Adults with higher resting heart rates are at increased risk for metabolic syndrome even if they have few other risk factors, according to findings published in the Journal of Diabetes.
“Given the enormous health and economic burden imposed by diseases associated with [metabolic syndrome], particular attention needs to be paid to the identification and prevention of [metabolic syndrome] and its components,” Jieli Lu, MD, PhD, of the National Clinical Research Center for Metabolic Diseases at Ruijin Hospital of Shanghai JiaoTong University School of Medicine in Shanghai, and colleagues wrote. “In addition to traditional [metabolic syndrome] risk factors, such as overweight/obesity, physical inactivity and dyslipidemia, identification of other independent risk factors may provide more insights into the pathogenic mechanisms underlying [metabolic syndrome] and elucidating novel targets for its prevention and treatment.”
Defining metabolic syndrome
For their cross-sectional study, Lu and colleagues recruited 9,486 adults aged 40 years or older from the Jiading District in Shanghai between March and August 2010. Measurements of resting heart rate, blood pressure, BMI, waist circumference, physical activity, fasting plasma glucose, 2-h post-load plasma glucose, triglycerides, total cholesterol, HDL, LDL and insulin resistance were collected at baseline.
Using resting heart rate measures, the researchers divided participants into one of five quintiles, which included those with a rate of 71 beats per minute or fewer (mean age, 58.9 years; 53.2% women), between 72 and 77 beats per minute (mean age, 57.7 years; 62.3% women), between 78 and 83 beats per minute (mean age, 57.3 years; 64.5% women), between 84 and 90 beats per minute (mean age, 57.6 years; 65.3% women) and 91 or more beats per minute (mean age, 58 years; 64.4% women).
Of the entire population, 26.1% (n = 2,476) met the diagnostic criteria for metabolic syndrome, which required at least three of the following: waist circumference of more than 102 cm in men or more than 88 cm in women; triglycerides of at least 1.69 mM; HDL of less than 1.03 mM in men or less than 1.29 mM in women; BP of at least 130/85 mmHg; and FPG of at least 6.1 mM. Participants with the highest resting heart rates had the highest prevalence (32.62%) of metabolic syndrome compared with those in the other four ranges (P < .0001), which all had a prevalence of less than 30%.
After adjusting for BMI, smoking and drinking status, education, physical activity and insulin resistance, participants with the highest resting heart rates were 1.42 times more likely to develop metabolic syndrome (OR = 1.42; 95% CI, 1.2-1.69) than those with the lowest hear rates (P < .0001). In addition, the researchers observed elevated 10-year atherosclerotic cardiovascular disease risk among men (OR = 1.92; 95% CI, 1.27-2.9) and women (OR = 2.14; 95% CI, 1.56-2.91) with the highest resting heart rates compared with those with lower rates.
The researchers noted a 13% increase in metabolic syndrome risk (95% CI, 1.08-1.18) for each resting heart rate increase of 10 beats per minute. Participants were more likely to have high BP (OR = 1.3; 95% CI, 1.24-1.36), high triglycerides (OR – 1.21; 95% CI, 1.15-1.27) and high fasting glucose (OR = 1.15; 95% CI, 1.11-1.2) with each 10-beats-per-minute increase in resting heart rate.
Additionally, the researchers found that BMI of less than 24 kg/m2 was more strongly associated with metabolic risk for each 10-beats-per-minute increase (OR = 1.32; 95% CI, 1.21-1.44) compared with those with higher BMI measures (OR = 1.07; 95% CI, 1.01-1.12). Similarly, they found higher odds for metabolic syndrome per 10-beats-per-minute increase among those aged younger than 65 years (OR = 1.19; 95% CI, 1.13-1.25) vs. those aged 65 years or older (OR = 0.98; 95% CI, 0.9-1.08), men (OR = 1.18; 95% CI, 1.09-1.27) vs. women (OR = 1.11; 95% CI, 1.05-1.18), those without diabetes (OR = 1.08; 95% CI, 1.02-1.15) vs. those with diabetes (OR = 1.02; 95% CI, 0.94-1.11), those without hypertension (OR = 1.19; 95% CI, 1.06-1.32) vs. those with hypertension (OR = 1.06; 95% CI, 1.01-1.12), those with normal lipids (OR = OR = 1.27; 95% CI, 1.17-1.37) vs. those with abnormal measures (OR = 1.03; 95% CI, 0.97-1.1), and those without insulin resistance (OR = 1.12; 95% CI, 1.05-1.19) vs. those with insulin resistance (OR = 1.06; 95% CI, 0.99-1.14).
“These observations suggest that [resting heart rate], a simple clinical measure, may improve the early detection of cardiometabolic risk,” the researchers wrote. “The data highlight the importance of [resting heart rate] as a distinct marker of metabolic status, independent of other major risk factors. In the light of these findings, [resting heart rate] may have potential value in improving the early detection of cardiovascular and metabolic diseases in the Chinese population, especially among relatively healthy individuals.” – by Phil Neuffer
Disclosures: The authors report no relevant financial disclosures.