Adaptation to acute coronary syndrome-induced stress with lowering of testosterone - a possible survival factor.

Objective: The objective of this study was to explore whether circulating testosterone (T) concentration is associated with the occurrence and risk for acute coronary syndromes (ACS). Method: This case-control study included male patients with acute myocardial infarction (AMI) (n=174) or unstable angina pectoris (UAP) (n=90) and healthy controls (n=238). Patients gave serum samples during the acute (n=264) and recovery (n=132) phases after a median of 10.5 months after the incident event. Secondary events (ACS or cardiovascular death) were registered during the following 6 years. Results: During the acute phase, AMI and UAP patients had similar significantly reduced concentrations of serum testosterone in comparison to controls. Testosterone associated inversely with weight, the degree of inflammation (i.e. C-reactive protein concentration) and signs of a chronic infection. In a multiadjusted Cox regression, when compared to testosterone concentrations considered high-normal (14.91-34.0 nmol/l), low-normal testosterone (9.26-14.90 nmol/l) in the acute phase predicted better prognosis for cardiovascular death rate with a hazard ratio (HR) of 0.17 (0.04-0.68, P=0.012). The increased testosterone concentrations after the recovery period did not associate with future cardiovascular disease events. Conclusion: Low-normal testosterone levels in the acute phase of ACS predicted better survival. The observation may indicate better adaptation to stress in survivors and warrants further study.