Does Vitamin D Deficiency Effect Heart Rate Variability in Low Cardiovascular Risk Population?

This study aimed to evaluate the cardiac autonomic dysfunction and the cardiac arrhythmia risk using heart rate variability parameters in subjects with vitamin D deficiency and low cardiovascular risk. One hundred five consecutive individuals, 54 patients with low vitamin D status and 51 healthy controls were enrolled in this study. The overall cardiac autonomic tone was quantified by using various heart rate variability parameters included mean RR interval, mean Heart Rate, mean of standard deviations of intervals for 24 hours (SDNN), standard deviation of averages of intervals (SDANN), mean of standard deviation of intervals for 5 minutes (SDNNI), root mean square of difference of successive intervals (rMSSD) and the proportion of intervals differing more than 50 ms (pNN50) values. The 12-lead ECG was recorded from each participant, and QT intervals were measured. Baseline demographic profiles were similar between two groups. The heart rate variability parameters such as mean RR interval, mean HR, SDNN, SDANN, SDNNI, rMSSD and pNN50 (%) values were not significantly different in patients with low vitamin D status compared to control group. The electrocardiography analysis revealed only slight but significant prolongation of corrected QT (QTc) intervals in the control group. HRV variables were not significantly altered in patients with vitamin D deficiency in low cardiovascular risk profile group. Further studies evaluating these findings in other cohorts with high cardiovascular risk are required.