Importance and Contribution of Community, Social, and Healthcare Risk Factors for Hepatitis C Infection in Pakistan

Pakistan has a high prevalence of hepatitis C virus (HCV) infection, estimated at 4.9% (2,290/46,843) in the 2007 national HCV seroprevalence survey. We used data from this survey to assess the importance of risk factor associations with HCV prevalence in Pakistan. Exposures were grouped as community (going to the barbers, sharing smoking equipment, having an ear/nose piercing, tattoo, or acupuncture), healthcare (ever having hemodialysis, blood transfusion, or >= 5 injections in the last year), demographic (marital status and age), and socio-economic (illiterate or laborer). We used mutually adjusted multivariable regression analysis, stratified by sex, to determine associations with HCV infection, their population attributable fraction, and how risk of infection accumulates with multiple exposures. Strength of associations was assessed using adjusted odds ratios (aOR). Community [aOR females 1.5 (95% confidence interval [CI]: 1.2, 1.8); males 1.2 (1.1, 1.4)] and healthcare [females 1.4 (1.2, 1.6); males 1.2 (1.1, 1.4)] exposures, low socioeconomic status [females 1.6 (1.3, 1.80); males 1.3 (1.2, 1.5)], and marriage [females 1.5 (1.2, 1.9); males 1.4 (1.1, 1.8)] were associated with increased HCV infection. Among married women, the number of children was associated with an increase in HCV infection; linear trend aOR per child 1.06 (1.01, 1.11). Fewer infections could be attributed to healthcare exposures (females 13%; males 6%) than to community exposures (females 25%; males 9%). Prevalence increased from 3% to 10% when cumulative exposures increased from 1 to >= 4 [aOR per additional exposure for females 1.5 (1.4, 1.6); males 1.2 (1.2, 1.3)]. A combination of community, healthcare, and other factors appear to drive the Pakistan HCV epidemic, highlighting the need for a comprehensive array of prevention strategies.