TY - JOUR
T1 - Serum 25-hydroxyvitamin D, plasma klotho, and lower-extremity physical performance among older adults
T2 - Findings from the InCHIANTI Study
AU - Shardell, Michelle
AU - Semba, Richard D.
AU - Kalyani, Rita R.
AU - Hicks, Gregory E.
AU - Bandinelli, Stefania
AU - Ferrucci, Luigi
N1 - Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2015/9
Y1 - 2015/9
N2 - Background. The hormone klotho is encoded by aging-suppressor gene klotho and has multiple roles, including regulating mineral (calcium and phosphate) homeostasis. Vitamin D also regulates mineral homeostasis and upregulates klotho expression. Klotho positively relates to longevity, upper-extremity strength, and reduced disability in older adults; however, it is unknown whether circulating klotho relates to lower-extremity physical performance or whether the relation of vitamin D with physical performance is mediated by klotho. Methods. Klotho and 25-hydroxyvitamin D [25(OH)D] were measured in 860 participants aged ≥ 55 years in Invecchiare in Chianti, "Aging in Chianti" (InCHIANTI), a prospective cohort study comprising Italian adults. Lower-extremity physical performance was measured using the Short Physical Performance Battery, a summary score of balance, chair stand ability, and walking speed. Weighted estimating equations related plasma klotho and serum 25(OH)D concentrations measured at one visit to Short Physical Performance Battery measured longitudinally at multiple visits. Results. Each additional natural log of klotho (pg/mL) was associated with 0.47 higher average Short Physical Performance Battery scores (95% confdence interval: 0.08 to 0.86, p value = .02) after adjustment for covariates, including 25(OH)D. Each natural log of 25(OH)D (ng/mL) was associated with 0.61 higher average Short Physical Performance Battery scores (95% confdence interval: 0.35 to 0.88, p value < .001) after adjustment for covariates, a result that changed little after adjustment for klotho. Conclusions. Plasma klotho and 25(OH)D both positively related to lower-extremity physical performance. However, the findings did not support the hypothesis that klotho mediates the relation of 25(OH)D with physical performance.
AB - Background. The hormone klotho is encoded by aging-suppressor gene klotho and has multiple roles, including regulating mineral (calcium and phosphate) homeostasis. Vitamin D also regulates mineral homeostasis and upregulates klotho expression. Klotho positively relates to longevity, upper-extremity strength, and reduced disability in older adults; however, it is unknown whether circulating klotho relates to lower-extremity physical performance or whether the relation of vitamin D with physical performance is mediated by klotho. Methods. Klotho and 25-hydroxyvitamin D [25(OH)D] were measured in 860 participants aged ≥ 55 years in Invecchiare in Chianti, "Aging in Chianti" (InCHIANTI), a prospective cohort study comprising Italian adults. Lower-extremity physical performance was measured using the Short Physical Performance Battery, a summary score of balance, chair stand ability, and walking speed. Weighted estimating equations related plasma klotho and serum 25(OH)D concentrations measured at one visit to Short Physical Performance Battery measured longitudinally at multiple visits. Results. Each additional natural log of klotho (pg/mL) was associated with 0.47 higher average Short Physical Performance Battery scores (95% confdence interval: 0.08 to 0.86, p value = .02) after adjustment for covariates, including 25(OH)D. Each natural log of 25(OH)D (ng/mL) was associated with 0.61 higher average Short Physical Performance Battery scores (95% confdence interval: 0.35 to 0.88, p value < .001) after adjustment for covariates, a result that changed little after adjustment for klotho. Conclusions. Plasma klotho and 25(OH)D both positively related to lower-extremity physical performance. However, the findings did not support the hypothesis that klotho mediates the relation of 25(OH)D with physical performance.
KW - Biomarkers
KW - Epidemiology
KW - Metabolism
KW - Physical function
KW - Physical performance
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U2 - 10.1093/gerona/glv017
DO - 10.1093/gerona/glv017
M3 - Article
C2 - 25748032
AN - SCOPUS:84943328096
SN - 1079-5006
VL - 70
SP - 1156
EP - 1162
JO - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
JF - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
IS - 9
ER -