Construct and Criterion-Related Validity of the Clinical Frailty Scale in Persons With HIV

The co-occurrence of frailty and cognitive impairment in older (50+ years) persons with HIV (PWH) is common and increases the risk of poor outcomes. In HIV clinics, the most commonly used frailty measures are the frailty phenotype (FP), which requires measuring grip strength and gait speed to implement, and the frailty index (FI) based on comprehensive health data collected on patients. We examined construct and criterion-related validity (as it predicts cognition) of the Clinical Frailty Scale (CFS), a less resource-intensive approach for assessing frailty, in relation to these more commonly used frailty assessments (FP and FI).

A total of 143 older (age 50+) PWH (mean age 57 years; 88% male) seen at the Southern Alberta Clinic underwent both frailty screening with the FP, CFS, and FI and neuropsychological testing. Mixed-effects regressions examined the associations between frailty status and cognition.

Concordance with the FP was slightly superior for the CFS than the FI. The FP and CFS had similar associations with domain-specific cognitive performance with frail PWH performing worse than nonfrail individuals on tests requiring manual dexterity (Trail Making Part A and B; Symbol Digit; and Grooved Pegboard; P values <0.05). Neither were associated with executive function, learning, or memory performance. The FI was associated with worse fluency, fine motor skills (Grooved Pegboard), and Trail Making Part A.

The CFS is a simple screening tool with good construct and criterion-related validity. It was associated with a similar pattern of cognitive deficits as the FP. If confirmed and the associations are extended to other clinically significant characteristics and outcomes, the CFS can be considered as an alternative to the FP and FI in assessing frailty in older PWH.