Department of Medicine, Manchester University NHS Foundation Trust, Manchester, United Kingdom.
Cardiovascular Research Group, The University of Manchester, Manchester, United Kingdom.
PLoS One. 2019 Sep 11;14(9):e0221992. doi: 10.1371/journal.pone.0221992. eCollection 2019.
Multiple factors contribute to sexual dysfunction in men with obesity. Sex hormone levels are commonly abnormal in men with obesity and this abnormality is often the focus of management in clinical practice. The role of small fibre neuropathy in obesity-related sexual dysfunction is not well established.
We aimed to investigate the relationship between sexual function, sex hormone levels and small nerve fibre morphology in men with severe obesity.
A prospective study of 29 men with severe obesity was undertaken. Sexual function was assessed using the European Male Ageing Study Sexual Function Questionnaire. Small nerve fibre morphology was quantified using corneal confocal microscopy. Sex hormone levels were measured by mass spectrophotometry.
Erectile dysfunction was present in 72% of the cohort with a higher prevalence of diabetes among the symptomatic group (88% vs 38%, p = 0.006). Corneal nerve fibre length (CNFL) and corneal nerve fibre density (CNFD) were both significantly lower in participants with erectile dysfunction compared to those without (p = 0.039 and p = 0.048 respectively). The erectile function score correlated with CNFL (r = -0.418, p = 0.034) and CNFD (r = -0.411, p = 0.037). Total testosterone and calculated free testosterone levels did not differ significantly between men with or without erectile dysfunction (median 8.8 nmol/L vs 9.0 nmol/L, p = 0.914; and median 176 pmol/L vs 179 pmol/L, p = 0.351 respectively), infrequent sexual thoughts (median 8.1 nmol/L vs 9.2 nmol/L, p = 0.650; and median 184 pmol/L, vs 176 pmol/L, p = 0.619 respectively) and decreased morning erections (median 9.0 nmol/L vs 8.8 nmol/L, p = 0.655; and median 170 pmol/L vs 193 pmol/L, p = 0.278 respectively).
Sexual dysfunction is highly prevalent in men with severe obesity. We found an association between small fibre neuropathy with erectile dysfunction with presence of diabetes a likely a significant contributing factor. We found no associations between testosterone levels with sexual symptoms (including frequency of sexual thoughts). The influence of small nerve fibre neuropathy on response to therapeutic interventions and whether interventions that improve small fibre neuropathy can improve erectile function in this population merits further study.
多种因素导致肥胖男性性功能障碍。肥胖男性的性激素水平通常异常，这种异常往往是临床实践管理的重点。小纤维神经病在肥胖相关性功能障碍中的作用尚未得到充分证实。
我们旨在研究严重肥胖男性的性功能、性激素水平和小纤维形态之间的关系。
对 29 名严重肥胖男性进行前瞻性研究。性功能使用欧洲男性衰老研究性功能问卷进行评估。使用角膜共聚焦显微镜定量小纤维形态。通过质谱法测量性激素水平。
该队列中 72%存在勃起功能障碍，症状组糖尿病患病率更高（88%比 38%，p = 0.006）。与无勃起功能障碍者相比，有勃起功能障碍者的角膜神经纤维长度（CNFL）和角膜神经纤维密度（CNFD）均显著降低（p = 0.039 和 p = 0.048）。勃起功能评分与 CNFL（r = -0.418，p = 0.034）和 CNFD（r = -0.411，p = 0.037）呈负相关。有或无勃起功能障碍的男性之间的总睾酮和计算的游离睾酮水平无显著差异（中位数 8.8 nmol/L 与 9.0 nmol/L，p = 0.914；中位数 176 pmol/L 与 179 pmol/L，p = 0.351），性思维不频繁（中位数 8.1 nmol/L 与 9.2 nmol/L，p = 0.650；中位数 184 pmol/L 与 176 pmol/L，p = 0.619）和晨勃减少（中位数 9.0 nmol/L 与 8.8 nmol/L，p = 0.655；中位数 170 pmol/L 与 193 pmol/L，p = 0.278）。
严重肥胖男性性功能障碍患病率很高。我们发现小纤维神经病与勃起功能障碍之间存在关联，糖尿病可能是一个重要的致病因素。我们发现睾酮水平与性症状之间没有关联（包括性思维的频率）。小神经纤维神经病对治疗干预反应的影响，以及改善小神经纤维神经病是否能改善该人群的勃起功能，值得进一步研究。
