Clinical validation of a quality of life questionnaire in angina pectoris patients

Angina pectoris impairs patients' quality of life. In order to assess its impact on quality of life, a questionnaire was developed using a literature review and interviews with patients and clinicians. It consisted of a general profile (SF-36) which measured functional status, well-being, perceived health, and a specific index, the Angina Pectoris Quality of Life Questionnaire, supplemented by new items. The acceptability, internal consistency reliability and clinical validity of this 70-item questionnaire were analysed in a cross-sectional study. Of 197 coronary patients approached, 93% (n = 184) agreed to participate and 86% (n = 170) returned the mailed questionnaire. Mean age of patients was 67 years (+/- 10); 79% were male and 70% were retired. Sixty patients were asymptomatic and 110 reported anginal crises (Canadian Cardiovascular Society Classification: class I: 48; II: 37; III: 13; IV: 0; V: 12). Globally, angina pectoris was found to affect each quality of life concept measured: physical functioning, well-being, and perceived health. Quality of life profiles worsened in accordance with increasing severity of the condition, as stratified by angina pectoris class. Asymptomatic patients reported better general and specific profiles. These results support the feasibility and usefulness of evaluating quality of life using the questionnaire. The validation of the data is very encouraging and enables the questionnaire to be used in clinical trials.