Psychometric properties of the Arabic version of the Mini-Balance Evaluation Systems Test in patients with neurological balance disorders

OBJECTIVE

This study aimed to translate and cross-culturally adapt the Mini-Balance Evaluation Systems Test (Mini-BESTest) to Arabic (Mini-BESTest-Ar) and evaluate its psychometric properties in patients with neurological balance disorders.

PATIENTS AND METHODS

The translation and adaptation followed the established guidelines. Validity, internal consistency, test-retest reliability, standard error of measurement (SEM), minimal detectable change (MDC95), and limits of agreement (LOA) were examined in 56 patients. The sensitivity was investigated using the receiver operating characteristic curve.

RESULTS

The Mini-BESTest-Ar significantly correlated with the Berg balance scale (BBS) (r = 0.80; p < 0.001) and dynamic gait index (DGI) (rho = 0.75; p < 0.001). All domains showed moderate to very good correlations with BBS (r = 0.62-0.81; p < 0.001) and fair to very good correlations with DGI (rho = 0.4 -0.79; p < 0.05). The internal consistency and test-retest reliability of the total score and all domains were excellent (Cronbach's α = 0.96-0.81, ICC = 0.95-0.81, and r = 0.92-0.68). The SEM, MDC95, and MDC% for total score and domains were 1.19-0.31, 3.29-0.86 points, and 16.5%-66.8% respectively. The LOA revealed no systematic error. A cut-off point of 21.5/28 (Area under the curve = 0.85, sensitivity = 75%, specificity = 75%) was specified.

CONCLUSIONS

The Mini-BESTest-Ar has appropriate psychometric properties supporting its usefulness for research and clinical purposes.

A Model to Identify Sarcopenia in Patients With Cirrhosis

BACKGROUND & AIMS

The severe depletion of muscle mass at the third lumbar vertebral level (sarcopenia) is a marker of malnutrition and is independently associated with mortality in patients with cirrhosis. Instead of monitoring sarcopenia by cross-sectional imaging, we investigated whether ultrasound-based measurements of peripheral muscle mass, measures of muscle function, along with nutritional factors, are associated with severe loss of muscle mass.

METHODS

We performed a prospective study of 159 outpatients with cirrhosis (56% male; mean age, 58 ± 10 years; mean model for end-stage liver disease score, 10 ± 3; 60% Child-Pugh class A) evaluated at the Cirrhosis Care Clinic at the University of Alberta Hospital from March 2011 through September 2012. Lumbar skeletal muscle indices were determined by computed tomography or magnetic resonance imaging. We collected clinical data and data on patients' body composition, nutrition, and thigh muscle thickness (using ultrasound analysis). We also measured mid-arm muscle circumference, mid-arm circumference, hand grip, body mass index, and serum level of albumin; patients were evaluated using the subjective global assessment scale. Findings from these analyses were compared with those from cross-sectional imaging, for each sex, using logistic regression analysis.

RESULTS

Based on cross-sectional imaging analysis, 43% of patients had sarcopenia (57% of men and 25% of women). Results from the subjective global assessment, serum level of albumin, and most nutritional factors were significantly associated with sarcopenia. We used multivariate analysis to develop a model to identify patients with sarcopenia, and developed a nomogram based on body mass index and thigh muscle thickness for patients of each sex. Our model identified men with sarcopenia with an area under the receiver operating characteristic curve value of 0.78 and women with sarcopenia with an area under the receiver operating characteristic curve value of 0.89.

CONCLUSIONS

In a prospective study of patients with cirrhosis, we found that the combination of body mass index and thigh muscle thickness (measured by ultrasound) can identify male and female patients with sarcopenia almost as well as cross-sectional imaging (area under the receiver operating characteristic curve values of 0.78 and 0.89, respectively). These factors might be used in screening and routine nutritional monitoring of patients with cirrhosis.

A quantitative metabolomics profiling approach for the noninvasive assessment of liver histology in patients with chronic hepatitis C

Background

High-throughput technologies have the potential to identify non-invasive biomarkers of liver pathology and improve our understanding of basic mechanisms of liver injury and repair. A metabolite profiling approach was employed to determine associations between alterations in serum metabolites and liver histology in patients with chronic hepatitis C virus (HCV) infection.

Methods

Sera from 45 non-diabetic patients with chronic HCV were quantitatively analyzed using ¹H-NMR spectroscopy. A metabolite profile of advanced fibrosis (METAVIR F3-4) was established using orthogonal partial least squares discriminant analysis modeling and validated using seven-fold cross-validation and permutation testing. Bioprofiles of moderate to severe steatosis (≥33 %) and necroinflammation (METAVIR A2-3) were also derived. The classification accuracy of these profiles was determined using areas under the receiver operator curves (AUROCSs) measuring against liver biopsy as the gold standard.

Results

In total 63 spectral features were profiled, of which a highly significant subset of 21 metabolites were associated with advanced fibrosis (variable importance score >1 in multivariate modeling; R² = 0.673 and Q² = 0.285). For the identification of F3–4 fibrosis, the metabolite bioprofile had an AUROC of 0.86 (95 % CI 0.74–0.97). The AUROCs for the bioprofiles for moderate to severe steatosis were 0.87 (95 % CI 0.76–0.97) and for grade A2–3 inflammation were 0.73 (0.57–0.89).

Conclusion

This proof-of-principle study demonstrates the utility of a metabolomics profiling approach to non-invasively identify biomarkers of liver fibrosis, steatosis and inflammation in patients with chronic HCV. Future cohorts are necessary to validate these findings.

Electronic supplementary material

The online version of this article (doi:10.1186/s40169-016-0109-2) contains supplementary material, which is available to authorized users.

Emergency department visits for acetaminophen overdose: a Canadian population-based epidemiologic study (1997–2002)

Objective:

We describe the epidemiology of emergency department (ED) visits for acetaminophen overdose in a large Canadian health region, with a focus on sociodemographic risk factors and temporal trends.

Methods:

Patients presenting to an ED in the Calgary Health Region (population ~ 1.1 million) for acetaminophen overdose between 1997 and 2002 were identified using regional administrative data.

Results:

A total of 2699 patients made 3015 ED visits for acetaminophen overdose between 1997 and 2002, corresponding to an age- and sex-adjusted incidence of 45.7 per 100 000 population. Alcohol-related disorders were common (19%) and overdose rates were higher in females, younger patients, Aboriginals and social assistance recipients. The incidence decreased from 52.6 per 100 000 in 1997 to 35.1 per 100 000 in 2002 (34% relative reduction;p&lt; 0.0005). When classified according to suicidal intent, the rates of intentional and unintentional overdose (69% and 25% of all overdoses, respectively) showed similar temporal trends. A marked seasonality was observed, with a peak in spring and early summer.

Conclusions:

ED visit rates for acetaminophen overdose fell between 1997 and 2002. High-risk groups, including young females and marginalized populations, may benefit from preventive and educational initiatives.

Validation of the five-variable Model for End-stage Liver Disease (5vMELD) for prediction of mortality on the liver transplant waiting list

BACKGROUND

Modifications to the Model for End-Stage Liver Disease (MELD) have been proposed to improve prioritization of liver transplant (LT) candidates. Using a U.S. database, we derived a revised MELD including sodium and albumin [5-variable MELD (5vMELD)] that improved prediction of waiting list mortality. Our objectives were to confirm the association between hypoalbuminaemia and mortality and to externally validate 5vMELD in Canadian LT candidates.

METHODS

Among adults registered on the LT waiting list at the University of Alberta (01/2000-10/2009), Cox regression determined the association between albumin and 1-year waiting list mortality. The discrimination of MELD, MELDNa and 5vMELD for predicting 1-year mortality were compared using c-statistics.

RESULTS

Among 677 patients, 17% died and 51% underwent LT within 1 year of listing. Median serum albumin was 3.1 g/dl (IQR 2.6-3.6) and 70% of patients were hypoalbuminaemic (albumin <3.5 g/dl). One-year mortality in patients with normal serum albumin and hypoalbuminaemia were 14% and 29% respectively (P = 0.004). For patients with serum albumin between 2.0 and 4.0 g/dl, an approximately linear, inverse relationship was observed between albumin and 1-year mortality [adjusted hazard ratio (HR) 1.45; 95% CI 1.03-2.03; P = 0.03]. For this outcome, the c-statistic of 5vMELD (0.778) was superior to those of MELD (0.754) and MELDNa (0.765) (both P ≤ 0.05).

CONCLUSIONS

Hypoalbuminaemia is an independent predictor of mortality on the LT waiting list. Compared with MELD and MELDNa, 5vMELD improves prediction of mortality suggesting that modification of these scores to include serum albumin should be considered as a means of prioritizing LT candidates.

Liver stiffness by transient elastography predicts liver-related complications and mortality in patients with chronic liver disease

Background

Liver stiffness measurement (LSM) by transient elastography (TE, FibroScan) is a validated method for noninvasively staging liver fibrosis. Most hepatic complications occur in patients with advanced fibrosis. Our objective was to determine the ability of LSM by TE to predict hepatic complications and mortality in a large cohort of patients with chronic liver disease.

Methods

In consecutive adults who underwent LSM by TE between July 2008 and June 2011, we used Cox regression to determine the independent association between liver stiffness and death or hepatic complications (decompensation, hepatocellular carcinoma, and liver transplantation). The performance of LSM to predict complications was determined using the c-statistic.

Results

Among 2,052 patients (median age 51 years, 65% with hepatitis B or C), 87 patients (4.2%) died or developed a hepatic complication during a median follow-up period of 15.6 months (interquartile range, 11.0–23.5 months). Patients with complications had higher median liver stiffness than those without complications (13.5 vs. 6.0 kPa; P<0.00005). The 2-year incidence rates of death or hepatic complications were 2.6%, 9%, 19%, and 34% in patients with liver stiffness <10, 10–19.9, 20–39.9, and ≥40 kPa, respectively (P<0.00005). After adjustment for potential confounders, liver stiffness by TE was an independent predictor of complications (hazard ratio [HR] 1.05 per kPa; 95% confidence interval [CI] 1.03–1.06). The c-statistic of liver-stiffness for predicting complications was 0.80 (95% CI 0.75–0.85). A liver stiffness below 20 kPa effectively excluded complications (specificity 93%, negative predictive value 97%); however, the positive predictive value of higher results was sub-optimal (20%).

Conclusions

Liver stiffness by TE accurately predicts the risk of death or hepatic complications in patients with chronic liver disease. TE may facilitate the estimation of prognosis and guide management of these patients.

Survival after hepatic resection: impact of surgeon training on long-term outcome

BACKGROUND

Mortality for liver resection has remarkably improved owing to multiple factors. We sought to determine the impact of the various types of fellowship training on patient survival after liver resection.

METHODS

Patients who underwent hepatic resection between 1995 and 2004 in either the Calgary or Capital health regions (Edmonton) of Alberta, Canada, were identified using ICD-9 and -10 codes. Primary outcomes included in-hospital mortality and patient survival according to surgeon volume and training type (surgical oncology v. hepatobiliary v. others).

RESULTS

A total of 1033 patients underwent hepatic resection. Surgeon volume was not predictive of either in-hospital mortality (adjusted odds ratio 0.63, 95% confidence interval [CI] 0.32-1.20) or patient survival (unadjusted hazard ratio 1.11, 95% CI 0.82-1.51). Nonsignificance was also demonstrated for a surgeon's type of fellowship training.

CONCLUSION

The various modes of fellowship training do not appear to influence inhospital mortality or patient survival after hepatic resection.

B-cell depletion with rituximab in patients with primary biliary cirrhosis refractory to ursodeoxycholic acid

OBJECTIVES

Rituximab, an anti-CD20 monoclonal antibody that selectively depletes B cells, has shown promise in autoantibody-associated, immune-mediated disorders. As ursodeoxycholic acid (UDCA) is not successful in all patients with primary biliary cirrhosis (PBC), additional treatment options are necessary. The objective of this study was to assess the safety and efficacy of rituximab in patients with PBC refractory to UDCA.

METHODS

Fourteen PBC patients refractory to UDCA received two rituximab infusions (1,000 mg) 2 weeks apart. The primary efficacy outcome was normalization and/or 25% improvement in serum alkaline phosphatase (ALP) concentration at 6 months.

RESULTS

The median age was 53 years, and 92% were female and antimitochondrial antibody (AMA) positive. The median UDCA dosage was 15.3 mg/kg/day (interquartile range 14.5-17.8). Although rituximab was well tolerated, one patient withdrew due to an asthma exacerbation during the first infusion. Effective B-cell depletion was observed in the remaining 13 patients, including three that developed human anti-chimeric antibodies. ALP normalization and/or ≥ 25% improvement was observed in three patients (23%) at 6, 12, and 18 months. Significant reductions in median ALP (from 259 U/l at baseline to 213 U/l at 6 months; median decrease 16%), and serum IgM and AMA levels were observed at 6 months. Although fatigue was stable, pruritus improved in 60% of patients at 12 months (vs. 8% with worsening pruritus).

CONCLUSIONS

Selective B-cell depletion with rituximab was safe and associated with a significant decrease in autoantibody production, but had limited biochemical efficacy in PBC patients with an incomplete response to UDCA.

Hospital performance reports based on severity adjusted mortality rates in patients with cirrhosis depend on the method of risk adjustment

BACKGROUND

Hospital outcome report cards are used to judge provider performance, including for liver transplantation. We aimed to determine the impact of the choice of risk adjustment method on hospital rankings based on mortality rates in cirrhotic patients.

MATERIAL AND METHODS

We identified 68,426 cirrhotic patients hospitalized in the Nationwide Inpatient Sample database. Four risk adjustment methods (the Charlson/Deyo and Elixhauser algorithms, Disease Staging, and All Patient Refined Diagnosis Related Groups) were used in logistic regression models for mortality. Observed to expected (O/E) death rates were calculated for each method and hospital. Statistical outliers with higher or lower than expected mortality were identified and rankings compared across methods.

RESULTS

Unadjusted mortality rates for the 553 hospitals ranged from 1.4 to 30% (overall, 10.6%). For 163 hospitals (29.5%), observed mortality differed significantly from expected when judged by one or more, but not all four, risk adjustment methods (25.9% higher than expected mortality and 3.6% lower than expected mortality). Only 28% of poor performers and 10% of superior performers were consistently ranked as such by all methods. Agreement between methods as to whether hospitals were flagged as outliers was moderate (kappa 0.51-0.59), except the Charlson/Deyo and Elixhauser algorithms which demonstrated excellent agreement (kappa 0.75).

CONCLUSIONS

Hospital performance reports for patients with cirrhosis require sensitivity to the method of risk adjustment. Depending upon the method, up to 30% of hospitals may be flagged as outliers by one, but not all methods. These discrepancies could have important implications for centers erroneously labeled as high mortality outliers.

Risk of comorbidities on postoperative outcomes in patients with inflammatory bowel disease

BACKGROUND

The effect of comorbidities on postoperative outcomes in patients with inflammatory bowel disease (IBD) has not been explored adequately. We evaluated the prevalence of comorbidities and their effect on postoperative outcomes after an IBD-related operation.

METHODS

The Nationwide Inpatient Sample database was used to identify 35 588 patients with IBD who underwent an IBD-related operation from January 1, 1995, through December 31, 2005. The presence of comorbid illness was assessed using the Elixhauser index. Multiple logistic regression analysis was performed to evaluate the effect of comorbidities on mortality rate after adjusting for age, sex, race, health insurance status, and admission type. Linear regression models were used to evaluate health care resource use.

RESULTS

Postoperative mortality was 1.9%. As the number of comorbidities increased (ie, 0, 1, 2, or ≥3), postoperative mortality increased (0.4%, 1.5%, 3.3%, and 7.9%, respectively). Congestive heart failure (odds ratio, 3.50 [95% confidence interval, 2.63-4.62]), liver disease (3.15 [2.00-4.97]), thromboembolic disease (4.19 [3.37-5.21]), and renal disease (8.74 [5.44-14.05]) were associated with a significant increase in mortality rate. Comorbidities associated with an increased risk of mortality also were associated with a significant increase in length of stay and hospital charges.

CONCLUSIONS

Comorbidities were common in patients with IBD and they significantly increased the risk of postoperative mortality and health care use in patients with IBD.

Amoebic liver abscess in USA: a population-based study of incidence, temporal trends and mortality

BACKGROUND

Amoebic liver abscess (ALA) may be associated with significant morbidity and mortality, but nationwide American data is unavailable. Our objective was to describe ALA epidemiology and outcomes in USA from a population-based perspective.

METHODS

Patients hospitalized with ALA between 1993 and 2007 were identified using the Nationwide Inpatient Sample. Patient characteristics, interventions and outcomes including mortality were determined. The annual incidence of ALA and temporal trends were determined using the negative binomial regression models.

RESULTS

Between 1993 and 2007, 848 hospitalizations for ALA, corresponding to ∼4100 hospitalizations nationwide, were identified. The annual incidence was 1.38 per million population with a 2.4% [95% confidence interval (CI) 0-4.8%; P=0.06] average annual decline during this study. Most patients were hospitalized in western (54%) and southern states (27%), and 48% were Hispanic. Males (incidence rate ratio vs. females: 4.53; 95% CI 4.19-4.90) had the highest incidence rates. Percutaneous and surgical drainage was required in 48 and 7% of patients respectively. Although length of stay [median, 6 days; interquartile range (IQR) 4-10] and hospital charges (US$25,345; IQR US$15,030-42, 275) were substantial, in-hospital mortality was rare (0.8%). Females [odds ratio (OR) 6.12; CI 1.39-26.8], patients ≥ 60 years (OR 13.3; 95% CI 2.5-71.5), and those with ≥ 3 comorbidities (OR 5.80; 95% CI 1.30-25.8), particularly malnutrition, had an increased risk of death.

CONCLUSIONS

ALA is rare and the incidence has decreased in USA. Young, Hispanic males in southwestern states are most frequently affected. Mortality caused by ALA is lower than what was reported previously.

Elective resection of colon cancer by high-volume surgeons is associated with decreased morbidity and mortality

BACKGROUND

The purpose of this study was to determine whether morbidity and mortality in patients undergoing elective resection of colon cancer are associated with surgeon or hospital volume.

METHODS

Using the Nationwide Inpatient Sample database, we identified all adult patients who underwent elective resection for colon cancer as their primary procedure between 2003 and 2007. Cases were divided into three groups according to the mean number of resections performed annually by each surgeon: low volume (≤4/year), intermediate volume (5-9/year), or high volume (≥10/year). Annual hospital case-load was also categorized as low volume (≤30/year), intermediate volume (31-60/year), and high volume (≥61/year). Multiple logistic regression models were used to identify differences in morbidity and mortality.

RESULTS

A total of 54,000 patients underwent resection of colon cancer by 7,313 surgeons in 1,398 hospitals. After adjusting for important covariates including hospital volume, colon cancer resection by high-volume surgeons was an independent predictor of decreased morbidity (odds ratio [OR], 0.91; 95% CI, 0.85-0.97) and mortality (OR, 0.75; 95% CI, 0.65-0.86). Mortality was lowest among patients operated on by high-volume surgeons in high-volume hospitals (2.2% vs. 3.9%; OR, 0.56; 95% CI, 0.46-0.68).

CONCLUSIONS

In patients undergoing elective resection of colon cancer, procedures done by high-volume surgeons are associated with decreased morbidity and mortality.

Gender, renal function, and outcomes on the liver transplant waiting list: assessment of revised MELD including estimated glomerular filtration rate

BACKGROUND & AIMS

The Model for End-Stage Liver Disease (MELD) allocation system for liver transplantation (LT) may present a disadvantage for women by including serum creatinine, which is typically lower in females. Our objectives were to investigate gender disparities in outcomes among LT candidates and to assess a revised MELD, including estimated glomerular filtration rate (eGFR), for predicting waiting list mortality.

METHODS

Adults registered for LT between 2002 and 2007 were identified using the UNOS database. We compared components of MELD, MDRD-derived eGFR, and the 3-month probability of LT and death between genders. Discrimination of MELD, MELDNa, and revised models including eGFR for mortality were compared using c-statistics.

RESULTS

A total of 40,393 patients (36% female) met the inclusion criteria; 9% died and 24% underwent LT within 3 months of listing. Compared with men, women had lower median serum creatinine (0.9 vs. 1.0 mg/dl), eGFR (72 vs. 83 ml/min/1.73 m(2)), and mean MELD (16.5 vs. 17.2; all p <0.0005), but within most MELD strata, had higher bilirubin and INR. After adjusting for relevant covariates including creatinine and body weight, women were less likely than men to receive a LT (hazard ratio [HR] 0.85; 95% CI 0.79-0.87) and had greater 3-month mortality (HR 1.13; 95% CI 1.05-1.21). Revision of MELD and MELDNa to include eGFR did not improve discrimination for 3-month mortality (c-statistics: MELD 0.896, MELD-eGFR 0.894, MELDNa 0.911, MELDNa-eGFR 0.905).

CONCLUSIONS

Women are disadvantaged under MELD potentially due to its inclusion of creatinine. However, since including eGFR in MELD does not improve mortality prediction, alternative refinements are necessary.

The outcomes of pregnancy in patients with cirrhosis: a population-based study

BACKGROUND

The outcomes of pregnancy in patients with cirrhosis are poorly described. Our objective was to assess obstetric outcomes in cirrhotic women and their infants from a population-based perspective.

METHODS

We analysed the 1993-2005 US Nationwide Inpatient Sample database to identify obstetric hospitalizations among patients with cirrhosis (n=339) and controls matched on age, hospital and year (n=6625). The effect of cirrhosis on maternal and fetal outcomes was evaluated using regression models with adjustment for patient and hospital factors.

RESULTS

Between 1993 and 2005, 114 antepartum and 225 delivery admissions in cirrhotic patients were identified. The estimated mean number of deliveries nationwide increased from 68 to 106 annually between 1993 and 1999 and 2000 and 2005 (P=0.0004). Patients with cirrhosis were more likely to deliver by caesarean [42 vs. 28%; adjusted odds ratio (OR) 1.41; 95% confidence interval (CI) 1.06-1.88]. Maternal (1.8 vs. 0%; P<0.0001) and fetal mortality (5.2 vs. 2.1%; P<0.0001), antepartum admission (OR 2.97; 95% CI 2.24-3.96), and maternal (OR 2.03; 95% CI 1.60-2.57) and fetal complications (OR 3.66; 95% CI 2.74-4.88) were greater among cirrhotic patients than controls. Gestational hypertension, placental abruption and uterovaginal haemorrhage were more common in patients with cirrhosis; their infants had higher rates of prematurity and growth restriction. Hepatic decompensation occurred in 15%, including ascites in 11% and variceal haemorrhage in 5%. In women with decompensation, maternal and fetal mortality were 6 and 12% respectively.

CONCLUSIONS

Although rare, pregnancies among women with cirrhosis are increasing. Cirrhotic patients and their infants have an increased risk of obstetric complications, emphasizing the importance of close maternal-fetal monitoring during pregnancy.

Pregnancy outcomes among liver transplant recipients in the United States: a nationwide case-control analysis

Liver transplant recipients and their infants may have an increased risk of obstetric complications. Our objective was to describe pregnancy outcomes in women with a prior transplant from a population-based perspective. We analyzed the 1993-2005 US Nationwide Inpatient Sample database to identify obstetric hospitalizations among transplant recipients (n = 206) and controls matched by age, hospital, and year (n = 4060). The effect of prior transplantation on maternal and fetal outcomes was evaluated with regression models with adjustments for patient and hospital factors, including admission to a transplant center. Between 1993 and 2005, 146 delivery admissions among liver transplant recipients were identified. Cesarean deliveries were more common among transplant recipients (38% versus 24%; P = 0.0001); however, this difference was not significant after multivariate adjustment [OR (odds ratio) = 0.87; 95% confidence interval (CI) = 0.60-1.27]. Maternal mortality was similar among cases and controls (0% versus 0.02%; P = 1.00), but transplant patients had higher rates of fetal mortality (6.3% versus 2.0%; P = 0.0006), antepartum admission (OR = 2.27; 95% CI = 1.59-3.25), and maternal (OR = 2.63; 95% CI = 1.82-3.80) and fetal complications (OR = 2.49; 95% CI = 1.68-3.70). Gestational hypertension (30% versus 9%; P < 0.0001) and postpartum hemorrhage (8% versus 3%; P = 0.009) were more common among transplant recipients; their infants had higher rates of prematurity (27% versus 11%; P < 0.0001), distress (10% versus 5%; P = 0.005), and growth restriction (5% versus 2%; P = 0.05) but not congenital anomalies. Hospitalization in a transplant center ( approximately 50%) was associated with similar obstetric outcomes. In conclusion, although most pregnancy outcomes are favorable, liver transplant recipients and their infants have an increased risk of obstetric complications. Additional studies evaluating mechanisms aimed at reducing these complications are necessary.

Epidemiology and natural history of primary biliary cirrhosis in a Canadian health region: a population-based study

The recent epidemiology and outcomes of primary biliary cirrhosis (PBC) in North America are incompletely described, partly due to difficulties in case ascertainment. In light of their availability, broad coverage, and limited expense, administrative databases may facilitate such investigations. We used population-based administrative data (inpatient, ambulatory care, and physician billing databases) and a validated International Classification of Diseases coding algorithm to describe the epidemiology and natural history of PBC in the Calgary Health Region (population approximately 1.1 million). Between 1996 and 2002, the overall age/sex-adjusted annual incidence of PBC was 30.3 cases per million (48.4 per million in women, 10.4 per million in men). Although the incidence remained stable, the prevalence increased from 100 per million in 1996 to 227 per million in 2002 (P < 0.0005). Among 137 incident cases with a total follow-up of 801 person-years from diagnosis (median 5.8 years), 27 patients (20%) died and six (4.4%) underwent liver transplantation. The estimated 10-year probabilities of survival, liver transplantation, and transplant-free survival were 73% (95% confidence interval [CI] 60%-83%), 6% (95% CI 2.5%-12.6%), and 68% (95% CI 55%-78%), respectively. Survival in PBC patients was significantly lower than that of the age/sex-matched Canadian population (standardized mortality ratio 2.87; 95% CI 1.89-4.17); male sex (hazard ratio [HR] 3.80; 95% CI 1.85-7.82) and an older age at diagnosis (HR per additional year, 1.06; 95% CI 1.03-1.10) were independent predictors of mortality.

CONCLUSION

This population-based study demonstrates that the burden of PBC in Canada is high and growing. Survival of PBC patients is significantly lower than that of the general population, emphasizing the importance of developing new therapies for this condition.

Morbidity and mortality following coronary artery bypass graft surgery in patients with cirrhosis: a population-based study

BACKGROUND

The risk of cardiac surgery in patients with cirrhosis is poorly defined. Our objective was to describe outcomes of coronary artery bypass graft (CABG) surgery in cirrhotic patients from a population-based perspective.

METHODS

We analysed the 1998-2004 Nationwide In-patient Sample to identify patients hospitalized for CABG surgery. The effect of cirrhosis on mortality, complications, length of stay (LOS) and charges was evaluated using logistic regression models.

RESULTS

Between 1998 and 2004, there were 403 094 CABG admissions; 711 patients (0.2%) had cirrhosis. The average annual number of surgeries increased 4.2% [95% confidence interval (CI) 0.7-7.8] in cirrhotic patients, but decreased 5.5% (3.4-7.5) in non-cirrhotic patients. Patients with cirrhosis had an increased risk of mortality [17 vs. 3%; adjusted odds ratio (OR) 6.67; 95% CI 5.31-8.31], complications [43 vs. 28%; OR 1.99 (95% CI 1.72-2.30)] and greater LOS and charges (P<0.0001). Predictors of mortality included age over 60 (OR 2.21; 95% CI 1.31-3.73), female gender (OR 1.92; 95% CI 1.08-3.41), ascites (OR 3.80; 95% CI 1.95-7.39) and congestive heart failure (OR 1.75; 95% CI 1.08-2.84). Hospital volume and off-pump CABG did not affect mortality.

CONCLUSIONS

Patients with cirrhosis have an increased risk of morbidity and mortality following CABG surgery. Additional studies are necessary to refine risk stratification in this high-risk patient population.

Inflammatory bowel disease patients who leave hospital against medical advice: predictors and temporal trends

BACKGROUND

Leaving hospital against medical advice (AMA) may have consequences with respect to health-related outcomes; however, inflammatory bowel disease (IBD) patients have been inadequately studied. Thus, we determined the prevalence of self-discharge, assessed predictors of AMA status, and evaluated time trends.

METHODS

We analyzed the 1995-2005 Nationwide Inpatient Sample (NIS) to identify 93,678 discharges with a primary diagnosis of IBD admitted to the hospital emergently and did not undergo surgery. We described the proportion of IBD patients who left AMA. Predictors of AMA status were evaluated using a multivariate logistic regression model and temporal trend analyses were performed with Poisson regression models.

RESULTS

Between 1995 and 2005, 1.31% of IBD patients left hospitals AMA. Crohn's disease (CD) patients were more likely to leave AMA (adjusted odds ratio [aOR], 1.53; 95% confidence intervals [CI]: 1.30-1.79). Characteristics associated with leaving AMA included: ages 18-34 (aOR, 7.77, 95% CI: 4.34-13.89); male (aOR, 1.75; 95% CI: 1.55-1.99); Medicaid (aOR, 4.55; 95% CI: 3.81-5.43) compared to private insurance; African Americans (aOR, 1.34; 95% CI: 1.09-1.64) compared to white; substance abuse (aOR, 2.75; 95% CI: 2.14-3.54); and psychosis (aOR, 1.55; 95% CI: 1.13-2.14). The incidence rates of self-discharge for CD patients were stable (P > 0.05) between 1995 and 1999, while they significantly (P < 0.0001) increased after 1999. In contrast, AMA rates for UC patients remained stable during the study period.

CONCLUSIONS

Approximately 1 in 76 IBD patients admitted emergently for medical management leave the hospital AMA. These were primarily disenfranchised patients who may lack adequate outpatient follow-up.

Weekend versus weekday admission and mortality from gastrointestinal hemorrhage caused by peptic ulcer disease

BACKGROUND & AIMS

Management of upper gastrointestinal bleeding (UGIB) often requires urgent endoscopic intervention; limitations in its availability on weekends might be associated with increased mortality, compared with patients admitted on weekdays.

METHODS

We used the 1993-2005 U.S. Nationwide Inpatient Sample to identify patients hospitalized for UGIB caused by peptic ulceration. Differences in in-hospital mortality between patients admitted on weekends and weekdays were evaluated by using logistic regression models, adjusting for patient and clinical factors including the timing of upper endoscopy.

RESULTS

Between 1993 and 2005, there were 237,412 admissions to 3,166 hospitals for peptic ulcer-related UGIB. Compared with patients admitted on a weekday, those admitted on the weekend had an increased risk of death (3.4% vs 3.0%; adjusted odds ratio [OR], 1.08; 95% confidence interval [CI], 1.02-1.15), higher rates of surgical intervention (3.4% vs 3.1%; OR, 1.09; 95% CI, 1.03-1.15), prolonged hospital stays, and increased hospital charges (P < .0001 for all comparisons). Patients admitted on the weekend had a longer mean time to endoscopy (2.21 +/- 0.01 vs 2.06 +/- 0.01 days; P < .0001) and were less likely to undergo endoscopy on the day of admission (30% vs 34%; P < .0001). After adjusting for the timing of endoscopy, weekend admission remained an independent predictor of increased mortality (OR, 1.12; 95% CI, 1.05-1.20).

CONCLUSIONS

Patients admitted to hospital on the weekend for peptic ulcer-related hemorrhage have higher mortality and more frequently undergo surgery. Although wait times for endoscopy are prolonged in patients hospitalized on the weekend, this delay does not appear to mediate the weekend effect for mortality.

Predicting in-hospital mortality in patients with cirrhosis: results differ across risk adjustment methods

Risk-adjusted health outcomes are often used to measure the quality of hospital care, yet the optimal approach in patients with liver disease is unclear. We sought to determine whether assessments of illness severity, defined as risk for in-hospital mortality, vary across methods in patients with cirrhosis. We identified 258,731 patients with cirrhosis hospitalized in the Nationwide Inpatient Sample between 2002 and 2005. The performance of four common risk adjustment methods (the Charlson/Deyo and Elixhauser comorbidity algorithms, Disease Staging, and All Patient Refined Diagnosis Related Groups [APR-DRGs]) for predicting in-hospital mortality was determined using the c-statistic. Subgroup analyses were conducted according to a primary versus secondary diagnosis of cirrhosis and in homogeneous patient subgroups (hepatic encephalopathy, hepatocellular carcinoma, congestive heart failure, pneumonia, hip fracture, and cholelithiasis). Patients were also ranked according to the probability of death as predicted by each method, and rankings were compared across methods. Predicted mortality according to the risk adjustment methods agreed for only 55%-67% of patients. Similarly, performance of the methods for predicting in-hospital mortality varied significantly. Overall, the c-statistics (95% confidence interval) for the Charlson/Deyo and Elixhauser algorithms, Disease Staging, and APR-DRGs were 0.683 (0.680-0.687), 0.749 (0.746-0.752), 0.832 (0.829-0.834), and 0.875 (0.873-0.878), respectively. Results were robust across diagnostic subgroups, but performance was lower in patients with a primary versus secondary diagnosis of cirrhosis.

CONCLUSION

Mortality analyses in patients with cirrhosis require sensitivity to the method of risk adjustment. Because different methods often produce divergent severity rankings, analyses of provider-specific outcomes may be biased depending on the method used.

Impact of liver disease, alcohol abuse, and unintentional ingestions on the outcomes of acetaminophen overdose

BACKGROUND & AIMS

Acetaminophen overdose is the most common cause of acute liver failure in the U.S. and other Western countries. Unintentional overdoses, alcohol abuse, and underlying liver disease might increase the risk of hepatotoxicity. In this population-based study, we examined outcomes of acetaminophen overdose, with particular attention to these risk factors.

METHODS

Patients hospitalized for acetaminophen overdose between 1995 and 2004 were identified retrospectively by using administrative data. Comorbid conditions, suicidal intent, and hepatotoxicity were identified by using International Classification of Diseases-Ninth Revision-Clinical Modification and International Statistical Classification of Diseases and Health-Related Problems, 10th revision diagnostic codes.

RESULTS

During the 10-year interval, 1543 patients were hospitalized for acetaminophen overdose; 34% were alcohol abusers, 3% had liver disease, and 13% overdosed unintentionally. Seventy patients (4.5%) developed hepatotoxicity. Unintentional overdoses (odds ratio [OR], 5.18; 95% confidence interval [CI], 3.00-8.95), alcohol abuse (OR, 2.21; 95% CI, 1.30-3.76), underlying liver disease (OR, 3.50; 95% CI, 1.57-7.77), and N-acetylcysteine treatment (OR, 6.75; 95% CI, 2.78-16.39) were independently associated with hepatotoxicity. Fifteen patients (1.0%) died in-hospital; risk factors included older age, unintentional overdoses, alcohol abuse, comorbidities including liver disease, and hepatotoxicity (14% vs 0.3%; P < .0005). During a median follow-up of 5.2 years (range, 1 day-11.0 years), 79 patients (5.1%) died. Approximately half of these deaths were due to preventable conditions including suicide, substance abuse, and trauma.

CONCLUSIONS

In this population-based study, acetaminophen overdose had a relatively benign short-term course but was associated with substantial long-term mortality caused by preventable conditions. Acetaminophen-related hepatotoxicity is more common in patients with unintentional overdoses, alcohol abuse, and underlying liver disease.

Relationship between hospital volume and outcomes of esophageal variceal bleeding in the United States

BACKGROUND & AIMS

Esophageal variceal bleeding has a high mortality rate and requires complex management. High provider volume has been associated with improved outcomes for various surgical procedures and medical diagnoses, and volume-based referral has been advocated. The objective of this study was to assess the volume-outcome relationship in patients with esophageal variceal bleeding.

METHODS

We analyzed the 1998-2005 Nationwide Inpatient Sample to identify patients hospitalized for esophageal variceal bleeding. The effects of hospital volume on in-hospital mortality, length of stay (LOS), and hospital charges were evaluated by using logistic regression models with adjustment for demographic and clinical factors. Hospital volume was classified on the basis of the average annual number of esophageal variceal bleeding admissions during the study interval (low volume, <13; medium volume, 13-25; and high volume, >25).

RESULTS

Between 1998 and 2005, there were 36,807 hospitalizations in 2575 hospitals for esophageal variceal bleeding. The majority of the hospitals were low-volume centers (76%). Overall, in-hospital mortality was 10.9% (95% confidence interval [CI], 10.5%-11.4%), median LOS was 4 days (interquartile range, 2-6), and total per patient charges were $21,144 ($13,240-$36,533). Compared with low-volume centers, admission to a high-volume hospital was associated with an increased risk of death (11.9%; odds ratio, 1.16; 95% CI, 1.03-1.29), prolonged LOS, and increased total charges (P < .005). However, patients admitted to high-volume hospitals were more likely to have negative prognostic characteristics including male gender, non-white race, nonprivate health insurance, alcoholic cirrhosis, hepatic decompensation, and to have been transferred from another institution (P < .05). After adjusting for case mix, volume was not an independent predictor of in-hospital mortality (odds ratio vs low-volume: medium-volume, 0.96; 95% CI, 0.87-1.05; high-volume, 1.03; 95% CI, 0.92-1.15) or LOS; however, medium- and high-volume centers had increased total charges (P < .00005).

CONCLUSIONS

The volume-outcome relationship observed for some procedures and conditions does not apply to patients with esophageal variceal bleeding. Therefore, volume-based referral is not indicated to improve short-term outcomes in this condition.

Utilization rates, complications and costs of percutaneous liver biopsy: a population-based study including 4275 biopsies

BACKGROUND

Liver biopsy is an important tool in the management of patients with liver disease. Because biopsy practices may be changing, we studied patterns of use in a large Canadian Health Region. We aimed to describe trends in biopsy utilization and the incidence and costs of complications from a population-based perspective.

METHODS

Administrative databases were used to identify percutaneous liver biopsies performed between 1994 and 2002. Significant complications were identified by reviewing medical records of patients hospitalized within 7 days of a biopsy and those with a diagnostic code indicative of a procedural complication. Analyses of biopsy rates employed Poisson regression.

RESULTS

Between 1994 and 2002, 3627 patients had 4275 liver biopsies (median 1 per patient; range 1-12). Radiologists performed the majority (90%), particularly during the latter years (1994 vs. 2002: 73 vs. 98%; P<0.0001). The overall annual biopsy rate was 54.8 per 100 000 population with a 41% (95% CI 23-61%) increase between 1994 and 2002. Annual increases were greatest in males and patients 30-59 years. Thirty-two patients (0.75%) had significant biopsy-related complications (1994-1997 vs. 1998-2002: 1.28 vs. 0.44%; P=0.003). Pain requiring admission (0.51%) and bleeding (0.35%) were most common. Six patients (0.14%) died; all had malignancies. The median direct cost of a hospitalization for complications was $4579 (range $1164-29 641).

CONCLUSIONS

Liver biopsy rates are increasing likely owing to the changing epidemiology and management of common liver diseases. The similarity of the complication rate in our population-based study with estimates from specialized centres supports the safety of this important procedure.

FibroTest and FibroScan for the prediction of hepatitis C-related fibrosis: a systematic review of diagnostic test accuracy

BACKGROUND

The accurate diagnosis of hepatitis C virus (HCV)-related fibrosis is crucial for prognostication and treatment decisions. Due to the limitations of biopsy, noninvasive alternatives including FibroTest and FibroScan have been developed. Our objective was to systematically review studies describing the accuracy of these tests for predicting HCV-related fibrosis.

METHODS

Studies comparing FibroTest or FibroScan versus biopsy in HCV patients were identified via an electronic search. Random effects meta-analyses and areas under summary receiver operating characteristics curves (AUC) were examined to characterize test accuracy for significant fibrosis (F2-4) and cirrhosis. Heterogeneity was explored using meta-regression.

RESULTS

Twelve studies were identified, 9 for FibroTest (N = 1,679) and 4 for FibroScan (N = 546). In heterogeneous analyses for significant fibrosis, the AUCs for FibroTest and FibroScan were 0.81 (95% CI 0.78-84) and 0.83 (0.03-1.00), respectively. At a threshold of approximately 0.60, the sensitivity and specificity of the FibroTest were 47% (35-59%) and 90% (87-92%). For FibroScan (threshold approximately 8 kPa), corresponding values were 64% (50-76%) and 87% (80-91%), respectively. Methodological quality, the length of liver biopsy specimens, and inclusion of special populations did not explain the observed heterogeneity. However, the diagnostic accuracy of both measures was associated with the prevalence of significant fibrosis and cirrhosis in the study populations. For cirrhosis, the summary AUCs for FibroTest and FibroScan were 0.90 (95% CI not calculable) and 0.95 (0.87-0.99), respectively.

CONCLUSIONS

FibroTest and FibroScan have excellent utility for the identification of HCV-related cirrhosis, but lesser accuracy for earlier stages. Refinements are necessary before these tests can replace liver biopsy.

Validation of ICD-9-CM/ICD-10 coding algorithms for the identification of patients with acetaminophen overdose and hepatotoxicity using administrative data

Background

Acetaminophen overdose is the most common cause of acute liver failure (ALF). Our objective was to develop coding algorithms using administrative data for identifying patients with acetaminophen overdose and hepatic complications.

Methods

Patients hospitalized for acetaminophen overdose were identified using population-based administrative data (1995–2004). Coding algorithms for acetaminophen overdose, hepatotoxicity (alanine aminotransferase >1,000 U/L) and ALF (encephalopathy and international normalized ratio >1.5) were derived using chart abstraction data as the reference and logistic regression analyses.

Results

Of 1,776 potential acetaminophen overdose cases, the charts of 181 patients were reviewed; 139 (77%) had confirmed acetaminophen overdose. An algorithm including codes 965.4 (ICD-9-CM) and T39.1 (ICD-10) was highly accurate (sensitivity 90% [95% confidence interval 84–94%], specificity 83% [69–93%], positive predictive value 95% [89–98%], negative predictive value 71% [57–83%], c-statistic 0.87 [0.80–0.93]). Algorithms for hepatotoxicity (including codes for hepatic necrosis, toxic hepatitis and encephalopathy) and ALF (hepatic necrosis and encephalopathy) were also highly predictive (c-statistics = 0.88). The accuracy of the algorithms was not affected by age, gender, or ICD coding system, but the acetaminophen overdose algorithm varied between hospitals (c-statistics 0.84–0.98; P = 0.003).

Conclusion

Administrative databases can be used to identify patients with acetaminophen overdose and hepatic complications. If externally validated, these algorithms will facilitate investigations of the epidemiology and outcomes of acetaminophen overdose.

Diagnostic accuracy of the aspartate aminotransferase-to-platelet ratio index for the prediction of hepatitis C-related fibrosis: a systematic review

The development of noninvasive markers of liver fibrosis is a clinical and research priority. The aspartate aminotransferase-to-platelet ratio index (APRI) is a promising tool with limited expense and widespread availability. Our objective was to systematically review the performance of the APRI in hepatitis C virus (HCV)-infected patients. Random effects meta-analyses and areas under summary receiver operating characteristic curves (AUC) were examined to characterize APRI accuracy for significant fibrosis (stages 2-4) and cirrhosis. In 22 studies (n = 4,266), the summary AUCs of the APRI for significant fibrosis and cirrhosis were 0.76 [95% confidence interval (CI), 0.74-0.79] and 0.82 (95%CI, 0.79-0.86), respectively. For significant fibrosis, an APRI threshold of 0.5 was 81% sensitive and 50% specific. At a 40% prevalence of significant fibrosis, this threshold had a negative predictive value (NPV) of 80%, but could reduce the necessity of liver biopsy by only 35%. For cirrhosis, a threshold of 1.0 was 76% sensitive and 71% specific. At a 15% cirrhosis prevalence, the NPV of this threshold was 91%. Higher APRI thresholds had suboptimal positive predictive values except in settings with a high prevalence of cirrhosis. APRI accuracy was not affected by the prevalence of advanced fibrosis, or study and biopsy quality. However, the accuracy for cirrhosis was greater in studies including human immunodeficiency virus (HIV)/HCV-co-infected patients.

CONCLUSION

The major strength of the APRI is the exclusion of significant HCV-related fibrosis. Future studies of novel markers should demonstrate improved accuracy and cost-effectiveness compared with this economical and widely available index.

Hospitalizations for acetaminophen overdose: a Canadian population-based study from 1995 to 2004

BACKGROUND

Acetaminophen overdose (AO) is the most common cause of acute liver failure. We examined temporal trends and sociodemographic risk factors for AO in a large Canadian health region.

METHODS

1,543 patients hospitalized for AO in the Calgary Health Region (population ~1.1 million) between 1995 and 2004 were identified using administrative data.

RESULTS

The age/sex-adjusted hospitalization rate decreased by 41% from 19.6 per 100,000 population in 1995 to 12.1 per 100,000 in 2004 (P < 0.0005). This decline was greater in females than males (46% vs. 29%). Whereas rates fell 46% in individuals under 50 years, a 50% increase was seen in those >/= 50 years. Hospitalization rates for intentional overdoses fell from 16.6 per 100,000 in 1995 to 8.6 per 100,000 in 2004 (2004 vs. 1995: rate ratio [RR] 0.49; P < 0.0005). Accidental overdoses decreased between 1995 and 2002, but increased to above baseline levels by 2004 (2004 vs. 1995: RR 1.24;P < 0.0005). Risk factors for AO included female sex (RR 2.19; P < 0.0005), Aboriginal status (RR 4.04; P < 0.0005), and receipt of social assistance (RR 5.15; P < 0.0005).

CONCLUSION

Hospitalization rates for AO, particularly intentional ingestions, have fallen in our Canadian health region between 1995 and 2004. Young patients, especially females, Aboriginals, and recipients of social assistance, are at highest risk.

Impact of pharmaceutical industry versus university sponsorship on survey response: a randomized trial among Canadian hepatitis C care providers

BACKGROUND

Surveys originating from universities appear to have higher response rates than those from commercial sources. In light of the growing scrutiny placed on physician-industry relations, the present study aimed to determine the impact of the pharmaceutical industry versus university sponsorship on response to a postal survey completed by Canadian hepatitis C virus (HCV) care providers.

PATIENTS AND METHODS

In the present controlled trial, 229 physicians and nurses involved in HCV treatment were randomly assigned to receive a survey with sponsorship from a pharmaceutical company or university. The primary outcome was the proportion of completed surveys returned. The secondary outcomes included the response rate after the first mailing and the number of days taken to respond.

RESULTS

One hundred fifteen participants were randomly assigned to receive the pharmaceutical industry survey and 114 were assigned to receive the university survey. The final response rate was 72.9% (167 of 229), which did not differ between the industry and university groups (RR=0.91; 95% CI 0.78 to 1.07). Nurses (OR=2.20; 95% CI 1.08 to 4.48) and participants from an academic centre (OR=3.14; 95% CI 1.64 to 6.00) were more likely to respond. The response rate after the first mailing (RR=0.85; 95% CI 0.68 to 1.07) and the median number of days taken to respond (21 days in both groups; P=0.20) did not differ between the industry and university groups.

CONCLUSIONS

Pharmaceutical industry sponsorship does not appear to negatively impact response rates to a postal survey completed by Canadian HCV care providers.