Increased waist circumference linked to high exercise BP
MedWire News: Healthy men and women with a large waist circumference have an increased exercise blood pressure (BP), a study suggests.
Further interventional studies are needed to investigate whether decreasing abdominal obesity will lead to improvements in exercise BP, and consequently reduce cardiovascular disease risk, say Caroline Rhéaume (Institut Universitaire de Cardiologie et de Pneumologie de Québec, Canada) and co-authors.
Their study included 317 apparently healthy men and women with a mean age of 34.8 years and mean body mass index of 26.1 kg/m2.
Multivariate analysis revealed that waist circumference accounted for 32.8% and 45.1% of the variance in exercise systolic BP in men and women, respectively (both p<0.0001).
Participants were classified into gender-specific tertiles according to insulin response (area under the curve, low: <40,785; intermediate ≥40,785 and <70,230; high: ≥70,230 pmol/L for men and low: <46,931; intermediate: ≥46,931 and <69,701; high: ≥69,701 pmol/L for women), or fitness level, which was measured during an exercise test in kilopond meters (kpm; low: <9.63; intermediate: ≥9.63 and <12.07; high: ≥12.07 kpm/kg for men and low: <6.93, intermediate: ≥6.93 and <8.65; high: ≥8.65 kpm/kg for women). They were then further subdivided into two groups, according to waist circumference.
Individuals with an increased waist circumference (≥94 cm for men, ≥80 cm for women) had higher exercise systolic BP compared with those with smaller waist circumferences, regardless of which tertile they were in for insulin resistance, at 10.6 versus 6.8, 12.2 versus 7.7, and 13.2 versus 8.7 mmHg, for the lowest to highest tertiles, respectively (p<0.05).
This association was also seen regardless of which tertile each participant was in for fitness levels, at 13.1 versus 8.2, 12.0 versus 7.9, and 10.6 versus 7.1 mmHg, respectively (p<0.05).
"Individuals with a high waist circumference have elevated exercise systolic blood pressure, regardless of their insulin sensitivity or level of cardiorespiratory fitness," they write.
Rhéaume and team note that individuals with insulin resistance and/or low fitness levels were characterized by abdominal obesity, suggesting that an increased waist circumference "captures" a large amount of metabolically active visceral fat.
"This may represent a key 'mediating factor' linking low cardiorespiratory fitness and/or insulin resistance to higher exercise systolic blood pressure," they explain.
"Identifying cardiometabolic risk factors for hypertension and the extent to which these risk factors contribute to BP are key to the development of successful BP managing strategies," Rhéaume et al conclude.
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By Piriya Mahendra