04 Sep Faster Resting Heart Rate Linked To Metabolic Syndrome
Medical Research: What are the main findings of the study?
Prof. Zhang: Higher heart rate has emerged as a cardiovascular risk factor and is associated with higher mortality rate. However the mechanistic link between heart rate and mortality outcome in population has been missing.
The main findings of the present study in a relatively large population are two-fold: Firstly, there is a strong and positive association between resting heart rate and metabolic syndrome, which is defined when an adult has 3 of the following: obesity (waist circumference ≥90 cm for men or ≥80 for women); hypertriglyceridemia (triglycerides ≥1.7 mmol/L); low plasma level of high-density lipoprotein <1.03 mmol/L for men or <1.30 mmol/L for women); hypertension (systolic blood pressure/ diastolic blood pressure≥130/85 mmHg or current use of antihypertensive medications); hyperglycemia (fast blood glucose ≥5.6 mmol/L or previously diagnosed type 2 diabetes or current use of hypoglycaemic agents or insulin).
Secondly and more importantly, those without metabolic syndrome but with higher resting heart rate will have greater risk in developing metabolic syndrome in the near future. As such, the findings from both cross-sectional and longitudinal studies provide evidence that resting heart rate is an independent risk factor for existing metabolic syndrome and a powerful predictor for its future incidence.
Medical Research: What should clinicians and patients take away from your report?
Prof. Zhang: Clinicians and patients should pay more attention to resting heart rate. Physicians should routinely check and record resting heart rate for each clinic visitors. Heart rate measurement constitutes a simple and inexpensive approach to monitor general cardiovascular and metabolic health in individuals and in population. Those healthy and asymptomatic individuals with higher resting heart rate should be under surveillance, because they have greater risk in developing cardiovascular and metabolic disorders compared with those with slower heart rate.
Prof. Zhang: Given the results from the present and from other publications in the field, investigators can make scientific expedition in several ways in future studies, for example: to integrate the importance of resting heart rate as an independent risk factor into clinical outcome evaluation in pharmacological and non-pharmacological (i.e. lifestyle) trials or even prognostic analysis; to explore the necessity of deliberately targeting resting heart rate in order to reduce the incidence of metabolic syndrome; to re-evaluate the definition of conventionally ‘normal/physiological’ range of resting heart rate, which has been challenged but no consensus is made or in making.