Objective: To investigate the impact of resting heart rate (RHR) on new-onset diabetes (NOD) in population without hypertension.
Methods: This prospective cohort study was performed in 2006 and 2007 and screened 101 510 participants. All subjects were employees of the Kailuan Group, a state-run coal mining company. The observation cohort included 48 926 subjects with normal fasting blood glucose (FBG) <7.0 mmol/L, no history of diabetes, complete FBG and RHR examination data, systolic blood pressure <140 mm Hg (1 mm Hg = 0.133 kPa) , diastolic blood pressure <90 mm Hg, no history of hypertension, and no use of hypoglycemic agents or antihypertensive drugs.We excluded participants without a health examination in 2008-2009 or 2010-2011 and those with incomplete examination data. A total of 29 910 participants were included in the final analysis. The observation population was divided into four groups according to RHR data collected during 2006-2007 health examinations: quartile 1 (RHR<63 beats/min) ; quartile 2 (63 beats/min ≤ RHR<70 beats/min) ; quartile 3 (70 beats/min ≤ RHR<75 beats/min) ; quartile 4 ( RHR ≥ 75 beats/min). Kaplan-Meier analysis was used to calculate the incidence of NOD. The relationship between RHR and NOD was estimated using Cox proportional hazard analysis.
Results: The incidences of NOD/1000 person-years for the above quartiles of RHR were 11.22, 13.58, 13.96, and 17.55, respectively in the total observational population; the corresponding incidences were 12.17, 15.20, 16.08, 20.44, and 8.29, 9.38, 8.86, and 9.60 in men and women, respectively. Compared with quartile 1, Cox proportional hazard regression analysis showed that the other three RHR groups had an increased risk of NOD after adjusting for age, gender, systolic blood pressure, diastolic blood pressure, and other risk factors. The hazard ratio values for these groups were 1.20 (95%CI:1.04-1.40, P < 0.05), 1.25 (95%CI:1.07-1.45, P < 0.01) and 1.58 (95%CI:1.36-1.82, P < 0.01), respectively. Furthermore, after adjusted the FBG, risk of NOD was significantly higher in quartile 2 (HR = 1.21, 95%CI:1.04-1.40, P < 0.01) and quartile 4 (HR = 1.22, 95%CI:1.06-1.41, P < 0.01 compared that in quartile 1. After adjusting for the factors listed above, the influence of RHR on NOD was not significant in women (P > 0.05) , but there was still an increased risk of NOD in men compared with quartile 1 with hazard ratio values of 1.21 (95%CI:1.02-1.43, P < 0.05) , and 1.27 (95%CI:1.09-1.49, P < 0.01) for quartile 2 and quartile 4, respectively.
Conclusion: Higher RHR is linked with higher risk of NOD in population without hypertension.