Physical activity, exercise, and inflammatory markers in older adults: findings from the Health, Aging and Body Composition Study.
OBJECTIVE
To examine the association between physical activity and inflammatory markers, with consideration for body fatness and antioxidant use.


METHODS
Cross-sectional study, using baseline data from the Health, Aging and Body Composition Study.


METHODS
Metropolitan areas surrounding Pittsburgh, Pennsylvania, and Memphis, Tennessee.


METHODS
Black and white, well-functioning men and women (N=3,075), aged 70 to 79.


METHODS
Interviewer-administered questionnaires of previous-week household, walking, exercise, and occupational/volunteer physical activities. Analysis of covariance was used to examine the association between activity level and serum C-reactive protein (CRP), interleukin-6 (IL-6), and plasma tumor necrosis factor alpha (TNFalpha) with covariate adjustment. Antioxidant supplement use (multivitamin, vitamins E or C, beta carotene) was evaluated as an effect modifier of the association.


RESULTS
Higher levels of exercise were associated with lower levels of CRP (P<.01), IL-6 (P<.001), and TNFalpha (P=.02) (e.g., CRP=1.95 mg/L for no exercise and 1.72 for >180 min/wk). Adjustment for body fatness attenuated the associations somewhat. Use of antioxidant supplements modified the CRP (P(interaction)=.01) and IL-6 (P(interaction)=.08) associations such that concentrations were low in those taking supplements (e.g., CRP=1.79-1.84 across exercise levels) and higher in nonsupplement users who did no exercise (2.03) than in those who did the most (1.72). Among nonexercisers, higher levels of other physical activity were related to lower levels of CRP (P<.01) and IL-6 (P=.02) but not TNFalpha (P=.36), even after accounting for body fat.


CONCLUSIONS
Inflammatory markers are lower in older adults with higher levels of exercise and nonexercise activity and in antioxidant supplement users regardless of exercise level.
Colbert
Lisa H
LH
Laboratory of Epidemiology, Demography, and Biometry, National Institute on Aging, Bethesda, Maryland, USA. lhcolbert@education.wisc.edu
Visser
Marjolein
M
Simonsick
Eleanor M
EM
Tracy
Russell P
RP
Newman
Anne B
AB
Kritchevsky
Stephen B
SB
Pahor
Marco
M
Taaffe
Dennis R
DR
Brach
Jennifer
J
Rubin
Susan
S
Harris
Tamara B
TB
D000368:Aged; D000375:Aging / Q000502:physiology*; D000975:Antioxidants / Q000008:administration & dosage; D015415:Biomarkers / Q000097:blood*; D001823:Body Composition; D002097:C-Reactive Protein / Q000378:metabolism; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D015444:Exercise / Q000502:physiology*; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D007249:Inflammation / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D016018:Least-Squares Analysis; D008297:Male; D010414:Pennsylvania; D010809:Physical Fitness; D011795:Surveys and Questionnaires; D013714:Tennessee; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D000975:Antioxidants; D015415:Biomarkers; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein