Effects of bariatric surgery on male obesity-associated secondary hypogonadism: comparison of laparoscopic gastric bypass with restrictive procedures

Clinical evaluation of patients living with obesity

Obesity is a significant public health concern which is implicated in cardiometabolic disease, mechanical complications and psychiatric sequelae. BMI is currently used for diagnosis; however, it has limited sensitivity for adiposity in certain circumstances. This has led to the development of risk stratification tools like the Edmonton Staging criteria and the Kings Obesity Staging Criteria: these facilitate and guide comprehensive obesity-related complication assessment. Healthcare professionals working within obesity clinics should adopt evidence-based communication strategies, including shared decision-making, motivational interviewing, and realistic goal setting. It is also vital to avoid weight-stigmatising terminology in all aspects of care, as this can negatively impact patients. Primary care plays an essential part in obesity care and should work to promptly identify cases, initiate treatment and forward on to specialist services where appropriate. Clinical evaluation of the patient living with obesity should take a holistic approach and involve input from bariatric physicians, dietitians, psychologists, and bariatric surgeons, wider members of the multi-disciplinary team should be involved where needed. Clinicians should take a detailed history, examination and order laboratory tests to investigate for complications. Overall, with appropriate evaluation, these assessments can guide patient management and facilitate long-term improvement in health.

The male patient with obesity undergoing metabolic and bariatric surgery: changes in testosterone levels correlate with weight loss after one-anastomosis gastric bypass and Roux-en-Y gastric bypass

BACKGROUND

Male obesity secondary hypogonadism (MOSH) is a common disease among men with obesity and can be associated with metabolic syndrome and a variety of metabolic problems ultimately leading to androgen deficiency. Metabolic and bariatric surgery is a well-established treatment option associated with significant weight loss and reduction in metabolic co-morbidities.

OBJECTIVES

To evaluate the impact of surgery on plasma levels of sexual hormones and their effect on weight loss comparing 2 surgical methods (one-anastomosis gastric bypass [OAGB] and Roux-en-Y gastric bypass [RYGB]) in male patients with obesity.

SETTING

University hospital, Austria.

METHODS

Patients undergoing OAGB and RYGB between 2012 and 2017 were analyzed retrospectively. Follow-up in this study was up to 24 months. Systemic levels of sexual hormones (luteinizing hormone [LH]), follicle stimulating hormone [FSH], total testosterone [TT], sexual hormone binding globin [SHBG], 17 beta-estradiol [17bE], androstenedione [AS]) were retrieved at each visit. A linear mixed model was used to assess the correlation between changes in testosterone levels and percent excess weight loss (%EWL).

RESULTS

In 30.8% of all patients, MOSH was present preoperatively. A significant increase of TT was observed postoperatively that led to a complete resolution of hypogonadism within the period observed. Bioavailable testosterone (bTT) and FSH levels significantly increased each month of follow-up after surgery (all P < .01). Levels of 17bE did not change significantly after surgery. The overall change of TT, comparing preoperative and 1-year postoperative TT levels (ΔTT), significantly correlated with %EWL. Changes in TT levels were not affected by the choice of surgical method.

CONCLUSIONS

Serum plasma testosterone levels rise significantly after metabolic and bariatric surgery in male patients. The change of testosterone levels seems to play a role in continued weight loss after surgery. This is true irrespective of the surgical method used.

Adipose Tissue Dysfunction and Obesity-Related Male Hypogonadism

Obesity is a chronic illness associated with several metabolic derangements and comorbidities (i.e., insulin resistance, leptin resistance, diabetes, etc.) and often leads to impaired testicular function and male subfertility. Several mechanisms may indeed negatively affect the hypothalamic–pituitary–gonadal health, such as higher testosterone conversion to estradiol by aromatase activity in the adipose tissue, increased ROS production, and the release of several endocrine molecules affecting the hypothalamus–pituitary–testis axis by both direct and indirect mechanisms. In addition, androgen deficiency could further accelerate adipose tissue expansion and therefore exacerbate obesity, which in turn enhances hypogonadism, thus inducing a vicious cycle. Based on these considerations, we propose an overview on the relationship of adipose tissue dysfunction and male hypogonadism, highlighting the main biological pathways involved and the current therapeutic options to counteract this condition.

ENDOCRINE OBESITY: Pituitary dysfunction in obesity

Obesity, the growing pandemic of the 21st century, is associated with multiple organ dysfunction, either by a direct increase in fatty organ content or by indirect modifications related to general metabolic changes driven by a specific increase in biologic products. The pituitary gland is not protected against such a situation. Different hypothalamic-pituitary axes experience functional modifications initially oriented to an adaptive situation that, with years of obesity, turn to maladaptive dynamics that contribute to perpetuating obesity and specific symptoms of their hormonal nature. This paper reviews the recent knowledge on obesity-related pituitary dysfunction and its pathogenic mechanisms and discusses potential therapeutic actions aimed at contributing to ameliorating the complex treatment of severe cases of obesity.

The Mechanisms and Management of Age-Related Oxidative Stress in Male Hypogonadism Associated with Non-communicable Chronic Disease

Androgens have diverse functions in muscle physiology, lean body mass, the regulation of adipose tissue, bone density, neurocognitive regulation, and spermatogenesis, the male reproductive and sexual function. Male hypogonadism, characterized by reduced testosterone, is commonly seen in ageing males, and has a complex relationship as a risk factor and a comorbidity in age-related noncommunicable chronic diseases (NCDs), such as obesity, metabolic syndrome, type 2 diabetes, and malignancy. Oxidative stress, as a significant contributor to the ageing process, is a common feature between ageing and NCDs, and the related comorbidities, including hypertension, dyslipidemia, hyperglycemia, hyperinsulinemia, and chronic inflammation. Oxidative stress may also be a mediator of hypogonadism in males. Consequently, the management of oxidative stress may represent a novel therapeutic approach in this context. Therefore, this narrative review aims to discuss the mechanisms of age-related oxidative stress in male hypogonadism associated with NCDs and discusses current and potential approaches for the clinical management of these patients, which may include conventional hormone replacement therapy, nutrition and lifestyle changes, adherence to the optimal body mass index, and dietary antioxidant supplementation and/or phytomedicines.

Impact of Bariatric Surgery on Male Sexual Health: a Prospective Study

BACKGROUND

Obesity is a worldwide prevalent problem which negatively affects most of the human body systems. Male sexual dysfunction is a frequent problem in obese individuals. Nowadays, bariatric surgery is the most successful way for the management of morbid obesity. Recent research has concluded that it has a significant improving effect on sexual function.

AIM OF THE STUDY

This study aimed to assess the long-term effect of bariatric surgery on male sexual function.

PATIENTS AND METHODS

Sixty-six male patients indicated for bariatric surgery were enrolled in this prospective study. Only forty-eight of them completed the study. Patients were invited to fill the International Index of Erectile Function (IIEF) questionnaire twice, preoperatively (T1) and 12 months postoperatively (T2). Simultaneously, patients' serum testosterone levels were assayed.

RESULTS

At T2, the patients showed highly significant increase in the IIEF scores and the serum testosterone levels (p<0.001). Only weight and BMI were significant predictors of the IIEF scores. The same factors as well as the patients' age were predictors of the serum testosterone levels.

CONCLUSION

Bariatric surgery improves male sexual health. It is associated with significant increase in IIEF score and serum testosterone levels.

Metabolism of testosterone during weight loss in men with obesity

OBJECTIVE

Men with obesity often have low total and, with increasing adiposity, also low free testosterone (T) levels, which can partially restore during weight loss. Although this is partly explained by lower sex hormone binding globulin (SHBG) production and hypothalamic-pituitary downregulation, it is still not unravelled whether changes in androgen metabolism contribute to this phenomenon. Therefore, early changes in urinary excretion of T and its metabolites, during weight loss, in men with obesity are investigated.

DESIGN

Longitudinal study.

METHODS

Fourteen men with obesity (age 52(45-60)years, BMI 42.6(41.8-44.8)kg/m²) underwent gastric bypass surgery (GBS). Before surgery and 3 weeks, 6 weeks, 6 months and 1 year thereafter, 24 h urine and fasting serum samples were collected. Serum T and estradiol (E₂) levels were analyzed using LC-MS/MS and urinary metabolites of T with GC-MS/MS.

RESULTS

Already three weeks after GBS, serum SHBG and total T levels increased and remained increased as compared to baseline (all,p < 0.0125). Gonadotropins and (free) E₂ levels were unchanged, serum E₂/T ratio decreased (p < 0.0125). Total amount of urinary T increased non-significantly with mean increases of 53 % one year after GBS (p = 0.026). Urinary E₂/T, estrone/T, 3α-androstanediol/T and androsterone/T ratios decreased after GBS (p < 0.0125).

CONCLUSIONS

Restoration of circulating T levels during weight loss in this population is not only brought about by normalization of circulating SHBG levels, but increased production of and alterations in T metabolism also contribute. More specifically, relative decreases in aromatization and lower 5α-reductase activity might also be involved in restoring T levels in men with obesity.

Circulating Zinc and Copper Levels are Associated with Sperm Quality in Obese Men after Metabolic Surgery: A Pilot Study

(1) Background: Inadequate levels of several trace elements and vitamins may impair spermatogenesis in men. Although weight loss after metabolic surgery normalizes male reproductive hormones, sperm quality seems to not improve. We hypothesized that circulating concentrations of zinc, copper and other trace elements and vitamins might be involved. (2) Methods: We studied 20 men submitted to metabolic surgery at baseline and after two years. Hormone profiles, serum trace elements and vitamins were studied together with sperm analysis. (3) Results: At follow-up, serum testosterone, follicle-stimulating hormone and inhibin B concentrations increased showing a beneficial hormonal response for spermatogenesis. Conversely, serum copper, zinc and ferritin showed a decline after surgery. In total, 33% of men showed zinc deficiency, 27% copper deficiency and 20% iron deficiency, among others. Sperm analysis showed that all revaluated patients had at least one abnormal parameter. Serum zinc concentrations showed a positive correlation with progressive motility (r = 0.577, p = 0.031), and serum ferritin a positive correlation with sperm volume (ρ = 0.535, p = 0.049). Serum copper showed a weak and near significant correlation with motility (r = 0.115, p = 0.051). (4) Conclusions: The lack of improvement in sperm quality in obese men after metabolic surgery may be related to nutrient malabsorption, especially zinc, copper and iron.

Changes in the sexual functions of male patients and their partners after obesity surgery

Sexual functionality significantly contributes to health-related quality of life and can decrease with obesity. In this study, we aimed to prospectively evaluate the changes that occur in the erection function, sexual function and testosterone level of male patients scheduled to undergo bariatric surgery, as well as the changes in the sexual function of their partner. A total of 40 patients and their partners were included. International Index of Erectile Function-5 (IIEF-5) questionnaire and the Arizona Sexual Experience Scale (ASEX) were filled before and 6 months after surgery by the male patients. The ASEX form was also completed by the partners before and 6 months after the procedure. The height and weight measurements and testosterone values were measured before and after surgery. A statistically significant difference was found between the preoperative and post-operative IIEF-5 scores of the patients (p = 0.000 < 0.01). There was also a statistically significant difference between the patients and their partners' preoperative and post-operative ASEX scores. We can conclude that the partners of men with preoperative erection complaints also experience sexual dysfunction, and with the post-operative decrease in or disappearance of erection complaints, the sexual function of both male patients and their partners improves.

Differential effects of 11 years of long-term injectable testosterone undecanoate therapy on anthropometric and metabolic parameters in hypogonadal men with normal weight, overweight and obesity in comparison with untreated controls: real-world data from a controlled registry study

Background and significance

Obesity is a chronic disease, warranting long-term medical intervention. We evaluated effects of testosterone (T) therapy (Th) in men with T deficiency with normal weight, overweight and obesity on anthropometric and metabolic parameters, compared with untreated men.

Methods

Hypogonadal men (n = 823) with total T ≤ 12.1 nmol/L (age: 60.6 ± 7.0 years) participated in an ongoing registry study. Among these men 474 (57.6%) were obese, 286 (34.8%) overweight and 63 (7.7%) had normal weight. T undecanoate injections were administered to 428 men and 395 remained untreated. Anthropometric and metabolic parameters were measured at least twice a year and changes adjusted for confounding factors to account for baseline differences between groups.

Results

Long-term TTh in hypogonadal men, irrespective of weight at baseline, produced improvements in body weight, waist circumference (WC) and body mass index (BMI). Furthermore, TTh decreased fasting blood glucose and HbA_1c and improved lipid profiles. Gradual decreases in blood pressure (systolic and diastolic) and pulse pressure occurred in men treated with T in each group. Marked reductions in mortality and major cardiovascular events were recorded in men receiving TTh.

Conclusions

Our findings demonstrate that TTh produces reductions in weight, WC, and BMI. There were 77 (19.5%) deaths in the untreated groups and 23 (5.4%) in the T-groups. Based on these findings we suggest that long-term TTh in overweight and obese hypogonadal men produces progressive and sustained clinically meaningful weight loss and that TTh may contribute to reductions in mortality and incident major adverse cardiovascular events.

Male Obesity Associated Gonadal Dysfunction and the Role of Bariatric Surgery

Obesity is an ever growing pandemic and a prevalent problem among men of reproductive age that can both cause and exacerbate male-factor infertility by means of endocrine abnormalities, associated comorbidities, and direct effects on the precision and throughput of spermatogenesis. Robust epidemiologic, clinical, genetic, epigenetic, and preclinical data support these findings. Clinical studies on the impact of medically induced weight loss on serum testosterone concentrations and spermatogenesis is promising but may show differential and unsustainable results. In contrast, literature has demonstrated that weight loss after bariatric surgery is correlated with an increase in serum testosterone concentrations that is superior than that obtained with only lifestyle modifications, supporting a further metabolic benefit from surgery that may be specific to the male reproductive system. The data on sperm and semen parameters is controversial to date. Emerging evidence in the burgeoning field of genetics and epigenetics has demonstrated that paternal obesity can affect offspring metabolic and reproductive phenotypes by means of epigenetic reprogramming of spermatogonial stem cells. Understanding the impact of this reprogramming is critical to a comprehensive view of the impact of obesity on subsequent generations. Furthermore, conveying the potential impact of these lifestyle changes on future progeny can serve as a powerful tool for obese men to modify their behavior. Healthcare professionals treating male infertility and obesity need to adapt their practice to assimilate these new findings to better counsel men about the importance of paternal preconception health and the impact of novel non-medical therapeutic interventions. Herein, we summarize the pathophysiology of obesity on the male reproductive system and emerging evidence regarding the potential role of bariatric surgery as treatment of male obesity-associated gonadal dysfunction.

Secondary male hypogonadism: A prevalent but overlooked comorbidity of obesity

Male hypogonadism associated with obesity is a very prevalent condition and is increasing in parallel with the epidemic prevalence of obesity. Low testosterone levels promote higher fat mass with reduced lean mass. Male hypogonadism is related to an increase in associated cardiometabolic complications, such as hypertension, type 2 diabetes mellitus, the metabolic syndrome, and cardiovascular disease. Its influence as a comorbidity of obesity is becoming more evident and should be evaluated and treated in at-risk patients. Mechanisms involved in this relationship include body composition changes, the presence of adipokines, insulin resistance, and other factors, some of which are still unknown. Weight loss and treatment to replace testosterone levels improve the metabolic profile and quality of life in patients with obesity and hypogonadism; these beneficial effects depend on treatment modality and duration of therapy. The use of testosterone replacement therapy may be indicated, as it has not been shown to increase cardiovascular risk, and retrospective studies suggest a reduction in events in men with metabolic syndrome and type 2 diabetes.

Obesity and male hypogonadism: Tales of a vicious cycle

Obesity prevalence, particularly in children and young adults, is perilously increasing worldwide foreseeing serious negative health impacts in the future to come. Obesity is linked to impaired male gonadal function and is currently a major cause of hypogonadism. Besides signs and symptoms directly derived from decreased circulating testosterone levels, males with obesity also present poor fertility outcomes, further evidencing the parallelism between obesity and male reproductive function. In addition, males with androgen deficiency also exhibit increased fat accumulation and reduced muscle and mineral bone mass. Thus, compelling evidence highlights a vicious cycle where male hypogonadism can lead to increased adiposity, while obesity can be a cause for male hypogonadism. On the opposite direction, sustained weight loss can attain amelioration of male gonadal function. In this scenario, a thorough evaluation of gonadal function in men with obesity is crucial to dissect the causes from the consequences in order to target clinical interventions towards maximized improvement of reproductive health. This review will address the causes and consequences of the bidirectional relationship between obesity and hypogonadism, highlighting the implicit male reproductive repercussions.

Male Obesity-related Secondary Hypogonadism - Pathophysiology, Clinical Implications and Management

The single most significant risk factor for testosterone deficiency in men is obesity. The pathophysiological mechanisms involved in male obesity-related secondary hypogonadism are highly complex. Obesity-induced increase in levels of leptin, insulin, proinflammatory cytokines and oestrogen can cause a functional hypogonadotrophic hypogonadism with the defect present at the level of the hypothalamic gonadotrophin-releasing hormone (GnRH) neurons. The resulting hypogonadism by itself can worsen obesity, creating a self-perpetuating cycle. Obesity-induced hypogonadism is reversible with substantial weight loss. Lifestyle-measures form the cornerstone of management as they can potentially improve androgen deficiency symptoms irrespective of their effect on testosterone levels. In selected patients, bariatric surgery can reverse the obesity-induced hypogonadism. If these measures fail to relieve symptoms and to normalise testosterone levels, in appropriately selected men, testosterone replacement therapy could be started. Aromatase inhibitors and selective oestrogen receptor modulators are not recommended due to lack of consistent clinical trial-based evidence.

Changes in total sperm count after gastric bypass and sleeve gastrectomy: the BARIASPERM prospective study

BACKGROUND

The massive weight loss induced by bariatric surgery is associated with major benefits, but the effect on semen variables is still uncertain.

OBJECTIVES

To explore semen modifications with gastric bypass and sleeve gastrectomy.

SETTING

Five French University Hospitals.

METHODS

Male candidates for bariatric surgery with no history of infertility were recruited in this controlled prospective study. Sperm characteristics were collected before surgery and then 6 months and up to 12 months after surgery.

RESULTS

Forty-six adult men who underwent gastric bypass (n = 20) or sleeve gastrectomy (n = 26) were included. Total sperm count tended to be lower at 6 months and showed a significant decrease at 12 months in both surgery groups, at -69.5 million (-96.8 to -42.2 million; P = 0.0021). Total sperm count at 12 months relative to baseline was -41.4 million (P = .0391) after gastric bypass and -91.1 million (P = .0080) after sleeve gastrectomy. This was counterbalanced by an associated resolution of hypogonadism and decrease of DNA fragmentation in most patients with time after surgery.

CONCLUSION

Improvement in some semen variables after bariatric surgery observed in 3 previous studies is in contrast to the lower mean total sperm count found in this study at 1 year. The possible reversibility of this effect in the long term and the impact of surgery on fertility both remain unknown.

How much does obesity affect the male reproductive function?

Obesity is considered a worldwide epidemic disease. Many pathological conditions have been associated to obesity but the evidence relating to impaired fertility in males with obesity are contrasting. The aim of this review was to evaluate the interplay between obesity and male fertility, analyzing evidence from in vitro and in vivo studies to clinical trials. Obesity seems to be responsible of secondary hypogonadism. Here, we propose a new classification including central, peripheral and testicular factors that may affect the hypothalamic-pituitary-gonadal axis. Moreover, some studies demonstrated a direct action of obesity on sperm count and sperm characteristics, mediated by impaired Sertoli cells function, increased scrotal temperature, oxidative stress and accumulation of toxic substances and liposoluble endocrine disruptors in fat tissue. Recent studies have explored obesity-related epigenetic effects in sperm cells which may cause diseases in offspring. Moreover, not only in females but also males, obesity has been linked to reduced outcomes of in vitro fertilization, with a reduction of pregnancy rate and an increase of pregnancy loss. Finally, we reviewed the effects of weight modifications through diet or bariatric surgery on obesity-related reproductive dysfunction. In this regard, several studies have demonstrated that weight loss has been associated with a restoration of gonadal hormones levels.

Obesity, Male Reproductive Function and Bariatric Surgery

Overweight and obesity are associated with several chronic complications, such as type 2 diabetes, arterial hypertension and atherosclerotic cardiovascular diseases, with relevant consequences for patients and public health systems. Reproductive function abnormalities, such as obesity-related secondary hypogonadism, erectile dysfunction and infertility, represent other abnormalities negatively affecting the quality of life of men suffering from obesity but, despite their high prevalence, these are often understated because of a general lack of awareness in clinical practice. Obesity and gonadal function are closely related, with obesity being associated with hypogonadism that is reversed by body weight reduction thus ameliorating reproductive and sexual health. Clinical studies specifically evaluating the impact of non-surgical weight loss on testosterone levels sometimes showed conflicting results, whereas extensive literature has demonstrated that weight loss after bariatric surgery is correlated with an increase in testosterone levels greater than that obtained with only lifestyle interventions, suggesting the role of surgery also for the treatment of hypogonadism in obese male. However, studies concerning the consequences of bariatric surgery on overall reproductive function in the male, including also sexual activity and fertility, are limited and data regarding long-term effects are lacking. Here we present a brief review summarizing the evidence regarding the interplay between obesity and reproductive abnormalities in the obese male, together with the role of bariatric surgery for the treatment of these complications, describing both the positive effects and the limitations of this procedure.

Beneficial changes on plasma apolipoproteins A and B, high density lipoproteins and oxidized low density lipoproteins in obese women after bariatric surgery: comparison between gastric bypass and sleeve gastrectomy

Background

The beneficial effects in lipid profiles after obesity surgery might be associated with the decrease in cardiovascular risk. However, direct comparison between different surgical techniques has not been extensively performed.

Methods

In the present study we compare 20 obese women submitted to laparoscopic Roux en Y gastric bypass (RYGB) with 20 women submitted to sleeve gastrectomy (SG). Twenty control women matched for age and baseline cardiovascular risk were also included. Both patients and controls were followed up for 1 year after surgery or conventional treatment with diet and exercise, respectively. Lipid profiles were measured at baseline, 6 and 12 months later. Carotid intima-media thickness was measured by ultrasonography at baseline and at the end of the study.

Results

Women submitted to bariatric surgery showed a decrease in total cholesterol, triglycerides, oxidized-LDL and ApoB, and an increase in HDL and ApoA concentrations that occurred regardless of the surgical procedure. LDL concentrations, however, decreased only after RYGB whereas Lp(a) showed no changes. We did not observe any correlation between the changes in serum lipid concentrations and those in carotid intima-media thickness.

Conclusions

Sleeve gastrectomy and gastric bypass induce a similar beneficial effect on serum lipids in women with high cardiovascular risk 1 year after surgery.

Gastro-intestinal surgery and fertility

In France, 10 to 15% of couples in the overall population have a fertility problem. Preservation of sexual and reproductive function should be a major concern for all patients capable of procreation who undergo treatment for gastro-intestinal disease. The gastro-intestinal diseases most often responsible for fertility disorders include chronic inflammatory diseases, intestinal cancer and hereditary diseases, such as the Lynch syndrome and familial adenomatous polyposis. Obesity is responsible for a 20% loss of fertility but the effects of bariatric surgery on fertility are controversial. Nonetheless, in the light of progress in surgical techniques and better knowledge of gastro-intestinal disease the negative impact of surgery on fertility warrants attention. Effectively, fertility can be preserved after certain major gastro-intestinal operations such as cytoreductive surgery with intraperitoneal chemotherapy, total coloprotectomy with ileo-anal anastomosis and rectosigmoid resection, as long as the patient's age permits and resection of the reproductive organs is not necessary.

Prevalence of 'obesity-associated gonadal dysfunction' in severely obese men and women and its resolution after bariatric surgery: a systematic review and meta-analysis

BACKGROUND

Sexual dimorphism manifests noticeably in obesity-associated gonadal dysfunction. In women, obesity is associated with androgen excess disorders, mostly the polycystic ovary syndrome (PCOS), whereas androgen deficiency is frequently present in obese men in what has been termed as male obesity-associated secondary hypogonadism (MOSH). Obesity-associated gonadal dysfunction, consisting of PCOS in women and MOSH in men, is a frequent finding in patients with severe obesity and it may be ameliorated or even resolve with marked weight loss, especially after bariatric surgery.

OBJECTIVE AND RATIONALE

We aimed to obtain an estimation of the prevalence of obesity-associated gonadal dysfunction among women and men presenting with severe obesity and to evaluate the response to bariatric surgery in terms of resolution and/or improvement of this condition and changes in circulating sex hormone concentrations.

SEARCH METHODS

We searched PubMed and EMBASE for articles published up to June 2016. After deleting duplicates, the abstract of 757 articles were analyzed. We subsequently excluded 712 articles leaving 45 studies for full-text assessment of eligibility. Of these, 16 articles were excluded. Hence, 29 studies were included in the quantitative synthesis and in the different meta-analyses. Quality of the studies was assessed using the Quality index for prevalence studies and the Quality Assessment Tool for Before-After (Pre-Post) Studies With No Control Group available from the National Heart, Lung and Blood Institute. For meta-analyses including more than 10 studies, we used funnel and Doi plots to estimate publication bias.

OUTCOMES

In severely obese patients submitted to bariatric surgery, obesity-associated gonadal dysfunction was very prevalent: PCOS was present in 36% (95CI 22-50) of women and MOSH was present in 64% (95CI 50-77) of men. After bariatric surgery, resolution of PCOS was found in 96% (95CI 89-100) of affected women and resolution of MOSH occurred in 87% (95CI 76-95) of affected men. Sex hormone-binding globulin concentrations increased after bariatric surgery in women (22 pmol/l, 95CI 2-47) and in men (22 pmol/l, 95CI 19-26) and serum estradiol concentrations decreased in women (-104 pmol/l, 95CI -171 to -39) and to a lesser extent in men (-22 pmol/l, 95CI -38 to -7). On the contrary, sex-specific changes were observed in serum androgen concentrations: for example, total testosterone concentration increased in men (8.1 nmol/l, 95CI 6-11) but decreased in women (-0.7 nmol/l, 95CI -0.9 to -0.5). The latter was accompanied by resolution of hirsutism in 53% (95CI 29-76), and of menstrual dysfunction in 96% (95CI 88-100), of women showing these symptoms before surgery.

WIDER IMPLICATIONS

Obesity-associated gonadal dysfunction is among the most prevalent comorbidities in patients with severe obesity and should be ruled out routinely during their initial diagnostic workup. Considering the excellent response regarding both PCOS and MOSH, bariatric surgery should be offered to severely obese patients presenting with obesity-associated gonadal dysfunction.

Improvement in cardiovascular risk in women after bariatric surgery as measured by carotid intima-media thickness: comparison of sleeve gastrectomy versus gastric bypass

BACKGROUND

Bariatric surgery may diminish cardiovascular risk (CVR) and its associated mortality. However, studies that compare these effects with different techniques are scarce.

OBJECTIVE

To evaluate the changes in CVR as estimated by carotid intima-media thickness (IMT) after obesity surgery in women with high CVR as defined by the presence of metabolic syndrome.

SETTING

Academic hospital.

METHODS

We studied 40 severely obese women, of whom 20 received laparoscopic Roux en Y gastric bypass (RYGB) and 20 received sleeve gastrectomy (SG). Twenty control women matched for age and cardiovascular risk were also included. Patients and controls were evaluated at baseline and 1 year after surgery or conventional treatment with diet and exercise, respectively. Only 18 of the 20 women in the control group were available for analysis after 1 year. None of the women who had bariatric surgery was lost to follow-up.

RESULTS

Mean carotid IMT decreased 1 year after surgery irrespective of the surgical technique used, whereas no changes were observed in the control women who had conventional therapy (Wilks´ λ = .802, P = .002 for the interaction, P = .011 for RYGB versus controls, P = .002 for SG versus controls, P = .349 for RYGB versus SG).

CONCLUSION

Both RYGB and SG decrease CVR as measured by carotid IMT in obese women.

A nontargeted study of muscle proteome in severely obese women with androgen excess compared with severely obese men and nonhyperandrogenic women

OBJECTIVE

Androgen excess in women is frequently associated with muscle insulin resistance, especially in obese women with polycystic ovary syndrome. However, whether this is a primary event or the result of indirect mechanisms is currently debated.

DESIGN

This is an observational study.

METHODS

We obtained skeletal muscle biopsies during bariatric surgery from severely obese men (n=6) and women with (n=5) or without (n=5) androgen excess. We used two-dimensional differential gel electrophoresis and matrix-assisted laser desorption/ionization-time-of-flight/time-of-flight mass spectrometry to identify muscle proteins showing differences in abundance between the groups of obese subjects.

RESULTS

Women with hyperandrogenism presented the lowest abundances of glycogen phosphorylase, pyruvate kinase, β-enolase, glycerol-3-phosphate dehydrogenase, creatine kinase M-type, and desmin, whereas the abundances of these molecules were similar in control women and men.

CONCLUSION

According to our nontargeted proteomic approach, women with hyperandrogenism show a specific alteration of the skeletal muscle proteome that could contribute to their insulin resistance. Because men do not show similar results, this alteration does not appear to be the direct effect on muscle of androgen excess, but rather the consequence of indirect mechanisms that merit further studies.

Obesity and late-onset hypogonadism

Obesity and male hypogonadism (HG) are often associated, as demonstrated in all cross-sectional studies. Prospective studies have indicated that i) having HG at baseline increases the risk of visceral obesity (and metabolic syndrome) and that ii) obesity induces incident HG. Hence, there is a bidirectional relationship between the two conditions. This is the main topic of this review, along with some pathogenic considerations. Meta-analysis of intervention studies indicates that treating obesity is a very efficient treatment for obesity-induced HG. The mechanism by which obesity induces HG has not yet been completely understood, but dietary-induced hypothalamic inflammation, along with a decreased GnRH release, is plausible. Among patients seeking medical care for obesity, the proportion of HG is relatively high. The prevalence of obesity among patients referring for sexual dysfunction is also elevated. Hence, in symptomatic, obese, hypogonadal subjects, testosterone supplementation (TS) can be considered. Whereas long-term uncontrolled register studies suggest that TS could decrease weight, analysis of controlled studies only support a parallel increase in lean mass and decrease in fat mass, with a resulting null effect on weight. Considering that T induces an increase in muscle mass, it is conceivable that the amount of activity obese people can undertake after TS will increase, allowing a closer adherence to physical exercise programs. Some studies, here meta-analyzed, support this concept.

The complex and multifactorial relationship between testosterone deficiency (TD), obesity and vascular disease

Testosterone deficiency (TD) is a well-established and recognized medical condition that contributes to several co-morbidities, including metabolic syndrome, visceral obesity and cardiovascular disease (CVD). More importantly, obesity is thought to contribute to TD. This complex bidirectional interplay between TD and obesity promotes a vicious cycle, which further contributes to the adverse effects of TD and obesity and may increase the risk of CVD. Testosterone (T) therapy for men with TD has been shown to be safe and effective in ameliorating the components of the metabolic syndrome (Met S) and in contributiong to increased lean body mass and reduced fat mass and therefore contributes to weight loss. We believe that appropriate T therapy in obese men with TD is a novel medical approach to manage obesity in men with TD. Indeed, other measures of lifestyle and behavioral changes can be used to augment but not fully replace this effective therapeutic approach. It should be noted that concerns regarding the safety of T therapy remain widely unsubstantiated and considerable evidence exists supporting the benefits of T therapy. Thus, it is paramount that clinicians managing obese men with TD be made aware of this novel approach to treatment of obesity. In this review, we discuss the relationship between TD and obesity and highlight the contemporary advancement in management of obesity with pharmacological and surgical approaches, as well as utilization of T therapy and how this intervention may evolve as a novel approach to treatment of obesity in men with TD .

Effects of long-term treatment with testosterone on weight and waist size in 411 hypogonadal men with obesity classes I-III: observational data from two registry studies

BACKGROUND/OBJECTIVES

Long-term testosterone replacement therapy (TRT) up to 5 years has been shown to produce progressive and sustainable weight loss (WL) in hypogonadal men. This study investigated effects of long-term TRT up to 8 years in hypogonadal men with different obesity classes.

SUBJECTS/METHODS

From two independent observational registries we identified a total of 411 obese, hypogonadal men receiving TRT in urological clinics. The effects of TRT on anthropometric as well as metabolic parameters were studied for a maximum duration of 8 years, mean follow-up: 6 years. All men received long-acting injections of testosterone undecanoate in 3-monthly intervals.

RESULTS

In all three classes of obesity, T therapy produced significant WL, decrease in waist circumference (WC) and body mass index (BMI). In patients with class I obesity, mean weight decreased from 102.6±6.4 to 84.1±4.9 kg, change from baseline: -17.4±0.5 kg and -16.8±0.4%. WC in this group of patients decreased from 106.8±7.4 to 95.1±5.3 cm, change from baseline: -10.6±0.3 cm. BMI decreased from 32.69±1.4 to 27.07±1.57, change from baseline: -5.52±0.15 kg m(-2). In patients with class II obesity, weight decreased from 116.8±6.9 to 91.3±6.3 kg, change from baseline: -25.3±0.5 kg and -21.5±0.4%. WC decreased from 113.5±7.5 to 100.0±5.4 cm, change from baseline: -13.9±0.4 cm. BMI decreased from 37.32±1.45 to 29.49±1.71, change from baseline: -8.15±0.17 kg m(-2). In patients with class III obesity, weight decreased from 129.0±5.6 to 98.9±4.8 kg, change from baseline: -30.5±0.7 kg and -23.6±0.5%. WC decreased from 118.5±5.6 to 103.8±4.9 cm, change from baseline: -14.3±0.4 cm. BMI decreased from 41.93±1.48 to 32.46±1.59, change from baseline -9.96±0.29 kg m(-2).

CONCLUSIONS

Testosterone therapy appears to be an effective approach to achieve sustained WL in obese hypogonadal men irrespective of severity of obesity. Based on these findings we suggest that T therapy offers safe and effective treatment strategy of obesity in hypogonadal men.