|Microvascular Angina||Procedure: Phase III group-based cardiac rehabilitation||Phase 2|
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
|Official Title:||The Impact of Cardiac Rehabilitation on Angina Frequency, Psychological Morbidity and Quality of Life in Women With Syndrome X|
|Study Start Date:||January 2003|
|Study Completion Date:||May 2005|
|Primary Completion Date:||May 2005 (Final data collection date for primary outcome measure)|
Experimental: Phase III cardiac rehabilitation
Phase III group-based cardiac rehabilitation classes, weekly
Procedure: Phase III group-based cardiac rehabilitation
Phase III group-based cardiac rehabilitation
Other Name: Cardiac rehab
No Intervention: Monitoring
Normal daily living, no extra visits to study centre
Very few clinicians treating patients with Syndrome X could dispute that despite an excellent prognosis, the debilitating symptomology and ineffective treatment regimes typical in this condition give patients a miserable quality of life. First identified by Kemp (1), the triad of angina pectoris, a positive exercise test for myocardial ischemia and angiographically smooth coronary arteries continues to perplex clinician seeking a useful treatment regime.
The possible pathophysiology of chest pain associated with Syndrome X is poorly understood in these patients. Suggested mechanisms include abnormal myocardial flow reserve due to coronary microvascular dysfunction ('microvascular angina') (2) or a generalised disorder of vascular function (3),(4) early signs of abnormal left ventricular function (5), which in some patients may deteriorate over time,(6) and abnormal visceral pain perception (7). Some patients exhibit insulin resistance (8). However, there have been few adequate systematic explorations of the psychological and social aspects of Syndrome X.
Several studies have found increased levels of anxiety in patients with normal or near normal coronary arteries in the presence of accompanying chest pain (9). Ruggeri et al (10) found higher level of neuroticism and anxiety in small group of patients with Syndrome X in comparison with patients with confirmed coronary artery disease. Panic disorders, sometimes associated with chest pain, are also often presented with depression, hypochondriasis or other somatoform disorders (11). Studies investigating various non-therapeutic treatment regimes have repeatedly shown that relaxation and stress reduction lead to fewer incidence of chest pain in Syndrome X patients (12). However, the same is also true for patients with CAD (13) along with many other conditions and disorders with related chronic pain (14).
Frequency and severity of chest pain has been shown to have a direct effect on quality of life in Syndrome X patients (15). Sand (16) found that over a 7-year follow-up, a higher percentage of Syndrome X patients had given up work, reduced their daily activities and reported worsening chest pain in comparison to patients with confirmed coronary disease. Persistent functional incapacity with concomitant high levels of chest pain in patients with normal or near normal coronary arteries was also found after an 11-year follow-up (9). Use of anti-anginals was higher, as was their self reported burden on the health service.
The Collins team recently performed the largest psychosocial investigation of postmenopausal women with Syndrome X ever undertaken (17). The Hearts and Minds Study, which involved 100 Syndrome X patients, 100 patients with CHD and 100 healthy volunteers found that Syndrome X patients suffered significantly higher levels of anxiety than CHD patients or healthy controls. A greater number of Syndrome X patients suffered clinical levels of anxiety and depression than CHD patients and healthy volunteers, along with suffering significantly higher levels of psychological suffering as measured by the Health Anxiety Questionnaire than healthy controls. We also found that Syndrome X patients with a small social network had higher levels of anxiety than their counterparts with a larger social support structure.
In order to address these findings, it is important to identify an intervention which not only reduces anxiety, but also promotes wellbeing, improves quality of life and augments the social support resource network available to Syndrome X patients. Cardiac Rehabilitation (CR) has consistently been shown to improve the psychological wellbeing in cardiac patients, as recent reviews have highlighted the beneficial effects of CR on symptoms of angina and dyspnoea, stress level and psychological functioning (18). CR has been shown to have a positive affect on reducing anxiety levels in cardiovascular patients (19), while high levels of depression, a frequent co-morbidity in MI patients, have been reduced by CR (20). Women in particular seem to gain most benefit from CR, as improvements in functional capacity, coronary risk and psychosocial wellbeing were equal or greater in women than men following rehabilitation (21). It has been suggested that CR may reduce anxiety in CHD patients by reducing uncertainty, providing patients with an optimistic yet realistic outlook of recovery, as well as providing psychological support and promoting coping (18). Few could argue that a similar outcome in Syndrome X patients would not be beneficial.
As well as promoting psychological wellbeing, CR also provides patients with a social support resource network. The adequacy of social support has been investigated in relation the prognosis of patients with CHD (22) when it was noted that inadequate tangible support was a significant predictor of both morbidity and mortality. Population based studies have consistently identified a link between social support and CHD morbidity and mortality in men, while disease severity and proliferation have been shown to be related to a lack of support in women (23). Epidemiological studies have also consistently found a link between depression, social isolation and predicted morbidity and mortality in CAD patients (24). It has been argued that CR provides the social context through which coronary prevention interventions are delivered (25) and that this extra social support may have an important part to play in the patients recovery from, and adaptation to, chronic illness (26).
The effect of exercise intervention on the frequency and severity of angina has been the object of investigation for many years. Some studies have reported a reduction in mean weekly episodes of angina of up to 91% using an acute exercise intervention in CHD patients (13) and while other studies have been unable to replicate such results, almost all highlight the beneficial effect of exercise on angina frequency. Nevertheless, very few studies have investigated the impact of exercise on Syndrome X, either from a psychosocial or physiological view-point. Erikkson et al (27) addressed the physical deconditioning apparent in many Syndrome X patients through the use of 8 weeks moderate intensity exercise. Time to pain improved dramatically, with no increase in maximum pain experienced, while peak exercise capacity, heart rate and systolic blood pressure also showed improvements. Exercise capacity and quality of life were also shown to increase following 8 weeks of physical training in separate group of Syndrome X patients (28).
Aerobic exercise has been repeatedly shown to have positive effects on psychological wellbeing, anxiety and depression (29). Patients suffering clinical levels of anxiety and depression have shown a reduction in the severity of their symptoms(30)while athletes and the very active became depressed when they were prevented from exercising(31). Studies involving exercise, anxiety and wellbeing the older population are limited, however subjective health and psychological wellbeing have been shown to be higher among older people who partake in regular exercise (32). Anxiety reduction and increased wellbeing has also been shown in elderly men following an 8-week weekly exercise intervention (33).
Therefore, we would like to explore the beneficial effects of cardiac rehabilitation in Syndrome X patients. Exercise is not currently recognised as a treatment regime for Syndrome X, either as a stand- alone intervention or in conjunction with any other therapy. Patients are currently given little advice or guidance relating to physical activity due to the lack of research and information regarding the potential benefit of exercise available to practitioners. Our previous investigations of Syndrome X have demonstrated a need for an intervention which would not only reduce the patients reported levels of anxiety, but also increase their perceived social support, psychological wellbeing and quality of life. CR has been shown to improve quality of life, reduce anxiety and decrease frequency of angina episodes in CHD patients through the use of exercise intervention and tangible social support. Therefore, we would like to investigate the following research questions:
Does cardiac rehabilitation:
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00123617
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00123617
|National Heart and Lung Institute, Imperial College London|
|London, United Kingdom, SW3 6LY|
|Principal Investigator:||Peter Collins, MD FRCP||National Heart and Lung Institute, Imperial College London|