Sexual activity as a risk factor for hepatitis C in Puerto Rico.

BACKGROUND: Hepatitis C (HCV) is a blood born infection that affects millions of people worldwide. Although IV drug use (IVDU) and blood transfusions have been clearly defined as transmission risk factors for HCV, the role of sexual transmission is still not clearly defined.

AIMS: To define the role of sexual transmission among Puerto Ricans HCV+ patients, and to determine if there is an association between sexual, and non-sexual risk factors, genotypes and viral load.

METHODS: A cross-sectional epidemiological IRB approved study was performed among patients with HCV+ enrolled from Nov-2001 to May-2002. The Puerto Rico Gastroenterology Association sponsored this study. Five hundred subjects completed a risk-factor study questionnaire. Blood samples were drawn to determine HCV genotype and viral load.

RESULTS: A male predominance was found (68%). Most patients (70%) were between 45-65 years old. The most common genotype was 1 (82%). Reported sexual risk factors were: sex with a drug user (30.3%), multiple sexual partners (>10) (28.9%), sex with an HCV infected partner (9.0%), and homosexuality (8.3%). Most common non-sexual risk factors were: blood transfusion (30.2%) and intravenous drug use (IVDU) (46.8%). Illicit drug users (IDU) reported having sex at a younger age (15.5 y/o), than those non-IDU (18.9 y/o) p=0.015. IDU reported both, a higher frequency of homosexual encounters than non-IDU (10.8% vs. 1.5%) p<0.0001, as well as having sex with another IDU (47.8% vs. 11.3%) p<0.0001. Those patients who reported sex with an HCV infected partner and were non-IDU had fewer partners than those who were IDU (1-2 vs. >20 partners) p<0.001. As a group, homosexuals had sex at a younger age, had multiple partners (> 20) and a higher proportion of sex with IVDU. After adjusting for age, gender, and risk factors, no significant association was found between genotype and sexual variables. The difference noted between groups in viral load had no statistical significance.

CONCLUSIONS: Our data supports that sexual risk factors are common in HCV infected patients. High risk sexual practices such as early sexual intercourse, homosexuality and multiple sexual partners are the most common in patients with hepatitis C with use of illicit drugs as a risk factor also. The role of sexual transmission in this group cannot be clearly established. No significant relationship was found between genotype, viral load and sexual transmission. Patients with illegal drug use (IDU) showed significant difference from non users in regard to the age of the first sexual intercourse, the number of sexual partners and the practice of sex with other illicit drug users or partners of the same sex. When parenteral transmission is excluded, practicing sex with a HCV infected partner was the only identified risk factor in 6.5% of the studied population.