Objective: To determine whether hepatitis C virus (HCV) infection status affected hospitalization rates, intensive care utilization rates, and discharge diagnoses between 1995 and 2000 in patients with HIV.
Methods: We conducted a prospective cohort study of 3730 HIV patients who were longitudinally followed between 1995 and 2000. All hospitalizations of these patients were classified as an opportunistic illness (OI) using the 1993 indicator diagnoses in the case definition of AIDS, complication of injection drug use (IDU) (abscess, cellulitis, osteomyelitis, bacteremia, endocarditis, and poisoning by analgesics), liver-related complication (acute and subacute necrosis of the liver, chronic liver disease and cirrhosis, liver abscess, hepatic coma, portal hypertension, hepatorenal syndrome, hepatocellular carcinoma, and gastrointestinal bleed), or other. Negative binomial regression was used to assess for risk factors for hospitalization.
Main outcome measures: Inpatient hospitalization and intensive care utilization rates and discharge diagnoses.
Results: Nearly half (42.8%) of our cohort was infected with HCV. Between 1995 and 2000, hospitalization rates for HCV-negative patients decreased from 61.9 to 33.9 per 100 patient-years (PY) of follow-up (P = 0.007). Hospitalization rates decreased between 1995 and 1997 for HCV-positive patients from 55.4 to 43.5 per 100 PY but increased between 1997 and 2000 from 43.5 to 62.9 per 100 PY (P = 0.001). When stratified by diagnostic category, IDU-related complications increased from 13.6 to 18.4 admissions per 100 PY and liver-related complications increased from 5.4 to 26.7 admissions per 100 PY between 1995 and 2000 in HCV-positive patients (P < 0.001); however, OIs remained relatively unchanged from 1995 to 2000, with 14.6 to 13.0 hospitalizations per 100 PY. In multivariate analysis, HCV infection (incidence rate ratio [IRR] = 1.75, 95% confidence interval [CI]: 1.47, 2.07), female gender (IRR = 1.56, 95% CI: 1.32, 1.85), age <37 years (IRR = 1.19, 95% CI: 1.01, 1.41), African American ethnicity (IRR = 1.30, 95% CI: 1.05, 1.61), and CD4 cell count <50 cells mm3 (IRR = 2.20, 95% CI: 1.72, 2.83) were predictive of hospitalization.
Conclusions: Our data indicate that hospitalization rates decreased significantly between 1995 and 2000 for HCV-negative patients but increased significantly for HCV-positive patients. Hospitalization rates for IDU- and liver-related complications increased during this time interval in coinfected patients. In the era of highly active antiretroviral therapy, HIV/HCV-coinfected patients are more likely to suffer from higher hospitalization rates, which will require more health care resources.