Additional studies are required to confirm the findings
Bariatric surgery could be effective in improving male’s sexual (erectile) function in patients with obesity, according to Chinese researchers, however, due to the limited number of studies evaluating this topic, the authors noted that additional studies are required to confirm their findings. The paper, ‘The relationships between bariatric surgery and sexual function: current evidence based medicine’, was published in BMC Urology.
The authors write several studies have studied the effect of bariatric surgery on male’s sexual function, however the results are inconsistent with significant improvements found in some studies but not in the other studies. Therefore, they performed a systemic review and meta-analysis to investigate the efficacy of bariatric surgery in promoting male’s sexual (erectile) function.
Following a literature review, 11 studies (370 patients) met the inclusion criteria and were included in the study for the meta-analysis. The International Index of Erectile Function (IIEF) score and Brief Male Sexual Function Inventory (BSFI) score were set as the primary outcome, which is to the authors’ knowledge, the first meta-analysis to evaluate the effect of bariatric surgery on male’s sexual function with both IIEF and BSFI scores enrolled for comparison.
From the results of studies using IIEF as the index measuring erectile function, the postoperative erectile function was significantly improved (p<0.001), with improvements also found in intercourse satisfaction (p=0.0002), orgasmic function (p=0.03), overall satisfaction (p=0.0002) and sexual desire (p=0.0001). Furthermore, total erectile function showed a 7.21-point increasement in these studies (p<0.001).
For studies using the BSFI to measure erectile function, favourable results showed improvement in erection (p<0.001), ejaculation (p<0.001), desire (p<0.001), problem assessment (p<0.001) and sexual satisfaction (p<0.001).
They write that the underlying mechanism of obesity-related sexual dysfunction has not been clearly elucidated, but previous studies have suggested an array of causes including:
- Psychological and social appearance, such as body image, depression etc, have a negative impact on self-esteem and the tendency of avoidance and initiation to sexual behaviour
- Negative effect of the comorbidities in obese people (diabetes, hypertension, metabolic syndrome, etc.) are associated with sexual dysfunction
- A correlation of sex hormones to sexual function are believed to be associated with obesity induced sexual dysfunction
In addition, they note that a number of biological mechanisms might account for the connection between obesity and sexual dysfunction. Obesity is linked to endothelial dysfunction and increased serum concentrations of vascular inflammatory makers. The visceral adipose tissue impact biochemical modulators and proinflammatory factors (such as IL-6, TNF-α, angiotensinogen, angiotensin-converting enzyme), were are associated with systemic and peripheral vascular inflammation and can subsequently lead to a decrease in NO synthase and NO activity, causing endothelial dysfunction.
Reduced adiponectin level has also been confirmed to be connected with endothelial dysfunction which leads to erectile dysfunction by influencing the structural integrity of the vascular bed in the penis and the progress of penile engorgement by reducing the blood flow of penile. Furthermore, abnormalities in sex hormone regulation and production are related to sexual dysfunction in men, with androgens essential in maintaining the libido and regulating erectile capacity in men. BMI has also been reported to be negatively associated with serum testosterone and a reduction in free testosterone and a reduction in total testosterone have been associated with weight increases.
“We found that the bariatric surgery could be effective in improving male’s sexual function in obese individuals, with significantly improved IIEF scores and BSFI scores. These results are in accordance with the results of recent studies,” the authors concluded. “With the limited number of studies evaluating the specific factor, including psychological parameter, PDE5i use, age and so on, and its influence on sexual function in obese individuals undergoing bariatric surgery, we could not make a comprehensive view on those factors. More well-designed studies conducted on this topic is needed to confirm our findings.”
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