Risk factors association of hepatitis C among women of reproductive age : a case control study at Quetta, Pakistan

Abstract

This case-control study was conducted to asses the risk factors for hepatitis C virus (HCV) infection among women of reproductive age at Bolan medical complex hospital (BMCH) and Sandeman provincial hospital (SPH), both in Quetta, Pakistan, during 1 December 2008 to 28 February 2009. The study subjects were 316 females of reproductive age (18 to 40 years), with cases HCV positive (158) and unmatched controls HCV negative (158) by Enzyme-Linked ImmunoSorbent (ELISA) laboratory reports. The potential risk factors considered were socio-demographic characteristics, past medical history, and obstetrical history. The data were collected by standardized, interviewer-administered questionnaires. Data were described with frequencies and percentages, and analyzed with logistic regression analysis, which gave odds ratios, 95% confidence intervals, and p-values. A bivariate analysis was conducted to explore associations of independent variables with HCV risk, and to select variables for subsequent multivariable analysis. In bivariate analysis, history of injections (in last month, last one year and last five years), place of injection (by dispenser and by unregistered personnel), lived with jaundice patient in household and personal jaundice ever were significantly positively associated with HCV risk. Family income was significantly associated negatively. Thirteen variables with p-value less than 0.2 in bivariate analysis were included in the multivariable logistic model. In multivariable analysis, health care injections in the last year, health care injections in the last five years, hospitalization for deliveries, injections by dispenser and by unregistered persons, and household contact with jaundice were associated positively and significantly with HCV risk. Family income and history of previous surgeries were associated negatively and significantly with HCV risk. In separate logistic models, the 13 independent variables were compared between the two study hospitals. This comparison showed significant or marginally significant (0.05<p<0.10) for 5 of 13 variables. Occupation and monthly family income showed positive significant positive association and living place and history of injections for last one month and for last one year showed significant negative association when BMCH was compared to SPH. The study was conducted in a specific population at two hospitals and some of the risk factors showed significant differences between these hospitals in the same city. Considering the above facts only these risk factors may not represent all the risk factors which lead to HCV infection in general population and all the hospitals of Pakistan. The observed negative association of HCV risk with surgery history was unexpected. This might partially reflect confounding with socioeconomic status; women with higher socioeconomic status (SES) were more likely to have had previous surgery than those with lower SES. It might also reflect confounding with post surgical consequences like increased numbers of injections and wound dressing by unregistered health practitioners and/or at home. However future research is needed to characterize the risk factors through community based studies at multiple locations. Further studies are also needed to explain the observed negative association of surgery history with HCV risk.