Lipoprotein peroxidation and mobility limitation: results from the Health, Aging, and Body Composition Study.
BACKGROUND
Oxidative damage plays an important role in leading to major health-related events. The aim of this study was to assess the predictive value of a lipoprotein peroxidation marker, oxidized low-density lipoprotein (oxLDL) for incident mobility limitation (ML).


METHODS
Data are from 2985 well-functioning elders enrolled in the Health ABC study (median follow-up, 4.1 years). All oxLDL levels were measured at the baseline assessment. The oxLDL/LDL cholesterol (LDL-C) ratio (log value) was used as a measure of lipoprotein peroxidation. Mobility limitation was defined by 2 consecutive semiannual reports of any difficulty either walking 1/4 mile or climbing up 10 steps without resting. Severe ML was defined by 2 consecutive reports of great difficulty or inability to do the same tasks. Cox proportional hazards models were performed to assess hazard ratios (HRs) and 95% confidence intervals (CIs).


RESULTS
The mean (SD) age of the sample was 74.2 (2.9) years. After adjustment for potential confounders (sociodemographic factors, smoking, physical activity, body mass index, clinical conditions, biological markers, and medications), the relationship between the oxLDL/LDL-C ratio and disability events was statistically significant (per log-unit difference in the oxLDL/LDL-C ratio) (for ML: HR, 1.22; 95% CI, 1.06-1.41; for severe ML: HR, 1.43; 95% CI, 1.15-1.79). Consistent results were found when interleukin 6 level was included as a covariate in the adjusted models (ML: HR, 1.13; 95% CI, 0.98-1.31; severe ML: HR, 1.31; 95% CI, 1.05-1.64). No significant sex, race, interleukin 6 level, or clinical conditions interaction was found with the oxLDL/LDL-C ratio and mobility disability.


CONCLUSIONS
Lipoprotein peroxidation predicts the onset of ML in older persons. The oxLDL predictive value for ML is partly explained by interleukin 6 levels.
Cesari
Matteo
M
Department of Aging and Geriatric Research, College of Medicine, Institute on Aging, University of Florida, Gainesville 32608, USA. mcesari@aging.ufl.edu
Kritchevsky
Stephen B
SB
Nicklas
Barbara J
BJ
Penninx
Brenda W H J
BW
Holvoet
Paul
P
Koh-Banerjee
Pauline
P
Cummings
Steven R
SR
Harris
Tamara B
TB
Newman
Anne B
AB
Pahor
Marco
M
D000368:Aged; D000375:Aging; D015415:Biomarkers; D001823:Body Composition; D008078:Cholesterol, LDL / Q000097:blood; D015331:Cohort Studies; D005260:Female; D015577:Geriatric Assessment; D006304:Health Status; D006801:Humans; D015227:Lipid Peroxidation; D008077:Lipoproteins, LDL / Q000097:blood*; D008124:Locomotion; D008297:Male; D011446:Prospective Studies; D016059:Range of Motion, Articular
D015415:Biomarkers; D008078:Cholesterol, LDL; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein