Alopecia androgénica masculina y factores de riesgo cardiovascular: estudio de casos y controles

Association between metabolic syndrome and prevalent skin diseases: A systematic review and meta-analysis of case-control studies

Background and Aim

Metabolic syndrome (MetS) is a well-known noncommunicable disease that plays a significant role in emerging other chronic disorders and following complications. MetS is also involved in the pathophysiology of numerous dermatological diseases. We aim to evaluate the association of MetS with the most prevalent dermatological diseases.

Methods

A systematic search was carried out on PubMed, Science Direct, Web of Science, Cochrane, as well as the Google Scholar search engine. Only English case-control studies regarding MetS and any skin disease from the beginning of 2010 up to November 15, 2022, were selected. The study was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA).

Results

A total of 37 studies (13,830 participants) met the inclusion criteria. According to our result, patients with psoriasis, hidradenitis suppurativa (HS), vitiligo, androgenetic alopecia (AGA), and lichen planus (LP) have a higher chance of having MetS compared to the general population. Furthermore, people with seborrheic dermatitis (SED) and rosacea are more prone to insulin resistance, high blood pressure (BP), and higher blood lipids. After pooling data, the meta-analysis revealed a significant association between MetS and skin diseases (pooled odds ratio [OR]: 3.28, 95% confidence interval: 2.62-4.10). Concerning the type of disease, MetS has been correlated with AGA (OR: 11.86), HS (OR: 4.46), LP (OR: 3.79), and SED (OR: 2.45). Psoriasis also showed a significant association but with high heterogeneity (OR: 2.89). Moreover, skin diseases and MetS are strongly associated in Spain (OR: 5.25) and Thailand (OR: 11.86). Regarding the metaregression model, the effect size was reduced with increasing age (OR: 0.965), while the size increased with AGA (OR: 3.064).

Conclusions

MetS is closely associated with skin complications. Dermatologists and other multidisciplinary teams should be cautious while treating these patients to prevent severe complications resulting from MetS.

Cholesterol homeostasis in hair follicle keratinocytes is disrupted by impaired ABCA5 activity

The importance of cholesterol in hair follicle biology is underscored by its links to the pathogenesis of alopecias and hair growth disorders. Reports have associated defects in ABCA5, a membrane transporter, with altered keratinocyte cholesterol distribution in individuals with a form of congenital hypertrichosis, yet the biological basis for this defect in hair growth remains unknown. This study aimed to determine the impact of altered ABCA5 activity on hair follicle keratinocyte behaviour. Primary keratinocytes isolated from the outer root sheath of plucked human hair follicles were utilised as a relevant cell model. Following exogenous cholesterol loading, an increase in ABCA5 co-localisation to intracellular organelles was seen. Knockdown of ABCA5 revealed a dysregulation in cholesterol homeostasis, with LXR agonism leading to partial restoration of the homeostatic response. Filipin staining and live BODIPY cholesterol immunofluorescence microscopy revealed a reduction in endo-lysosomal cholesterol following ABCA5 knockdown. Analysis of oxysterols showed a significant increase in the fold change of 25-hydroxycholesterol and 7-β-hydroxycholesterol following cholesterol loading in ORS keratinocytes, after ABCA5 knockdown. These data suggest a role for ABCA5 in the intracellular compartmentalisation of free cholesterol in primary hair follicle keratinocytes. The loss of normal homeostatic response, following the delivery of excess cholesterol after ABCA5 knockdown, suggests an impact on LXR-mediated transcriptional activity. The loss of ABCA5 in the hair follicle could lead to impaired endo-lysosomal cholesterol transport, impacting pathways known to influence hair growth. This avenue warrants further investigation.

Association Between Androgenic Alopecia and Coronary Artery Disease: A Cross-Sectional Study of Han Chinese Male Population

Purpose

This research aimed to investigate the correlation between androgenic alopecia (AGA) and coronary artery disease (CAD) and analyze its value in predicting the severity of coronary atherosclerosis in the Han Chinese male population.

Patients and Methods

A total of 402 Han Chinese male patients aged 28-75 years were enrolled and performed coronary angiography (CAG) after admission. According to the BASP classification, the participants were divided into mild, moderate and severe AGA. CAD was determined via CAG and defined as stenosis of ≥50% in at least one major coronary artery, and the Gensini score was calculated to evaluate the severity of coronary atherosclerosis.

Results

In this study, CAD status (P = 0.002), dyslipidemia status (P = 0.002), age (P = 0.003) and coronary atherosclerosis severity (P < 0.001) were different in patients with different levels of AGA. Multivariate logistic regression analysis revealed that severe AGA was independently correlated to CAD risk (OR, 2.111; 95% CI 1.152 to 3.870, P = 0.016), while the relative CAD risk of early-onset AGA was 2.292 (OR, 2.292; 95% CI 1.132 to 4.640, P = 0.021). AGA status (OR, 2.247; 95% CI 1.396 to 3.617, P = 0.001), severe AGA (OR, 2.360; 95% CI 1.506 to 3.699, P < 0.001) and early-onset AGA (OR, 3.474; 95% CI 2.069 to 5.832, P < 0.001) were all independently associated with the severity of coronary atherosclerosis. The area under the receiver operating characteristic (ROC) curve plotted using severe AGA was 0.601, which is predictive of severe coronary atherosclerosis. Moreover, the presence of severe AGA increases the risk of developing CAD associated with obesity (SI = 1.663, SIM = 1.222, AP = 0.289), diabetes (SI = 2.239, SIM = 1.149, AP = 0.503) and dyslipidemia (SI = 1.062, SIM = 0.646, AP = 0.045).

Conclusion

This study suggested that AGA is independently associated with CAD in a Han Chinese male population. AGA may be a simple and feasible method for screening CAD and indicative of the severity of coronary atherosclerosis.

Skin and metabolic syndrome: A review of the possible associations

Metabolic syndrome (MeTS) is a well-known health-related problem with several end-organ damages and the resulted side effects such as rising in the blood glucose and lipid and blood pressure. Although MeTS might show several skin symptoms such as acanthosis nigricans, skin tags, acne, and androgenic alopecia, it could also be implicated in the pathophysiology of numerous dermatologic disorders. Furthermore, some dermatologic drugs might be implicated in the incidence or exacerbation of MeTS. Consequently, MeTS and skin problem could interfere closely with each other and each one could predispose the patient to the other one and vice versa. Remembering these close relationships help us to have better therapeutic choices regarding each inflammatory skin conditions. Moreover, some of the skin symptoms should be followed cautiously to define the underlying MeTS.

Clinical, trichoscopic, and folliscopic identification of the impact of metabolic syndrome on the response to intradermal dutasteride 0.02% injection in patients with female pattern hair loss: a prospective cohort study

BACKGROUND

No studies investigating the impact of metabolic syndrome (MetS) in treatment response of female pattern hair loss (FPHL).

OBJECTIVE

In this prospective cohort study, we studied the impact of MetS in response to intradermal dutasteride 0.02% injection in patients with FPHL.

METHODS

Fifty-one adult participants with FPHL were classified into study cohorts: with MetS and comparison cohorts without MetS. Both groups underwent clinical, trichoschopic, and digital folliscopic evaluation. Treatment was scheduled over a period of 3 months as four weekly sessions, followed by another four bimonthly sessions. Response was evaluated by digital folliscopy, investigator's, and patient's self assessments at 1 and 3 months post-treatment. Side effects were evaluated.

RESULTS

In participants with MetS, there was a significant reduction of the mean percentage of terminal hair with significant increase of the mean percentage of vellus hair (p = .003, .006, respectively) compared with participants without MetS at 1 month after treatment. These significant differences persisted at 3 months after treatment; for terminal and vellus hair (p = .000) with significant reduction in the mean hair thickness (p = .002) compared with participants without MetS.

CONCLUSIONS

MetS negatively impacted FPHL in terms of response to intradermal injection of dutasteride 0.02% and severity. Further studies are still needed.

Cholesterol homeostasis: Links to hair follicle biology and hair disorders

Lipids and lipid metabolism are critical factors in hair follicle (HF) biology, and cholesterol has long been suspected of influencing hair growth. Altered cholesterol homeostasis is involved in the pathogenesis of primary cicatricial alopecia, mutations in a cholesterol transporter are associated with congenital hypertrichosis, and dyslipidaemia has been linked to androgenic alopecia. The underlying molecular mechanisms by which cholesterol influences pathways involved in proliferation and differentiation within HF cell populations remain largely unknown. As such, expanding our knowledge of the role for cholesterol in regulating these processes is likely to provide new leads in the development of treatments for disorders of hair growth and cycling. This review describes the current state of knowledge with respect to cholesterol homeostasis in the HF along with known and putative links to hair pathologies.

Does a male polycystic ovarian syndrome equivalent exist?

The occurrence of a genetic background in the etiology of polycystic ovarian syndrome (PCOS) represents the rational basis to postulate the existence of a male PCOS equivalent. Hormonal and metabolic abnormalities have been described in male relatives of women with PCOS. These males also have a higher prevalence of early onset (<35 years) androgenetic alopecia (AGA). Hence, this feature has been proposed as a clinical sign of the male PCOS equivalent. Clinical evidence has shown that men with early onset AGA have hormonal and metabolic abnormalities. Large cohort studies have clearly shown a higher prevalence of type II diabetes mellitus (DM II) and cardiovascular diseases (CVDs) in elderly men with early onset AGA. In addition, prostate cancer, benign prostate hyperplasia (BPH) and prostatitis have been described. These findings support the existence of the male PCOS equivalent, which may represent an endocrine syndrome with a metabolic background, and might predispose to the development of DM II, CVDs, prostate cancer, BPH and prostatitis later in life. Its acknowledgment would be helpful for the prevention of these long-term complications.

Androgenic alopecia, premature graying, and hair thinning as independent predictors of coronary artery disease in young Asian males

We herewith aimed to explore the association of premature graying, androgenic alopecia (AGA), and hair thinning with coronary artery disease (CAD) in young (≤40 years) male individuals from Western India.

Patients and methods

In this prospective, case-control study, 1380 male individuals from a super speciality cardiac care center were enrolled, of which 468 were established cases of CAD and 912 were age-matched healthy male individuals not having history of any major illness including CAD. Details of demographics, cardiovascular risk factors, and cutaneous markers were collected for both the groups.

Results

Prevalence of hypertension (30.3 vs. 13.6%), obesity (28.8 vs. 12.2%), hair thinning (36.3 vs. 14.6%), premature graying (49.6 vs. 29.9%), AGA (49.1 vs. 27.4%), and lipid abnormalities (total cholesterol - 16.7 vs. 8.8%; low-density lipoprotein - 7.3 vs. 2.2%; and high-density lipoprotein - 92.5 vs. 88.7%) were higher in cases as compared with control. Multiple logistic regression analysis showed that AGA [5.619, 95% confidence interval (CI): 4.025-7.845, P<0.0001] is the strongest predictor of CAD among young Asian male individuals, closely followed by premature graying (5.267, 95% CI: 3.716-7.466, P<0.0001), obesity (4.133, 95% CI: 2.839-6.018, P<0.0001), and hair thinning (3.36, 95% CI: 2.452-4.621, P<0.0001). SYNTAX score, left ventricle ejection fraction, and degree of disease severity were also found to be independent associates of premature graying and AGA.

Conclusion

Our findings support the hypothesis that cutaneous markers are independently associated with underlying CAD irrespective of other classical cardiovascular risk factors. This, in combination with classical markers, could be effectively used for early identification and risk stratification of young patients with occult or established CAD.

Alopecia and the metabolic syndrome

Hair loss is a common condition that affects most people at some point in their lives. It can exist as an isolated problem or with other diseases and conditions. Androgenetic alopecia (AGA) and its association with the metabolic syndrome (MetS) have received increasing interest since 1972, when the first link between cardiovascular risk factors and hair loss was raised. We have reviewed studies concerning the relationship between alopecia and MetS. Many studies have investigated the relationship among AGA and MetS and its individual components, particularly in men, where a disproportionately large number of these studies supports this association. AGA has also been associated with other metabolic-related conditions, including coronary artery disease, polycystic ovary syndrome, and Cushing syndrome, as well as several nutritional deficiencies, all of which have led to many clinicians advocating for the screening of MetS and cardiovascular risk factors in patients who present with AGA.

Glycolipid and Hormonal Profiles in Young Men with Early-Onset Androgenetic Alopecia: A meta-analysis

Hormonal and metabolic abnormalities have been reported in men with early-onset androgenetic alopecia (AGA). Although this has been ascribed to the existence of a male polycystic ovary syndrome (PCOS)-equivalent, data on this topic are inconsistent and this syndrome has not been already acknowledged. To evaluate if, already before the age of 35 years, any difference occurs in the glycolipid and hormonal profiles and in the body weight in men with AGA compared to age-matched controls, we performed a comprehensive meta-analysis of all the available observational case-control studies of literature, using MEDLINE, Google Schoolar and Scopus databases. Among 10596 papers retrieved, seven studies were finally included, enrolling a total of 1009 participants. Our findings demonstrate that young men with AGA have a slightly but significantly worse glycolipid profile compared to controls and a hormonal pattern resembling those of women with PCOS, already before the age of 35 years. Therefore, early-onset AGA might represent a phenotypic sign of the male PCOS-equivalent. The acknowledgement of this syndrome would be of importance to prevent the long-term consequences on health in the affected men. The glycolipid profile and the body weight should be monitored in men with AGA starting from the second decade of life.

Inflammatory markers and Lp(a) levels as cardiovascular risk factors in androgenetic alopecia

It is not well-established whether patients with androgenetic alopecia (AGA) show a higher cardiovascular risk and higher prevalence of metabolic syndrome (MS). Therefore, we aimed to analyze the cardiovascular risk and the prevalence of MS by means of a case-control study. We determined lipidic, inflammatory, hormonal and insulin resistance parameters with conventional laboratory methods in 50 male early-onset AGA patients and 50 controls. AGA patients did not show statistical differences for insulin resistance (glucose, insulin, C peptide, HOMA), lipids (total-cholesterol, HDL-cholesterol, tryglicerides) or hormonal parameters (testosterone, free androgen index, sex hormone-binding globulin) P >  0.05, respectively. No differences between groups were observed in prevalence of MS or its components (P >  0.05). AGA patients showed higher levels of fibrinogen, C-reactive protein (CRP) and lipoprotein(a) (Lp(a)) (P = 0.016, P = 0.019 and P = 0.032, respectively). In the unadjusted logistic regression analyses, PCR >4 mg/L, fibrinogen >395 mg/dL and Lp(a) >59 mg/dL increased the risk of AGA, but in the adjusted logistic regression analyses, only PCR >4 mg/L and Lp(a) >59 mg/dL independently increased this risk (OR = 5.83, 95% CI 1.33-25.59 P = 0.020; OR = 3.94 CI 95% 1.08-14.43 P = 0.038). The present study indicates that AGA patients do not show differences in either insulin resistance or prevalence of MS. However, AGA patients show a higher cardiovascular risk characterised by an increase in inflammatory parameters and Lp(a) levels.

[New populations at increased cardiovascular risk: Cardiovascular disease in dermatological diseases]

The increased cardiovascular risk in some dermatological diseases has been demonstrated in recent decades. Diseases such as psoriasis and systemic lupus erythematosus are currently included in the guidelines for prevention of cardiovascular disease. Other diseases such as androgenic alopecia, polycystic ovary syndrome, hidradenitis suppurativa or lichen planus have numerous studies that point to an increased risk, however, they have not been included in these guidelines. In this article we review the evidence supporting this association, in order to alert the clinician to the need for greater control in cardiovascular risk factors in these patients.

Relationship between androgenetic alopecia and cardiovascular risk factors according to BASP classification in Koreans

There have been many studies on the relationship between androgenetic alopecia (AGA) and cardiovascular risk factors, but the study results were inconsistent and research on AGA in Asians remains insufficient. This study investigated the relationship between Korean AGA and various cardiovascular risk factors, considering life habits, type of hair loss and sex. We investigated subjects who visited a hospital for public or industrial health medical examinations between October 2012 and December 2014. A questionnaire as well as anthropometric measurements and a blood test were performed. Among the 1884 total subjects, 52.6% had AGA. AGA patients displayed a significantly higher prevalence rate of cardiovascular diseases, smoking rate, fasting glucose and triglyceride, and a significantly lower high-density lipoprotein cholesterol level than did the non-AGA group. The results of the subgroup analysis showed higher prevalence rates of hypertension, stroke, metabolic syndrome and smoking in male AGA patients. The more severe the AGA, the higher the incidences of hypertension, diabetes and smoking were observed. According to the analysis results by BASP classification, the F-type AGA patients displayed a higher body mass index, waist circumference and diastolic blood pressure, and had a significantly higher prevalence rate of hypertension. As a result of the large population-based study, modifications in lifestyle and early screening for cardiovascular disease, as well as hypertension and diabetes, are suggested.

Benign prostatic hyperplasia, metabolic syndrome and androgenic alopecia: Is there a possible relationship?

OBJECTIVE

To evaluate the incidence of benign prostatic hyperplasia (BPH) and metabolic syndrome in patients with androgenetic alopecia (AGA) in comparison with those with no AGA, as several previous studies have reported inconsistent results of an association between metabolic syndrome and BPH with AGA.

PATIENTS SUBJECTS AND METHODS

This cross-sectional study included 400 participants, divided into 300 patients diagnosed with AGA, with different grades according to Norwood-Hamilton classification, and 100 control subjects with no AGA. Criteria for diagnosis of metabolic syndrome according to Adult Treatment Panel-III criteria (waist circumference, blood pressure, fasting blood sugar, high-density lipoprotein and triglycerides), as well as criteria for diagnosis of BPH (prostatic volume, urine flow, and prostate-specific antigen) were assessed in all patients and compared with the control subjects.

RESULTS

There were significant differences between the AGA and no-AGA groups for the following variables: waist circumference, body mass index, fibrinogen level, fasting blood sugar, cholesterol, C-reactive protein, erythrocyte sedimentation rate, and glycosylated haemoglobin. There was a significant difference in number of patients with AGA manifesting criteria of metabolic syndrome (51% vs 28%), as well as BPH diagnostic criteria (36% vs 6.8%) compared with the control subjects. Both BPH and metabolic syndrome were shown to be significant independent variables associated with AGA.

CONCLUSIONS

Dermatologists, urologists, and primary care physicians should monitor patients with early onset AGA for the development of urinary symptoms, to permit an earlier diagnosis of BPH; and for metabolic syndrome symptoms, to permit early diagnosis of cardiovascular risk factors.

Alopecia and its association with coronary heart disease and cardiovascular risk factors: a meta-analysis

BACKGROUND

Alopecia has been associated with an increased risk of coronary heart disease as well as the following risk factors for cardiovascular disease: hyperinsulinaemia, insulin resistance, metabolic syndrome, dyslipidaemia, and hypertension. We performed a meta-analysis to quantitatively determine the level of risk of coronary heart disease and risk factors in individuals with alopecia.

METHODS

A systematic literature search was conducted using several databases. We calculated pooled odds ratios and 95% confidence intervals using a random effects model.

RESULTS

In total, 31 studies comprising 29,254 participants with alopecia were eligible for the meta-analysis and showed that alopecia is associated with an increased risk of coronary heart disease (OR 1.22, 95% CI: 1.07-1.39), hyperinsulinaemia (OR 1.97, 95% CI: 1.20-3.21), insulin resistance (OR 4.88, 95% CI: 2.05-11.64), and metabolic syndrome (OR 4.49, 95% CI: 2.36-8.53). Individuals with alopecia were also shown to be more likely compared to those without alopecia to have higher serum cholesterol levels (OR 1.60, 95% CI: 1.17-2.21), higher serum triglyceride levels (OR 2.07, 95% CI: 1.32-3.25), higher systolic blood pressures (OR 1.73, 95% CI: 1.29-2.33), and higher diastolic blood pressures (OR 1.59, 95% CI: 1.16-2.18).

CONCLUSIONS

Alopecia is associated with an increased risk of coronary heart disease, and there appears to be a dose-response relationship with degree of baldness whereby the greater the severity of alopecia, the greater the risk of coronary heart disease. Alopecia is also associated with an increased risk of hypertension, hyperinsulinaemia, insulin resistance, metabolic syndrome, and having elevated serum total cholesterol and triglyceride levels.

Androgenetic alopecia as an early marker of benign prostatic hyperplasia

BACKGROUND

Androgenetic alopecia (AGA) and benign prostatic hyperplasia are both androgen-dependent entities that respond to the blocking of 5-alpha-reductase.

OBJECTIVES

The objective of this study was to determine whether prostatic volumes and urinary flow changes were higher in patients with early-onset AGA than in healthy control subjects.

METHODS

This was an observational case-control study of 87 men: 45 with early-onset AGA diagnosed in the dermatology department and 42 control subjects. End-point variables were prostatic volume, measured by transrectal ultrasound, and urinary flow, measured by urinary flowmetry. A hormone study was performed on all participants, and the International Prostate Symptom Score and International Index of Erectile Function score were determined.

RESULTS

The groups did not significantly differ in mean age (cases, 52.7 years vs control subjects, 49.8 years; P = .12). Patients with AGA had significantly higher mean prostate volume (29.65 vs 20.24 mL, P < .0001), International Prostate Symptom Score (4.93 vs 1.23, P < .0001), and prostate-specific antigen value (1.53 vs 0.94 ng/mL, P < .0001) and significantly lower maximum urinary flow (14.5 vs 22.45 mL/s, P < .0001) versus control subjects. Binary logistic regression analysis showed a strong association between the presence of AGA and benign prostatic hyperplasia after adjusting for age, urinary volume, urination time, International Prostate Symptom Score, abdominal obesity, glucose levels, systolic blood pressure, insulin levels, fibrinogen, and C-reactive protein (odds ratio = 5.14, 95% confidence interval 1.23-47.36, P = .041).

LIMITATIONS

The study of larger sample sizes would facilitate stratified analyses according to the Ebling type of androgenetic alopecia.

CONCLUSION

There is a relationship between the presence of AGA and prostate growth-associated urinary symptoms, likely attributable to their pathophysiological similarity. This study suggests that early-onset AGA may be an early marker of urinary/prostatic symptomatology. Future studies may clarify whether treatment of patients with AGA may benefit the concomitant benign prostatic hypertrophy, which would be present at an earlier stage in its natural evolution.