The Association of Abnormal Liver Tests with Hepatitis C Testing in Primary Care

Background: As hepatitis C virus birth cohort (1945-1965) screening in primary care improves, testing patterns in response to persistently abnormal liver tests are less well known.

Methods: This retrospective cohort study of a patient-centered medical home between 2007 and 2016 evaluates the association of abnormal liver chemistries and other clinical and demographic factors with hepatitis C antibody (HCV Ab) testing in patients with persistently abnormal liver tests. Patients with at least 2 consecutive abnormal liver tests were categorized by the clinical pattern of liver chemistry abnormality, including cholestatic, hepatocellular, and mixed patterns. The primary outcomes were: 1) completed HCV Ab tests; and 2) positive HCV Ab results for those patients tested.

Results: Of 4512 patients with consecutive abnormal liver tests, only 730 (16%) underwent HCV Ab testing within 1 year of the second abnormality; 81/730 (11%) had HCV Ab detected. A logistic regression model revealed that mixed (odds ratio [OR] 2.20; 95% confidence interval [CI], 1.72-2.82) and hepatocellular (OR 1.43; 95% CI, 1.15-1.79) patterns of liver test abnormality, female sex, and alcohol and tobacco abuse were associated with higher odds of HCV Ab testing. Hepatocellular (OR 7.51; 95% CI, 2.18-25.94) and mixed patterns (OR 5.88; 95% CI, 1.64-21.15) of liver test abnormalities, male sex, Medicaid enrollment, and drug and tobacco abuse had higher odds of positive HCV Ab results.

Conclusions: There is opportunity to improve hepatitis C diagnostic testing in patients with consecutively elevated liver tests, and hepatocellular and mixed patterns of abnormality should prompt primary care providers to action.