Background
People living with HIV taking combination antiretroviral therapy are reaching life expectancies parallel to HIV-negative populations [
1,
2]. An estimated 30% of Canadians with HIV are 50 years or older and in 2014, an estimated 45% of people with HIV in the United States were aged ≥ 50 years, 27% aged ≥ 55 years, and 6% aged 65 and older [
3,
4]. Similarly in the United Kingdom (UK), over half of people receiving HIV care will be 50 years or older by 2028 [
5]. Similar trends have been projected in other countries with access to HIV treatment [
6].
Even with improvements to survival, more individuals are living with a multitude of health-related concerns from HIV, aging and multimorbidity, including cardiovascular, liver and metabolic diseases, osteoporosis, and neurocognitive impairments [
6‐
8]. From a rehabilitation science perspective, these health challenges, are described as ‘disability’ [
9]. Disability can be episodic, exemplified by periods of illness and health that occurs over time [
9]. The Episodic Disability Framework is a conceptual framework derived from, and validated with adults living with HIV. The Framework characterizes disability as a combination of symptoms and impairments (physical, cognitive, mental-emotional), difficulties carrying out daily activities, challenges with social inclusion and uncertainty or worrying about future health that can be experienced by an individual [
9,
10]. Disability episodes can be amplified by extrinsic (e.g., experiencing stigma or absence of support) and intrinsic (e.g., aging, multimorbidity) contextual factors, adding further complications to the disability experience for people with HIV [
11]. While the Episodic Disability Framework provided insights into the components that comprise disability, the way in which dimensions of disability relate to each other is unknown.
Measuring disability is essential for ascertaining the nature and extent of health challenges that comes from living with HIV and its associated multimorbidity, and the effectiveness of interventions for their ability to diminish or prevent disability. Authors of a systematic review explored disability among people with HIV in sub-Saharan Africa and found that 73% of included studies reported lower levels of function in HIV positive compared to HIV negative comparator groups, and a prevalence of 25% physical impairments in mobility and motor function among people with HIV [
12]. Myezwa and colleagues (2009) described disability among people with HIV in the South African and Brazilian contexts, of which most commonly reported impairments included mental health function, fatigue and sleep health disorder [
13]. Among adults hospitalized with HIV in South Africa, 100% experienced at least one or more impairment [
14]. A provincial survey of people with HIV living in British Columbia, Canada found that the majority (more than 80%) of participants reported living with at least one impairment, activity limitation or social participation restriction; however, this study was conducted before the surge of multimorbidity associated with HIV and aging, likely underestimating the health complexities increasingly faced by older adults with HIV [
15,
16]. Collectively these approaches to disability assessment in South Africa, Brazil, and Canada were guided by the International Classification of Functioning, Disability and Health (ICF) [
17], which was not derived from the viewpoint of adults with HIV, and developed before the introduction of combination antiretroviral therapy; hence it may not fully encapsulate disability as experienced among those aging with HIV. Furthermore, the ICF suggests inter-relationships exist between all components of disability indicated with bidirectional arrows making it difficult to interpret for clinicians targeting interventions [
17]. Better understanding the strength and direction of relationships among elements that comprise the broader concept of disability will help to identify precise areas for targeting interventions to most effectively reduce disability.
We examined relationships between components of disability using data from the Ontario HIV Treatment Network Cohort Study (OCS) using variables that resembled dimensions of disability within the Episodic Disability Framework, such as scores from symptom and quality of life questionnaires [
18]. Results from this analysis indicated that physical and mental health challenges and difficulties carrying out daily activities either directly or indirectly predicted having challenges with social participation. However, we were unable to consider uncertainty in this analysis, a unique element of disability in the Episodic Disability Framework, because no questionnaires in the OCS captured this concept.
The HIV Disability Questionnaire (HDQ) is an HIV-specific patient-reported outcome measure of disability that was derived from the Episodic Disability Framework to assess disability presence, severity and episodic nature among adults living with HIV [
19,
20]. The HDQ demonstrated sensibility, validity and reliability with people living with HIV in Canada, Ireland and the United States [
21‐
24]. The HDQ is well suited for use by researchers, clinicians and community members to better understand the nature and extent of disability and the impact of aging with HIV with multimorbidity. Our aim was to characterize the disability experience and to examine the relationships between six dimensions of disability, specifically physical, cognitive, mental and emotional symptoms, difficulties carrying out day-to-day activities, uncertainty, and challenges to social inclusion among adults with HIV.
Discussion
Results illustrate the first known profile of disability experienced by adults with HIV using the HDQ, a unique HIV-specific patient-reported disability questionnaire. Uncertainty and worrying about the future with HIV was a key dimension of disability for participants in this study. Uncertainty as conceptualized by the Episodic Disability Framework, and measured by the HDQ refers to the extent an individual worries about when a potential episode of illness might occur, the severity and potential outcomes of an illness, and the impact worrying about future health with HIV may have on life decisions such as returning to work, purchasing a home, initiating new relationships, or starting a family [
9]. Uncertainty may be experienced with difficulty identifying sources of health challenges, particularly given new and emerging health challenges may be attributed to a combination of HIV, chronic inflammation, long-term antiretroviral use, multimorbidity, and aging. This can pose challenges when trying to identify interventions to address the source of disability. Authors who qualitatively examined the disability experience among 49 older men and women living with HIV identified uncertainty as a vital feature of episodic disability. They attributed uncertainty to unknown causes of health-related challenges, lack of or newly emerging knowledge and skills about HIV and aging among health providers, financial and housing insecurity, and concern about who will meet their caregiving needs as they get older with HIV [
35,
36].
However, some argue uncertainty can be beneficial for adopting strategies of hope and optimism and stimulate considerations for advanced care planning with a chronic terminal illness [
37‐
39]. Uncertainty can incite ways for individuals to adopt attitudes of hope and optimism and ‘live in the present’ rather than allowing the threat of a terminal illness to overburden and weigh on the mind [
37,
38]. Perrett and Biley (2013) used qualitative approaches with adults living with HIV to establish theory focused on ‘negotiating uncertainty’ comprised of seven categories ranging from ‘anticipating hopelessness’ to ‘regaining optimism’ [
39]. Solomon and colleagues (2018) identified six themes to define successful aging with HIV, some of which directly refer to strategies for living with uncertainty such as: acceptance, remaining positive, maintaining social connections and support with others, taking responsibility and control of health, keeping up a healthy lifestyle, and taking part in meaningful activities [
40].
Mental and emotional health challenges was a prominent mediator between uncertainty to challenges to social inclusion, and the second most severe dimension of disability. This aligns with anxiety and depression (mental health) that was reported as the most common concurrent health condition by 42% of respondents. The prevalence of depression and anxiety can be as high as 72 and 82% among people with HIV, respectively [
41]. As social isolation is a concern for adults aging with HIV [
36,
42], it is critical for health providers to consider approaches for addressing mental health challenges and uncertainty.
Episodic health challenges among respondents most commonly occurred in the physical and mental and emotional health domains including fatigue (30%), feeling sad, down or depressed (26%), diarrhea (26%); headaches (27%); aches and pains (26%), trouble sleeping (26%); and feeling anxious (25%). These results are similar to the most prevalent, distressing and burdensome symptoms measured with a group of adults with HIV in the United States [
43]. Fatigue is correlated with depression and is more prevalent among people with HIV compared to the general population [
41,
44]. Our sample similarly indicated fatigue and depression were among the highest reported and severely experienced health challenges. Physical and mental health challenges identified as episodic in this study (fatigue, feeling sad, down or depressed, feeling anxious, headaches, aches and pains, and trouble sleeping) highlight specific symptoms and impairments in which health professionals can tailor interventions to help mitigate the sometimes fluctuating nature of disability for adults with HIV.
Uncertainty emerged as an important direct and indirect predictor of experiencing mental-emotional health challenges and having challenges participating in society (social inclusion) with HIV. These findings build on our previous SEM work [
18] with the OCS study [
45], where “physical symptoms and impairments, mental-emotional health symptoms impairments, and difficulties with day-to-day activities directly or indirectly predicted challenges to social inclusion for adults living with HIV” [
18]. Data in this prior study were derived from instruments that measured constructs that resembled disability (e.g. quality of life, symptom indices) but did include measures of uncertainty [
18]. Hence, this study builds on this work to include and highlight the critical importance of uncertainty in the disability experience.
Interestingly, physical and cognitive health challenges had minimal to no effect on social inclusion after taking uncertainty and mental-emotional health challenges into account. Earlier work identified the prominent role of mental health in mediating the link between physical symptoms to challenges to social inclusion [
18]. Oberje and colleagues (2015) examined relationships between components of HRQL and subjective well-being (defined as life satisfaction, affective experiences and mood) and found mental health was one of the strongest direct predictors of self-reported well-being opposed to physical health, which was only weakly associated [
46]. Nevertheless, physical symptoms and impairments should not be ignored [
47]. Collectively, results suggest the interplay between all dimensions of disability, and in particular, the prominence of uncertainty and mental and emotional health in determining social inclusion for adults living with HIV.
Results from this study possess theoretical implications by broadening our understanding of disability as articulated in the Episodic Disability Framework [
9]. Our original development of the Framework derived from qualitative inquiry suggested relationships exist between disability dimensions, but the nature, extent and direction of those relationships were unknown. Hence, this work helps to further our understanding of disability by highlighting uncertainty as a key dimension and its predictive influence on mental health and social inclusion. Our analysis focused on examining relationships of dimensions of disability that comprise our core concept of interest as defined by the Episodic Disability Framework [
9]. We did not consider the influence of contextual factors on dimensions of disability [
11]. Positive coping and social support can positively influence satisfaction with life and work, motivation, and gratification (defined as global function), whereas stigma can negatively influence global function among adults living with HIV [
48]. Socioeconomic factors (education, health insurance, employment) and lifestyle factors (smoking, physical activity) also may influence self-reported disability [
49]. Future research should examine the influence that extrinsic (support, stigma) and intrinsic factors (age, sex, gender, sexual orientation, multimorbidity, living strategies) have on dimensions of disability in order to identify potential interventions to mitigate or prevent disability.
Respondents in this study were living with multiple coexisting health conditions. Respondents had a median of three health conditions, and 72% of the sample were living with ≥ 2 simultaneous health conditions. With the most common simultaneous health conditions of mental health (42%), muscle pain (33%), and joint pain (30%), we expect that disability reported by respondents was attributed to HIV, multimorbidity, and associated treatments, although items on the HDQ do not ascertain the source of health challenges. Disentangling the source of disability is important for future work. Almost half of the HHRS sample was ≥ 50 years of age. With the increase in life expectancy, more people aging with HIV will be living with increasing multimorbidy and associated health challenges [
6,
8]. Greater burden of comorbidity is associated with lower physical HRQL [
50]. For instance, older adults with HIV reported lower physical HRQL; but greater comorbidity burden was not associated with poorer mental health quality of life scores across age groups [
50]. These results suggest that despite greater comorbidity with age, older adults may have adopted resilience and self-management strategies to alleviate mental and emotional health challenges living with HIV [
51].
Frailty is an increasingly important consequence of HIV and aging associated with greater morbidity and mortality compared with HIV-negative controls [
52‐
55]. Only 6% of the HHRS sample reported living with frailty as a concurrent health condition, which may be due to participants’ lack of knowledge that they may be living with this condition, and the nature of frailty assessment and classification [
56]. Erlandson and colleagues (2014) identified an association between frailty and difficulty with instrumental activities of daily living, such as housekeeping and transportation, suggesting that difficulties with day-to-day activities may become increasingly prominent as adults age with HIV and frailty [
53]. There is an increasing need for interprofessional approaches involving infectious disease, gerontology and rehabilitation disciplines to work collectively in addressing the complexity of health challenges among those aging with HIV [
57].
Implications for clinical practice
Results from this work highlight the importance for clinicians and community members to consider uncertainty and its impact on mental health, function and social inclusion for adults aging with HIV. Collectively, health providers have a role in targeting efforts to address uncertainty by discussing concerns, values and priorities that may pertain to worrying about one’s future health aging with HIV. This dialogue can help to provide support to those struggling with uncertainty by acknowledging the reality of living with a chronic and sometimes unpredictable episodic illness [
37].
Implications for future research
This study provides the groundwork for further disability research in the context of HIV. Our analytical focus in this study was on the core concept of disability, however future modeling may determine the influence of extrinsic (e.g. social support, stigma) and intrinsic contextual factors (e.g. living (or coping) strategies) on dimensions of disability [
11]. Our findings will help empirically to identify areas for targeting interventions to mitigate disability experienced by adults with HIV. Forthcoming work also should consider adjusting for personal characteristics such as age, sex, gender, time since diagnosis and type of comorbidities to examine whether they moderate the relationships between different dimensions of disability.
We measured disability using a self-reported outcome measure opposed to performance-based measures of function and disability focused on assessing activities of daily living tasks and motor skills [
58]. The HDQ enabled us to capture self-reported performance on function and mobility as well as perceptions of mental and emotional health challenges and uncertainty, which are difficult domains to ascertain using performance based measurement approaches. While not specific to HIV, evidence supports the assertion that self-reported and performance-based assessments of activities of daily living measure related, but distinct aspects of ability [
59]. Nevertheless, considering both performance-based (functional ability) and perception-based assessments of disability are important for predicting complex health challenges in the ‘real world’ context. Future research may consider a combination of objective and self-reported approaches for measuring disability in the context of aging with HIV.
Limitations
This study was comprised of a convenience sample of adults with HIV recruited primarily from community service organizations across Canada, comprised largely of gay men living in urban geographical areas. While the largest proportion of respondents were from Ontario, which similarly reflects the province with the highest HIV prevalence rates in Canada [
3], our study was not bilingual, which limited the inclusion of French-speaking residents of Quebec and Newfoundland and Labrador; thus findings do not characterize disability among the broader population of adults with HIV in Canada. Future work is underway to examine the influence of gender on the disability experience. The meaning of the HDQ scores should be considered prudently given the interpretability (or clinical importance) of the scores is unclear. The episodic nature of health challenges may be overestimated due to the large rate of missing responses; however, this did not impact our SEM analysis which used severity scores. Our mean imputation of missing HDQ scores was a limitation that hence may have resulted in an overestimation of the precision of scores [
60,
61]. Out of the 941 cases included in the analysis, 908 (96%) had complete HDQ data. We used mean imputation at the time of HDQ scoring to recover the subscale HDQ scores prior to the SEM analysis to bring the dataset from 908 complete case responses (96%) to 941. Severity items we used to compute the subscale scores that were used in the analysis had few missing responses, ranging from 1 missing response (0.1%) for HDQ51 (I have trouble climbing stairs) to 33 missing responses (3.5%) for HDQ19 (I have problems with my hearing). Nevertheless, our mean imputation remains a limitation; future SEM work should consider full implementation maximum likelihood (FIML) methods to ‘preserve’ characteristics of the data, so that parameter estimates possess minimal bias, meaning they are derived from a mean and variance as close as possible to that of the true population [
60]. Next, interpretations of the strengths of standardized path coefficients may vary. Our a priori interpretations of the strengths of standardized path coefficients as predictors of disability in this study were arbitrary, and consistent with values used in previous latent variable modeling of disability in the context of HIV [
18]. Finally, because of the cross-sectional nature of our analysis, we were not able to draw inferences regarding causality. We hypothesized our direct relationships in our structural model based on our previous work [
18] and supported by literature that suggests physical health predicts mental health [
62]. However, in reality the relationships between these dimensions are likely more complex. Exploration of disability using longitudinal analytical approaches may help to determine causation and the impact of interventions in addressing disability over time.
Acknowledgements
We acknowledge contributions of the Knowledge Users, Collaborator Organizations and Recruitment Network Organizations. We thank the HIV Health and Rehabilitation Survey (HHRS) study participants.
We thank the following members of the HHRS team who were integrally involved in refining the survey instrument, recruiting participants, interpreting findings, and knowledge translation efforts including: Murray Jose-Boerbridge (Toronto People With AIDS (PWA) Foundation, Toronto, Ontario, Canada), Patrick McDougall (Dr. Peter AIDS Foundation, Vancouver, British Columbia, Canada), Tammy Reimer (Nine Circles Community Health Centre, Winnipeg, Manitoba, Canada), Wayne Campbell (Positive Living Society of British Columbia, Vancouver, British Columbia, Canada), Liz Harrop-Archibald (AIDS Coalition of Nova Scotia (ACNS), Halifax, Nova Scotia, Canada), and William Chegwidden (National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, London, United Kingdom).
We thank the following community organizations for their collaboration and support of the HHRS Study: Realize, formerly the Canadian Working Group on HIV and Rehabilitation (CWGHR), Casey House (Toronto), Toronto People With AIDS Foundation (Toronto PWA), AIDS Committee of Durham Region, AIDS Niagara, HIV Care Program Windsor Regional Hospital, AIDS Committee of Toronto (ACT), Prisoners with HIV/AIDS Support Action Network (PASAN), Dr. Kovacs’ Office-Maple Leaf Medical Centre (Toronto), The AIDS Network (Hamilton), AIDS Committee of Ottawa (Ottawa), Teresa Group (Toronto), HIV/AIDS Regional Services (Kingston), AIDS Committee of Windsor, Dr. Peter AIDS Foundation (Vancouver), Positive Living Society of British Columbia, HIV Edmonton, Positive Women’s Network (Vancouver), Pacific AIDS Network (Vancouver), Alberta Community Council on HIV (Edmonton), Nine Circles Community Health Centre (Winnipeg), AIDS Community Care Montreal (ACCM), Northern AIDS Connection Society, AIDS Committee of Newfoundland and Labrador, AIDS Saint John, and AIDS New Brunswick (Fredericton). We thank Ayesha Nayar and Nkem Iku (Research Coordinators, University of Toronto) for their contributions to the study.
The HIV Health and Rehabilitation Survey (HHRS) Team includes a group of researchers, knowledge users, and collaborators in Canada and the United Kingdom.
HHRS Team Researchers: Kelly K. O’Brien (University of Toronto), Patty Solomon (McMaster University), Francisco Ibáñez-Carrasco (Ontario HIV Treatment Network / St. Michael’s Hospital), Catherine Worthington (University of Victoria), Jacqueline Gahagan (Dalhousie University), Stephanie Nixon (University of Toronto), Steven Hanna (McMaster University), Brenda Merritt (Dalhousie University).
HHRS Team Knowledge Users: Tammy Yates, Stephen Tattle, Elisse Zack (Realize, formerly known as the Canadian Working Group on HIV and Rehabilitation (CWGHR)), Will Chegwidden (National Hospital for Neurology and Neurosurgery, University College Hospitals), Patriic Gayle (Gay Men's Health Collective, Three Flying Piglets), Larry Baxter (Community Member), Greg Robinson (Community Member), Tara Carnochan, Dawn James, and Tammy Reimer (Nine Circles Community Health Centre), Rosalind Baltzer Turje and Patrick McDougall (Dr. Peter AIDS Foundation).
HHRS Team Collaborators: Toronto PWA Foundation (Murray Jose-Boerbridge), Casey House (Soo Chan Carusone), Positive Living Society of British Columbia (Wayne Campbell and Adam Reibin), AIDS Coalition of Nova Scotia (Liz Harrop-Archibald and Laura Toole).
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.