Patients with chronic hepatitis C virus infection are at a higher risk of being diagnosed with around 70% of the diseases captured by the ICD-10, according to a presentation at the International Liver Congress in Paris.
PhD, affiliate scientist at the Karolinska Institute and medical advisor for AbbVie, and colleagues used the ICD-10 classification B18.2 to identify patients with chronic hepatitis C (CHC) in the nationwide Swedish Patient Register (n = 42,522), including those receiving inpatient care, day surgery and nonprimary outpatient care, from 2001 through 2013.
“The study analyzed the risk for chronic hepatitis C patients to be diagnosed with other diseases using all the available diagnoses in the International Statistical Classification of Diseases (10th revision). Previous studies have mostly used established indexes, where the diagnoses are grouped into fewer categories,” Söderholm told Infectious Disease News. “Using indexes makes analyses more feasible, but as a consequence, the simplification increases the possibility of missing risks for specific diagnoses.”
The researchers pulled five non-CHC diagnosed age/sex/place of residency-matched comparators from the general population (n = 202,694), according to the presentation. Follow-up began at the time of diagnosis and was continued until death, emigration or the conclusion of the study on Dec. 31, 2013. The researchers calculated the risk for disease as standard incidence ratios (SIRs), and diseases were assessed as individual ICD-10 codes (n = 2,213) or grouped as blocks according to WHO (n = 264).
The results Söderholm presented showed that patients with CHC were at higher risk for 200 blocks of ICD-10 diagnoses — or 63%. The three disease groups for which patients with CHD were at the highest risk included viral hepatitis (B15-B19, excluding B18.2 [SIR = 86.1; 95% CI, 83.9-88.3]), liver disease (K70-K77 [SIR = 23.6; 95% CI, 23-24.3]) and HIV (B20-B24 [SIR = 21.6; 95% CI, 20.2-23.1]). Patients with CHC, researchers observed, were at an increased risk for 69% (1.112) of individual ICD-10 diagnoses.
Conversely, patients with CHC were at a lower risk (1.5%) for four blocks of diagnoses — demyelinating diseases of the central nervous system (G35-G37 [SIR = 0.43; 95% CI, 0.31-0.57]), glaucoma (H40-H42 [SIR = 0.74; 95% CI, 0.67-0.80]) malignant neoplasms of male genital organs (C60-C63 [SIR = 0.81; 95% CI, 0.73-0.90]) and radiation-related disorders of the skin and subcutaneous tissue (L55-L59 [SIR = 0.91; 95% CI, 0.83-0.99]). Overall, patients with CHC were at a lower risk for 1.2% (27) of individual ICD-10 diagnoses.
“My hope is that the study will provide an opportunity for clinicians and scientists to validate findings in their own dataset or to generate ideas for analyses in other countries,” Söderholm said. – by Marley Ghizzone
Söderholm J, et al. Abstract 394. Presented at: The International Liver Congress; April 11-15, 2018; Paris.
Disclosures: Söderholm is an employee of AbbVie and may own stocks or stock options in AbbVie, which provided financial support for the study. AbbVie participated in the study design, data/input analysis, interpretation of results, review, and approval of the publication. Please see the study for all other authors’ relevant financial disclosures.