Association Between Aortic Calcification Burden and the Severity of Erectile Dysfunction in Men Undergoing Dialysis: A Cross-Sectional Study - Beyond the Abstract

Aortic calcification is one of the markers for atherosclerosis and can be simply and quantitatively measured by computed tomography (CT) images.1,2 Because accelerated atherosclerosis is a major complication in patients with end-stage renal disease,3 it plays an important role in the pathogenesis of erectile dysfunction (ED).4,5 However, the association between aortic calcification burden and the severity of ED remains unclear. Thus, the present study aimed to investigate this association in men undergoing peritoneal dialysis (PD) and/or hemodialysis (HD).

This cross-sectional study included 71 men undergoing PD and/or HD between July 2016 and May 2018 at Mutsu General Hospital. ED was assessed with the Sexual Health Inventory for Men (SHIM). Patients were divided into the mild/moderate (SHIM score ≥8) and severe ED groups (SHIM score ≤7). Aortic calcification index (ACI) was examined as a clinical indicator of abdominal aortic calcification. ACI was quantitatively measured using abdominal CT images by evaluating 10 slices of the aorta scanned at 10-mm intervals above the bifurcation of the common iliac arteries as previously described.6 Each slice was divided into 12 sectors, and the numbers of sectors with calcification were counted. The ACI (%) was calculated by averaging the percentage of calcification-positive sectors in slices 1–10. Multivariable logistic regression analysis was performed to identify the significant factors associated with severe ED.

The median age of the study participants was 64 years; all had ED, with 65% having severe ED. Spearman’s rank correlation test demonstrated a significant negative correlation between SHIM scores and ACI (ρ = −0.304, P = 0.010) and between SHIM scores and cardio-ankle vascular index (CAVI) (ρ = −0.241, P = 0.043). On the other hand, no significant correlation was observed between SHIM scores and ankle-brachial index (ABI) (ρ = 0.191, P = 0.113). The severe ED group had significantly higher ACI than the mild/moderate ED group (70% vs. 28%, respectively, P = 0.001). The optimal cutoff value of ACI for severe ED was 82%; patients with ACI ≥82% had significantly higher prevalence of severe ED than those with ACI <82% (46% vs. 8.0%, respectively, P < 0.001). In the multivariable analyses, a slight association was observed between ABI and severe ED (odds ratio [OR]: 0.058, P = 0.072), whereas ACI was significantly associated with severe ED (OR: 1.022, P = 0.022).

Although accelerated atherosclerosis is a major complication and plays an important role in the pathogenesis of ED in men undergoing dialysis,3-5,7 to the best of our knowledge, no study has investigated the association between aortic calcification burden and the severity of ED, and this is the first study to investigate this association. We found that ACI was significantly associated with severe ED. These results might be helpful for further research to identify the optimal treatment for men suffering from severe ED.

In the present study, we evaluated aortic calcification burden as a surrogate marker of atherosclerosis. Ideally, the condition of the internal pudendal artery should be evaluated because this artery is responsible for the arteriogenic ED.8 However, it is difficult to evaluate atherosclerosis of the internal pudendal artery in clinical practice because of its size.9 On the other hand, aortic calcification burden can be easily and quantitatively measured by general CT images.6 It takes only 1–2 min to analyze a single subject. Because atherosclerosis theoretically affects all arteries at the same time to the same extent,10 it is reasonable to measure aortic calcification burden as a surrogate marker of atherosclerosis of penile arteries. Regarding CAVI and ABI, these indices were not selected as independent factors associated with severe ED in the present study. Moreover, it was reported that accurate ABI values might not be obtained in cases with high arterial calcification burden.11 Therefore, aortic calcification burden might be a better surrogate marker of atherosclerosis of the penile arteries, considering its correlation with the severity of ED, ease of measurement, and non-invasiveness. However, no study has demonstrated the correlation between aortic calcification burden and penile artery calcification burden. Further studies are needed to address this issue.

Although the present study has several limitations, we demonstrated that aortic calcification burden was significantly associated with severe ED in men undergoing dialysis.

Written by: Naoki Fujita & Shingo Hatakeyama, Hirosaki University Graduate School of Medicine, Hirosaki, Japan

References:

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