Abstract and Introduction
Abstract
Objectives. To assess changes in locomotor function in HIV-infected patients and to evaluate the determinants of variations in lower limb muscle performance.
Design. Longitudinal study within the ANRS CO3 Aquitaine Cohort.
Methods. Standardized locomotor tests, including global functional capacity [6-min walk distance (6MWD)] and lower limb muscle performance tests [five times sit-to-stand (5STS) test], were performed in HIV-infected adults at baseline and 2-year follow-up. Evolution of performances and determinants of 5STS time were studied in linear mixed-effects models.
Results. At baseline (354 patients, 90% on antiretroviral treatment), median 5STS time was 9.8 s and 6MWD 549 m. Poorer performances were associated with falls, reported by 12% of 178 patients at follow-up. Estimated mean deterioration was +0.24 s/year (P < 10−2) for 5STS time and -11 m/year (P < 10−4) for 6MWD. In multivariable analyses, older age was associated with worse baseline 5STS time (+0.47 s/10-year age increase; P = 10−3), but not with further deterioration. Deterioration was greater in prior injecting drug users compared to others (difference in slope +0.62 s/year; P = 0.04). 5STS time at any time point was worse in patients with history of cerebral AIDS conditions (+2.47 s; P < 10−3) and diabetes (+0.95 s; P = 0.02) than in others. No significant associations were found for antiretroviral treatment type, viral load or CD4+ cell count.
Conclusion. Compared to published data from healthy persons of similar age, baseline 5STS time and 6MWD were poorer in HIV-infected adults and associated with subsequent falls. Test performances deteriorated further over time. Age, diabetes, neurologic complications and injection drug use, rather than virologic factors, contribute to variations in lower limb muscle performance.
Introduction
In the general population, locomotor functions deteriorate with age and are associated with risk of falls and with limitations in daily activities.[1,2] A decrease in skeletal muscle strength is considered a key element of frailty and loss of autonomy.[3]
With an increasing life expectancy in HIV-infected patients,[4,5] age-related changes and comorbidities have become a concern as they occur relatively early in this population.[6] In previous cross-sectional analyses, we have reported that poor locomotor performance was highly prevalent in a comprehensive sample of middle-aged ambulatory HIV-infected patients, the majority of whom were on antiretroviral treatment (ART) and had well controlled viral load. Poor lower limb muscle function was detected in approximately one out of two patients and more frequent than would have been expected in the general population of similar age.[7] In accordance with these findings based on functional locomotor assessments, body composition studies by other groups have shown a high prevalence of low appendicular skeletal muscle mass in HIV-infected patients, equivalent to the prevalence observed in the general population 10–25 years older.[8,9] Moreover, a frailty phenotype is associated with falls,[10] and low muscle mass, limitations in physical function and frailty phenotype are determinants of poorer survival in HIV-infected patients.[11–14] Altogether, these results from recent clinical studies suggest that alterations of locomotor and muscle functions are of clinical relevance in the HIV-infected population in the era of combination ART. So far, no data are available in this population regarding the decline in locomotor function over time. Therefore, the objectives of the present study were to prospectively assess the changes in locomotor function in HIV-infected patients over time and to evaluate the determinants of variations in lower limb muscle performance.
AIDS. 2014;28(10):1441-1449. © 2014 Lippincott Williams & Wilkins
Lippincott Williams & Wilkins
