Background
Coronary flow reserve (CFR) in the presence of non-obstructive coronary artery disease displays the ability of microcirculation to augment flow to the myocardium. Endogenous total testosterone (TT) exhibits vasodilator effects and the Mediterranean diet (Med-diet) promotes cardiovascular health. Erectile dysfunction (ED) in a milieu of subclinical microvascular damage often coexists with the decline of endogenous testosterone of the aging male population.
Purpose
To investigate the effects of male hypogonadism in CFR and the relation between the Med-diet and the TT of the andropause middle aged men with ED.
Methods
190 non-diabetic male patients with ED (mean age: 56yo) enrolled the study. Significant epicardial coronary artery disease was excluded after a negative for ischemia dobutamine stress echo test. We measured the CFR of the left anterior descending artery by performing an adenosine protocol (maximum dose 140μg/kg/min over 6 minutes). Measurements by the pulse wave Doppler were achieved at the middle/distal LAD segment under the guidance of color Doppler flow mapping. CFR was estimated as ratio between peak diastolic flow velocity following drug infusion and rest. CFR ratio ≥2 is considered as non-ischemic response and higher values indicate microvascular coronary integrity. TT was measured in all patients on blood samples taken before 09:00 am and hypogonadism was considered when TT <3,5 ng/ml. ED severity and adherence to the Med-diet were assessed by the SHIM-5 (range: 0–25) and the Med-diet (range: 0–55) scores. Higher values point to better erectile function and a great Med-diet compliance respectively. Finally, carotid – femoral pulse wave velocity (PWV) was assessed as index of central vascular stiffness (sphygmocor device).
Results
In bivariate analysis CFR ratio (mean value: 2,35) was positively related to TT (p<0,001, r=0,9), the SHIM-5 and the Med-diet score (p<0,05 for both r=0,45 and r=0,5 respectively).On the contrary, it was negatively related to the PWV (p<0,05, r=−0,35). Med-diet was related to the SHIM-5 score (p=0,01, r=0,363) and to TT (p=0,02, r=0,46). In multiple linear regression analysis relation of CFR to TT remain significant (p<0,01) after adjustment for age, body mass index (BMI), LDL, PWV, smoking habits and systolic blood pressure. We further stratified our population in to hypogonadics (HYPO, n=38, 20%) and patients with normal TT levels. Poor adherence to the Med-diet was the only factor related to hypogonadism (independent sample t-test p=0,005) as compared with age, BMI and smoking.
Conclusion
In middle aged men with ED endogenous testosterone enhances coronary microcirculation. Moreover the Med-diet regime may blunt the fall of androgens during andropause independently of other life-style parameters. We emphasize on this culinary preference to assist coronary microvascular physiology and maintain hormonal balance.