Nowlin N S, Brick J E, Weaver D J, Wilson D A, Judd H L, Lu J K, Carlson H E
Ann Intern Med. 1986 Jun;104(6):794-8. doi: 10.7326/0003-4819-104-6-794.
Hormonal, neurologic, and vascular factors affecting potency were evaluated in 10 men with scleroderma and in 10 age-matched men with rheumatoid arthritis. Impotence was reported by 6 of the patients with scleroderma and none with rheumatoid arthritis. Studies of serum testosterone, free testosterone index, follicle-stimulating hormone, luteinizing hormone, prolactin, estradiol, thyroxine, and thyrotropin did not show a hormonal basis for impotence in any patient. Neurologic causes were not found on physical examination. Penile blood pressures were markedly abnormal in 4 impotent patients, intermediate in 2 impotent and 3 potent patients, and normal in 11 potent patients. A history of claudication and diminished ankle blood pressures indicated large vessel disease in 2 impotent patients; the remaining 4 impotent men had normal ankle pressures, suggesting that their poor penile blood pressures and impotence were due to small vessel disease, perhaps the small artery lesions of scleroderma.