Bioenergetics in clinical medicine XIV. Studies on an apparent deficiency of coenzyme Q-10 in patients with cardiovascular and related diseases.

Blood samples from 406 cardiac patients were analyzed by a differential assay of the specific activities (s.a.) of the succinate dhydrogenase-coenzyme Q-10 reductase to detect and quantitate existing deficiencies of coenzyme Q-10. 87/406, or ca. 20%, showed a mean lower basal S.A. and a mean higher per cent deficiency than a control group; both differences were significant (p is less than 0.001). The remaining 319 patients (80%) showed a negligible deficiency, but a mean low basal S.A., significant by p is less than 0.001. Cardiac patients may show low S.A.'s (sub-normal) of this CoQ-10-enzyme with or without a deficiency of CoQ-10. The desirable state for the patient is a normal level of the enzyme for bioenergetics and no deficiency of CoQ-10. Previously, a deficiency of CoQ-10 was found for cardiac biopsies from surgery; now, blood samples reveal the same deficiency. Frequent correlation between deficiencies in the blood and cardiac tissue is expected. This CoQ-10-enzyme in blood can aid patient selection for the clinical administration of CoQ-10 to cardiac patients.