[Factor analysis of traditional Chinese medicine syndromes in 815 patients with unstable angina].

OBJECTIVE To explore the laws of traditional Chinese medicine (TCM) syndromes in unstable angina, and to establish the preliminary diagnostic criteria for TCM syndromes. METHODS Multi-center prospective research on TCM syndromes in 815 cases of unstable angina was done with the nonlinear dimension reduction by factor analysis. RESULTS There were five extracted factors in factor analysis: F1, F2, F3, F4 and F5. F1 was yin deficiency of heart and kidney, F2 was deficiency of both heart and spleen, F3 was intermingled phlegm and blood stasis, F4 was qi deficiency and blood stasis, and F5 was yang deficiency and coagulated cold. Qi deficiency and blood stasis (F4) syndrome accounted for the maximum proportion. The diagnostic criteria for TCM syndromes were preliminarily and respectively established. CONCLUSION Qi deficiency and blood stasis is the key factor of pathogenesis. The factor analysis can help us classify traditional Chinese medicine syndromes and establish the preliminary diagnostic criteria.