Author(s): PHILLIPS, N., CELIS-MORALES, C., GRAY, S., Institution: UNIVERSITY OF GLASGOW, Country: UNITED KINGDOM, Abstract-ID: 877

INTRODUCTION:
Sarcopenia, the age-related loss of muscle strength and mass, is a progressive and generalised skeletal muscle disorder that is associated with an increased risk of falls, fractures, physical disability, mortality, and worse quality of life. Both dietary protein and omega-3 fatty acids (n-3) have shown promise as potential interventions in the prevention and/or treatment of sarcopenia. The aim of this analysis was to determine the associations of protein and n-3 intake with sarcopenia sub-components and with all-cause mortality.
METHODS:
This study is a secondary data analysis from the UK Biobank in adults over 60. Muscle strength was assessed by grip strength, and muscle mass was assessed by bioelectrical impedance measured fat-free mass (FFM). All-cause mortality was determined from the date of death collected from death registers. A Cox proportional hazard analysis investigated the association between relative protein and n-3 intake and all-cause mortality. Linear regression analysis was performed to investigate the associations of relative protein and n-3 intake with grip strength and FFM. Participants were stratified into people without (0) or those with multi-morbidities (>2) for analyses. Data are presented as β (95% CI) unless stated otherwise.
RESULTS:
A 1 SD higher intake of n-3, equivalent to 0.85g/day, was associated with a 0.10 kg (95% CI: 0.00 - 0.21) and 0.24 kg (95% CI: 0.15 – 0.34) higher grip strength in those with, and without, multimorbidity respectively. Similarly, a 1 SD higher protein intake, equivalent to 0.28g/kg/day, was associated with a higher grip strength of 0.13 kg (95% CI: 0.01-0.24) and 0.22 kg (95% CI: 0.11- 0.33) in those with, and without, multimorbidity respectively. A 1 SD higher n-3 intake was associated with a 0.25 kg (95% CI: 0.20-0.30) and 0.24 kg (95% CI: 0.15-0.34) higher FFM in those with and without multimorbidity, respectively. No interaction effects between protein and n-3 intake were present for grip strength; however, a negative association (p<0.001) with FFM was seen in those with multimorbidity. A 1 SD higher protein intake was associated with a 0.23 kg (95% CI: 0.18-0.29) and 0.26 kg (95% CI: 0.21- 0.31) higher FFM in those with and without multimorbidity, respectively. In those without multimorbidity, a higher (>2.32g/day) n-3 intake was significantly associated with lower all-cause mortality (Hazard Ratio = 0.77 (95% CI: 0.63-0.93)) compared to the low (<1.64g/day) n-3 intake group.
CONCLUSION:
Dietary protein and n-3 intake are positively associated with grip strength and FFM, with little evidence of any interaction between the two nutrients. Only n-3 intake was associated with lower all-cause mortality.