Abstract 1049
CHRONIC FATIGUE SYNDROME: ILLNESS SEVERITY, SEDENTARY LIFESTYLE, BLOOD VOLUME AND CARDIAC STRUCTURE AND FUNCTION Virginia T. Coryell, M.S., Barry E. Hurwitz, Ph.D., Meela Parker, CCT, RDCS, Pedro Martin, M.D., Psychology, Arthur LaPerriere, Ph.D., Psychiatry & Behavioral Sciences, University of Miami, Coral Gables, FL, Nancy G. Klimas, M.D., George N. Sfakianakis, M.D., Martin S. Bilsker, M.D., Medicine, University of Miami, Miami, FL
This study evaluated cardiac structure and function in Chronic Fatigue Syndrome (CFS) and non-CFS subjects, while controlling for CFS illness severity and sedentary lifestyle. In addition, we examined whether differences in total blood volume (TBV) could account for differences in cardiac outcomes. Study groups were: severe CFS (n=30), non-severe CFS (n=26), sedentary control (n=30) and non- sedentary control (n=30). Severe illness in CFS subjects was defined as >=7 of 10 CFS symptoms, self-rated as moderate or severe, that persisted for >=6 mos. Sedentary and non-sedentary physical activity status were defined, respectively, as a reported energy expenditure of <=1500 and >=2200 kcals/wk. Measures were obtained from self- report of medical history, fatigue and physical activity, as well as echocardiography and dual tag blood volume testing. Among potential covariates, group differences emerged for age and education, and hence were controlled in analyses. The analyses showed that the severe CFS group relative to the non-CFS groups evidenced diminished cardiac index (CI) due to diminished stroke index (SI; ps<.05) and not to heart rate differences. The diminished SI in the severe CFS group was due to lower end diastolic volume (EDV) and contractility (VCFc; ps<.05), with no group differences in end systolic volume. Follow-up analyses showed that the percent difference from ideal TBV was lower in the severe CFS group than the non-severe and sedentary-control groups (adjusted meanSE: -6.0%1.3 vs. -1.6%1.3 vs. 6.4%1.8; p<.001). When these TBV differences were controlled, the group differences in CI, SI, EDV and VCFc were no longer significant. Notably, the cardiac measures in CFS subjects did not correlate significantly with reported fatigue. Therefore, the findings suggest that although a cardiac function deficit is more probable in severely-affected CFS persons, it is not linked to sedentary lifestyle or perceived fatigue, but is largely accounted for by a deficit in blood volume.
227) Abstract 1305
IS THERE A LINK BETWEEN THERAPEUTIC OUTCOME IN CHRONIC FATIGUE SYNDROME AND COMORBID DEPRESSION? Boudewijn Van Houdenhove, MD, PhD, Liaison Psychiatry, Patrick Luyten, PhD, Stefan Kempke, MA, Psychology, University of Leuven, Leuven, Belgium
Purpose of study: Although it is assumed that chronic fatigue syndrome (CFS) and depression may show complex psychobiological links, there is a paucity of research investigating the role of comorbid depression in CFS treatment. Therefore, in this study the impact of comorbid depression on therapeutic outcome in a large sample of CFS patients was studied. Methods: Quasi-experimental, phase-lagged study of two multidisciplinary group treatment modalities with different intensity (weekly versus monthly), carried out in a tertiary care rehabilitation setting with two groups of CFS patients (n=101 and n=91 respectively). Both treatments were based on cognitive behavioural principles and also comprised relaxation exercises, pacing instructions and physical reconditioning exercises. Before treatment, comorbid depression was measured by the Hospital Anxiety and Depression Scale (HADS). Consistent with the recommended cut-off point for the HADS depression subscale in CFS patients (Morriss & Wearden, 1998), a score of 10 or more was used as a cut-off point to categorize patients as depressed versus non-depressed. Results: In both treatment modalities, therapeutic outcome was very similar. Moreover, in both conditions comorbid depression was negatively associated with outcome. For instance, taking the results of the two groups together, 49.1% (n=57) of the patients showing no improvement met criteria for depression, whereas only 26.3% (n=20) of the improved patients were depressed (chi square = 9.956, p <.05). Conclusions: These findings point to the importance of attending to comorbid depression in treating CFS patients and are in line with the advice to customize CFS treatment to individual patient characteristics (Van Houdenhove & Luyten, in press).