Enhancing Intrinsic Capacity and Related Biomarkers in Community-Dwelling Multimorbid Older Adults Through Integrated Multidomain Interventions: Ancillary Findings From the Taiwan Integrated Geriatric (TIGER) Trial

Objective: This study aimed to evaluate the efficacy of integrated multidomain interventions and primary health care on intrinsic capacity (IC) and related biomarkers. Design: An ancillary analysis from the Taiwan Integrated Geriatric Care (TIGER) study: a randomized controlled trial. Setting and Participants: A total of 398 community-dwelling older adults aged ≥65 years with ≥3 chronic conditions. Methods: Participants were randomized into the 12-month pragmatic multidomain intervention or usual care groups. The primary outcome was the change in IC and its subdomains (locomotion, cognition, vitality, psychological, and sensory) at baseline and 3-, 6-, 9-, and 12-month follow-ups. Generalized linear mixed models were used to evaluate the multidomain intervention effects on these changes. Results: The intervention arm had greater improvement in IC than the usual care arm (overall difference 1.5; 95% CI 0.5–2.5; P = .005), mainly from subdomains of locomotion (overall difference 1.4; 95% CI 0.5–2.4; P = .004) and cognition (2.9; 95% CI 2.1–3.7; P < .001). Changes in neutrophil-to-lymphocyte ratio (NLR −2.4; 95% CI −3.9 to −0.8, P = .003), serum levels of albumin (35.1; 95% CI 23.1–47.2; P < .001), dehydroepiandrosterone sulfate (DHEA-S 2.8; 95% CI 1.9–3.8; P < .001), free androgen index (FAI 1.5; 95% CI 1.1–1.9; P < .001), and vitamin D (4.0; 95% CI 2.0–6.1; P < .001) were associated with changes in IC over time. Conclusions and Implications: The incorporation of multidomain interventions into primary health care significantly enhanced IC over the 12-month program. Changes in NLR, FAI, and serum levels of albumin, DHEA-S, vitamin D were associated with changes in IC over time. Trial registration: ClinicalTrials.gov Identifier: NCT03528005.