Article

The Impact of ICD-9-CM Code Rank Order on the Estimated Prevalence of Clostridium difficile Infections

Department of Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA.
Clinical Infectious Diseases (Impact Factor: 9.42). 07/2011; 53(1):20-5. DOI: 10.1093/cid/cir246
Source: PubMed

ABSTRACT US estimates of the Clostridium difficile infection (CDI) burden have utilized International Classification of Disease, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis codes. Whether ICD-9-CM code rank order affects CDI prevalence estimates is important because the National Hospital Discharge Survey (NHDS) and the Nationwide Inpatient Sample (NIS) have varying limits on the number of ICD-9-CM codes collected.
ICD-9-CM codes for CDI (008.45), C. difficile toxin assay results, and dates of admission and discharge were collected from electronic hospital databases for adult patients admitted to 4 hospitals in the United States from July 2000 through June 2006. CDI prevalence per 1000 discharges was calculated and compared for NHDS and NIS limits and toxin assay results from the same hospitals. CDI prevalence estimates were compared using the χ(2) test, and the test of equality was used to compare slopes.
CDI prevalence measured by NIS criteria was significantly higher than that measured using NHDS criteria (10.7 cases per 1000 discharges versus 9.4 cases per 1000 discharges; P<.001) in the 4 hospitals. CDI prevalence measured by toxin assay results was 9.4 cases per 1000 discharges (P=.57 versus NHDS). However, the CDI prevalence increased more rapidly over time when measured according to the NHDS criteria than when measured according to toxin assay results (β=1.09 versus 0.84; P=.008).
Compared with the NHDS definition, the NIS definition captured 12% more CDI cases and reported significantly higher CDI rates. Rates calculated using toxin assay results were not different from rates calculated using NHDS criteria, but CDI prevalence appeared to increase more rapidly when measured by NHDS criteria than when measured by toxin assay results.

0 Followers
 · 
164 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The incidence of Clostridium difficile infection (CDI) is increasing among hospitalized patients. Liver transplantation (LT) patients are at higher risk for acquiring CDI. Small, single-center studies (but no nationwide analyses) have assessed this association. We used the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project (2004-2008) for this retrospective, cross-sectional study. Patients with any discharge diagnosis of LT composed the study population, and they were identified with International Classification of Diseases, Ninth Revision, Clinical Modification codes. Those with a discharge diagnosis of CDI were considered cases. Our primary outcomes were the prevalence of CDI and the effects of CDI on inpatient mortality. Our secondary outcomes included the length of stay and hospitalization charges. A regression analysis was used to derive odds ratios (ORs) adjusted for potential confounders. There were 193,174 discharges with a diagnosis of LT from 2004 to 2008. The prevalence of CDI was 2.7% in the LT population and 0.9% in the non-LT population (P < 0.001). Most of the LT patients were 50 to 64 years old. LT patients had higher odds of developing CDI [OR = 2.88, 95% confidence interval (CI) = 2.68-3.10]. Increasing age and increasing comorbidity (including inflammatory bowel disease and nasogastric tube placement) were also independent CDI risk factors. CDI was associated with a higher mortality rate: 5.5% for LT patients with CDI versus 3.2% for LT-only patients (adjusted OR = 1.70, 95% CI = 1.29-2.25). In conclusion, the prevalence of CDI is higher for LT patients versus non-LT patients (2.7% versus 0.9%). CDI is an independent risk factor for mortality in the LT population.
    Liver Transplantation 08/2012; 18(8):972-8. DOI:10.1002/lt.23449 · 3.79 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: GOALS:: To examine clinical outcomes in hospitalized Clostridium difficile infection (CDI) patients with acute kidney injury (AKI) using the National Hospital Discharge Survey for 2005 to 2009. BACKGROUND:: CDI can cause serious complications in hospitalized adults. On the basis of expert opinion, guidelines recommend AKI as a marker of severe CDI, but this has not been extensively validated. MATERIALS AND METHODS:: CDI and AKI patients were identified using International Classification of Diseases 9th edition codes. Weighted data analyses were performed to provide national estimates and compare outcomes in patients with AKI and CDI to CDI patients without AKI. RESULTS:: There were an estimated 1,261,712 patients with CDI identified with a median age of 75 years; 59.2% were female and 17.5% developed AKI. On multiple variable analysis, after adjusting for age, sex, and comorbid conditions, AKI was independently associated with length of hospital stay increase by 1.9 days, risk of colectomy with an odds ratio (OR) of 1.35, all-cause in-hospital mortality (OR, 2.76), and dismissal to a care facility (OR, 1.43), all P<0.0001. CONCLUSIONS:: These data support prior consensus opinion that AKI is an independent marker associated with adverse outcomes in CDI and provides key prognostic information.
    Journal of clinical gastroenterology 10/2012; 47(6). DOI:10.1097/MCG.0b013e31826af6fd · 3.19 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To examine the rate of Clostridium difficile infection (CDI) and hospital-associated outcomes in a national cohort of hospitalized patients with chronic kidney disease (CKD) and assess the impact of long-term dialysis on outcome in these patients. Data for January 1, 2005, through December 31, 2009 were obtained from the National Hospital Discharge Survey, which includes information on patient demographics, diagnoses, procedures, and discharge types. Data collected and analyzed for this study included age, sex, race, admission type (urgent or emergent combined vs elective), any colectomy diagnosis, length of stay, type of discharge, and mortality. International Classification of Diseases, Ninth Revision, Clinical Modification codes were utilized to identify CKD patients and CDI events. Weighted analysis was performed using JMP version 9. An estimated 162 million adults were hospitalized during 2005-2009, and 8.03 million (5%) had CKD (median age, 71 years). The CDI rate in CKD patients was 1.49% (0.119 million) compared with 0.70% (1.14 million) in patients without CKD (P<.001). Patients with CKD who were undergoing long-term dialysis were more than 2 times as likely to develop CDI than non-CKD patients and 1.33 times more likely than CKD patients not undergoing dialysis (all P<.001). In a weighted multivariate analysis adjusting for sex and comorbidities, patients with CKD and CDI had longer hospitalization, higher colectomy rate (adjusted odds ratio [aOR], 2.30; 95% confidence interval [CI], 2.14-2.47), dismissal to a health care facility (aOR, 2.22; 95% CI, 2.19-2.25), and increased in-hospital mortality (aOR, 1.55; 95% CI, 1.52-1.59; all P<.001) as compared with CKD patients without CDI. Patients with CKD who were undergoing long-term dialysis did not have worse outcomes as compared with CKD patients who were not undergoing long-term dialysis. These data suggest that patients with CKD have a higher risk of CDI and increased hospital-associated morbidity and mortality. Future prospective studies are needed to confirm these findings and to identify effective CDI prevention in CKD patients, who appear to have an increased risk of CDI acquisition.
    Mayo Clinic Proceedings 11/2012; 87(11):1046-53. DOI:10.1016/j.mayocp.2012.05.025 · 5.81 Impact Factor

Preview

Download
6 Downloads
Available from