Posttransplant improvement in heart rate variability correlates with improved quality of life.

A prospective evaluation of 37 kidney and 20 kidney-pancreas transplant recipients was conducted to assess the relationship between pre- to posttransplant changes in heart rate variability (HRV) and quality of life (QoL). Assessments of 24-hour interbeat variability (pNN50 and rMSSD, SDNN, SDANN) and power spectral analysis of total, low (sympathetic), and high (parasympathetic) frequency components of HRV were performed. The Sickness Impact Profile was used to assess three dimensions of QoL (physical, psychosocial, and total functioning) prior to and at 6 months following transplantation. Changes in vagally mediated time domain measures of HRV were related to changes in physical and total functioning. Stronger correlations occurred between biobehavioral measures in kidney-pancreas recipients, with the strongest relationships occurring between changes in HRV frequency domain measures and changes in physical functioning. Findings indicate that changes in HRV and QoL are related, suggesting that interventions that enhance transplant recipients' HRV may also enhance their QoL.