1 Gut Group, Division of Molecular and Clinical Medicine, School of Medicine, University of Dundee, Dundee, Scotland.
2 Department of Gastroenterology, NHS Tayside, Ninewells Hospital, Dundee, Scotland.
3 Public Health Directorate, NHS Tayside, Kings Cross Hospital, Dundee, Scotland.
There is emerging evidence that Hepatitis C (HCV) treatment engagement is associated with change in drug behaviours and reduced drug related death rates amongst people who inject drugs (PWID). The project aims to investigate whether HCV diagnosis and treatment engagement reduces all-cause mortality and drug related death, and whether any effect is dependent on treatment regimen and intensity of engagement with staff. Case control studies comparing: PWID with active HCV infection (PCR Positive) to PWID HCV infected but spontaneously resolved (PCR Negative); PCR Positive patients who engaged with treatment services to non-engagers; and patients who received interferon vs direct acting antiviral (DAA) based treatment. No differences in risk of all-cause mortality or drug related death between PCR Negative controls and PCR Positive cases were detected. The odds of all-cause mortality was 12.2 times higher in non-engaging persons compared to treatment engaging cases (aOR 12.15, 95% CI 7.03- 20.99, p < 0.001). The odds of a drug related death was 5.5 times higher in non-engaging persons compared to treatment engaging cases (aOR 5.52, 95% CI 2.67- 11.44, p < 0.001). No differences in risk of all-cause mortality or drug related death between interferon treated cases and DAA treated controls were detected. HCV treatment engagement is significantly protective against all-cause mortality and drug related death. This engagement effect is independent of treatment regimen, with the introduction of DAA therapies not increasing risk of drug related death, suggesting intensity of HCV therapy provider interaction is not an important factor.