Geriatric syndromes: new frontiers in HIV and sarcopenia

Abstract

: HIV infection, in many circumstances, can now be managed as a chronic disease due to the marked increase in life expectancy since the introduction of combination antiretroviral therapy (ART). As the patients who first had access to combination ART age into their 50s and 60s, the effects of chronic HIV infection on health have become an important research focus in HIV infection. People living with HIV appear to exhibit an earlier occurrence of some aging-related conditions compared to people without HIV, in part due to higher rates of comorbidities, high-risk behaviors (e.g. smoking, substance use), chronic immune activation, inflammation, and ART-specific factors. Some studies have even suggested an earlier-than-expected appearance of the 'geriatric syndromes,' which are complex medical syndromes of older adults that are associated with morbidity and mortality. The geriatric syndromes include a wide variety of disease processes ranging from incontinence and dementia to impairments in physical function. This review will focus on one geriatric syndrome, sarcopenia, in older HIV-infected populations, and its relation to other aging syndromes, including frailty and falls. The contribution of HIV itself, ART exposure, and specific comorbidities, and the importance of early recognition and prevention of these aging syndromes will be highlighted.

Figure 1

Relationship of sarcopenia, frailty, falls, and functional limitation.

Figure 2

Theoretical trajectories of differing rates of development of geriatric syndromes and further decline in physical function among older, HIV-infected adults, stratified by baseline physical function. The red line represents the trajectory of an individual beginning with a lower level of muscle mass or physical function. The individual undergoes multiple insults with age due to illness, hospitalizations, falls, or other stressors. Theoretically, this individual is unable to completely recover following these episodes and quickly passes a threshold of clinical weakness, onset of a geriatric syndrome, and ultimately death. In an individual starting at a higher level of physical function, repeated insults may either fail to significantly impede physical function (green line), or impact function but with a longer time to clinically apparent weakness and onset of a geriatric syndrome (blue line).

Figure 3

^{[114, 115]} ¥: The HIV-specific Pillars of Aging are processes common to aging with or without HIV infection, and the processes that may be unique to or exaggerated in aging with HIV infection (highlighted). *Residual HIV viremia, co-infections and gut microbial translocation included under the larger umbrella of chronic inflammation and immune activation. ** Shorter leukocyte-telomere-length (a marker of aging) has been noted in HIV infection. ***Detailed in the “sarcopenia” section of this review. ¥ This figure was adapted from figure 1 in the reference and with permission of the authors and publisher, license number 4032010426699 and 4026641471571, respectively.