Theme: Epidemiology & Public Health Research Year: 2022
Background:
Unstable housing has been found to increase risk of acquisition of hepatitis C virus (HCV) infection.
Methods to estimate people experiencing unstable housing on a population level are lacking. To
address this limitation, we developed an algorithm to identify people experiencing unstable housing
using administrative health data, and determined the HCV prevalence among this population.
Methods:
We used the British Columbia (BC) Hepatitis Testers Cohort (HTC), which includes all individuals
tested for or diagnosed with HCV in BC since January 1st, 1996 (~1.7 million people), linked to
prescription drugs, medical visits, hospitalizations, and mortality data until December 31st,
2015. International Classification of Diseases (ICD) versions 9 and 10 codes associated with
unstable housing were identified in the literature. We assessed the number of people from
2010-2015 with >2 encounters where any unstable housing-related ICD 9/10 codes appeared in
that year. Among those experiencing unstable housing each year, anti-HCV prevalence since
1996 was determined.
Results:
The number of people each year experiencing unstable housing increased from 2,691 to 11,296 from
2010 to2015 (Figure 1). A lower proportion of males (50%) and people aged over 55 years (36%) was
observed among those experiencing unstable housing in 2015, compared to 2010. HCV prevalence
among people experiencing unstable housing decreased each year (from 19% to 13%). In 2015, the
HCV prevalence among people experiencing unstable housing in BC was 13.05%, equating to 8,577
people; approximately 17% of all people diagnosed with HCV living in the province at that time.
Conclusion:
These findings indicate that HCV infection is highly prevalent among people experiencing unstable
housing in BC. Reasons for the decline in HCV prevalence among people experiencing unstable
housing in the BC-HTC require further investigation, as well as additional work to better understand
the profile & characteristics of people experiencing unstable housing who are diagnosed with HCV
infection.
Disclaimer and disclosure of Interest Statement:
All inferences, opinions, and conclusions drawn are those of the authors, and do not necessarily
reflect the opinions or policies of the authors’ affiliated organizations or data stewards. SB has
spoken and consulted for Gilead Sciences Canada Inc & AbbVie Canada (no personal payments
accepted), and has received unrestricted, investigator-initiated funding through her institution from
Gilead Sciences Canada Inc. MK has received grant funding via his institution from Roche Molecular
Systems, Boehringer Ingelheim, Merck, Siemens Healthcare Diagnostics and Hologic Inc. All other
authors have nothing to declare.