Global InformationPattern hair loss information
| Pattern hair loss | |
|---|---|
| Other names | Male pattern baldness; female pattern baldness; androgenic alopecia; androgenetic alopecia; alopecia androgenetica |
 | |
| Male-pattern hair loss shown on the vertex of the scalp | |
| Specialty | Dermatology, plastic surgery |
Pattern hair loss (also known as androgenetic alopecia (AGA)[1]) is a hair loss condition that primarily affects the top and front of the scalp.[2][3] In male-pattern hair loss (MPHL), the hair loss typically presents itself as either a receding front hairline, loss of hair on the crown (vertex) of the scalp, or a combination of both. Female-pattern hair loss (FPHL) typically presents as a diffuse thinning of the hair across the entire scalp.[3]
Genetic research has identified alleles associated with male pattern hair loss. [4] These alleles appear to be undergoing positive sexual selection in European and East Asian populations, as male pattern baldness may be seen as a masculine attribute associated with seniority and higher social status.[4] The condition is caused by a combination of male sex hormones (balding never occurs in castrated men) and genetic factors.[5]
Some research has found evidence for the role of oxidative stress in hair loss,[6] the microbiome of the scalp,[7][8] genetics, and circulating androgens; particularly dihydrotestosterone (DHT).[3] Men with early onset androgenic alopecia (before the age of 35) have been deemed the male phenotypic equivalent for polycystic ovary syndrome (PCOS).[9][10][11][12]
The cause in female pattern hair loss remains unclear;[3] androgenetic alopecia for women is associated with an increased risk of polycystic ovary syndrome (PCOS).[13][14][15]
Management may include simply accepting the condition[3] or shaving one's head to improve the aesthetic aspect of the condition.[16] Otherwise, common medical treatments include minoxidil, finasteride, dutasteride, or hair transplant surgery.[3] Use of finasteride and dutasteride in women is not well-studied and may result in birth defects if taken during pregnancy.[3]
By the age of 50, pattern hair loss affects about half of males and a quarter of females.[3] It is the most common cause of hair loss. Both males aged 40–91[17] and younger male patients of early onset AGA (before the age of 35), had a higher likelihood of metabolic syndrome (MetS)[18][19][20][21] and insulin resistance.[22] With younger males, studies found metabolic syndrome to be at approximately a 4× increased frequency which is clinically deemed significant.[23][24] Abdominal obesity, hypertension and lowered high density lipoprotein were also significantly higher for younger groups.[25]
- ^ "Androgenetic alopecia". National Library of Medicine, Bethesda, Maryland, United States. 1 August 2015. Archived from the original on 9 November 2020. Retrieved 3 April 2022.
- ^ Wang EH, Monga I, Sallee BN, Chen JC, Abdelaziz AR, Perez-Lorenzo R, et al. (Jul 2022). "Primary cicatricial alopecias are characterized by dysregulation of shared gene expression pathways". PNAS Nexus. 1 (3): pgac111. doi:10.1093/pnasnexus/pgac111. PMC 9308563. PMID 35899069.
- ^ a b c d e f g h Vary JC (November 2015). "Selected Disorders of Skin Appendages--Acne, Alopecia, Hyperhidrosis". The Medical Clinics of North America (Review). 99 (6): 1195–1211. doi:10.1016/j.mcna.2015.07.003. PMID 26476248.
- ^ a b Cite error: The named reference
Hillmer Freudenberg Myles Herms 2009 pp. 255–264was invoked but never defined (see the help page). - ^ Randall VA (2012-07-26). "Androgens and hair: a biological paradox with clinical consequences". Testosterone. Cambridge University Press. pp. 154–176. doi:10.1017/cbo9781139003353.008. ISBN 978-1-139-00335-3.
Male pattern baldness is androgen dependent, since it does not occur in castrates, unless they are given testosterone (Hamilton 1942), nor in XY individuals with androgen insensitivity due to non-functional androgen receptors (see Chapter 3). The genetic involvement in androgenetic alopecia is also pronounced.
- ^ Cite error: The named reference
pmid34668238was invoked but never defined (see the help page). - ^ Suzuki K, Inoue M, Cho O, Mizutani R, Shimizu Y, Nagahama T, et al. (2021). "Scalp Microbiome and Sebum Composition in Japanese Male Individuals with and without Androgenetic Alopecia". Microorganisms. 9 (10): 2132. doi:10.3390/microorganisms9102132. PMC 8536999. PMID 34683453.
- ^ Huang J, Ran Y, Pradhan S, Yan W, Dai Y (2019). "Investigation on Microecology of Hair Root Fungi in Androgenetic Alopecia Patients". Mycopathologia. 184 (4): 505–515. doi:10.1007/s11046-019-00345-8. PMID 31240449. S2CID 195353938.
- ^ Cannarella R, La Vignera S, Condorelli RA, Calogero AE (2017). "Glycolipid and Hormonal Profiles in Young Men with Early-Onset Androgenetic Alopecia: A meta-analysis". Scientific Reports. 7 (1): 7801. Bibcode:2017NatSR...7.7801C. doi:10.1038/s41598-017-08528-3. PMC 5552767. PMID 28798373.
- ^ Sanke S, Chander R, Jain A, Garg T, Yadav P (2016). "A Comparison of the Hormonal Profile of Early Androgenetic Alopecia in Men with the Phenotypic Equivalent of Polycystic Ovarian Syndrome in Women". JAMA Dermatology. 152 (9): 986–991. doi:10.1001/jamadermatol.2016.1776. PMID 27304785. S2CID 26897074.
- ^ Krysiak R, Kowalcze K, Okopień B (2022). "Impaired metabolic effects of metformin in men with early-onset androgenic alopecia". Pharmacological Reports. 74 (1): 216–228. doi:10.1007/s43440-021-00347-8. PMC 8786753. PMID 34897595.
- ^ Cite error: The named reference
prematpcoswas invoked but never defined (see the help page). - ^ Goodman NF, Cobin RH, Futterweit W, Glueck JS, Legro RS, Carmina E, et al. (2015). "American Association of Clinical Endocrinologists, American College of Endocrinology, and Androgen Excess and Pcos Society Disease State Clinical Review: Guide to the Best Practices in the Evaluation and Treatment of Polycystic Ovary Syndrome--Part 1". Endocrine Practice. 21 (11): 1291–1500. doi:10.4158/EP15748.DSC. PMID 26509855.
- ^ Camacho-Martínez FM (2009). "Hair loss in women". Seminars in Cutaneous Medicine and Surgery. 28 (1): 19–32. doi:10.1016/j.sder.2009.01.001. PMID 19341939.
- ^ Moura HH, Costa DL, Bagatin E, Sodré CT, Manela-Azulay M (2011). "Polycystic ovary syndrome: A dermatologic approach". Anais Brasileiros de Dermatologia. 86 (1): 111–119. doi:10.1590/s0365-05962011000100015. PMID 21437531.
- ^ Dunn R (2012). "Why haven't bald men gone extinct?". New Scientist. 214 (2869): 44–47. Bibcode:2012NewSc.214...44D. doi:10.1016/s0262-4079(12)61567-x. Archived from the original on June 27, 2012. Retrieved Dec 16, 2012.
- ^ Su LH, Chen TH (2010). "Association of androgenetic alopecia with metabolic syndrome in men: A community-based survey". The British Journal of Dermatology. 163 (2): 371–377. doi:10.1111/j.1365-2133.2010.09816.x. PMID 20426781. S2CID 23615726.
- ^ Ertas R, Orscelik O, Kartal D, Dogan A, Ertas SK, Aydogdu EG, et al. (2016). "Androgenetic alopecia as an indicator of metabolic syndrome and cardiovascular risk". Blood Pressure. 25 (3): 141–148. doi:10.3109/08037051.2015.1111021. PMID 26585114. S2CID 12031777.
- ^ Dharam Kumar KC, Kishan Kumar YH, Neladimmanahally V (2018). "Association of Androgenetic Alopecia with Metabolic Syndrome: A Case-control Study on 100 Patients in a Tertiary Care Hospital in South India". Indian Journal of Endocrinology and Metabolism. 22 (2): 196–199. doi:10.4103/ijem.IJEM_650_17. PMC 5972473. PMID 29911030.
- ^ Bakry OA, Shoeib MA, El Shafiee MK, Hassan A (2014). "Androgenetic alopecia, metabolic syndrome, and insulin resistance: Is there any association? A case-control study". Indian Dermatology Online Journal. 5 (3): 276–281. doi:10.4103/2229-5178.137776. PMC 4144211. PMID 25165643.
- ^ Banger HS, Malhotra SK, Singh S, Mahajan M (2015). "Is Early Onset Androgenic Alopecia a Marker of Metabolic Syndrome and Carotid Artery Atherosclerosis in Young Indian Male Patients?". International Journal of Trichology. 7 (4): 141–147. doi:10.4103/0974-7753.171566. PMC 4738480. PMID 26903742.
- ^ Acibucu F, Kayatas M, Candan F (2010). "The association of insulin resistance and metabolic syndrome in early androgenetic alopecia". Singapore Medical Journal. 51 (12): 931–936. PMID 21221497.
- ^ Sheikh FZ, Butt G, Hafeez R, Maqsood A, Altaf F, Hussain I (2021). "Association of Early-onset Androgenetic Alopecia and Metabolic Syndrome". Journal of the College of Physicians and Surgeons (Pakistan). 31 (2): 123–127. doi:10.29271/jcpsp.2021.02.123. PMID 33645175. S2CID 232079822.
- ^ Pengsalae N, Tanglertsampan C, Phichawong T, Lee S (2013). "Association of early-onset androgenetic alopecia and metabolic syndrome in Thai men: A case-control study". Journal of the Medical Association of Thailand = Chotmaihet Thangphaet. 96 (8): 947–951. PMID 23991602.
- ^ Gopinath H, Upadya GM (2016). "Metabolic syndrome in androgenic alopecia". Indian Journal of Dermatology, Venereology and Leprology. 82 (4): 404–408. doi:10.4103/0378-6323.174421. PMID 27279298. S2CID 24300999.