Concomitant Lower Serum Albumin and Vitamin D Levels Are Associated with Decreased Objective Physical Performance among Japanese Community-Dwelling Elderly

Abstract

Background: Previous studies have shown that serum albumin or vitamin D is associated with physical performance. We hypothesized that older adults with concomitant lower serum albumin and vitamin D (25-hydroxyvitamin D, 25OHD) levels are associated with decreased physical performance compared to those with 1 or none of the 2 risk factors. Objective: To investigate the association of combined serum albumin and 25OHD levels with physical performance (muscle strength and balance capability) in community-dwelling elderly. Methods: A cross-sectional study in a community-based population in the province of Tokyo, Japan, was performed. For the study, 1,094 community-dwelling people aged 70 and older underwent an interview, anthropometric measurements, blood analysis and physical performance testing. The subjects were classified into 4 types by combining serum albumin and 25OHD levels: lower albumin only, lower vitamin D only, lower albumin and lower vitamin D, higher albumin and higher vitamin D. Results: Men with concomitant lower albumin and lower 25OHD levels had significantly decreased knee extension power, usual timed Up & Go and maximal timed Up & Go, even after adjusting for age and body mass index (BMI). In women, concomitant lower albumin and lower vitamin D was associated with significantly decreased handgrip strength and functional reach, even after adjusting for age and BMI. Subjects with combined lower albumin and lower vitamin D levels showed a significant decline in muscle strength and balance capability compared to higher albumin and higher vitamin D, even after adjusting for age, current drinking or smoking status, physical activity, history of chronic disease, basic activities of daily living, instrumental activities of daily living, BMI and bone mineral density. Conclusion: Concomitant lower serum albumin and lower vitamin D levels are associated with decreased muscle strength and balance capability in both men and women. These results suggest that serum albumin and 25OHD together may be an important target for strategies aiming to achieve a healthy life and prevent loss of independence in community-dwelling elderly.

Cross-sectional association between serum vitamin D concentration and walking speed measured at usual and fast pace among older women: The EPIDOS study

“…(10,(16)(17)(18)(19)(20)(21)(22) It has been shown that ambulation time over an 8-ft walkway correlated with higher serum 25(OH)D concentrations. (10,18) Gerdhem and colleagues (19) also have reported a positive significant linear correlation with usual walking speed in a cohort of 986 elderly women. However, this result was less reliable than previous studies because no adjustments for confounders were made.…”

“…However, this result was less reliable than previous studies because no adjustments for confounders were made. Additionally, Kwon and colleagues (18) showed that men with concomitantly low serum albumin and 25(OH)D concentrations had a low timed up and go score, even after adjusting for age and BMI. Finally, Suzuki and colleagues (16) recently highlighted a positive significant linear association with walking speed at a usual pace for either men or women in a larger cohort of 2957 Japanese subjects aged 65 years and older.…”

“…Second, previous studies used different cutoff values for abnormal serum 25(OH)D concentrations ranging from 10 to 30 ng/mL, (10,(16)(17)(18)(19)(20)(21)(22) which also may explain the divergences. From a historical point of view, normal vitamin D concentrations have been defined by the avoidance of adverse health consequences.…”

“…(16) Compared with muscle strength or balance performance, (5)(6)(7) fewer attempts have been made to explore the association between low chronic serum 25(OH)D concentrations and walking speed. (10,(16)(17)(18)(19)(20)(21)(22) A better understanding of this association is important to further develop interventional clinical studies to assess the effect of vitamin D supplementation on mobility and gait performance and related adverse health consequences. Previous studies showed conflicting results because some of them found a significant positive association, (10,(16)(17)(18)(19)(20) whereas others did not.…”

“…(10,(16)(17)(18)(19)(20)(21)(22) A better understanding of this association is important to further develop interventional clinical studies to assess the effect of vitamin D supplementation on mobility and gait performance and related adverse health consequences. Previous studies showed conflicting results because some of them found a significant positive association, (10,(16)(17)(18)(19)(20) whereas others did not. (21,22) These differences may be related, in part, to the type of walking speed measured.…”