Muscular and plasma markers for early identification of frailty and sarcopenia states in people with HIV: results from the IMAGING study

Background Healthcare needs of older people with HIV (PWH) are changing given the higher incidence and earlier onset of age-related conditions compared to people without HIV (PWoH). This emphasizes a need for novel prognostic markers that allow identification of earlier stages of functional deterioration and prevent its advancement. Methods With this aim, we compared muscular imaging markers (whole body magnetic resonance imaging) and plasma biomarkers (irisin, myostatin, coenzyme Q10) between PWH (n = 50) and PWoH (n = 25) aged 50 or older, and their associations with clinical conditions. Spearman's rank correlation coefficient was estimated and presented in correlation matrices for the most relevant groups of study variables with intramuscular fat fraction and plasma biomarkers. The distribution of plasma biomarkers and intramuscular fat fraction values was presented graphically in boxplots as a function of the functional test category. The Wilcoxon rank sum test was performed for comparisons and p-values are presented in tables. Raw and adjusted logistic models were fitted and the estimated odds ratios are presented in tables. Adjusted variables were age, sex, and HIV status group. Results PWH exhibited greater deterioration, including lower autonomy, higher rates of pre-frailty/frailty and malnutrition, and reduced bone mineral density. Mild to moderate dependency (Barthel) was observed only in PWH (18.4%), with 50% of PWH at risk of dependency (Barber) compared to 25% in PWoH. Pre-frailty (Fried) was more prevalent in PWH (46%) than PWoH (28%), and frailty was exclusive to PWH (14%). PWH also had higher plasma myostatin and lower irisin levels. Lower intramuscular fat content was associated with malnutrition and dependency, while total intramuscular fat was positively correlated with time living with HIV and negatively with CD4 T cell count. Higher coenzyme Q10 levels were seen in states of poorer health, particularly frailty (Fried, SPPB), while higher irisin levels were observed together with frailty (Fried) and dependency (Barthel, Barber). For all adjusted models, HIV status strongly influenced Fried, Barthel, SPPB functional scores. Conclusions These findings underscore the need for further assessment of these biomarkers for their diagnostic and predictive potential in aging-related conditions such as frailty in PWH.