Determinants of health status in older patients with transthyretin cardiac amyloidosis: a prospective cohort study

Background: Whether, and to what extent, frailty and other geriatric domains are linked to health status in patients with transthyretin cardiac amyloidosis (ATTR-CA) is unknown. Aims: To determine the association of frailty with health status [defined by the Kansas City Cardiomyopathy Questionnaire (KCCQ)] in patients with ATTR-CA. Methods: Consecutive ATTR-CA patients undergoing cardiovascular assessment at a tertiary care clinic from September 2021 to September 2023 were invited to participate. KCCQ, frailty and social environment were recorded. Frailty was assessed using the modified Frailty Index (mFI), mapping 11 variables from the Canadian Study of Health and Aging (frailty ≥0.36). Results: Of 168 screened ATTR-CA patients, 138 [83% men, median age of 79 (75-84) years] were enrolled in the study. Median KCCQ was 66 (50-75). wtATTR-CA was the most prevalent form (N = 113, 81.9%). The most frequent cardiac variant was Ile68Leu (17/25 individuals with vATTR-CA). Twenty (14.5%) patients were considered frail, and prevalence of overt disability was 6.5%. At multivariable linear regression analysis, factors associated with worsening KCCQ were age at evaluation, the mFI, NYHA Class, and NAC Score. Gender, ATTR-CA type, phenotype, and LVEF were not associated with health status. Discussion: In older patients diagnosed with ATTR-CA, frailty, symptoms, and disease severity were associated with KCCQ. Conclusions: Functional status is a determinant of quality of life and health status in older individuals with a main diagnosis of ATTR-CA. Future research may provide more in-depth knowledge on the association of frailty in patients with ATTR-CA with respect to quality of life and prognosis.