Influence of overweight on ICU mortality: a prospective study

STUDY OBJECTIVE: Overweight patients seem to have a poorer outcome and a higher risk of complications during their stay in the ICU. We conducted a prospective study in order to examine the relationship between body mass index (BMI) and mortality among these patients. DESIGN: Prospective clinical study. SETTING: A 24-bed medical ICU in a university-affiliated hospital. METHODS: All patients hospitalized in the ICU over a 1-year period were included except those dying or being discharged from the hospital within 24 h of admission. Overweight patients were defined as those having a BMI > 75th percentile of this selected ICU population. Other data collected were demographic and ICU-related data. The Mann-Whitney test was used to compare numeric data between groups (ie, obese and nonobese populations). Variables that were significantly associated with ICU mortality by univariate analysis were entered into a multiple logistic regression model, allowing the determination of independent predictors. RESULTS: Eight hundred thirteen patients were included in the study. The limit of the upper quartile of the BMI was 27. This value was used to separate obese (n = 215) and nonobese (n = 598) groups. Significant differences between obese and nonobese patients were observed in age, length of stay in the ICU, simplified acute physiology score (SAPS) II, and ICU mortality. The observed mortality of obese patients was significantly higher than that predicted by SAPS II (32% vs 18%, respectively; p = 0.001). No difference was observed in frequency of nosocomial infection or duration of mechanical ventilation for mortality in ICU patients. Using a multivariate analysis, the predictive factors of mortality were SAPS II (p < 0.0001) and BMI > 27 (p < 0.01). CONCLUSION: This is the first prospective study showing high BMI value as an independent prognostic factor of mortality for ICU patients. The prognostic scoring systems currently in use, which were designed to predict the mortality of ICU patients, do not include BMI or do not consider obesity. These may underestimate, therefore, the risk for the specific population of obese patients.     

Postoperative morbidity, mortality, costs, and long-term survival in severely obese patients undergoing orthotopic liver transplantation

OBJECTIVE: Severely obese patients who undergo orthotopic liver transplantation are likely to have higher morbidity, mortality, costs, and a lower long-term survival. METHODS: This case-control study was done at a university hospital. One hundred twenty-one consecutive patients who underwent liver transplantation between 1994 and 1996 were studied. Severe obesity was defined as body mass index (BMI) more than 95th percentile (>32.3 for women and >31.1 for men), and moderate obesity was defined as BMI between 27.3 and 32.3 for women and 27.8 and 31.1 for men. The outcome measures were intraoperative complications, postoperative complications (wound infections, bile leak, vascular complications), length of hospital stay, costs of transplantation, and long-term survival RESULTS: The baseline characteristics, UNOS status, and cause of liver disease at the time of transplantation were similar in severely obese (n = 21, BMI = 37.4+/-4.8 kg/m2), obese (n = 36, BMI 28.7+/-0.9 kg/m2), and nonobese patients (n = 64, BMI 23.8+/-2.5 kg/m2). The intraoperative complications and transfusion requirements were similar in all three groups. The postoperative complications such as respiratory failure (p = 0.009) and systemic vascular complications (p = 0.04) were significantly higher in severely obese patients. The overall perioperative complication rate was 0.61 (39 of 64 patients) in nonobese patients, 0.77 (28 of 36 patients) in obese patients, and 1.43 (30 of 21 patients) in severely obese patients (p = 0.01). Infections were the leading cause of death in all groups accounting for 57-66% of deaths. The length of hospital stay was significantly higher in obese patients. The hospital costs of transplantation were higher ($30,000-$40,000) in severely obese patients than in nonobese patients. The long-term patient survival was similar between the groups (Kaplan-Meier analysis). CONCLUSIONS: Despite higher postoperative complications, severely obese patients have an acceptable long-term survival, which is comparable to nonobese patients. The cost of transplantation is higher among severely obese patients. There was no increased incidence of cardiovascular mortality among severely obese patients during the follow-up period.     

The relationship between obesity and mortality in patients with heart failure

OBJECTIVES: The study aimed to evaluate the role of obesity in the prognosis of patients with heart failure (HF). BACKGROUND: Previous reports link obesity to the development of HF. However, the impact of obesity in patients with established HF has not been studied. METHODS: We analyzed 1,203 patients with advanced HF followed in a comprehensive HF management program. The patients were subclassified into categories of body mass index (BMI) defined as: underweight BMI <20.7 (n = 164), recommended BMI 20.7 to 27.7 (n = 692), overweight BMI 27.8 to 31 (n = 168) and obese BMI >31 (n = 179). This sample size allows the detection of small effects (0.02), with a power of 0.80 and an alpha level of 0.05 for comparing one-year survival between BMI groups. RESULTS: The four BMI groups had similar profiles in terms of ejection fraction (mean 0.22), sodium, creatinine and smoking. The obese and overweight groups had significantly higher rates of hypertension and diabetes, as well as higher levels of cholesterol, triglycerides and low density lipoprotein cholesterol. The four BMI groups had similar survival rates. Ejection fraction, HF etiology and angiotensin-converting enzyme inhibitor use predicted survival on univariate analysis (p < 0.01), although BMI did not. On multivariate analysis, cardiopulmonary exercise tests, pulmonary capillary wedge pressure and serum sodium were strong predictors of survival (p < 0.05). Higher BMI was not a risk factor for increased mortality, but was associated with a trend toward improved survival. CONCLUSIONS: In a large cohort of patients with advanced HF of multiple etiologies, obesity is not associated with increased mortality and may confer a more favorable prognosis. Further studies need to delineate whether weight loss promotion in medically optimized patients with HF is a worthwhile therapeutic goal.     

Relation of body mass index to fatal and nonfatal cardiovascular events after cardiac rehabilitation

The aim of the present study was to determine whether body mass index (BMI) influences survival and recurrent cardiovascular events in a cardiac rehabilitation population. We followed 389 consecutive entrants to cardiac rehabilitation for 6.4 +/- 1.8 years. Patients were stratified into 3 groups: normal (BMI 18 to 24.9 kg/m(2)), overweight (BMI 25 to 29.9 kg/m(2)), and obese (BMI > or =30 kg/m(2)). Total and cardiovascular mortality were inversely associated with BMI category in bivariate models. However, only cardiovascular mortality was significant after adjustment for age and gender (p < 0.044), with cardiovascular death rates of 10% in normal, 8% in overweight, and 2% in obese patients. The rates of nonfatal recurrent events were 10% in normal, 24% in overweight, and 25% in obese patients. Our data indicate that BMI is inversely related to cardiovascular mortality but positively related to the risk of nonfatal recurrent events.     

Persistent increases of BAL neutrophils as a predictor of mortality following lung transplant

STUDY OBJECTIVES: To evaluate whether findings from surveillance bronchoscopy predict survival following lung transplantation. DESIGN: Retrospective review and analysis of 498 bronchoscopies with transbronchial biopsy (TBB) and BAL performed in 34 patients after lung transplantation. SETTING: University-based, tertiary referral medical center. PATIENTS: Thirty-four patients after lung transplantation. The mean age at transplantation was 49+/-9 years; 20 (59%) were female. Twenty-four (71%) underwent single and 10 (29%) underwent bilateral lung transplantation. The most common pretransplantation diagnostic groups were emphysema/COPD without concomitant alpha1-antiprotease deficiency (n = 13) and other obstructive disease processes (n = 10). INTERVENTIONS: Over follow-up, subjects underwent multiple bronchoscopies with TBB and BAL. The median number per subject was 15 (25 to 75% range 13 to 17). MEASUREMENTS AND RESULTS: We calculated the overall median BAL WBCs and median percent neutrophils (polymorphonuclear leukocytes [PMNs]) among all of the BALs performed for each subject. We then calculated the mean +/- SD of those median values. We used Cox proportionate hazards to assess mortality risk. The median overall follow-up observation period for the cohort was 560 days. There were 11 deaths during this period. Twenty-four subjects (71%) had acute rejection (AR) grades 2 to 4 (mild to severe), and nine (27%) had obliterative bronchiolitis (OB) diagnosed by TBB at any point. The mean value for BAL WBCs was 366+/-145 x 10(3) per milliliter; for percentage PMNs, the mean was 7+/-10%. Adjusting for age, gender, single vs bilateral lung transplantation, pretransplantation diagnostic group, presence of AR, presence of OB, BAL WBC concentration, and lymphocyte CD4/CD8 ratio, PMN percent was a significant predictor of mortality (p = 0.02). CONCLUSIONS: Ongoing inflammation manifested by an increased percentage PMNs over repeated bronchoscopies predicts mortality following lung transplantation. Biopsy data alone may be insufficient to identify posttransplantation patients at risk of poor outcome.     

Characteristics and outcomes of patients with sarcoidosis listed for lung transplantation

STUDY OBJECTIVES: To characterize the course of patients with advanced sarcoidosis who have been listed for lung transplantation and to identify prognostic factors for death while they are on the waiting list. DESIGN: Retrospective cohort study. SETTING: Tertiary-care university hospital. PATIENTS: Forty-three patients with sarcoidosis who have been listed for lung transplantation at the University of Pennsylvania Medical Center. METHODS: A multivariable explanatory analysis using a Cox proportional hazards model was performed to determine risk factors that are independently associated with mortality while patients await transplantation. RESULTS: Twenty-three of the 43 patients (53%) died while awaiting transplantation. The survival rate of listed patients (as determined by the Kaplan-Meier method) was 66% at 1 year, 40% at 2 years, and 31% at 3 years. In a univariate analysis, the following factors were significantly associated with death on the waiting list: PaO(2) < or = 60 mm Hg (relative risk [RR], 3.4; 95% confidence interval [CI], 1.2 to 9.3); mean pulmonary artery pressure > or = 35 mm Hg (RR, 3.2; 95% CI, 1.1 to 9.5); cardiac index < or = 2 L/min/m(2) (RR, 2.8; 95% CI, 1.2 to 6.6), and right atrial pressure (RAP) > or = 15 mm Hg (RR, 7.6; 95% CI, 3.0 to 19.3). Multivariable analysis revealed that RAP > or = 15 mm Hg was the only independent prognostic variable (RR, 5.2; 95% CI, 1.6 to 16.7; p = 0.006). Twelve patients underwent lung transplantation. Survival after transplantation determined by the Kaplan-Meier method was 62% at both 1 and 2 years, and 50% at 3 years. CONCLUSIONS: Patients with advanced sarcoidosis awaiting lung transplantation have a high mortality rate with a median survival of < 2 years. Mortality is most closely linked to elevated RAP. While earlier referral may diminish the mortality rate of patients on the waiting list for transplantation, further improvements in posttransplantation outcomes will be necessary to ensure that this procedure truly bestows a survival benefit.     

Does heart transplantation confer additional benefit over medical therapy to patients who have waited >6 months for heart transplantation?

Objectives. This study compared the survival of patients with heart failure who have waited > 6 months for heart transplantation with that of patients who undergo heart transplantation after a similarly prolonged waiting period.Background. There are little data describing outcome in patients with severe heart failure who have waited for extended periods of time on the heart transplant waiting list.Methods. Sixty-three consecutive patients who spent >6 months on the heart transplant waiting list were examined. Mean (± SD) age was 53 ± 9 years, mean left ventricular ejection fraction was 19 ± 6%, and all were taking digoxin and diuretic and vasodilator agents. Patients who underwent transplantation during the follow-up period were censored from the pretransplantation analysis, and their survival was examined as part of the posttransplantation phase of the study.Results. Of the 63 original patients examined, 25 underwent transplantation, 10 during inotropic or mechanical circulatory support. The pretransplantation mortality rate was 6% at 6 months after the 6-month milestone on the waiting list, 12% at 12 months and 22% at 18 months. The posttransplantation mortality rate was 5% at 6 months, 10% at 12 months and 24% at 18 months. There were no differences in survival at any time between the two phases of the study.Conclusions. Survival of patients who have survived >6 months on the heart transplant waiting list is generally good. Although heart transplantation did not appear to confer additional survival advantage over medical therapy, a large proportion of the patients who underwent transplantation were critically ill at the time of transplantation and would undoubtedly have died of progressive heart failure had they not undergone transplantation. We conclude that heart transplantation should still be considered a therapeutic alternative in patients with heart failure even after a prolonged waiting period on the heart transplant waiting list.     

Intermediate follow-up of pediatric heart transplant recipients with elevated pulmonary vascular resistance index

Objectives. This study examined perioperative and intermediate outcomes in pediatric cardiac transplant recipients who had elevated pulmonary vascular resistance indexes preoperatively.Background. Elevated pulmonary vascular resistance was associated with poor outcome in previous studies and constitutes a relative contraindication to transplantation. Few studies have evaluated this poor outcome risk factor in pediatric patients.Methods. To evaluate outcomes of nonneonatal transplant recipients, records were reviewed and divided into Group I (preoperative pulmonary vascular resistance index ≥6 units·m²) and Group II (pulmonary vascular resistance index <6 units·m²). Donor/recipient weight ratios, ischemic times, length of intensive care unit stay, posttransplantation infection rates, arrhythmia, response to pretransplantation vasodilator infusions and pulmonary vascular resistance indexes at the first and most recent posttransplantation biopsies were analyzed.Results. Group I (8 patients) had a mean (±SEM) pulmonary vascular resistance index of 11.5 ± 3.5 units·m²; Group II (29 patients) had a mean pulmonary vascular resistance index of 2.3 ± 0.4 units·m²(p < 0.002). Pulmonary vascular resistance index decreased from 12.3 ± 3.9 to 3.9 ± 0.9 units·m²(p < 0.05) in 7 Group I patients undergoing vasodilator infusion during pretransplantation catheterization. Thirty-six orthotopic heart transplantations were performed and one heterotopic transplantation. Donor weights exceeded recipient weights by 13% and 31% for Groups I and II, respectively (p > 0.25). Donor ischemic time was 215 min for Group I and 225 min for Group II (p > 0.75). Intensive care unit stay was 11.5 days in Group I and 15.1 days in Group II (p = 0.20). Infection rate was 38% in both groups (p > 0.80). Arrhythmias occurred in 90% of Group I and 42% of Group II (p < 0.03) patients. Pulmonary resistance index in Group I decreased from 11.5 ± 3.5 to 3.3 ± 1.2 units·m²(p < 0.03) by the first posttransplantation biopsy and have not changed subsequently. During 2.3 years (range 0.3 to 8.5) of follow-up, the mortality rate was 25% and 21% for Groups I and II, respectively (p > 0.80).Conclusions. Group I patients did not require significantly oversized donors, restricted donor locations or longer intensive care unit stays or have higher infection rates; however, arrhythmias were more frequent. Pulmonary resistance index normalized early after transplantation. Pulmonary vascular reactivity may be more important for survival than absolute resistance index.     

Impact of body mass index on outcomes following critical care

STUDY OBJECTIVES: To determine the impact of body mass index (BMI) on outcomes in critically ill patients. DESIGN: Retrospective analysis of a large multi-institutional ICU database. MEASUREMENTS: The influence of BMI classification (underweight, < 20 kg/m(2); normal [control subjects], 20 to 25 kg/m(2); overweight, 25 to 30 kg/m(2); obese, 30 to 40 kg/m(2); severe obesity, > 40 kg/m(2)) on hospital survival, functional status at hospital discharge, and ICU/hospital length of stay (LOS) was analyzed via multivariate analysis, adjusting for age, gender, type of hospital admission, and severity score (ie, simplified acute physiologic score [SAPS] II and mortality prediction model [MPM] at time zero). Univariate analysis also was performed according to the quartile of the severity score. All comparisons were to the normal BMI group. RESULTS: Of 63,646 patient datasets, 41,011 were complete for height, weight, and at least one of the two severity scores. We found increased mortality in underweight patients (odds ratio [OR] of death: SAPS group, 1.19; MPM group, 1.26) but not in overweight, obese, or severely obese patients. ICU and hospital LOS were increased in both the severely obese (OR of discharge: ICU, 0.81 and 0.84, respectively; hospital, 0.83 and 0.87, respectively) and underweight groups (OR of discharge: ICU, 0.96 and 0.94, respectively; hospital, 0.91 and 0.90, respectively). Only in the SAPS group did the obese group have increased ICU LOS (OR, 0.96) and hospital LOS (OR, 0.96). Functional status at discharge was impaired in underweight patients (OR of disability: ICU, 1.11; hospital, 1.19). Overweight patients had decreased discharge disability (OR of disability: SAPS, 0.93; MPM, 0.94), while the results in the obese group were discordant between the two severity score groups (SAPS, not significant; MPM, 0.91; p < 0.05 for all ORs). CONCLUSIONS: Low BMI, but not high BMI, is associated with increased mortality and worsened hospital discharge functional status. LOS is increased in severely obese patients and, to a lesser extent, in underweight patients. Patients in the overweight and obese BMI groups may have improved mortality and discharge functional status.     

Association of protein C and type 1 plasminogen activator inhibitor with primary graft dysfunction

BACKGROUND: Acute lung injury is characterized by hypercoagulability and impaired fibrinolysis. We hypothesized that lower protein C and higher type 1 plasminogen activator inhibitor (PAI-1) levels in plasma would be associated with primary graft dysfunction (PGD) after lung transplantation. Design: Prospective, multicenter cohort study. METHODS: We measured plasma levels of protein C and PAI-1 before lung transplantation and 6, 24, 48, and 72 h after allograft reperfusion in 128 lung transplant recipients at six centers. The primary outcome was grade 3 PGD (Pa(O(2))/Fi(O(2)) < 200 with alveolar infiltrates) 72 h after transplantation. Biomarker profiles were evaluated using logistic regression and generalized estimating equations. RESULTS: Patients who developed PGD had lower protein C levels 24 h posttransplantation than did patients without PGD (mean +/- SD [relative to control]: 64 +/- 27 vs. 92 +/- 41%, respectively; p = 0.002). Patients with PGD also had PAI-1 levels that were almost double those of patients without PGD at 24 h (213 +/- 144 vs. 117 +/- 89 ng/ml, respectively; p < 0.001). Throughout the 72-h postoperative period, protein C levels were significantly lower (p = 0.007) and PAI-1 levels were higher (p = 0.026) in subjects with PGD than in others. These differences persisted despite adjustment for potential confounders in multivariate analyses. Higher recipient pulmonary artery pressures, measured immediately pretransplantation, were associated with higher PAI-1 levels and increased risk of PGD. CONCLUSION: Lower postoperative protein C and higher PAI-1 plasma levels are associated with PGD after lung transplantation. Impaired fibrinolysis and enhanced coagulation may be important in PGD pathogenesis.     

Causes and risk factors for liver injury following bone marrow transplantation

GOALS: A retrospective study of pretransplantation risk factors predisposing to liver injury following bone marrow transplantation (BMT). BACKGROUND: Liver complications are a major cause of morbidity and mortality following BMT. Determination of the pretransplantation factors that are likely to lead to liver injury may allow earlier diagnosis after BMT and may possibly improve prognosis. STUDY: Medical records of BMT patients were reviewed, and results of serial liver function tests and HBV/HCV serology during the pre- and posttransplantation 1-year period were noted. Presence of liver injury was defined as alanine aminotransferase levels twice the upper limit of normal. Forty-four allogeneic and 17 autologous BMTs, performed between 1990 and 2000, were analyzed in the study. RESULTS AND CONCLUSION: One-year survival was 77% (34 of 44 patients) for allogeneic BMT and 52% (9 of 17 patients) for autologous BMT. Seventy-two percent (32 of 44) of allogeneic transplant recipients and 47% (8 of 17) of autologous transplant recipients had liver injury during the first year of BMT. The most frequent causes of liver injury were graft-versus-host disease and drug hepatotoxicity for allogeneic BMT and drug hepatotoxicity for autologous BMT. Fulminant hepatic failure occurred in one allogeneic transplant recipient who was a pretransplantation HBV carrier and led to death. Multivariate regression analysis showed that pretransplantation HBV/HCV positivity and pretransplantation elevated liver enzyme levels of any cause were predictive risk factors for post-BMT liver injury, and close follow-up, early diagnosis, and treatment are highly recommended for BMT patients with these risk factors.     

The association between body mass index and in-hospital outcome among patients with acute myocardial infarction—Insights from China Acute Myocardial Infarction (CAMI) registry

BackgroundThe relationship between body mass index (BMI) and in-hospital mortality risk among patients with acute myocardial infarction (AMI) remains controversial.Methods and ResultsWe included 35,964 patients diagnosed with AMI in China Acute Myocardial Infarction registry between January 2013 and December 2016. Patients were categorized into 4 groups according to BMI level: BMI <18.5, 18.5–24.9, 25–30, and ≥30 kg/m² for underweight, normal, overweight, and obese groups, respectively. Clinical data were extracted for each patient, and multivariable logistic regression analysis was used to examine the association between BMI level and in-hospital mortality. Compared with normal-weight patients, obese patients were younger, more often current smokers, and more likely to have hypertension, hyperlipidemia, and diabetes. Multivariable regression analysis results demonstrated that compared with normal group, underweight group had significantly higher in-hospital mortality (odds ratio [OR]: 1.34; 95% confidence interval [CI]: 1.06–1.69; p = 0.016), while overweight group (OR: 0.86; 95% CI: 0.77–0.97; p = 0.011) and obese group (OR: 0.65; 95% CI: 0.46–0.91; p = 0.013) had lower mortality. All subgroups showed a trend toward lower in-hospital mortality risk as BMI increased.ConclusionsOur study provided robust evidence supporting “obesity paradox” in a contemporary large-scale cohort of patients with AMI and demonstrated that increased BMI was independently associated with lower in-hospital mortality.     

Impact of body mass index on the five-year outcome of patients having percutaneous coronary interventions with drug-eluting stents

The purpose of this study was to assess the impact of body mass index (BMI) on clinical outcome of patients treated by percutaneous coronary intervention (PCI) using drug-eluting stents. Patients were stratified according to BMI as normal (<25 kg/m(2)), overweight (25 to 30 kg/m(2)), or obese (>30 kg/m(2)). At 5-year follow-up all-cause death, myocardial infarction, clinically justified target vessel revascularization (TVR), and definite stent thrombosis were assessed. A complete dataset was available in 7,427 patients, of which 45%, 22%, and 33% were classified according to BMI as overweight, obese, and normal, respectively. Mean age of patients was significantly older in those with a normal BMI (p <0.05). Incidence of diabetes mellitus, hypertension, and dyslipidemia increased as BMI increased (p <0.05). Significantly higher rates of TVR (15.3% vs 12.8%, p = 0.02) and early stent thrombosis (1.5% vs 0.9%, p = 0.04) were observed in the obese compared to the normal BMI group. No significant difference among the 3 BMI groups was observed for the composite of death/myocardial infarction/TVR or for definite stent thrombosis at 5 years, whereas the normal BMI group was at higher risk for all-cause death at 5 years (obese vs normal BMI, hazard ratio 0.74, confidence interval 0.53 to 0.99, p = 0.05; overweight vs normal BMI, hazard ratio 0.73, confidence interval 0.59 to 0.94, p = 0.01) in the multivariate Cox proportional hazard model. Age resulted in a linearly dependent covariate with BMI in the all-cause 5-year mortality multivariate model (p = 0.001). In conclusion, the "obesity paradox" observed in 5-year all-cause mortality could be explained by the higher rate of elderly patients in the normal BMI group and the existence of colinearity between BMI and age. However, obese patients had a higher rate of TVR and early stent thrombosis and a higher rate of other risk factors such as diabetes mellitus, hypertension, and hypercholesterolemia.     

Excess weight at time of presentation of myocardial infarction is associated with lower initial mortality risks but higher long-term risks including recurrent re-infarction and cardiac death

OBJECTIVES: To evaluate the influence of elevated body mass index (BMI) on short- and long-term survival following acute myocardial infarction (AMI). BACKGROUND: Recent studies suggest an obesity survival paradox in individuals undergoing percutaneous coronary intervention with better 30-day and 1-year outcomes in obese relative to normal weight patients. We tested a similar obesity paradox hypothesis following acute myocardial infarction. METHODS: Short- and long-term all-cause mortality, and risk of recurrent AMI were evaluated according to BMI status in 894 consecutive survivors of AMI <80 years of age admitted to the Mayo Clinic Coronary Care Unit between January 1, 1988 and April 16, 2001. Normal weight, overweight and obesity were defined as BMI <25, 25-29.9, and >30 kg/m(2), respectively. RESULTS: Overall mortality following hospital discharge was significantly lower in overweight and obese patients and was mostly attributable to lower 6-month mortality (adjusted HR = 0.47, P = 0.01 for BMI >25 kg/m(2)) relative to normal weight patients, while long-term mortality among 6-month survivors was similar in all 3 groups. The risk of recurrent AMI was higher in patients with BMI >25 kg/m(2) (adjusted HR = 2.30, P = 0.01). Overweight and obese patients were significantly more likely to die from cardiac rather than non-cardiac causes (P < 0.01). CONCLUSIONS: Following AMI, overweight and obese individuals although paradoxically protected from short-term death have a long-term mortality risk that is similar to normal weight individuals. Younger age at the time of initial infarction and fewer non-cardiovascular comorbidities presumably explain the short-lived obesity survival paradox following myocardial infarction.     

Hepatitis G virus infection in patients with hepatitis C virus infection undergoing liver transplantation

BACKGROUND & AIMS: Hepatitis G virus (HGV) is transmissible by blood transfusion, but its role in chronic liver disease is unknown. The aim of this study was to determine the prevalence of HGV infection in patients infected with hepatitis C virus (HCV) undergoing transplantation and evaluate the effects of HGV coinfection on the course of posttransplantation HCV infection. METHODS: One hundred twenty-four patients infected with HCV undergoing liver transplantation were studied. Serum samples were tested for HCV and HGV RNA; HCV RNA was quantitated by branched DNA assay, and HCV genotype was determined. RESULTS: The prevalence of pretransplantation and posttransplantation HGV infection was 24% and 28%, respectively. Pre-transplantation HGV infection was positively correlated with posttransplantation HGV infection (P < 0.001). Pretransplantation clinical features were not different in patients infected with HCV with and without HGV infection. Posttransplantation HCV RNA levels were not significantly different in patients with and without HGV coinfection, but HCV genotype 1b was more frequent in patients with HGV coinfection. There were no differences in the histological severity of posttransplantation liver disease, graft, and patient survival between patients with and without HGV infection. CONCLUSIONS: Although HGV coinfection is frequent in patients with end- stage HCV disease undergoing liver transplantation, there is no association between the presence of HGV coinfection and the severity of liver disease post-transplantation, graft, or patient survival. (Gastroenterology 1996 Dec;111(6):1569-75)     

The association between body mass index and clinical outcomes in acute lung injury

BACKGROUND: The association between body mass index (BMI) and outcomes in critically ill patients is unclear. Our objective was to determine the association between BMI and outcomes in a population-based cohort of patients with acute lung injury (ALI). METHODS: In a prospective cohort study of all ICU patients in King County, Washington, with ALI in 1 year (1999 to 2000), 825 patients had a BMI recorded. Using multivariate analysis, patients in the abnormal BMI groups were compared to normal patients in the following areas: mortality, hospital length of stay (LOS), ICU LOS, duration of mechanical ventilation, and discharge disposition. RESULTS: There was no mortality difference in any of the abnormal BMI groups compared to normal-weight patients. Severely obese patients had longer hospital LOS than normal-weight patients (mean increase, 10.5 days; 95% confidence interval [CI], 4.8 to 16.2 days; p < 0.001); this was accentuated when analysis was restricted to survivors (mean increase, 14.3 days; 95% CI, 7.1 to 21.6 days; p < 0.001). ICU LOS and duration of mechanical ventilation were also longer in the severely obese group when analysis was restricted to survivors (mean increase, 5.6 days; 95% CI, 1.3 to 9.8 days; p = 0.01; and mean increase, 4.1 days; 95% CI, 0.4 to 7.7 days, respectively; p = 0.03). Severely obese patients were more likely to be discharged to a rehabilitation or skilled nursing facility than to home. CONCLUSIONS: BMI is not associated with mortality in patients with ALI, but severe obesity is associated with increased morbidity and resource utilization in the hospital and after discharge.     

Obesity and its effect on survival in patients undergoing orthotopic liver transplantation in the United States.

Studies assessing morbidity and mortality in obese patients undergoing orthotopic liver transplantation (OLT) have produced conflicting results, mainly because of the small sample size. The objective of our study was to determine graft and patient survival in obese adults receiving OLT in the U.S. between 1988 through 1996 using the United Network for Organ Sharing (UNOS) database. Among the 23,675 transplantations performed during the 9-year study period, 18,172 (75%) patients fulfilled the inclusion criteria. Of these, 8,382 (46%) were nonobese (body mass index [BMI] < 25 kg/m(2)), 5,913 (33%) were overweight (BMI, 25.1-30 kg/m(2)), 2,611 (14%) were obese (BMI, 30.1-35 kg/m(2)), 911 (5%) were severely obese (BMI, 35.1-40 kg/m(2)), and 355 (2%) were morbidly obese (BMI, 40.1-50 kg/m(2)). The outcome measures assessed were immediate (30-day), 1-, 2-, and 5-year patient survival. Obese groups had a higher proportion of women, a greater prevalence of cryptogenic cirrhosis (P <.05) and diabetes (P <.05), and a higher serum creatinine. Primary graft nonfunction, and immediate, 1-year, and 2-year mortality were significantly higher in the morbidly obese group (P <.05). Five-year mortality was significantly higher both in the severely and morbidly obese subjects (P <.05), mostly as a result of adverse cardiovascular events. Kaplan-Meier survival was significantly lower in morbidly obese patients, and morbid obesity was an independent predictor of mortality. Obesity is associated with a significant increase in long-term mortality, mostly as a result of cardiovascular events. Weight loss should be recommended for all patients awaiting a liver transplantation, especially if their BMI is more than 35 kg/m(2).     

Prognostic impact of elevated pretransplantation serum ferritin in patients undergoing myeloablative stem cell transplantation

Iron overload could be a significant contributor to treatment-related mortality (TRM) for patients with hematologic malignancies undergoing hematopoietic stem cell transplantation (HSCT). We studied 590 patients who underwent myeloablative allogeneic HSCT at our institution, and on whom a pretransplantation serum ferritin was available. An elevated pretransplantation serum ferritin level was strongly associated with lower overall and disease-free survival. Subgroup multivariable analyses demonstrated that this association was restricted to patients with acute leukemia or myelodysplastic syndrome (MDS); in the latter group, the inferior survival was attributable to a significant increase in TRM. There was also a trend toward an increased risk of veno-occlusive disease in patients with high ferritin. Our results argue that iron overload plays an important role in transplantation outcome for patients with acute leukemia or MDS, as it does in thalassemia. They also suggest future prospective trials to examine the potential benefit of chelation therapy in this setting.     

Obesity and mortality in advanced chronic renal failure patients

A protective effect of obesity on the mortality of end-stage renal failure patients has been observed in several studies. Most of these studies have been based on prevalent dialysis population. The aim of the present study was to evaluate if obesity has beneficial effects on the survival of advanced chronic renal failure patients. The study group consisted of 376 patients (mean age 63 +/- 15 years) with advanced chronic renal failure not yet on dialysis. Obesity was defined as a body mass index (BMI) > or = 30 kg/m2. Grade of comorbidity was quantified by the method devised by Davies. Survival was analyzed as time from the referral to the predialysis outpatient clinic to patient death, censoring from contributing additional survival data to the analysis following transplantation. Kaplan-Meier analysis was used to test survival differences according to quartiles of BMI, and between obese and nonobese patients. Further analysis were performed, stratifying survival curves by comorbid scores, lean body mass, age, and sex. Cox proportional hazard regression models were used to investigate the best determinants of mortality, and the role of obesity adjusted for other covariates. Median survival time was 1,453 days. During the follow-up time, 158 patients (42%) died. Survival differences among quartiles of BMI were statistically significant (Breslow = 10.7, p = 0.017). Patients within the lowest and the highest quartiles of BMI had higher mortality than the rest of patients. Survival curves between obese and non-obese patients did not differ significantly. However, when patients without comorbidity were studied apart, those with obesity showed worse survival than the rest of patients (log-rank = 7.42, p = 0.0064). Since the effect of obesity on mortality did not follow a proportional hazard pattern throughout the study period, multivariable analysis for mortality was stratified by 18 months intervals. The variables which fitted the best model were: age (Hazard Ratio: 1.04), comorbid score (HR: 2.17), serum albumin (HR: 0.62), GFR at the study entry (HR: 0.91), male gender (HR: 1.48), and obesity (HR: 1.51). In conclusion, obesity had no survival benefit in patients with advanced chronic renal failure. Obesity had a noteworthy impact on early mortality of advanced chronic kidney disease patients without comorbidities.     

The impact of body mass index on short- and long-term outcomes inpatients undergoing coronary revascularization. Insights from the bypass angioplasty revascularization investigation (BARI)

OBJECTIVES: We sought to investigate the impact of body mass index (BMI) on short- and long-term outcomes after initial revascularization with percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass graft surgery (CABG). BACKGROUND: Equivocal results exist on the impact of BMI on the risk of in-hospital complications after PTCA or CABG, and no long-term mortality data exist from a large series of revascularized patients. METHODS: From the randomized series and observational registry of the Bypass Angioplasty Revascularization Investigation (BARI), 2,108 patients who had PTCA and 1,526 patients who had CABG were evaluated by taking their BMI at study entry. They were classified as follows: low (< 20 kg/m(2)), normal (20 to 24.9 kg/m(2)), overweight (25 to 29.9 kg/m(2)), class I obese (30 to 34.9 kg/m(2)) and class II/III obese (greater-than-or-equal 35 kg/m(2)). In-hospital complications and short- and long-term mortalities were compared between levels of BMI within each mode of initial revascularization. RESULTS: Among patients who had PTCA, each unit increase in BMI was associated with a 5.5% lower adjusted risk of a major in-hospital event (death, myocardial infarction, stroke, coma); among patients who had CABG, no difference in the in-hospital outcome was observed according to BMI. In contrast, BMI was not associated with five-year mortality in the PTCA group; among the CABG group, adjusted relative risks of five-year cardiac mortality according to levels of BMI were 0.0 (low), 1.0 (normal), 2.02 (overweight), 3.16 (class I obese) and 4.85 (class II/III obese) (linear p < 0.001).CONCLUSIONS: Body mass index appears to have a differential impact on short- and long-term outcomes after coronary revascularization. These results underscore the need for further research to identify factors responsible for the apparent short-term protective effect of a higher BMI in patients undergoing PTCA and to study the impact of weight reduction on the long-term survival of obese patients undergoing CABG.