Is male gynaecomastia associated with an increased risk of death? A nationwide register-based cohort study.

OBJECTIVE: Recent evidence supports that gynaecomastia may predict long-term morbidity, but evidence on the association with death and causes of death in males with gynaecomastia is lacking. The objective of this work is to estimate the risk of death in men diagnosed with gynaecomastia and evaluate whether this was conditional on underlying aetiologies of gynaecomastia. DESIGN: A nationwide register-based cohort study. SETTING: Nationwide Danish national health registries. PARTICIPANTS: Males were diagnosed with incident gynaecomastia (n=23 429) from 1 January 1995 to 30 June 2021, and each was age and calendar matched to five randomly population-based males without gynaecomastia (n=117 145). INTERVENTIONS: Not applicable. PRIMARY AND SECONDARY OUTCOMES: Gynaecomastia was distinguished between males without (idiopathic) and males with a known pre-existing risk factor. Cox regression models and Kaplan-Meier analyses estimated associations between gynaecomastia and death (all cause/cause specific). RESULTS: We identified a total of 16 253 males with idiopathic gynaecomastia and 7176 with gynaecomastia and a known pre-existing risk factor. Of these, 1093 (6.7%) and 1501 (20.9%) died during follow-up, respectively. We detected a 37% increased risk of all-cause death in males with gynaecomastia in the entire cohort (HR 1.37; 95% CI 1.31 to 1.43). Death risk was highest in males diagnosed with gynaecomastia and a known pre-existing risk factor (HR 1.75; 95% CI 1.64 to 1.86) compared with males with idiopathic gynaecomastia (HR 1.05; 95% CI 0.98 to 1.13). Specific causes of increased death were malignant neoplasms and circulatory, pulmonary and gastrointestinal diseases. Of the latter, an over fivefold risk of death from liver disease was detected (HR 5.05; 95% CI 3.97 to 6.42). CONCLUSIONS: Males diagnosed with gynaecomastia are at higher risk of death, observed mainly in males with a known pre-existing risk factor of gynaecomastia. These findings will hopefully stimulate more awareness among healthcare providers to potentially apply interventions that aid in alleviating underlying risk factors in males with this condition.

Increased Morbidity in Males Diagnosed With Gynecomastia: A Nationwide Register-based Cohort Study.

CONTEXT: Evidence on the long-term and general health of males with gynecomastia is lacking. OBJECTIVES: To assess health before and following a diagnosis of gynecomastia. METHODS: A register-based cohort study of 140 574 males, of which 23 429 were diagnosed with incident gynecomastia and age- and calendar-matched (1:5) to 117 145 males without gynecomastia from the background population. Males with gynecomastia were stratified into males without (idiopathic) or with a known preexisting risk factor (disease/medication). Cox and logistic regression models investigated associations of disease risk according to International Classification of Diseases 10th revision sections following and before gynecomastia diagnosis. RESULTS: A total of 16 253 (69.4%) males in the cohort were identified with idiopathic gynecomastia. These males had a statistically significant higher risk of future disease across all included disease chapters (hazard ratio [HR], 1.19-1.89), with endocrine diseases representing the greatest disease risk (HR, 1.89; 95% CI, 1.76-2.03). The highest subchapter disease risk was observed for disorders of the endocrine glands (odds ratio [OR], 7.27; 95% CI, 6.19-8.54). Similarly, the ORs of comorbidities were higher across all included disease sections (OR, 1.05-1.51), except for psychiatric disease (OR, 0.72; 95% CI, 0.68-0.78), with the highest association with musculoskeletal/connective tissue (OR, 1.51; 95% CI, 1.46-1.57) and circulatory (OR, 1.36; 95% CI, 1.29-1.43) diseases. CONCLUSIONS: The presence of idiopathic gynecomastia is an important first clinical symptom of an underlying disease and a significant predictor of future disease risk. These findings should stimulate more awareness among health care providers to increase identification of gynecomastia and its causes in males.

Association of gynecomastia with antidiabetic medications in older adults: Data mining from different national pharmacovigilance databases.

OBJECTIVE: Gynecomastia is a benign proliferation of the glandular breast tissue in men and is generally caused by a decrease in androgen and an increase in estrogen. Diabetes has been reported to be a risk factor for lowering androgen levels. Moreover, lowered androgen levels are more common in older men. In the present study, we aimed to evaluate the signals for gynecomastia in older men on antidiabetic medications. MATERIALS AND METHODS: A disproportionality analysis was performed to detect the signals for antidiabetic drug-associated gynecomastia in the U.S. Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) and the Japanese Adverse Drug Event Report database (JADER), using the reporting odds ratio (ROR) and information component (IC). RESULTS: Among 8 classes of medications for diabetes, a signal was detected only for dipeptidyl peptidase-4 (DPP-4) inhibitors (ROR: 1.90, 95% confidence interval (CI): 1.27 - 2.83; IC: 0.84, 95% CI: 0.26 - 1.42) in the FAERS. Regarding individual drugs, ROR and IC signals were detected for sitagliptin (ROR: 2.37, 95% CI: 1.48 - 3.79; IC: 1.12, 95% CI: 0.44 - 1.79) and vildagliptin (ROR: 3.34, 95% CI: 1.39 - 8.08; IC: 1.26, 95% CI: 0.07 - 2.44) in the FAERS and only for sitagliptin (ROR: 4.84, 95% CI: 1.92 - 12.2; IC: 1.48, 95% CI: 0.24 - 2.73) in the JADER. CONCLUSION: This study showed an association between DPP-4 inhibitor use and gynecomastia in older men with diabetes. Further pharmacoepidemiological studies are warranted to verify this finding.

Assessing the impact of a gynaecomastia assessment and treatment infographic in primary care in Greater Manchester.

INTRODUCTION: Men with gynaecomastia are routinely referred to breast clinics, yet most do not require breast surgical intervention. The aim of this study was to assess the impact of a novel point-of-care gynaecomastia decision infographic in primary care on the assessment, management and referral practices to tertiary breast surgical services. METHODS: A study was carried out of male patient referrals from primary care in Greater Manchester to a tertiary breast centre between January and March in 2018-2020. Referral patterns were compared before and after the infographic went live in general practices in Greater Manchester in January 2020. Data were collected for gynaecomastia referrals, including aetiology, investigation and management. RESULTS: In total, 394 men were referred to a tertiary breast centre from 163 general practices, of which 271 (68.8%) had a diagnosis of gynaecomastia. Use of the decision infographic by primary healthcare providers was associated with a decrease in male breast referrals with gynaecomastia (79.6% to 62.0%). Fewer gynaecomastia patients were referred with a benign physiological or drug-related cause after implementation of the infographic (52.2% vs 41.8%). Only 10 (3.7%) patients with gynaecomastia underwent breast surgery during the study period. CONCLUSION: Implementation of a gynaecomastia infographic in primary care in Manchester was associated with a reduction in gynaecomastia referrals to secondary care. We hypothesise that implementation of the infographic into primary care nationally may potentially translate to hundreds of patients receiving more specialty-appropriate referrals, improving overall management of gynaecomastia. Further study is warranted to test this hypothesis.

The prevalence of incidental finding of gynecomastia on thoracic computed tomography in the pediatric age group.

OBJECTIVES: This study aimed to determine the prevalence rate of gynecomastia, determine mean glandular breast tissue sizes, and evaluate whether there is any difference in the prevalence rate of gynecomastia according to age using three different reference values of glandular breast tissue size (≥5, ≥10, ≥20 mm) in the pediatric age group. METHODS: Glandular breast tissue sizes were measured retrospectively from thoracic computed tomography (CT) images taken for other reasons in 961 boys aged 1-18 years. RESULTS: When each breast was evaluated separately (1,922 breasts), gynecomastia was observed in 1,001 (52.1%), 719 (37.4%), and 216 (11.2%) breasts with ≥5, ≥10, and ≥20 mm considered as reference values, respectively. A significant difference was found in terms of gynecomastia (p<0.001) and mean glandular breast tissue size (p<0.001) with respect to age. CONCLUSIONS: New studies are currently needed to determine the glandular breast tissue size and the prevalence rate of gynecomastia in boys, and thoracic CT images can be used for this purpose.

Drug-induced gynecomastia: A systematic review and meta-analysis of randomized clinical trials.

OBJECTIVE: To review the evidence concerning treatment-related gynecomastia in patients taking spironolactone, antiandrogens, 5 alpha-reductase inhibitors, lipid-lowering and psychotropic drugs. MATERIAL AND METHODS: A search of Medline and EMBASE was performed up to 30 June 2021. We included randomized controlled trials comparing the effects of a drug belonging to these classes versus placebo or versus a drug of the same class. RESULTS: A total of 32 randomized controlled trials were included in the final review. There was an increased odds of gynecomastia in men receiving antiandrogens (OR = 17.38, 95% CI: 11.26 to 26.82; 6 trials, 9599 participants) and 5 alpha-reductase inhibitors compared to controls (OR = 1.77, 95% CI: 1.53 to 2.06; 7 series out of 6 trials, 34860 participants). The use of spironolactone in mixed gender populations was characterized by significantly higher odds of having gynecomastia compared to controls (OR = 8.39, 95% CI: 5.03 to 13.99; 14 trials, 3745 participants). No placebo-controlled trials focusing on the risk of gynecomastia in patients taking antipsychotic drugs was available, although there was a significant difference in the odds of having gynecomastia in a comparison between risperidone and quetiapine (OR = 4.32, 95% CI: 1.31 to 14.27; 3 trials, 343 participants). Limited evidence about the effects of statins on mammary glands was found. CONCLUSIONS: Antiandrogens and to a lesser extent 5 alphareductase inhibitors and spironolactone are associated with an increased risk of developing gynecomastia. Such effect can be explained by a modification of the testosterone to estradiol ratio. Gynecomastia (and galactorrhea) associated to the use of conventional and certain atypical antipsychotics can be related to high prolactin levels.

Incidence of gynaecomastia in Klinefelter syndrome adolescents and outcome of testosterone treatment.

The aim was to define the true incidence of gynaecomastia in adolescent boys with Klinefelter syndrome (KS) and to observe testosterone treatment effects on its duration by examination of the prospectively collected data from a specialist referral clinic for boys with KS, with comparison being made with KS boys identified by a historical newborn chromosome screening programme, together with chromosomally normal controls. Fifty-nine boys over age 13 years were referred to a specialist KS clinic; 21 developed gynaecomastia. The comparator was 14 KS boys identified at birth and 94 chromosomally normal control boys. Testosterone was routinely started at the onset of puberty if gynaecomastia, a manifestation of clinical hypogonadism, was present. Oral or transdermal testosterone was administered in the morning, in a reverse physiological rhythm, and doses were increased according to standard pubertal regimens. The incidence of gynaecomastia was not increased in both the KS cohorts compared with controls. The incidence and age of onset of gynaecomastia was 35.6%, at 12.3 (1.8) years in the KS clinic group; 36.0%, at 13.7 (0.6) years in the newborn survey group; and 34.0%, at 13.6 (0.8) years in the controls. Full resolution of the gynaecomastia occurred in the 12/14 KS clinic boys on testosterone treatment who had completed puberty and as long as adherence was maintained.Conclusion: The incidence of gynaecomastia in KS boys (overall 35.6%) is not increased over typically developing boys. Commencing testosterone when gynaecomastia develops with physiological dose escalation and full adherence can result in the resolution of the gynaecomastia. What is Known: • Gynaecomastia is a common feature in Klinefelter syndrome men. • Hypogonadism occurs from mid-puberty onwards with the absence of the usual rise in testosterone levels. What is New: • The incidence of pubertal gynaecomastia in Klinefelter syndrome is not different from typically developing boys. • Early and prompt starting of testosterone gel treatment and increasing the dose physiologically may help to resolve the gynaecomastia without the need for surgery.

Sports Medicine-Related Breast and Chest Conditions-Update of Current Literature.

ABSTRACT: This article reviews the most up-to-date evidence-based recommendations pertaining to breast and upper chest conditions, specifically for the sports medicine physician. Because of the unique circumstances of the team physician, they can see a wide breadth of pathology. Athletes may not have a primary care physician and may prefer to present to their team physician for breast and upper chest conditions. It is often more comfortable and convenient for athletes to seek treatment in the team setting. Therefore, it is important that the medical professional be aware of not only common pathology but also of that which is rarer. Any delay in evaluation can result in unnecessary morbidity and lead to complications or extended time lost from sport. Consequently, it also is important to facilitate an atmosphere encouraging early presentation and workup.

Marked Increase in Incident Gynecomastia: A 20-Year National Registry Study, 1998 to 2017.

CONTEXT: Gynecomastia, the proliferation of mammary glandular tissue in the male, is a frequent but little-studied condition. Available prevalence data are based on selected patient populations or autopsy cases with their inherent bias. OBJECTIVE: The objective of this work is to evaluate the age-related incidence and secular trends in gynecomastia in the general population. DESIGN: An observational, 20-year national registry study was conducted. SETTING: This population-based study used nationwide registry data. PARTICIPANTS: Participants included all Danish males (age 0-80 years) with a first-time diagnosis of gynecomastia. MAIN OUTCOME MEASURES: All Danish males (age 0-80 years) were followed up for incident diagnosis of gynecomastia in the Danish National Patient Registry from 1998 to 2017 using the International Codes of Diseases, 10th revision, and the Danish Health Care Classification System. Age-specific incidence rates were estimated. The hypothesis tested in this study was formulated prior to data collection. RESULTS: Overall, a total 17 601 males (age 0-80 years) were registered with an incident diagnosis of gynecomastia within the 20-year study period, corresponding to 880 new cases per year and an average 20-year incidence of 3.4 per 10 000 men (age 0-80 years). The average annual incidence was 6.5/10 000 in postpubertal males age 16 to 20 years and 4.6/10 000 in males age 61 to 80 years, with a respective 5- and 11-fold overall increase in these 2 age groups over the 20-year period. CONCLUSIONS: The incidence of gynecomastia has dramatically increased over the last 20 years, implying that the endogenous or exogenous sex-steroid environment has changed, which is associated with other adverse health consequences in men such as an increased risk of prostate cancer, metabolic syndrome, type 2 diabetes, or cardiovascular disorders.

Incidental Gynecomastia on Thoracic Computed Tomography in Clinical Practice: Characteristics, Radiologic Features, and Correlation With Possible Causes in South Korean Men.

Gynecomastia is a common incidental finding on thoracic computed tomography (CT). This study aimed to retrospectively determine the prevalence, imaging characteristics, and possible causes of incidental gynecomastia on thoracic CT. Records of male patients who underwent thoracic CT in 2015 were reviewed. The size and morphologic types (nodular, dendritic, and diffuse) were recorded for patients with breast glandular tissue larger than 1 cm, and the cutoff value of gynecomastia was defined as 2 cm. Additionally, the possible causes of gynecomastia obtained by reviewing patients' charts were recorded. CT-depicted gynecomastia was identified in 12.7% (650 of 5,501) of patients. The median size of the breast glandular tissue was 2.5 cm (interquartile range 2.2-3.1), and 36.8% of patients (239 of 650) had unilateral gynecomastia. The age distribution provided a bimodal pattern with two peaks in the age groups from 20 to 29 years old and greater than 70 years old. Chronic liver disease (CLD; p < .001), all stages of chronic kidney disease (CKD; p < .001), and medications (p = .002) were significantly associated with gynecomastia. Gynecomastia did not correlate with body mass index (p = .962). The size of breast glandular tissue was identified to be correlated with the morphologic type of breast tissue and the severity of CLD or CKD. The prevalence of incidental gynecomastia seen on thoracic CT was 12.7%. CT-depicted gynecomastia is not associated with obesity but with CLD, CKD, and medications. When gynecomastia is detected on CT, further evaluations and management might be required for patients with a treatable cause.

Gynaecomastia in the Durban Breast Unit: A Comparison of HIV- and Non-HIV-Infected Individuals.

BACKGROUND: The clinical profile of gynaecomastia patients, both in human immunodeficiency virus (HIV)-positive and HIV-negative patients, in resource-limited settings remains largely undocumented. The aim of this study was to compare and contrast these groups with a view to developing an appropriate treatment algorithm for the South African population. METHODS: A retrospective chart review at the Durban Breast Unit for the period 2000-2015 was undertaken with ethics approval [BE012/16 (sub-study of BCA173/15)]. Statistical analysis was done with IBM SPSS version 25. A p value <0.05 indicated statistical significance. RESULTS: One hundred and four patients were documented. The mean age was 37 years. Gynaecomastia was most commonly attributed to puberty, HAART, other medications or an idiopathic aetiology. HIV status was known in 49 patients. There was a 97% prevalence of HAART use in the HIV-positive subgroup (n = 31). Efavirenz was the most common inciting drug. Incidence of gynaecomastia correlated with duration of HAART use. Age, late presentation, advanced Simon grade and bilateral disease appear to necessitate surgical intervention more frequently. CONCLUSION: Patients on HAART are advised to seek early advice upon noticing gynaecomastia. Drug cessation/change is likely to assist only upon early presentation resulting in static progression, and ultimate cure would still entail surgical excision. Extensive blood and imaging studies should be done only where clinically indicated and can be considered in cases of recurrence post-surgery. Management option must be discussed with patients, and surgeons are required to be familiar with the various surgical techniques necessary to treat gynaecomastia.

The drugs that mostly frequently induce gynecomastia: A national case - noncase study.

AIMS: Drug-induced gynecomastia accounts for up to 25% of cases of gynecomastia. The objective of the present study was to provide a comprehensive overview of drug-induced gynecomastia on the basis of spontaneously reported adverse drug reactions (ADRs) in the French national pharmacovigilance database (FPVD). METHODS: We performed a case - noncase study of drug-induced gynecomastia. Cases corresponded to reports of gynecomastia recorded in the FPVD between 1 January 2008 and 31 December 2015. The noncases corresponded to all other spontaneously reported ADRs recorded in the FPVD during the same period. Data were expressed as the reporting odds ratio (ROR) and its 95% confidence interval. RESULTS: Of the 255,354 ADRs recorded in the FPVD between 1 January 2008 and 31 December 2015, 327 (0.31%) of relevant cases of gynecomastia and 106,800 noncases were analyzed. The RORs were statistically significant for 54 active compounds mentioned 429 times in cases of gynecomastia. A single drug was involved in 59% of cases. The most frequently implicated drug classes were antiretrovirals (23.5%), diuretics (15.5%), proton pump inhibitors (11.9%), HMG-CoA reductase inhibitors (9.1%), neuroleptics and related drugs (6.5%), calcium channel blockers (6.3%), and 5-alpha reductase inhibitors (4%). CONCLUSIONS: A comprehensive analysis of a national pharmacovigilance database highlighted the main drug classes suspected of inducing gynecomastia. A physiopathological mechanism (a hormone imbalance with elevated estrogen levels) is known or suspected for most of the drugs involved in gynecomastia. However, we noticed a lack of harmonization in the summary of product characteristics for original vs. generic medicines.

Gynecomastia in HIV-positive adult men receiving efavirenz-based antiretroviral therapy at Newlands clinic, Harare, Zimbabwe.

BACKGROUND: Gynecomastia is known to occur in some men taking an efavirenz-based antiretroviral therapy (ART) regimen. However, the incidence and outcomes of gynecomastia are not known in Zimbabwe. We described the characteristics and outcomes of gynecomastia among male patients on an efavirenz-based ART regimen. METHODS: We conducted a retrospective cohort review of data of all male patients aged ≥18 years taking an efavirenz-based regimen at Newlands Clinic, Harare, Zimbabwe before 31 March 2017. The primary outcome was gynecomastia as defined by breast/nipple enlargement reported by patient and confirmed by clinical palpation. Routinely collected data on demographics, baseline CD4, body mass index, duration on efavirenz, clinical presentation and outcomes were extracted from the clinic database and analysed using STATA 12.1. We investigated for any associations with concomitant medicines using cox regression. RESULTS: We analysed data for 1432 men with a median age of 40 years (IQR: 33-48). Half of the patients were in WHO stage 1 at ART commencement. Median body mass index and CD4 count at efavirenz commencement was 21 (IQR: 19-23) and 260 cells/mm3 (IQR: 126-412) respectively. The incidence of gynecomastia was 22/1000 person-years (IQR: 17.3-27.8). Over half of the cases (58%) were bilateral and 75% of all cases developed within two years of starting efavirenz. There were no significant associations with concomitant use of isoniazid (HR: 0.95, p = 0.87) or amlodipine (HR: 0.43, p = 0.24). Gynecomastia resolved in 83.5% of cases following withdrawal of efavirenz with a median time to resolution of 3 months (IQR: 2-9). CONCLUSION: The incidence of gynecomastia among patients taking efavirenz-based ART was low with most cases developing early on during treatment. Most cases resolved completely after withdrawing efavirenz.

Long-term consequences of androgen insensitivity syndrome.

Androgen insensitivity syndrome (AIS) is one of the most common sexual developmental disorders. According to the grade of the remaining androgen receptor (AR) function, AIS is classified as complete (CAIS), partial (PAIS) or mild (MAIS). In CAIS, the prevalence of germ cell tumours is increased compared with the general population. Although patients with CAIS used to undergo gonadectomy before puberty, nowadays a gonadectomy is recommended after spontaneous puberty, and up to 15% of patients retain their gonads. Nevertheless, the risk of germ cell tumour increases gradually after puberty. Annual follow-up with ultrasound or magnetic resonance imaging (MRI) is recommended. Unfortunately, these imaging methods are not sensitive enough for the diagnosis of an in situ germ cell tumour. In PAIS, the risk of germ cell tumour is higher than in CAIS; therefore, an early gonadectomy or an orchidopexy is indicated. Optimal hormone replacement therapy (HRT) is necessary for long-term health. The risks of osteopenia and of regimen osteoporosis are higher, ESPECIALLY in patients with early gonadectomy. Infertility is the rule in CAIS and PAIS. A few mutations do not affect fertility detrimentally, and these are responsible for MAIS. In PAIS leading to a predominantly male phenotype or ambiguous genitalia, multiple surgical procedures for gynaecomastia and/or hypospadias are required. Some small studies have found a higher risk of obesity, hyperlipidaemia and impaired insulin sensitivity. Psychological support is essential, as the prevalence of psychiatric disorders is increased. In conclusion, the diagnosis of AIS has long-term consequences for which shared decision-making (physicians, patients, parents) is appropriate.

Gynecomastia as a late complication of childhood cancer and its treatment that can affect the quality of life of male survivors.

Childhood cancer is relatively rare, and nowadays it is curable in more than 80% of children. Childhood cancer therapy is directed not only at improving survival but recently, we also concentrate on reducing late effects. We want children who have a diagnosis of cancer to survive and have an excellent quality of life. Gynecomastia and fertility outcome of the survivors of childhood malignancies should be considered in the follow-up of teen agers and young adults and should be approached in an accurate manner and managed in comprehensive teams.

The prevalence of premature thelarche in girls and gynecomastia in boys and the associated factors in children in Southern China.

BACKGROUND: To investigate the prevalence and risk factors of premature thelarche (PT) in girls and gynecomastia (GM) in boys in Southern China. METHODS: We conducted a cross-sectional study of preschool children across 9 cities in Zhejiang province. A total of 6273 children in the age-group of 2-7 years were recruited from January 2014 to March 2015. Relevant information was collected from mothers through face-to-face interviews. Logistic regression models were used to examine the correlates of PT and GM. Odds ratios (ORs) with 95% confidence intervals (CIs) are reported. RESULTS: The prevalence of PT among girls was 4.8% and that of GM among boys was 0.8%. One hundred girls were diagnosed with PT before the age of 2 years; 69 (69.0%) of these girls experienced spontaneous resolution of PT. Twenty-four boys were diagnosed with GM before the age of 2 years; 10 (41.7%) of these experienced spontaneous resolution of GM. Children borne of mothers with early onset of menarche and those belonging to high-income families were at a higher risk of premature breast development. Greater consumption of eggs was associated with premature breast development in early childhood. CONCLUSIONS: Socioeconomic status of family, early onset of menarche in mother, and consumption of eggs were strongly associated with premature breast development in early childhood.

Anabolic-androgenic Steroid Use Among Gynecomastia Patients: Prevalence and Relevance to Surgical Management.

BACKGROUND: Anabolic-androgenic steroids (AAS) are widely implicated in gynecomastia development. Surgery is the definitive treatment for cases persisting after cessation of AAS use. Currently, the relevance of AAS use to the surgical approach of gynecomastia has not been well explored. This study aims to compare patient characteristics, surgical outcomes, and surgical management of gynecomastia correction in AAS users versus nonusers. METHODS: A retrospective cohort study was performed with patients who underwent bilateral gynecomastia reduction surgery between January 2005 and August 2015 by a single surgeon at an academic hospital. Demographic data, AAS usage details, operative documentation, and follow-up outcomes were reviewed. RESULTS: A total of 964 cases were reviewed. Eleven percent (n = 105) of the patients had a history of AAS use. Compared with non-AAS users, AAS users were older at time of gynecomastia onset (15 years vs 13 years, P < 0.001) and surgery (28 years vs 25 years, P < 0.001). The AAS users had higher body mass index (27.3 kg/m vs 25.7 kg/m, P < 0.001) and a greater proportion of patients self-identified as bodybuilders (40.0% vs 22.4%, P = 0.002). Although no difference was found in the excised bilateral mastectomy volume (92.1 cm vs 76.4 cm, P = 0.20), The AAS users had significantly less lipoaspirate fat volume (250 mL vs 300 mL, P = 0.005). No difference was found in total complication rates. However, AAS users had significantly more revision mastectomy surgeries (3.8% vs 1.1%; P = 0.02). CONCLUSIONS: The unique breast composition of AAS users necessitates a surgical approach with meticulous intraoperative hemostasis and careful glandular excision to minimize recurrence and achieve comparable low complication rates.