The clinical utility of three frailty measures in identifying HIV-associated neurocognitive disorders

Abstract

Objective: Frailty measures vary widely and the optimal measure for predicting HIV-associated neurocognitive disorders (HAND) is unclear.

Design: A study was conducted to examine the clinical utility of three widely used frailty measures in identifying HIV-associated neurocognitive disorders.

Methods: The study involved 284 people with HIV (PWH) at least 50 years enrolled at UC San Diego's HIV Neurobehavioral Research Program. Frailty measurements included the Fried Phenotype, the Rockwood Frailty Index, and the Veterans Aging Cohort Study (VACS) Index. HAND was diagnosed according to Frascati criteria. ANOVAs examined differences in frailty severity across HAND conditions. ROC analyses evaluated sensitivity and specificity of each measure to detect symptomatic HAND [mild neurocognitive disorder (MND) and HIV-associated dementia (HAD)] from no HAND.

Results: Across all frailty measures, frailty was found to be higher in HAD compared with no HAND. For Fried and Rockwood (not VACS), frailty was significantly more severe in MND vs. no HAND and in HAD vs. ANI (asymptomatic neurocognitive impairment). For discriminating symptomatic HAND from no HAND, Fried was 37% sensitive and 92% specific, Rockwood was 85% sensitive and 43% specific, and VACS was 58% sensitive and 65% specific.

Conclusion: These findings demonstrate that Fried and Rockwood outperform VACS in predicting HAND. However, ROC analyses suggest none of the indices had adequate predictive validity in detecting HAND. The results indicate that the combined use of the Rockwood and Fried indices may be an appropriate alternative.

Figure 1.

Distribution of frailty observations in HIV sample based on frailty measurement criteria.

Figure 2.

Violin plots of frailty measures by HAND condition. Using the Fried Phenotype (panel A) and the Rockwood Frailty Index (panel B), individuals diagnosed with HAD had higher frailty scores than those with no HAND and ANI diagnoses, and those who were diagnosed with MND had higher frailty scores than those with no HAND. Using the VACS Index (panel C), individuals diagnosed with HAD had higher frailty scores than those with no HAND. Violin plots are presented as median frailty symptoms/indices (dashed lines) and quartiles (dotted lines). *p<.05, **p<.01, *** p<.001. Effect sizes are presented as Cohen’s d for parametric data and rank correlation (r) for non-parametric data.

Figure 3.

Sensitivity and specificity of each frailty measure to detect symptomatic from no HAND cases. A) The Fried Phenotype was 37% sensitive and 92% specific (optimal cutoff ≥3), the Rockwood Frailty index was 85% sensitive and 43% specific (optimal cutoff ≥.206), and the VACS was 58% sensitive and 65% specific (optimal cutoff ≥29). B) The associated area under the curve (AUC) for each frailty measure is also shown. Analyses were also conducted to detect symptomatic from asymptomatic (ANI) cases. A similar pattern of results were observed (results not presented in figure).