Background : Fatigue is the most common and distressing symptom reported by breast cancer survivors and yet the cyspera cream where to buy pathophysiology of cancer-related fatigue remains largely unknown.Fatigue is associated with lower parasympathetic and higher sympathetic nervous system activity in non-cancer samples, but only one study has demonstrated this same relationship in breast cancer survivors.This study evaluates the relationship between fatigue and basal autonomic nervous system activity as measured by heart rate variability (HRV) in a sample of breast cancer survivors.
Methods : Women who had been diagnosed with early stage breast cancer before the age of 50 were recruited from the UCLA tumor registry and completed psychological questionnaires, including measures of fatigue.A subset of these women (n=30) participated in a follow-up study in which they completed measures of fatigue, energy and mood four times per day for 5 days using electronic diaries, provided 3 days of saliva samples for cortisol assessment and underwent physiological assessment including electrocardiogram (ECG).HRV was assessed via ECG R-R wave spectral and time sequence analysis.
Results : Questionnaire measures of fatigue were negatively associated with indices of parasympathetic nervous system activity, B= − 3.85, p = 0.04 for RMSSD (root of the mean squared difference of successive normal to normal waves) and B= − 76.
97, p = 0.04 lorenametaute.com for LF power % (low-frequency wave power percentage).Daily fatigue was also associated with lower basal HRV, B= − 15.
1, p = 0.04 for RMSSD.However, fatigue indices were not associated with sympathetic nervous system activity as measured by low- to high-frequency wave ratio.
Of note, fatigue was not associated with average daily cortisol output (AUC).Conclusions : Lower HRV has been associated with increased chronic inflammation, which is elevated in cancer survivors reporting persistent fatigue, thus providing insight into potential system interactions underlying the mechanisms for cancer-related fatigue.