The aim of this systematic review is to analyze the available scientific literature in order to determine whether BMI could represent a risk factor in the development of thromboembolic event among cancer patients with PICCs.Data sources and review methodsA scientific literature review was performed in Pubmed, Embase and Cinahl from Jan 1, 2010 to September 10, 2020 in which we identified 100 records. Of these, 88 were excluded and 14 were reviewed in full text. Among the reviewed records, 6 articles satisfied the inclusion criteria for analysis. These criteria included the English language, oncological patients with PICCs, the evaluation of catheter-related thrombosis as well as the stratification of patients according to BMI. Studies off topic and lacking data on PICC related complications among overweight and underweight patients were excluded. The includedstudies, judged with Newcastle-Ottawa Scale, was fair-lower quality. The primary endpoint was the relative risk (RR) of PICC-related thrombosis of overweight/obese vs normal weight/underweight (i.e., BMI ≥25 vs <25 kg/m²) in cancer patients.ResultsA total of 2431 patients were included in the analysis. Overall, 15.1% of patients developed PICC-related thrombosis within a median time of 23.2 days (range 11.0-42.5) after PICC implantation. Concerning BMI, 52.6% of the entire population was overweight/obese. We assessed the proportion of patients with PICC-related thrombotic events in the two groups, with 28% (95% CI, 12%-45%) of events registered in the overweight/obese patients cohort, and 13% (95% CI, 6%-19%) in the normal weight/underweight cohort. The pooled relative risk (RR) was 2.06 (95% CI, 1.21-3.49, p<0.001) in overweight/obese vs normal weight/underweight patients.ConclusionThis review showed a two-fold risk of thrombosis in overweight/obese compared to normal weight/underweight oncological patients with PICCs. Underweight condition could also play a role in thrombosis development, especially in nasopharyngeal and digestive system cancer. Future prospective studies are needed to achieve reliable results and produce useful conclusion.     

Effects of Climatic Region on Peritonitis Risk,Microbiology, Treatment,and Outcomes: a Multicenter Registry Study

♦ Background: The impact of climatic variations on peritoneal dialysis (PD)-related peritonitis has not been studied in detail. The aim of the current study was to determine whether various climatic zones influenced the probability of occurrence or the clinical outcomes of peritonitis.♦ Methods: Using ANZDATA registry data, the study in cluded all Australian patients receiving PD between 1 October 2003 and 31 December 2008. Climatic regions were defined according to the Köppen classification.♦ Results: The overall peritonitis rate was 0.59 episodes per patient-year. Most of the patients lived in Temperate regions (65%), with others residing in Subtropical (26%), Tropical (6%), and Other climatic regions (Desert, 0.6%; Grassland, 2.3%). Compared with patients in Temperate regions, those in Tropical regions demonstrated significantly higher overall peritonitis rates and a shorter time to a first peritonitis episode [adjusted hazard ratio: 1.15; 95% confidence interval (CI): 1.01 to 1.31]. Culture-negative peritonitis was significantly less likely in Tropical regions [adjusted odds ratio (OR): 0.42; 95% CI: 0.25 to 0.73]; its occurrence in Subtropical and Other regions was comparable to that in Temperate regions. Fungal peritonitis was independently associated with Tropical regions (OR: 2.18; 95% CI: 1.22 to 3.90) and Other regions (OR: 3.46; 95% CI: 1.73 to 6.91), where rates of antifungal prophylaxis were also lower. Outcomes after first peritonitis episodes were comparable in all groups.♦ Conclusions: Tropical regions were associated with a higher overall peritonitis rate (including fungal peritonitis) and a shorter time to a first peritonitis episode. Augmented peritonitis prophylactic measures such as antifungal therapy and exit-site care should be considered in PD patients residing in Tropical climates.Key words: Antibiotics, bacteria, climate, fungus, microbiology, peritonitis, outcomesPeritonitis is a serious complication of peritoneal dialysis (PD), responsible for significant morbidity and accounting for 30% of technique failures and 21% of infectious deaths in Australian and New Zealand PD patients (1). Studies of organism-specific peritonitis (2-12) have not previously assessed the role of climatic variation in peritonitis and in its microbiologic causes. The temperature and humidity differences in individual climatic regions may influence the development of PD peritonitis by changing patient behavior and hygiene, distribution of normal skin flora, organism virulence, and the chance of contamination.Previous studies attempting to demonstrate a relationship between changes in temperature and humidity and the occurrence of PD peritonitis have had conflicting outcomes (13-17). Those studies have been limited by small patient numbers, single-center sourcing, retrospective design, and sometimes inappropriate statistical analysis and a relatively narrow range of temperatures and humidity in the studied regions, which were often within one climatic region, thereby possibly underestimating the true effect of climatic variation. To date, no comprehensive, multicenter examination of the impact of climate on PD peritonitis has been reported.Australia is in a unique position to evaluate the climate question because it encompasses a range of different climatic regions. The aim of the present study was therefore to examine the effect of climatic regional variation on the risk, microbiology, treatment, and clinical outcomes of PD-associated peritonitis in all Australian PD patients, as recorded in the ANZDATA registry.     

The effect of body weight on CAPD related infections and catheter loss

CAPD related infections and catheter loss continue to be the major problems facing the peritoneal dialysis patient. Few risk factors for infections and catheter loss have been identified. We hypothesized that overweight and underweight patients may be at increased risk for infections and catheter related problems. We examined the effect of the patient's weight at the start of peritoneal dialysis on the subsequent peritonitis and catheter infection rates, as well as catheter loss. Weight was expressed as a percentage of ideal body weight (IBW). Those patients who were more than 110% of IBW were considered to be overweight, 90 to 110% of IBW normal and less than 90%, underweight. An equivalent percentage of patients were overweight and underweight at the initiation of peritoneal dialysis (55/228, 24% for both groups). Overweight, normal, and underweight patients had peritonitis rates of 1.0, 0.9, and 0.8 episodes/y and catheter infection rates of 1.1, 1.2, and 0.8 episodes/y, respectively. Despite these similar rates, catheter loss due to infectious complications was greatest in the overweight group and least in the underweight group (p less than 0.05). No obvious explanation for the difference in catheter loss rate was found. Neither S. aureus nor P. aeruginosa infections occurred more frequently in the overweight patients. However, S. aureus infections more often led to catheter loss in the overweight patients. Catheter loss due to catheter leaks and failure to drain was similar in the three groups of patients. We conclude that deviation from ideal body weight at the initiation of dialysis is not a risk factor for CAPD related infections.(ABSTRACT TRUNCATED AT 250 WORDS)     

Overweight is associated with improved survival and outcomes in patients with atrial fibrillation

Background

The aim of this study was to investigate the association of body mass index (BMI) with mortality and cardiovascular events in Chinese patients with atrial fibrillation (AF).

Methods and results

This study consecutively enrolled AF patients presenting to an emergency department at 20 hospitals in China from November 2008 to October 2011. A total of 2,016 AF patients was enrolled, and patients were categorized as underweight (BMI <18.5), normal (BMI 18.5 to <24), overweight (BMI 24 to <28), and obese (BMI ≥28 all kg/m²). Multivariate Cox proportional hazards regression was used on all the patients. End points of the analyses were all-cause mortality, cardiovascular mortality, and combined end events. Among overall patients, mean BMI was 23.5 ± 3.6 kg/m²; 279 (13.8 %) patients died during 12-month follow-up, and so did 23.2 % underweight, 16.3, 9.5 and 9.2 % normal weight, overweight, and obese patients, respectively (P < 0.001). Cardiovascular mortality was 8.3% in all patients, and in underweight, normal weight, overweight and obese categories were 16.5, 9.0, 5.4 and 6.9 %, respectively (P < 0.001). On multivariate analysis, as continuous variable, BMI was not a risk factor for all-cause mortality in AF patients (hazard ratio [HR] 0.94; 95 % confidence interval [CI] 0.91–0.97; P = 0.001). As categorical variable, underweight (HR 1.57, 95 % CI 1.02–2.42, P = 0.041) and normal weight (HR 1.53, 95 % CI 1.13–2.06, P = 0.005) categories were associated with higher all-cause mortality as compared with overweight category. Underweight (HR 2.01, 95 % CI 1.76–3.43, P = 0.011) and normal weight patients (HR 1.53, 95 % CI 1.03–2.28, P = 0.037) also had higher cardiovascular mortality as compared with the overweight category.

Conclusions

Obesity and overweight were not risk factors for 12-month mortality in Chinese AF patients. Overweight AF patients have better survival and outcomes than normal weight (BMI 18.5–24 kg/m²) and underweight patients.     

Methodological issues in assessing the incidence of peritoneal dialysis-associated peritonitis in children.

OBJECTIVES: To evaluate the distribution of peritonitis incidence and assess the usefulness of patient-specific peritonitis rates in children. DESIGN: 49 children on automated peritoneal dialysis (PD) followed during a 2-year observation period. SETTING: Single-center, academic children's hospital. PATIENTS: 49 children aged 2 months to 18 years; 24 prevalent, 25 incident during the observation period. Cumulative observation time was 639 patient-months. MAIN OUTCOME MEASURES: Cohort-specific peritonitis incidence, median patient-specific peritonitis incidence, mean peritonitis incidence by gamma-Poisson (negative binomial) modeling, peritonitis-free survival by Kaplan-Meier life-table analysis. RESULTS: 68 new peritonitis episodes and 21 relapses occurred in 27 patients.The distribution of patient-specific peritonitis incidence was bimodal, with a large group experiencing no or very few episodes, and another cluster around 1 episode per 6-9 months. Overall cohort-specific peritonitis incidence was 1.28, median subject-specific incidence 0.99, and mean incidence according to negative binomial modeling 1.04 (95% confidence interval 1.02-1.06) episodes per patient-year. Median peritonitis-free survival time was 6.9 months. In those patients who developed peritonitis, subject-specific peritonitis incidence was inversely correlated with patient age (r = -0.42, p < 0.05) and duration of chronic PD at last observation (r = -0.42, p < 0.05). CONCLUSIONS: Since the distribution of peritonitis in children is non-Gaussian, the average risk of peritonitis is more accurately expressed by the median of the individual subject-specific peritonitis rates or by the mean incidence estimate obtained by the negative binomial distribution model. The assignment of a personal peritonitis risk to each patient permits risk factor analysis by routine statistical methods, even in smaller populations.     

A quarter of a century of adult peritoneal dialysis-related peritonitis at an Australian medical center.

BACKGROUND: Peritonitis remains one of the major complications of peritoneal dialysis (PD) and results in reduced technique survival and increased patient morbidity and mortality. METHODS: We prospectively recorded comprehensive data on all episodes of PD peritonitis over a 25-year period, including organisms isolated and antibiotic sensitivities. Data on 1588 PD patient-years with 2073 episodes of peritonitis were analyzed; 2089 organisms were isolated in 608 patients. Peritoneal dialysis technique and patient survival were also recorded. RESULTS: There was a significant decline over the years in the incidence of peritonitis, from 6.5 to 0.35 episodes/patient-year, with the decline in the post twin-bag era from 2.3 to 0.47 (p < 0.001) due primarily to a decrease in gram-positive organisms. The most common isolates (68.9%) were gram-positive organisms; gram-negative organisms comprised 26.8% and fungi 4.1%. Coagulase-negative staphylococci were the most common pathogen isolated (35.3%). Culture-negative peritonitis was seen in 13.4% of episodes. CONCLUSION: This is the largest series of PD peritonitis reported, demonstrating a dramatic reduction over a 25-year period and also detailing the changing trends of organisms isolated in association with improved technique and patient survival. Although rates have improved, peritonitis remains a major complication and further research needs to be done to improve both PD technique and patient survival.     

Effect of body size and body composition on survival in peritoneal dialysis patients.

BACKGROUND: Using 24-hour urinary creatinine excretion as a measure of muscle mass, we examined whether body composition influences the survival of incident peritoneal dialysis (PD) patients. We hypothesized that patients with high body mass index (BMI) and low muscle mass might be considered to have high levels of body fat. METHODS: Using serum creatinines and creatinine clearances reported on Medical Evidence Form 2728, 24-hour urinary creatinine was calculated in 10 140 incident PD patients with normal (18.5 - 24.9 kg/m2) or high (> or = 25 kg/m2) BMI. Patients were classified as low and normal/high muscle mass groups based on the 25th percentile of 24-hour urinary creatinine (0.64 g/day). RESULTS: In multivariable parametric survival models, compared to the normal BMI-normal/high muscle mass patients, high BMI-normal/high muscle mass patients had lower hazard of all-cause [hazard ratio (HR) 0.90, 95% confidence interval (CI) 0.83 - 0.97] and cardiovascular (HR 0.88, 95% CI 0.79 - 0.97) death; high BMI patients with low muscle mass had higher hazard of all-cause (HR 1.29, 95% CI 1.17 - 1.42) and cardiovascular (HR 1.21, 95% CI 1.06 - 1.39) death. CONCLUSION: Both body size and body composition influence survival of incident PD patients. As incident PD patients with high BMI and normal or high muscle mass have the best survival, PD patients should be encouraged to gain muscle mass rather than fat mass.     

Healthy body mass index values often underestimate body fat in men with spinal cord injury

OBJECTIVE: To examine the relation between body mass index (BMI) and adiposity in men with spinal cord injury (SCI). DESIGN: Cross-sectional study. SETTING: Outpatient study in 2 centers in New Zealand. PARTICIPANTS: Nineteen men with traumatic SCI were age-, height-, and weight-matched with 19 able-bodied men. INTERVENTIONS: Not applicable.Main Outcome Measures: BMI (kg/m(2)) and dual-energy x-ray absorptiometry measures of total and regional lean tissue mass and fat mass. RESULTS: Although the groups had similar BMIs, the total lean tissue mass was 8.9kg lower (95% confidence interval [CI], -12.7 to -5.2; P<.001) whereas total fat mass was 7.1kg greater (95% CI, 1.3-12.8; P<.05) in the SCI group. Body fat percentage was 9.4% (95% CI, 3.6-15.1; P<.01) greater in the SCI group. Regional measures showed a similar pattern. Truncal fat mass increased 3.7kg (95% CI, 0.5-6.9; P<.05) in the SCI group compared with controls. CONCLUSIONS: Body fat mass was greater for any given BMI in the SCI group. Many patients with SCI do not appear to be obese, yet they carry large amounts of fat tissue. BMI is widely used to estimate adiposity, but it may underestimate body fat in men with SCI.     

Predictors of Peritonitis,Hospital Days,and Technique Survival for Peritoneal Dialysis Patients in a Managed Care Setting

♦ Introduction: Many clinicians perceive that peritoneal dialysis (PD) should be reserved for younger, healthier, more affluent patients. Our aim was to examine outcomes for PD patients in a managed care setting and to identify predictors of adverse outcomes.♦ Methods: We identified all patients who initiated PD at our institution between 1 January 2001 and 31 December 2010. Predictor variables studied included age, sex, race, PD modality, cause of end-stage renal disease (ESRD), dialysis vintage, Charlson comorbidity index (CCI) score, education, and income level. Poisson models were used to determine the relative risk (RR) of peritonitis and the number of hospital days per patient-year. The log-rank test was used to compare technique survival by patient strata.♦ Results: Among the 1378 patients who met the inclusion criteria, only female sex [RR: 0.85; 95% confidence interval (CI): 0.74 to 0.98; p = 0.02] and higher education (RR: 0.77; 95% CI: 0.60 to 0.98; p = 0.04) were associated with peritonitis. For hospital days, dialysis vintage (RR: 1.11; 95% CI: 1.04 to 1.18; p = 0.002), CCI score (RR: 1.06; 95% CI: 1.02 to 1.20; p = 0.002), and cause of ESRD (RR for glomerulonephritis: 0.59; 95% CI: 0.43 to 0.80; p = 0.0006; and RR for hypertension: 0.69; 95% CI: 0.55 to 0.88; p = 0.002) were associated with 1 extra hospital day per patient-year. The 2-year technique survival was 61% for patients who experienced at least 1 episode of peritonitis and 72% for those experiencing no peritonitis (p = 0.0001). Baseline patient age, primary cause of ESRD, and PD modality were the only other variables associated with technique survival in the study.♦ Conclusions: Neither race nor socio-economic status predicted technique survival or hospital days in our study. Female sex and higher education were the only two variables studied that had an association with peritonitis.     

Body mass index and mortality in patients with acute venous thromboembolism: findings from the RIETE registry

Summary.  Background:  There is little information on the influence of body mass index (BMI) on mortality in patients with acute venous thromboembolism (VTE). Patients and methods:  RIETE is an ongoing registry of consecutive patients with symptomatic, objectively confirmed, acute VTE. We examined the association between BMI and mortality during the first 3 months of therapy. Results:  Of the 10 114 patients enrolled as of March 2007: 153 (1.5%) were underweight (BMI < 18.5); 2882 (28%) had a normal weight (BMI 18.5–24.9); 4327 (43%) were overweight (BMI 25.0–30); and 2752 (27%) were obese (BMI > 30). The overweight and obese patients were significantly older, and were less likely to have had cancer, recent immobility or renal insufficiency. After 3 months of therapy their death rates were 28%, 12%, 6.2% and 4.2%, respectively. In multivariate analysis, the relative risks for death after adjusting for confounding variables including age, cancer, renal insufficiency or idiopathic VTE were: 2.1 (95% CI, 1.5–2.7); 1.0 (reference); 0.6 (95% CI, 0.5–0.7); and 0.5 (95% CI, 0.4–0.6), respectively. The rates of fatal pulmonary embolism (2.0%, 2.1%, 1.2% and 0.8%, respectively) also decreased with BMI. There were no differences in the rate of fatal bleeding, but patients who were underweight had an increased incidence of major bleeding complications (7.2% vs. 2.7%; odds ratio, 2.7; 95% CI, 1.4–5.1). Conclusions:  Obese patients with acute VTE have less than half the mortality rate when compared with normal BMI patients. This reduction in mortality rates was consistent among all subgroups and persisted after multivariate adjustment.     

Obesity, inactivity, and the prevalence of diabetes and diabetes-related cardiovascular comorbidities in the U.S., 2000-2002

OBJECTIVE: Obesity and physical inactivity are established risk factors for type 2 diabetes and cardiovascular comorbidities. Whether adiposity or fitness level is more important to health is controversial. The objective of this research is to determine the relative associations of physical activity and BMI with the prevalence of diabetes and diabetes-related cardiovascular comorbidities in the U.S. RESEARCH DESIGN AND METHODS: The Medical Expenditure Panel Survey (MEPS) is a nationally representative survey of the U.S. population. From 2000 to 2002, detailed information on sociodemographic characteristics and health conditions were collected for 68,500 adults. Normal weight was defined as BMI 18.5 to <25 kg/m(2), overweight 25 to < or =30 kg/m(2), obese (class I and II) 30 to <40 kg/m(2), and obese (class III) > or =40 kg/m(2). Physical activity was defined as moderate/vigorous activity > or =30 min > or =3 days per week. RESULTS: The likelihood of having diabetes and diabetes-related cardiovascular comorbidities increased with BMI regardless of physical activity and increased with physical inactivity regardless of BMI. Compared with normal-weight active adults, the multivariate-adjusted odds ratio (OR) for diabetes was 1.52 (95% CI 1.25-1.86) for normal-weight inactive adults and 1.65 (1.40-1.96) for overweight inactive adults; the OR for diabetes and comorbid hypertension was 1.71 (1.32-2.19) for normal-weight inactive adults and 1.84 (1.47-2.32) for overweight inactive adults. CONCLUSIONS: Both physical inactivity and obesity seem to be strongly and independently associated with diabetes and diabetes-related comorbidities. These results support continued research investigating the independent causal nature of these factors.     

Frequency and Microbiology of Peritonitis and Exit-Site Infection Among Obese Peritoneal Dialysis Patients

♦ Background: Data on obesity as a risk factor for peritonitis and catheter infections among peritoneal dialysis (PD) patients are limited. Furthermore, little is known about the microbiology of PD-related infections among patients with a high body mass index (BMI).♦ Methods: Using a cohort that included all adult patients residing in the province of Manitoba who received PD during the period 1997 - 2007, we studied the relationship between BMI and PD-related infections. After categorizing patients into quartiles of BMI, a multivariate Cox regression model was used to determine the independent relationship between BMI and peritonitis or exit-site infection (ESI). We also studied whether increasing BMI was associated with a propensity to infections with particular organisms.♦ Results: Among 990 PD patients, 938 (95%) had accurate BMI data available. Those 938 patients experienced 1338 peritonitis episodes and 1194 exit-site infections. In unadjusted analyses, patients in the highest BMI quartile (median: 33.5; interquartile range: 31.9 - 36.4) had an increased risk of peritonitis overall, and also an increased risk of peritonitis with gram-positive organisms and coagulase-negative Staphylococcus (CNS). After multivariate adjustment for age, sex, diabetes, cause of renal disease, Aboriginal race, PD modality, and S. aureus nasal carriage, the relationship between overall peritonitis risk and BMI disappeared, but the increased risk of CNS peritonitis among patients in the highest BMI quartile persisted (hazard ratio: 1.80; 95% confidence interval: 1.06 to 3.06; p = 0.03). There was no increased risk of ESI among patients in the highest BMI quartile on univariate analysis or after multivariate adjustment.♦ Conclusions: Among Canadian PD patients, obesity was not associated with an increased risk of peritonitis overall, but may be associated with a higher risk of CNS peritonitis.Key words: Body mass index, exit-site infection, obesity, peritonitisBody mass index (BMI) is frequently taken into account when selecting a dialysis modality. One concern with regard to peritoneal dialysis (PD) is the possibility that obesity may increase the risk of mechanical complications such as leaks and hernias because of increased intra-abdominal pressure (1). An additional concern is the impact of obesity on PD-related infectious complications—a subject about which data are limited.The two largest observational studies to have assessed the relationship between BMI and PD peritonitis both come from ANZDATA, the Australian and New Zealand Dialysis and Transplant Registry (2,3). In those studies, obesity was associated with an increased risk of peritonitis, with one study reporting a hazard ratio (HR) of 1.08 per 5 kg/m² increase in BMI (3), and the other reporting a HR of 1.29 in patients with a BMI of 30 or more (2). The microbiology of peritonitis was not reported in those studies.Using a large cohort of Canadian PD patients, our primary objective was to study the relationship between obesity and PD-related infection, including peritonitis and exit-site infection (ESI). Our secondary objective was to determine whether high BMI among PD patients is associated with a propensity for infection with particular organisms.     

Being overweight or obese is associated with decreased mortality in critically ill patients: A retrospective analysis of a large regional Italian multicenter cohort

Purpose

To describe the epidemiology of obesity in a large cohort of intensive care unit (ICU) patients and study its impact on outcomes.

Methods

All 3902 patients admitted to one of 24 ICUs in the Piedmont region of Italy from April 3 to September 29, 2006, were included in this retrospective analysis of data from a prospective, multicenter study.

Results

Mean body mass index (BMI) was 26.0 ± 5.4 kg/m²: 32.8% of patients had a normal BMI, 2.6% were underweight, 45.1% overweight, 16.5% obese, and 2.9% morbidly obese. ICU mortality was significantly (P < .05) lower in overweight (18.8%) and obese (17.5%) patients than in those of normal BMI (22%). In multivariate logistic regression analysis, being overweight (OR = 0.73; 95%CI: 0.58-0.91, P = .007) or obese (OR = 0.62; 95%CI: 50.45-0.85, P = .003) was associated with a reduced risk of ICU death. Being morbidly obese was independently associated with an increased risk of death in elective surgery patients whereas being underweight was independently associated with an increased risk of death in patients admitted for short-term monitoring and after elective surgery.

Conclusions

In this cohort, overweight and obese patients had a reduced risk of ICU death. Being underweight or morbidly obese was associated with an increased risk of death in some subgroups of patients.