TY - JOUR
T1 - White blood cell counts, insulinlike growth factor-1 levels, and frailty in community-dwelling older women
AU - Leng, Sean X.
AU - Hung, Will
AU - Cappola, Anne R.
AU - Yu, Qilu
AU - Xue, Qian Li
AU - Fried, Linda P.
PY - 2009/4
Y1 - 2009/4
N2 - Background. Elevated white blood cell (WBC) counts and decreased insulin-like growth factor-1 (IGF-1) levels are individually associated with frailty in older adults. WBC subpopulations are known to produce IGF-1 and express IGF-1 receptors in vitro. However, in vivo relationships between WBC and IGF-1 and their joint contribution to frailty have not been investigated. Methods. Baseline data from 696 community-dwelling older women in the Women's Health and Aging Study I were included in this cross-sectional analysis. Multivariate linear regression analysis was performed to assess the relationship between WBC counts and IGF-1 levels. Odds ratios (ORs) for frailty were evaluated across tertiles of WBC counts and IGF-1 levels, adjusting for age, race, education, body mass index, and smoking. Results. WBC counts correlated with IGF-1 levels (Spearman coefficient: .10, p < .01). Compared with participants in the low WBC and high IGF-1 tertiles (reference group), those in the low WBC and low IGF-1 tertiles had OR of 2.33 for frailty (95% confidence interval [CI]: 1.04-3.65, p < .05), those in the high WBC and high IGF-1 tertiles had OR of 3.86 (95% CI: 1.13-4.07, p < .01), and those in the high WBC and low IGF-1 tertiles had OR of 3.61 (95% CI: 1.64-4.97, p < .01), adjusting for covariates. Conclusions. These findings demonstrate in vivo correlation between WBC and IGF-1. They suggest U-shaped joint associations of WBC and IGF-1 with frailty, with the strongest association at adverse levels of both. They also provide a basis for further investigation into the complex immune-endocrine dysregulations in frailty.
AB - Background. Elevated white blood cell (WBC) counts and decreased insulin-like growth factor-1 (IGF-1) levels are individually associated with frailty in older adults. WBC subpopulations are known to produce IGF-1 and express IGF-1 receptors in vitro. However, in vivo relationships between WBC and IGF-1 and their joint contribution to frailty have not been investigated. Methods. Baseline data from 696 community-dwelling older women in the Women's Health and Aging Study I were included in this cross-sectional analysis. Multivariate linear regression analysis was performed to assess the relationship between WBC counts and IGF-1 levels. Odds ratios (ORs) for frailty were evaluated across tertiles of WBC counts and IGF-1 levels, adjusting for age, race, education, body mass index, and smoking. Results. WBC counts correlated with IGF-1 levels (Spearman coefficient: .10, p < .01). Compared with participants in the low WBC and high IGF-1 tertiles (reference group), those in the low WBC and low IGF-1 tertiles had OR of 2.33 for frailty (95% confidence interval [CI]: 1.04-3.65, p < .05), those in the high WBC and high IGF-1 tertiles had OR of 3.86 (95% CI: 1.13-4.07, p < .01), and those in the high WBC and low IGF-1 tertiles had OR of 3.61 (95% CI: 1.64-4.97, p < .01), adjusting for covariates. Conclusions. These findings demonstrate in vivo correlation between WBC and IGF-1. They suggest U-shaped joint associations of WBC and IGF-1 with frailty, with the strongest association at adverse levels of both. They also provide a basis for further investigation into the complex immune-endocrine dysregulations in frailty.
KW - Frailty
KW - IGF
KW - WBC
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U2 - 10.1093/gerona/gln047
DO - 10.1093/gerona/gln047
M3 - Article
C2 - 19251912
AN - SCOPUS:64849089588
SN - 1079-5006
VL - 64
SP - 499
EP - 502
JO - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
JF - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
IS - 4
ER -