DIABETES CARE, VOLUME 21, NUMBER 11, NOVEMBER 1998 1973 E rectile dysfunction (ED) is a common complication of diabetes and an impor- tant cause of decreased quality of life in diabetic men (1–3). Its prevalence varies widely among studies, ranging from 20 to 70% (1,4–14). Several selective mecha- nisms could explain these differences. Study populations differ in age, type, and severity of diabetes and criteria for diagnosis of ED. Furthermore, most studies include only a limited number of subjects (a few hun- dred), often from selected centers. The prevalence of ED among diabetic men rises with age. It also seems to be related to the duration of diabetes, the degree of metabolic control, and the pres- ence of other complications (4,10,14). The quantitative role of these factors has never been well defined, and data are scant on what role is played in diabetic men by the potential determinants of ED in the general population, such as smoking and alcohol consumption. To offer further data on the prevalence and risk factors for ED in diabetic men, we conducted a large cross-sectional study of about 10,000 diabetic men in Italy, an area not investigated in previous epidemiologi- cal studies, which were generally con- ducted in North American and other European countries. RESEARCH DESIGN AND METHODS — Eligible for the study were men aged 20–69 years with a diagno- sis of IDDM or NIDDM lasting 1–30 years, who attended follow-up visits on randomly selected days in 178 diabetes centers in Italy during the period of May–September 1996. A total of 10,157 men entered the study. The average number of men at each center was 57 (range 15–115). All subjects were invited to a confiden- tial interview carried out by medical staff of the center during the visit at which they were identified. Age, weight, height, marital status, cigarette smoking, weekly alcohol consumption, diabetic pathology and treat- ment, diabetes-related complications, other medical history, and current use of medica- tions were recorded. Whenever useful, infor- mation given by the patient was checked with the medical records. In particular, the presence of chronic complications (vascular disease of the lower extremities, coronary heart disease, nephropathy, autonomic and motor-sensory neuropathy, diabetic foot, retinopathy), regardless of their severity, was reported in the questionnaire after checking the information collected in the clinical chart. Patients were also asked about their ability to achieve and maintain an erection sufficient for satisfactory sexual perfor- mance. If they answered that they were sat- isfied, the interview ended. If they answered that they were unsatisfied, they were defined as patients with ED. In that case, the men were further questioned about the severity of their sexual function problems. Incomplete ED was defined as only some sexual perfor- mances being considered unsatisfactory; complete ED was defined as all sexual per- From the Cattedra Malattie Metaboliche (D.F.), Università di Padova, Padova; the Prima Divisione Medica (C.C.), Ospedale di Parma, Parma; the Cattedra di Endocrinologia (F.S.), Università di Perugia, Perugia; the Istituto “Mario Negri” (A.B., L.C., F.P.); the Direzione Medica (M.L.), Pharmacia and Upjohn Italia, Milan, Italy; and Research and Development (E.C.), Medical Department, Pharmacia and Upjohn, Kalamazoo, Michigan. Address correspondence and reprint requests to Fabio Parazzini, Istituto “Mario Negri,” via Eritrea 62, 20157 Milan, Italy. Received for publication 8 April 1998 and accepted in revised form 24 July 1998. Abbreviations: ED, erectile dysfunction; OR, odds ratio. A table elsewhere in this issue shows conventional and Système International (SI) units and conversion factors for many substances. Erectile Dysfunction in Diabetic Subjects in Italy O R I G I N A L A R T I C L E OBJECTIVE — Our objective was to analyze the prevalence and risk factors for erectile dys- function (ED) in men with diabetes in Italy in a cross-sectional study. RESEARCH DESIGN AND METHODS — Eligible for the study were men aged 20–69 years with a diagnosis of IDDM or NIDDM who were observed on randomly selected days in 178 diabetes centers in Italy. ED was defined as a failure to achieve and maintain an erection sufficient for satisfactory sexual performance. RESULTS — Of the 9,868 diabetic men interviewed, 3,534 (35.8%) reported ED. The prevalence increased with age, from 4.6% in men aged 20–29 to 45.5% in those aged 60 years (test for trend, P = 0.0001). After taking into account the confounding role of age, men with NIDDM reported ED less frequently than did men with IDDM (odds ratio [OR], 0.7; 95% CI 0.6–0.8). In comparison with men reporting diabetes lasting 5 years, the ORs for ED were 1.3 and 2.0 for subjects with diabetes lasting 6–10 and 11–30 years, respectively. In compari- son with men with good metabolic control, the ORs for ED were 1.7 and 2.3 in men with fair and poor control, respectively. A history of diabetes-related arterial, retinal, or renal diseases and neuropathy was associated with an increased risk of ED. Finally, in comparison with never- smokers, the ORs for ED were 1.5 (95% CI 1.3–1.6) for current smokers and 1.4 (95% CI 1.3–1.6) for ex-smokers. The OR increased with number of cigarettes smoked per day: in com- parison with men smoking 12 cigarettes per day, the OR was 1.5 (95% CI 1.3–1.7) for those smoking 30 cigarettes day. CONCLUSIONS — The study offers a quantitative estimate of the prevalence of ED and of its main risk factors in Italian men with diabetes. Diabetes Care 21:1973–1977, 1998 DOMENICO FEDELE, MD CARLO COSCELLI, MD FAUSTO SANTEUSANIO, MD ANGELA BORTOLOTTI, SCD LILIANE CHATENOUD, SCD ENRICO COLLI, MD MARINA LANDONI, SCD FABIO PARAZZINI, MD ON BEHALF OF GRUPPO ITALIANO STUDIO DEFICIT ERETTILE NEI DIABETICI P a t h o p h y s i o l o g y / C o m p l i c a t i o n s