The influence of obesity on calf blood flow and vascular reactivity in older adults.
OBJECTIVE
To determine whether differences in vascular reactivity existed among normal weight, overweight, and obese older men and women, and to examine the association between abdominal fat distribution and vascular reactivity.


METHODS
Eighty-seven individuals who were 60 years of age or older (age = 69 +/- 7 yrs; mean +/- SD) were grouped into normal weight (BMI < 25; n = 30), overweight (BMI > or = 25 and < 30; n = 28), or obese (BMI > or = 30; n = 29) categories. Calf blood flow (BF) was assessed by venous occlusion strain-gauge plethysmography at rest and post-occlusive reactive hyperemia.


RESULTS
Post-occlusive reactive hyperemia BF was lower (p = 0.038) in the obese group (5.55 +/- 4.67%/min) than in the normal weight group (8.34 +/- 3.89%/min). Additionally, change in BF from rest to post-occlusion in the obese group (1.93 +/- 2.58%/min) was lower (p = 0.001) than in the normal weight group (5.21 +/- 3.59%/min), as well as the percentage change (75 +/- 98% vs. 202 +/- 190%, p = 0.006, respectively). After adjusting for age, prevalence in hypertension and calf skinfold thickness, change in BF values remained lower (p < 0.05) in obese subjects compared to the normal weight subjects. Lastly, the absolute and percentage change in BF were significantly related to BMI (r = -0.44, p < 0.001, and r = -0.37, p < 0.001, respectively) and to waist circumference (r = -0.36, p = 0.001, and r = -0.32, p = 0.002).


CONCLUSIONS
Obesity and abdominal adiposity impair vascular reactivity in older men and women, and these deleterious effects on vascular reactivity are independent of conventional risk factors.
Acree
Luke S
LS
Department of Health and Exercise Science, University of Oklahoma, Norman, OK, USA. lacree@ou.edu
Comp
Philip C
PC
Whitsett
Thomas L
TL
Montgomery
Polly S
PS
Nickel
Kevin J
KJ
Fjeldstad
Anette S
AS
Fjeldstad
Cecilie
C
Gardner
Andrew W
AW