Is there an association between inflammatory markers and lower physical performance in older adults?

BACKGROUND: Maintenance of physical performance is essential for achievement of healthy aging. A few studies have explored the association between inflammatory markers and physical performance in older adults with inconclusive results. Our aim was to analyze the association of tumor necrosis factor-alpha (TNF-α), Interleukin-10 (IL-10), and C-reactive protein (CRP) with physical performance in a sample of older adults in rural settings of Mexico. METHODS: Our study comprised 307 community-dwelling older men and women who participated in the third wave of the Rural Frailty Study. We assessed the physical performance with the Short Physical Performance Battery (SPPB) and classified older adults as low performance if SPPB scored ≤8. Inflammatory markers were ascertained using serum by immunodetection methods. Logistic regression models were used to estimate the associations between inflammatory markers and physical performance. RESULTS: In comparison with the normal physical performance group, low physical performance individuals mainly were female (P <  0.01), older (P <  0.01), more illiterate (P = 0.02), more hypertensive (P < 0.01), fewer smokers (P = 0.02), and had higher CRP levels (P < 0.01). The logistic model results showed a significant association between the 3rd tertile of CRP and low physical performance (OR = 2.23; P = 0.03). IL-10 and TNF-α levels did not show a significant association. CONCLUSIONS: The results of this study were mixed, with a significant association of physical performance with higher CRP levels but nonsignificant with IL-10 and TNF-α. Further studies with improved designs are needed by incorporating a broader set of inflammatory markers.

Longitudinal association of sarcopenia and mild cognitive impairment among older Mexican adults.

BACKGROUND: Recent evidence from cross-sectional and longitudinal studies supports the hypothesis that sarcopenia is associated with worsening cognitive function. However, primary evidence largely comes from high-income countries, whereas in low- and middle-income countries, this association has been underexplored. This study aimed to estimate the longitudinal association between sarcopenia and mild cognitive impairment in a sample of older Mexican adults. METHODS: Data come from the three waves of the World Health Organization (WHO) Study on Global AGEing and Adult Health (SAGE) in Mexico (2009, 2014, 2017). Four hundred ninety-six older adults, aged ≥50, were included. Sarcopenia was defined as having low muscle quantity and either/both slow gait speed and weak handgrip strength. Mild cognitive impairment was determined based on the recommendations of the National Institute on Aging-Alzheimer's Association. Cognitive function was evaluated by a composite cognitive score of five different cognitive tests: immediate and delayed recall, forward and backward digit span and semantic verbal fluency. Three-level mixed-effects models (logistic and linear) were used to estimate the longitudinal associations between sarcopenia, mild cognitive impairment and cognitive function. RESULTS: The prevalence of mild cognitive impairment (8.9%, 12.9%, 16.0%) and sarcopenia (10.5%, 20.7%, 23.3%) showed a significant temporal increase for Waves 1, 2 and 3 (P-value < 0.01, respectively). The presence of sarcopenia was significantly associated with mild cognitive impairment (OR = 1.74; CI95% 1.02, 2.96; P = 0.04) and worse cognitive function (ß = -0.57; CI95% -0.93, -0.21; P < 0.01). We observed significant associations between sarcopenia and immediate verbal recall (ß = -0.14; CI95% -0.28, -0.01; P = 0.04), delayed verbal recall (ß = -0.12; CI95% -0.23, -0.01; P = 0.03) and semantic verbal fluency (ß = -0.17; CI95% -0.28, -0.05; P = 0.01). The prevalence of mild cognitive impairment increased at an annual rate of 0.8% for non-sarcopenic older adults, but nearly 1.5% for sarcopenic adults. CONCLUSIONS: Significant longitudinal associations were observed between sarcopenia, mild cognitive impairment and cognitive function among older Mexican adults. Public health strategies, including policy research and clinical interventions, must be implemented in low- and middle-income countries in order to reduce or delay the onset of sarcopenia and thus improve population-level cognitive health among older adults.