Frailty in people with rheumatoid arthritis: a systematic review of observational studies

Psychometric Properties of Frailty Instruments in Adults With Rheumatoid Arthritis: A Systematic Review

OBJECTIVE

Examine psychometric properties of frailty instruments used in adults with rheumatoid arthritis (RA) to inform selection of frailty instruments for clinical and research use.

METHODS

A systematic review was registered in PROSPERO. Studies measuring frailty in adults with RA published before May 25, 2022, were searched in six electronic databases. Level of evidence of psychometric properties were synthesized and graded for each frailty instrument using Consensus-Based Standards for the Selection of Health Measurement Instruments methodology.

RESULTS

There were 22 articles included in the review, and psychometric properties of 16 frailty instruments were examined. RA cohorts were predominantly female with moderate RA disease activity, mean age was 60.1 years, and frailty prevalence ranged widely from 10% to 85%. Construct validity was the only psychometric property routinely examined for frailty instruments in RA, and nearly all (14/16) performed favorably in this domain. Frailty correlated most frequently with older age, higher RA disease activity, and worse physical function. Internal consistency, measurement error, and content validity were examined infrequently. Reliability and responsiveness data were not reported. Six frailty instruments were rated highest in adults with RA: three adaptations of Fried's Criteria, 32-Item and 45-Item Frailty Indexes, and the Comprehensive Rheumatologic Assessment of Frailty.

CONCLUSION

Six frailty instruments possessed the highest-rated psychometric properties in RA. These instruments demonstrated construct validity of frailty with important outcomes in RA. Frailty assessment shows promise to inform risk stratification in RA, but studies are needed to evaluate reliability, responsiveness, and validity to support accuracy of frailty measurement in adults with RA who may have disease-related features that differentially impact outcomes.

Frailty in rheumatoidrmdopen-2021-002111 arthritis and its relationship with disease activity, hospitalisation and mortality: a longitudinal analysis of the Scottish Early Rheumatoid Arthritis cohort and UK Biobank

OBJECTIVE

To assess the prevalence of frailty in rheumatoid arthritis (RA) and its association with baseline and longitudinal disease activity, all-cause mortality and hospitalisation.

PARTICIPANTS

People with RA identified from the Scottish Early Rheumatoid Arthritis (SERA) inception cohort (newly diagnosed, mean age 58.2 years) and UK Biobank (established disease identified using diagnostic codes, mean age 59 years). Frailty was quantified using the frailty index (both datasets) and frailty phenotype (UK Biobank only). Disease activity was assessed using Disease Activity Score in 28 joints (DAS28) in SERA. Associations between baseline frailty and all-cause mortality and hospitalisation was estimated after adjusting for age, sex, socioeconomic status, smoking and alcohol, plus DAS28 in SERA.

RESULTS

Based on the frailty index, frailty was common in SERA (12% moderate, 0.2% severe) and UK Biobank (20% moderate, 3% severe). In UK Biobank, 23% were frail using frailty phenotype. Frailty index was associated with DAS28 in SERA, as well as age and female sex in both cohorts. In SERA, as DAS28 lessened over time with treatment, mean frailty index also decreased. The frailty index was associated with all-cause mortality (HR moderate/severe frailty vs robust 4.14 (95% CI 1.49 to 11.51) SERA, 1.68 (95% CI 1.26 to 2.13) UK Biobank) and unscheduled hospitalisation (incidence rate ratio 2.27 (95% CI 1.45 to 3.57) SERA 2.74 (95% CI 2.29 to 3.29) UK Biobank). In UK Biobank, frailty phenotype also associated with mortality and hospitalisation.

CONCLUSION

Frailty is common in early and established RA and associated with hospitalisation and mortality. Frailty in RA is dynamic and, for some, may be ameliorated through controlling disease activity in early disease.