Drug-induced acute liver disease

Abstract

We performed a case-control study with the aims of documenting the ability of Medicaid data to be used to study acute liver disease, to determine the incidence rate of idiopathic liver disease resulting in hospitalization, and to evaluate the relationship between nonsteroidal anti-inflammatory drugs and acute liver disease. We reviewed the medical records of 408 Medicaid patients age 20 or older with an ICD-9-CM inpatient billing code consistent with acute hepatitis. We calculated the incidence rate of acute hepatitis resulting in hospitalization. After excluding patients with other forms of liver disease or in whom a diagnosis could not be confirmed, 107 cases were eligible for the case-control analysis. The annual incidence rate (95 per cent confidence interval) of acute idiopathic symptomatic hepatitis resulting in hospitalization was 2.2 (2.0–2.4) per 100,000 per year. Nine cases (8.4 per cent) and 26 controls (6.1 per cent) were exposed to nonsteroidal anti-inflammatory drugs, yielding an odds ratio of 1.4 (0.6–3.1). After adjustment for potential confounding variables, the odds ratio was 1.2 (0.5–2.8). We conclude that Medicaid billing data has high reliability and validity for the diagnosis of acute liver disease. However, primary medical records are essential for the study of drug-induced hepatitis. Acute symptomatic idiopathic liver disease severe enough to result in hospitalization is uncommon, and no association was evident between nonsteroidal anti-inflammatory drugs and acute hepatitis.