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Journal of the American Academy of... Jul 2017Androgenetic alopecia, or male pattern hair loss, is a hair loss disorder mediated by dihydrotestosterone, the potent form of testosterone. Currently, minoxidil and... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Androgenetic alopecia, or male pattern hair loss, is a hair loss disorder mediated by dihydrotestosterone, the potent form of testosterone. Currently, minoxidil and finasteride are Food and Drug Administration (FDA)-approved, and HairMax LaserComb, which is FDA-cleared, are the only treatments recognized by the FDA as treatments of androgenetic alopecia.
OBJECTIVE
This systematic review and meta-analysis assesses the efficacy of nonsurgical treatments of androgenetic alopecia in comparison to placebo for improving hair density, thickness, growth (defined by an increased anagen:telogen ratio), or subjective global assessments done by patients and investigators.
METHODS
A systematic review of randomized controlled trials was conducted. PubMed, Embase, and Cochrane were searched up to December 2016, with no lower limit on the year. We included only randomized controlled trials of good or fair quality based on the US Preventive Services Task Force quality assessment process.
RESULTS
A meta-analysis was conducted separately for 5 groups of studies that tested the following hair loss treatments: low-level laser light therapy in men, 5% minoxidil in men, 2% minoxidil in men, 1 mg finasteride in men, and 2% minoxidil in women. All treatments were superior to placebo (P < .00001) in the 5 meta-analyses. Other treatments were not included because the appropriate data were lacking.
LIMITATIONS
High heterogeneity in most studies.
CONCLUSIONS
This meta-analysis strongly suggests that minoxidil, finasteride, and low-level laser light therapy are effective for promoting hair growth in men with androgenetic alopecia and that minoxidil is effective in women with androgenetic alopecia.
Topics: Alopecia; Finasteride; Humans; Low-Level Light Therapy; Minoxidil; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 28396101
DOI: 10.1016/j.jaad.2017.02.054 -
The Journal of Steroid Biochemistry and... Jun 2021Higher endogenous testosterone levels are associated with reduced chronic disease risk and mortality. Since the mid-20th century, there have been significant changes in... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Higher endogenous testosterone levels are associated with reduced chronic disease risk and mortality. Since the mid-20th century, there have been significant changes in dietary patterns, and men's testosterone levels have declined in western countries. Cross-sectional studies show inconsistent associations between fat intake and testosterone in men.
METHODS
Studies eligible for inclusion were intervention studies, with minimal confounding variables, comparing the effect of low-fat vs high-fat diets on men's sex hormones. 9 databases were searched from their inception to October 2020, yielding 6 eligible studies, with a total of 206 participants. Random effects meta-analyses were performed using Cochrane's Review Manager software. Cochrane's risk of bias tool was used for quality assessment.
RESULTS
There were significant decreases in sex hormones on low-fat vs high-fat diets. Standardised mean differences with 95 % confidence intervals (CI) for outcomes were: total testosterone [-0.38 (95 % CI -0.75 to -0.01) P = 0.04]; free testosterone [-0.37 (95 % CI -0.63 to -0.11) P = 0.005]; urinary testosterone [-0.38 (CI 95 % -0.66 to -0.09) P = 0.009]; and dihydrotestosterone [-0.3 (CI 95 % -0.56 to -0.03) P = 0.03]. There were no significant differences for luteinising hormone or sex hormone binding globulin. Subgroup analysis for total testosterone, European and North American men, showed a stronger effect [-0.52 (95 % CI -0.75 to -0.3) P < 0.001].
CONCLUSIONS
Low-fat diets appear to decrease testosterone levels in men, but further randomised controlled trials are needed to confirm this effect. Men with European ancestry may experience a greater decrease in testosterone, in response to a low-fat diet.
Topics: Diet, Fat-Restricted; Diet, High-Fat; Dihydrotestosterone; Humans; Male; Sex Hormone-Binding Globulin; Testosterone
PubMed: 33741447
DOI: 10.1016/j.jsbmb.2021.105878 -
Journal of Cosmetic and Laser Therapy :... Jun 2024We aimed to determine the efficacy of the various available oral, topical, and procedural treatment options for hair loss in individuals with androgenic alopecia. Using...
We aimed to determine the efficacy of the various available oral, topical, and procedural treatment options for hair loss in individuals with androgenic alopecia. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic review of the National Library of Medicine was performed. Overall, 141 unique studies met our inclusion criteria. We demonstrate that many over the counter (e.g. topical minoxidil, supplements, low-level light treatment), prescription (e.g. oral minoxidil, finasteride, dutasteride), and procedural (e.g. platelet-rich plasma, fractionated lasers, hair transplantation) treatments successfully promote hair growth, highlighting the superiority of a multifaceted and individualized approach to management.
PubMed: 38852607
DOI: 10.1080/14764172.2024.2362126 -
Annals of Internal Medicine Jun 2024Whether circulating sex hormones modulate mortality and cardiovascular disease (CVD) risk in aging men is controversial. (Meta-Analysis)
Meta-Analysis Review
Associations of Testosterone and Related Hormones With All-Cause and Cardiovascular Mortality and Incident Cardiovascular Disease in Men : Individual Participant Data Meta-analyses.
BACKGROUND
Whether circulating sex hormones modulate mortality and cardiovascular disease (CVD) risk in aging men is controversial.
PURPOSE
To clarify associations of sex hormones with these outcomes.
DATA SOURCES
Systematic literature review to July 2019, with bridge searches to March 2024.
STUDY SELECTION
Prospective cohort studies of community-dwelling men with sex steroids measured using mass spectrometry and at least 5 years of follow-up.
DATA EXTRACTION
Independent variables were testosterone, sex hormone-binding globulin (SHBG), luteinizing hormone (LH), dihydrotestosterone (DHT), and estradiol concentrations. Primary outcomes were all-cause mortality, CVD death, and incident CVD events. Covariates included age, body mass index, marital status, alcohol consumption, smoking, physical activity, hypertension, diabetes, creatinine concentration, ratio of total to high-density lipoprotein cholesterol, and lipid medication use.
DATA SYNTHESIS
Nine studies provided individual participant data (IPD) (255 830 participant-years). Eleven studies provided summary estimates ( = 24 109). Two-stage random-effects IPD meta-analyses found that men with baseline testosterone concentrations below 7.4 nmol/L (<213 ng/dL), LH concentrations above 10 IU/L, or estradiol concentrations below 5.1 pmol/L had higher all-cause mortality, and those with testosterone concentrations below 5.3 nmol/L (<153 ng/dL) had higher CVD mortality risk. Lower SHBG concentration was associated with lower all-cause mortality (median for quintile 1 [Q1] vs. Q5, 20.6 vs. 68.3 nmol/L; adjusted hazard ratio [HR], 0.85 [95% CI, 0.77 to 0.95]) and lower CVD mortality (adjusted HR, 0.81 [CI, 0.65 to 1.00]). Men with lower baseline DHT concentrations had higher risk for all-cause mortality (median for Q1 vs. Q5, 0.69 vs. 2.45 nmol/L; adjusted HR, 1.19 [CI, 1.08 to 1.30]) and CVD mortality (adjusted HR, 1.29 [CI, 1.03 to 1.61]), and risk also increased with DHT concentrations above 2.45 nmol/L. Men with DHT concentrations below 0.59 nmol/L had increased risk for incident CVD events.
LIMITATIONS
Observational study design, heterogeneity among studies, and imputation of missing data.
CONCLUSION
Men with low testosterone, high LH, or very low estradiol concentrations had increased all-cause mortality. SHBG concentration was positively associated and DHT concentration was nonlinearly associated with all-cause and CVD mortality.
PRIMARY FUNDING SOURCE
Medical Research Future Fund, Government of Western Australia, and Lawley Pharmaceuticals. (PROSPERO: CRD42019139668).
Topics: Humans; Male; Cardiovascular Diseases; Testosterone; Sex Hormone-Binding Globulin; Estradiol; Cause of Death; Luteinizing Hormone; Dihydrotestosterone; Incidence; Risk Factors; Aged; Middle Aged
PubMed: 38739921
DOI: 10.7326/M23-2781 -
Clinical Biochemistry Dec 2017The aim of this study was to perform a systematic review of the published literature to determine the available serum/plasma steroid reference intervals generated by... (Review)
Review
The aim of this study was to perform a systematic review of the published literature to determine the available serum/plasma steroid reference intervals generated by mass spectrometry (MS) methods across all age groups in healthy subjects and to suggest recommendations to achieve common MS based reference intervals for serum steroids. MEDLINE, EMBASE and PubMed databases were used to conduct a comprehensive search for English language, MS-based reference interval studies for serum/plasma steroids. Selection of steroids to include was based on those listed in the Royal College of Pathologists of Australasia Quality Assurance Programs, Chemical Pathology, Endocrine Program. This methodology has been registered onto the PROSPERO International prospective register of systematic reviews (ID number: CRD42015029637). After accounting for duplicates, a total of 60 manuscripts were identified through the search strategy. Following critical evaluation, a total of 16 studies were selected. Of the 16 studies, 12 reported reference intervals for testosterone, 11 for 17 hydroxy-progesterone, nine for androstenedione, six for cortisol, three for progesterone, two for dihydrotestosterone and only one for aldosterone and dehydroepiandrosterone sulphate. No studies established MS-based reference intervals for oestradiol. As far as we are aware, this report provides the first comparison of the peer reviewed literature for serum/plasma steroid reference intervals generated by MS-based methods. The reference intervals based on these published studies can be used to inform the process to develop common reference intervals, and agreed reporting units for mass spectrometry based steroid methods.
Topics: Female; Humans; Male; Mass Spectrometry; Steroids
PubMed: 28733189
DOI: 10.1016/j.clinbiochem.2017.07.002 -
Cancer Causes & Control : CCC Aug 2022Observational studies and randomized controlled trials (RCTs) have shown an association between vitamin D levels and prostate cancer progression. However, evidence of... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
Observational studies and randomized controlled trials (RCTs) have shown an association between vitamin D levels and prostate cancer progression. However, evidence of direct causality is sparse and studies have not examined biological mechanisms, which can provide information on plausibility and strengthen the evidence for causality.
METHODS
We used the World Cancer Research Fund International/University of Bristol two-stage framework for mechanistic systematic reviews. In stage one, both text mining of published literature and expert opinion identified testosterone as a plausible biological mechanism. In stage two, we performed a systematic review and meta-analysis to assess the evidence from both human and animal studies examining the effect of vitamin D on testosterone, and testosterone on advanced prostate cancer (diagnostic Gleason score of ≥ 8, development of metastasis) or prostate cancer-specific mortality.
RESULTS
A meta-analysis of ten human RCTs showed evidence of an effect of vitamin D on total testosterone (standardised mean difference (SMD) = 0.133, 95% CI = - 0.003-0.269, I = 0.0%, p = 0.056). Five human RCTs showed evidence of an effect of vitamin D on free testosterone (SMD = 0.173, 95% CI = - 0.104-0.450, I = 52.4%, p = 0.220). Three human cohort studies of testosterone on advanced prostate cancer or prostate cancer-specific mortality provided inconsistent results. In one study, higher levels of calculated free testosterone were positively associated with advanced prostate cancer or prostate cancer-specific mortality. In contrast, higher levels of dihydrotestosterone were associated with lowering prostate cancer-specific mortality in another study. No animal studies met the study eligibility criteria.
CONCLUSION
There is some evidence that vitamin D increases levels of total and free testosterone, although the effect of testosterone levels within the normal range on prostate cancer progression is unclear. The role of testosterone as a mechanism between vitamin D and prostate cancer progression remains inconclusive.
Topics: Humans; Male; Prostate; Prostatic Neoplasms; Testosterone; Vitamin D; Vitamins
PubMed: 35752985
DOI: 10.1007/s10552-022-01591-w -
Journal of Clinical PsychopharmacologyFinasteride is one of several inhibitors of the 5α-reductase that converts testosterone to dihydrotestosterone used to treat hair loss and benign prostatic enlargement.... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Finasteride is one of several inhibitors of the 5α-reductase that converts testosterone to dihydrotestosterone used to treat hair loss and benign prostatic enlargement. Emerging clinical observations indicate that such treatment may be associated with depression, anxiety, and possibly increased suicidal risks, in addition to sexual dysfunction, even after its discontinuation.
METHODS
We carried out a systematic review of reports pertaining to association of finasteride treatment with clinical depression or other adverse psychiatric effects. We analyzed reported risks of depression by pooling of rates and by meta-analysis of comparisons of subjects treated with finasteride or not.
FINDINGS
Crude pooled rates of depressive symptoms with versus without finasteride were 3.33% (confidence interval, 3.22%-3.44%) versus 2.54% (2.44%-2.64%); random-effects meta-analysis yielded an odds ratio of 2.14 (1.40-3.27) (both P < 0.0001). In addition, risk of suicidal ideation or behavior was greater with versus without finasteride (21.2% [21.0%-21.5%] vs 14.0% [13.8%-14.2%], P < 0.0001), and risk of sustained sexual dysfunction was high (60.1% [37.3%-82.9%]).
CONCLUSIONS
The findings support a growing impression that finasteride is associated with adverse psychiatric effects that can persist in association with sexual dysfunction after discontinuing finasteride treatment.
Topics: 5-alpha Reductase Inhibitors; Alopecia; Depression; Finasteride; Humans; Male; Prostatic Hyperplasia; Sexual Dysfunction, Physiological; Suicidal Ideation
PubMed: 33814544
DOI: 10.1097/JCP.0000000000001379 -
The World Journal of Men's Health Oct 2020Since its discovery in December 2019, the novel coronavirus SARS-CoV-2 has spread globally, causing the current COVID-19 (coronavirus disease-19) pandemic. As there is...
PURPOSE
Since its discovery in December 2019, the novel coronavirus SARS-CoV-2 has spread globally, causing the current COVID-19 (coronavirus disease-19) pandemic. As there is an increase of infections in the male population, concerns have emerged about the potential impact of COVID-19 on male reproductive organs and male fertility. Therefore, this study systematically investigates the current evidence of SARS-CoV-2 impact on male reproduction and pregnancy outcomes, discussing them in light of the evidence published on other coronaviruses.
MATERIALS AND METHODS
Literature search was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 24 original articles were included for the analysis, investigating the effects of the infection on semen parameters, male reproductive hormones, and pregnancy outcomes. Further, a Strengths-Weaknesses-Opportunities-Threats (SWOT) analysis was conducted based on the available evidence linking the virus with male reproduction and conception.
RESULTS
Although there is limited data, viral mRNA has been identified in semen of infected men, with some evidence of altered seminal parameters. Low testosterone and dihydrotestosterone with raised luteinizing hormone has been reported as well as preterm delivery in pregnant women; however, data regarding vertical transmission remains contradictory and inconclusive.
CONCLUSIONS
The recent literature provides evidence that male gonads may be potentially vulnerable to SARS-CoV-2 infection, recommending caution to pregnant women and couples planning natural pregnancy or assisted reproduction.
PubMed: 32814369
DOI: 10.5534/wjmh.200134 -
BMC Medicine Nov 2014Potential cardiovascular (CV) risks of testosterone replacement therapy (TRT) are currently a topic of intense interest. However, no studies have addressed CV risk as a... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Potential cardiovascular (CV) risks of testosterone replacement therapy (TRT) are currently a topic of intense interest. However, no studies have addressed CV risk as a function of the route of administration of TRT.
METHODS
Two meta-analyses were conducted, one of CV adverse events (AEs) in 35 randomized controlled trials (RCTs) of TRT lasting 12 weeks or more, and one of 32 studies reporting the effect of TRT on serum testosterone and dihydrotestosterone (DHT).
RESULTS
CV risks of TRT: Of 2,313 studies identified, 35 were eligible and included 3,703 mostly older men who experienced 218 CV-related AEs. No significant risk for CV AEs was present when all TRT administration routes were grouped (relative risk (RR) = 1.28, 95% confidence interval (CI): 0.76 to 2.13, P = 0.34). When analyzed separately, oral TRT produced significant CV risk (RR = 2.20, 95% CI: 1.45 to 3.55, P = 0.015), while neither intramuscular (RR = 0.66, 95% CI: 0.28 to 1.56, P = 0.32) nor transdermal (gel or patch) TRT (RR = 1.27, 95% CI: 0.62 to 2.62, P = 0.48) significantly altered CV risk. Serum testosterone/DHT following TRT: Of 419 studies identified, 32 were eligible which included 1,152 men receiving TRT. No significant difference in the elevation of serum testosterone was present between intramuscular or transdermal TRT. However, transdermal TRT elevated serum DHT (5.46-fold, 95% CI: 4.51 to 6.60) to a greater magnitude than intramuscular TRT (2.20-fold, 95% CI: 1.74 to 2.77).
CONCLUSIONS
Oral TRT produces significant CV risk. While no significant effects on CV risk were observed with either injected or transdermal TRT, the point estimates suggest that further research is needed to establish whether administration by these routes is protective or detrimental, respectively. Differences in the degree to which serum DHT is elevated may underlie the varying CV risk by TRT administration route, as elevated serum dihydrotestosterone has been shown to be associated with CV risk in observational studies.
Topics: Administration, Cutaneous; Adult; Cardiovascular Diseases; Dihydrotestosterone; Hormone Replacement Therapy; Humans; Injections, Intramuscular; Male; Randomized Controlled Trials as Topic; Risk Factors; Testosterone
PubMed: 25428524
DOI: 10.1186/s12916-014-0211-5 -
Diagnostics (Basel, Switzerland) Aug 2023The aim of this systematic review is to provide a comprehensive overview of the role of fluoro-5α-dihydrotestosterone ([F]-FDHT) for the in vivo imaging of androgen... (Review)
Review
The aim of this systematic review is to provide a comprehensive overview of the role of fluoro-5α-dihydrotestosterone ([F]-FDHT) for the in vivo imaging of androgen receptors (AR) through positron emission tomography (PET) in metastatic breast (mBC) and metastatic castration-resistant prostate cancer (mCRPC). Relevant studies published from 2013 up to May 2023 were selected by searching Scopus, PubMed and Web of Science. The selected imaging studies were analyzed using a modified version of the critical Appraisal Skills Programme (CASP). Eleven studies encompassing 321 patients were selected. Seven of the eleven selected papers included 266 subjects (82.2%) affected by mCRPC, while four encompassed 55 (17.2%) patients affected by mBC. [F]-FDHT PET showed a satisfying test/retest reproducibility, and when compared to a histochemical analysis, it provided encouraging results for in vivo AR quantification both in mCRPC and mBC. [F]-FDHT PET had a prognostic relevance in mCRPC patients submitted to AR-targeted therapy, while a clear association between [F]-FDHT uptake and the bicalutamide response was not observed in women affected by AR-positive mBC. Further studies are needed to better define the role of [F]-FDHT PET, alone or in combination with other tracers (i.e., [F]-FDG/[F]-FES), for patients' selection and monitoring during AR-targeted therapy, especially in the case of mBC.
PubMed: 37568977
DOI: 10.3390/diagnostics13152613