Do myokines influence the associations between sarcopenia-related parameters and cognitive function in community-dwelling older adults: exploratory results from the ENHANce study.

BACKGROUND

Studies have shown that sarcopenia and its related parameters are associated with cognition. Preclinical evidence suggests that myokines, such as irisin, Brain-Derived Neurotrophic Factor(BDNF), myostatin and Insulin-like Growth Factor-1(IGF-1) might explain this relationship. This study aimed to explore the associations between sarcopenia-related parameters and cognition, and whether myokines influence this association.

METHODS

Exploratory, cross-sectional analysis of data from the Exercise and Nutrition for Healthy AgeiNg (ENHANce,NCT03649698) study. Participants were older adults(≥65 years) with EWGSOP2-defined sarcopenia. Cognitive functioning was assessed by Mini-Mental State Examination(MMSE), Repeatable Battery for the Assessment of Neuropsychological Status(RBANS), Trail Making Test A&B(TMT), Stroop and Maze Test. Sarcopenia-related parameters were measured: Handgrip Strength, Chair Stand Test, appendicular Lean Mass(aLM), Gait Speed (GS) and Short Physical Performance Battery(SPPB). Serum myokines(IGF-1, irisin, myostatin, BDNF) were determined through ELISA. Associations between cognition and sarcopenia-related parameters were analyzed using multivariable regression, adjusting for potential confounders including myokines.

RESULTS

Fifty-eight participants were included in this analysis (76.2 ± 6.7 years, ♀:65.5%). After adjustment for age, sex, body mass index, aLM was associated with MMSE(β = 0.193,p = 0.012), RBANS Total(β = 0.196,p = 0.007) and RBANS Attention(β = 0.215,p = 0.002), CST was associated with RBANS Language(β = -0.314,p = 0.030), SPPB was associated with Maze time(β = -0.364,p = 0.004) and TMT-B (β = -0.333,p = 0.013) and GS was associated with TMT-A(β = -0.324,p = 0.045). After adjustments for BDNF& IGF-1, the association between GS and TMT-A became non-significant. Irisin and myostatin did not influence the sarcopenia-cognition associations.

CONCLUSION

Sarcopenia-related parameters are associated with global and specific cognitive domains. BDNF may, partially, explain the association between muscle mass and MMSE. Additional research with larger sample size is needed to confirm these findings.