[Survey on extramarital sexual behaviors and HIV infection in middle-aged and elderly people aged 50 and above in selected areas of Chongqing].

Objective To know the situation of extramarital sexual behaviors and HIV infection in middle-aged and elderly people in Chongqing, and provide reference for AIDS prevention and treatment. Methods From October to December 2017, a multi-stage sampling method was used to recruit middleaged and elderly people aged ≥50 years who lived in Dazu and Hechuan districts of Chongqing for at least one year, with a sample size of 410. Face-to-face questionnaires survey and HIV antibody test were conducted. Results A total of 408 people were surveyed, including 313 males and 95 females aged 50-88 (64.93±9.03) years. The HIV infection rate was 1.47% (6/408), with the rate of 1.28% (4/313) in males and 2.11% (2/95) in females. The awareness rate of AIDS related knowledge was 37.50% (153/408). And 18.87% (77/408) of subjects surveyed reported extramarital sexual behaviors, 7.60% (31/408) reported extramarital sexual behaviors in the past half year, the constant condom use rate was 19.35% (6/31). The results of multivariate logistics model analysis on extramarital sexual behaviors showed that the prevalence in males were 39.51 times higher than that in females (OR=39.51, 95%CI: 5.03-310.30), 4.60 times higher in those who were unmarried, divorced or widowed than that in the married or cohabitants (OR=4.60, 95%CI: 1.50-14.05), 2.03 times higher in those with outside activities than those with individual activities (OR=2.03, 95%CI: 1.08-3.81) and 3.94 times higher in those with self-evaluation of emptiness of living state than that in those with engaged life (OR=3.94, 95%CI: 1.86-8.36). Conclusions The prevalence of extramarital sexual behavior in middle-aged and elderly people in some counties and districts in Chongqing is high. The factors such as gender, marital status, leisure activities, and self-evaluation of living state were related to the prevalence of extramarital sexual behaviors in this population. The condom use rate in extramarital sexual behavior was low. It is necessary to take effective interventions in this population. Key words: HIV; Middle-aged and elderly people; Extramarital sexual behavior