Effect of a mobile application and smart devices on heart rate variability in diabetic patients with high cardiovascular risk: A sub-study of the LIGHT randomized clinical trial.

ABSTRACT

BACKGROUND: This investigation aims to evaluate the effect of a mobile application and smart devices on frequency and time domains of heart rate variability (HRV) in diabetic patients in 1-year follow-up. METHODS: This is post-hoc analysis of a diabetic subgroup of "Lifestyle Intervention usinG mobile technology in patients with high cardiovascular risk a pragmatic randomized clinical Trial" (LIGHT). One hundred and nine and 118 patients were enrolled in two arms the intervention plus usual care and the usual care arm. The study outcome was the 1-year HRV parameters adjusted to the baseline HRV parameters. HRV measures were recorded for every patient at the randomization and final visits with 24-hour Holter monitoring. RESULTS: There was an improvement in the standard deviation of normal to normal (SDNN) R-R intervals 24-hour by 4.8 (adjusted treatment effect 4.8, 95% confidence interval [CI], 0.1-9.5; P = 0.044) in the intervention-plus-usual-care arm compared to usual care after a 1-year follow-up. The improvement was also experienced in other HRV time domains including standard deviation of the mean R-R intervals calculated over a 5-minute period, SDNN, square root of the mean squared difference of successive R-R intervals, and the percentage of the differences between adjacent normal R-R intervals exceeding 50 milliseconds. A significant enhancement was also detected in HRV frequency domains of total power low frequency and high frequency in the intervention plus usual care compared to usual care after a 1-year follow-up. CONCLUSIONS: The mobile application and smart device technology compared to usual care alone improved HRV parameters in diabetic patients at 1-year follow-up.