Cardiovascular responses of women with chronic fatigue syndrome to stressful cognitive testing before and after strenuous exercise

Objective: The purpose of this study was to compare the cardiovascular resp onses of patients with chronic fatigue syndrome (CFS) to healthy control su bjects when performing stressful cognitive tasks before and after strenuous exercise. Method: Beat-by-beat blood pressure and electrocardiogram were r ecorded on 19 women with CFS and 20 healthy nonexercising (ie, sedentary) w omen while they performed cognitive tests before, immediately after, and 24 hours after incremental exercise to exhaustion. Results: Diminished heart rate (p < .01) and systolic (p < .01) and diastolic (p < .01) blood pressur e responses to stressful cognitive testing were seen in patients with CFS w hen compared with healthy, sedentary controls. This diminished stress respo nse was seen consistently in patients with CFS across three separate cognit ive testing sessions. Also, significant negative correlations between self- ratings of CFS symptom severity and cardiovascular responses were seen (r = -0.62, p < .01). Conclusions: Women with CFS have a diminished cardiovascu lar response to cognitive stress; however, exercise did not magnify this ef fect. Also, the data showed that the patients with the lowest cardiovascula r reactivity had the highest ratings of CFS symptom severity, which suggest s that the individual response of the patient with CFS to stress plays a ro le in the common complaint of symptoms worsening after stress.