Introduction
Globally, along with antiretroviral therapy (ART) scale-up, mortality and new cases of HIV decreasing results in increased prevalence of HIV since 2006.1 By December 2020, there are approximately 37.7 million people living with HIV/AIDS (PLHIV) worldwide,2 among which 8.1 million are older (≥50 years old),3 and it is estimated that in some country, the percentage of older male PLHIV will rise to 73% by 2030.4 There are about 1.40 million PLHIV in China,5 the number of newly reported older PLHIV in China has been steadily increasing,6 7 from 32 850 to 66 010 during 2015-2019,8 at a much higher rate than the general population and other age groups,9 and heterosexual transmission has been identified as the major route.6 7 10 There are 486.58 million older population in China in 2020, accounting for 34.52% of the whole population.11 According to a meta-analysis study, during 2010–2018, HIV infection rate in older people is 1.68% in China and 2.13% in west part of China.12 Compared with other age groups, older men have minimal knowledge about HIV/AIDS,13 and condom use among them is extremely low.14 15 Currently, HIV-related health education (HRHE) and behavioural intervention among older people in China mainly adopts the knowledge-attitude-behaviour (KAP) model, and the knowledge and ability reservation of health educators are generally insufficient.10
Older men, whose sexual activities decline obviously after the age of 5016 and who were excluded from the priority of HIV prevention programmes,17–20 were not recognised and listed as a key prevention group until 201721 in China. Due to convention22 and stigma,23 sex has been taken as procreation within a family context in China. Chinese, especially older people, do not talk about sex.22 24 Since the 1980s, when migrating alone, due to a lack of norms and values’ control from original communities,14 22 25–30 sexual attitudes in China have changed to being an individual’s responsibility as long as there is no foreseen negative impact on the well-being of others or the larger society.22 Having sexual behaviour is not only to fulfil physical needs but also emotional needs.14 22 25–30 The closer clients feel with female sex workers (FSW), the less they use condom consistently.14 Moreover, it is estimated that men who have sex with men (MSM) account for 1.73% of men aged 18–64 years in China.31 In 2013, 17.9% of MSM reported that they had sex with both men and women (MSM/W), and living in Chengdu was identified as a risk factor.32
Conventionally, Chinese society is a patriarchy society where men are supposed to be strong and ready to give support to their intimate social networks.33 34 Social support which helps to maintain well-being35–38 for older men in China is insufficient. It is not clear the role of social and sexual network overlap in HIV Infection among older men from rural China. In order to find out the roles of sexual behaviours, sexual identity, health education, and especially social and sexual network overlap in HIV Infection among older men from rural China, a case–control study was conducted.