RESUMO
BACKGROUND: C-reactive protein (CRP) is a marker of systemic inflammatory activity and may be modulated by physical fitness. Treadmill exercise testing is used to evaluate cardiovascular health through different variables including exercise capacity, heart rate and blood pressure responses. It was hypothesized that CRP levels are associated with these variables in men and women without overt heart disease. METHODS: A total of 584 asymptomatic subjects (317 [54.3%] women and 267 [45.7%] men) were enrolled in the present study and underwent clinical evaluation. CRP levels in men and women were examined relative to clinical characteristics and to variables of treadmill exercise testing: peak heart rate, exercise systolic blood pressure, exercise time, chronotropic reserve and heart rate recovery at the first and second minutes after exercise. Multivariate analysis was performed using a log-linear regression model. RESULTS: In women, exercise time on the treadmill exercise test (P=0.009) and high-density lipoprotein cholesterol levels (P=0.002) were inversely associated with CRP levels. Body mass index (P<0.001) and total cholesterol levels (P=0.005) were positively associated with CRP levels. In men, exercise time on the treadmill exercise test was inversely associated with CRP levels (P=0.015). Body mass index (P=0.001) and leukocyte count (P=0.002) were positively associated with CRP levels. CRP levels were not associated with peak heart rate, chronotropic reserve, heart rate recovery at the first and second minutes, or exercise systolic blood pressure. CONCLUSIONS: These findings contribute to the evidence that CRP is lower in individuals with better exercise capacity and demonstrate that this relationship is also apparent in individuals without overt heart disease undergoing cardiovascular evaluation through the treadmill exercise test. Lowering inflammatory markers may be an additional reason to stimulate sedentary individuals with low exercise capacity in the treadmill exercise test to improve physical conditioning through regular exercise.
RESUMO
PURPOSE: Vascular reactivity is involved in the regulation of vascular function either in normal conditions or in the pathophysiology of cardiovascular diseases. We tested the hypothesis that vascular reactivity evaluated by forearm blood flow may vary according to demographic and metabolic variables in a cohort of individuals without any evidence of heart disease after clinical examination. SUBJECTS AND METHODS: We studied 186 individuals (mean age 41.4 years, standard deviation 13.1 years; 95 (51%) men and 91 (49%) women. We investigated forearm blood flow and vascular conductance with venous occlusion plethysmography at baseline, during handgrip isometric exercise and during the recovery phase. Demographic and laboratory data were collected. Statistical analysis was performed with mixed linear models appropriate for repeated measurements. RESULTS: Mean forearm blood flow values in the different study conditions ranged between 1.7+/-0.47 mL.min(-1).100 mL(-1) of tissue and 2.82+/-1.13 mL.min(-1).100 mL(-1) of tissue. Forearm blood flow was higher in men than in women (P<0.005) and increased as the heart rate increased during handgrip maneuver (P<0.0001). Serum triglyceride levels were inversely related to forearm blood flow at baseline, during isometric exercise and recovery phase (P=0.0209). Body mass index was inversely related to forearm vascular conductance at baseline, during isometric exercise and recovery phase (P=0.0223). CONCLUSION: Our findings suggest that forearm blood flow and vascular conductance as a surrogate of the vascular function may be influenced by gender, heart rate, serum triglyceride levels and body mass index in individuals without overt heart disease.
