shows the history of the 761 males who entered the DCCT. Of these, 735 survived and were eligible to participate in the UroEDIC assessment at the EDIC year 10 visit, 713 attended the EDIC year 10 visit, 591 (84.5%) completed the UroEDIC questionnaire, and 571 answered the erectile function question. Of these, 23% fulfilled the criteria for ED (i.e. reported “Very Low” or “Low” confidence).
Characteristics of the 571 men in UroEDIC (Supplemental Table
) revealed that at DCCT baseline, diabetes duration was significantly shorter in the conventional vs. intensive treatment group (p=0.03); at EDIC year 10, the proportion of participants with nephropathy, retinopathy, peripheral neuropathy, and hypertension were all lower in the intensive treatment group, reflecting the previously described benefits of intensive therapy.13, 15
Sildenafil citrate use was reported by 30 subjects (12 with ED and 18 without), representing about 5% of those in each treatment group and 9% of those reporting ED.
DCCT Treatment and Erectile Dysfunction
More conventional treatment group participants expressed “Very low” (17.5%) or “Low” (8.9%) confidence in erection than in the intensive treatment group (11.1% and 8.6%, respectively). Overall, ED was present in 26.5% and 19.6% of the former conventional and intensive groups, respectively.
presents the effects of DCCT intensive versus conventional treatment, separately within the primary and secondary cohorts, on the prevalence of ED after adjustment for age, HbA1c at DCCT eligibility and duration of diabetes. Within the primary cohort, DCCT treatment group had no significant effect (OR=1.24, 95%CI=0.68, 2.28), with an adjusted prevalence of 20.3% versus 17% in the conventional versus intensive treatment group. Conversely, in the secondary cohort, DCCT treatment group had a substantial effect (OR=0.33, 95%CI=0.18, 0.60) with an adjusted prevalence of 30.8% versus 12.8% in the conventional versus intensive group.
Table 1 Multivariable logistic regression model* examining the difference between DCCT intensive versus conventional glycemic therapy in the prevalence of erectile dysfunction at EDIC year 10 follow-up after trial completion separately within the primary prevention (more ...)
The treatment group effect in the primary cohort differed significantly from that in the secondary cohort (p=0.003). Increasing age and increased DCCT baseline HbA1c also had strong effects on the prevalence of ED. Results were unchanged in analyses including all 30 sildenafil users as having ED, or excluding them entirely.
HbA1c Measures and Erectile Dysfunction
DCCT mean HbA1c levels were substantially higher among those with ED versus those without in the secondary cohort, but with an attenuated difference in the primary cohort. () For every 10% higher mean DCCT HbA1c level (e.g. 8.8% versus 8%), the adjusted odds of ED increased by 55% (p<0.0001) in the secondary cohort, and by 21.5% (p=0.04) in the primary cohort. The difference in the HbA1c effect between cohorts approached significance (p=0.07). For every 10% increase in DCCT/EDIC mean HbA1c, the odds of ED increased by 97% in the secondary cohort versus 74% in the primary cohort, p<0.0001 for each.
Mean HbA1c levels by erectile dysfunction status at EDIC year 10 by primary and secondary cohort and adjusted odds of erectile dysfunction per 10% higher HbA1c levels.
Erectile Dysfunction Risk Factors at EDIC Year 10
compares clinical characteristics of the 132 men with ED to the 439 without ED. In unadjusted analyses, a number of factors were nominally associated with ED including age, DCCT therapy group, measures of HbA1c, presence of microvascular complications, cardiovascular factors, LUTS, and cigarette smoking, among others.
Distribution of clinical characteristics by erectile dysfunction status at EDIC year 10 follow-up after trial completion.
In adjusted analyses, increasing age had the strongest effect on prevalence of ED (χ2=29, p<0.0001, 13% greater odds per year of age, 95% CI=8.5, 20%), followed by DCCT/EDIC mean HbA1c (χ2=14.7, p=0.0002, 60% greater odds per 10% higher mean HbA1c, 95% CI=25, 105%). While retinopathy and nephropathy were not significant after adjusting for mean HbA1c, there remained a higher adjusted proportion with ED among those with peripheral neuropathy and LUTS versus not (33 vs. 17%, p=0.02) and (31 vs. 19%, p=0.04), respectively.