Previous studies commonly define the age of older people living with HIV (PLWH) as 50 and above [1, 2]. Globally, the size of older PLWH has been rapidly increasing due to the advancement in the efficacy and coverage of antiretroviral therapy (ART) [3, 4]. For example, in the United States, the proportion of older PLWH over all PLWH was about 45% in 2014, and is projected to exceed 75% in 2030 [5]; in China, the number of newly diagnosed older PLWH has increased from 4,751 in 2010 to 19,815 in 2017, accounting for 7.4–14.7% of all newly reported HIV cases in the corresponding years, respectively [6].
Living with HIV can be extremely challenging at any age, and older PLWH is a more vulnerable group than younger PLWH because aging and HIV infection can work interactively to reduce human immune response [7]. This makes older PLWH more susceptible to many chronic diseases including cardiovascular, lung, liver and renal disease, cancers, and neuropsychiatric disorders. Older PLWH also have higher risk of diseases related to the acquired immune deficiency syndrome (AIDS), such as mycobacterium tuberculosis, pneumocystis jirovecii pneumonia, and toxoplasmosis [8, 9].
Mental health problems, such as depression and anxiety, are the most commonly reported comorbid conditions among PLWH [10]. Several studies have showed that mental health problems among older PLWH ranged from 27.7–74.2% in different countries [8, 11–13]. For example, 27.7% and 39.9% of older PLWH in Brazil and the United States suffered from major depression, respectively [11, 12]. In other cities in China, the prevalence of depressive symptom was 74.2% among older PLWH [8]. Such prevalence among older PLWH are higher than their younger counterparts [8, 11–13], due to age-related reduction in immune responses, impaired physical function, reduced social support, or difficulties in coping with HIV-related stress [8, 14]. Therefore, more attention should be given to this older PLWH [15–17].
Some studies have examined the factors associated with mental health problems among PLWH, including disease-related characteristics [e.g., CD4 cell counts [18–20], time since diagnosis [19, 20], and duration on antiretroviral therapy (ART) [19–22]], and psychosocial factors [e.g., social capital, loneliness, ageism, and HIV-related stigma [16, 23]]. Social capital, defined as the features of social organization such as trust, norms, and networks, is considered an fundamental driver of many other factors, which is especially true from a social epidemiology perspective [24–27]. Social capital can improve the efficacy of the society by facilitating the coordinated actions [27]. Some studies found an inverse association between social capital and mental health problems among PLWH [28–30]. However, such association may vary by age. For example, older PLWH, as a vulnerable population, are less likely to disclose their HIV sero-status to family, friends, relatives and health workers compared to their younger counterparts [8, 14]. This may make them feel more isolated and less supported by others, and thus lead to a different association between social capital and mental health. Nevertheless, to the best knowledge of the authors, none of the previous research has focused on this association among older PLWH. This gap is urgently needed to be filled, in order to design effective and efficient social capital-related interventions to improve mental health and health equity among older PLWH.
Using data recently collected from two districts/counties with high prevalence of HIV among the elderly in Sichuan Province of China [31–33], this study aimed to examine the association between social capital and mental health among older PLWH. The findings of this study will provide useful information for developing evidence-based interventions, to effectively build social capital for preventing mental health problems and hence improving the quality of life among older PLWH [34]. It is hypothesized that stronger social capital at individual/family and/or community/society level would be associated with lower prevalence of probable depression and probable anxiety among older PLWH.