Systemic lupus erythematosus (SLE) patients are more likely to have a chronic hepatitis C virus (HCV) infection than those without lupus, according to a study.
The research, “Chronic hepatitis C viral infection among SLE patients: the significance of coexistence,” was published in the journal Immunologic Research.
Israeli researchers used a health maintenance organization’s electronic medical records to investigate possible links between SLE and HCV. Clalit Health Services’ records included such information as patients’ age, gender, socioeconomic status, smoking status, and disease diagnoses.
The lupus group included those who had “at least one documented diagnosis of SLE in the medical records,” researchers said. The team randomly selected individuals without an SLE diagnosis for a control group. Controls were matched with SLE patients by gender and age.
Researchers compared the records of 5,018 patients diagnosed with SLE and 25,090 age- and sex-matched controls.
The rate of HCV infection in SLE patients was three times higher than in controls, they discovered. The figures were 1.06% of all SLE patients, versus 0.39% of all controls.
SLE patients between 40 and 59 years old were the most likely to have HVC.
The results showed a significant association between SLE and HCV infection. Researchers also found a connection between HCV and smoking and alcohol abuse.
Previous studies using much smaller patient cohorts had also found a higher rate of HCV infection in SLE patients. The association was more likely to occur in older men.
The size of the latest study was a major strength of the research, the authors wrote. It “presented the proportion of patients with the SLE HCV comorbidity of a very large number of patients with SLE,” they wrote, adding: “We found the same male predominance among HCV” as earlier studies.