Circadian heart rate fluctuations predict cardiovascular and all-cause mortality in type 2 and type 1 diabetes: a 21-year retrospective longitudinal study

Eur J Prev Cardiol. 2024 Sep 26:zwae305. doi: 10.1093/eurjpc/zwae305. Online ahead of print.

Abstract

Background: Circadian heart rate (HR) fluctuations are associated with cardiovascular health. We examined their relationship with microvascular disease and long-term survival in patients with diabetes.

Methods: In this secondary analysis from the CHAMP1ON cohort of 497 adults with metabolic disease, 349 participants who had type 1 or type 2 diabetes, baseline 24h ambulatory blood pressure and HR monitoring (ABPM), and survival data over a 21-year observational follow-up were included. Clinical features, microvascular complications, and mortality rates were examined in participants with low circadian HR fluctuations (24h-HR SD below the median of 30.4) and blunted nocturnal HR dip (<10%).

Results: Low 24h-HR SD and blunted nocturnal HR dip were associated with an adverse cardiometabolic risk profile and 12-23% higher prevalence of cardiac autonomic neuropathy and nephropathy. After 6,251 person-years follow-up (21.0 [14.0-21.0] years), a total of 136 (39%) deaths occurred, of which 100 (68%) of cardiovascular cause. The low 24h-HR SD group had a higher risk for both cardiovascular (adjusted hazard ratio [aHR] 2.00, 95%CI 1.30-3.08, p=0.002) and all-cause mortality (aHR 1.61, 95%CI 1.13-2.29, p=0.009), compared with high 24h-HR SD. Similarly, patients with blunted nocturnal HR dip had a higher risk for cardiovascular (aHR 1.63, 95%CI 1.08-2.46, p=0.019) and all-cause mortality (aHR 1.69, 95%CI 1.20-2.38, p=0.003), compared with those with preserved nocturnal HR dip.

Conclusions: Impaired circadian HR fluctuations are associated with microvascular disease and long-term cardiovascular and all-cause mortality in diabetes. ABPM-derived HR measures may provide a widely available and inexpensive risk stratification tool in this high-risk population.

Keywords: ambulatory blood pressure monitoring; diabetes; heart rate variability; mortality; nocturnal dip.

Plain language summary

Circadian heart rate (HR) fluctuations are associated with cardiovascular health. We examined their relationship with microvascular disease and long-term survival in patients with diabetes. Impaired HR fluctuations measured by 24h ambulatory blood pressure and HR monitoring (ABPM) were associated with an adverse cardiometabolic risk profile, higher prevalence of cardiac autonomic neuropathy and nephropathy, and higher risk for cardiovascular and all-cause mortality over a 21-year follow-up. ABPM-derived HR measures may provide a cost-effective risk stratification tool in this high-risk population.