{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T02:48:58Z","timestamp":1791600538541,"version":"4.3.4"},"reference-count":28,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T00:00:00Z","timestamp":1791331200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T00:00:00Z","timestamp":1791331200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004587","name":"Instituto de Salud Carlos III","doi-asserted-by":"publisher","award":["PI23\/01590"],"award-info":[{"award-number":["PI23\/01590"]}],"id":[{"id":"10.13039\/501100004587","id-type":"DOI","asserted-by":"publisher"}]},{"award":["PI23\/01590"],"award-info":[{"award-number":["PI23\/01590"]}],"id":[{"id":"https:\/\/ror.org\/00ca2c886","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Clin. Med.","JCM"],"abstract":"<jats:p>Background\/Objectives: Frontal fibrosing alopecia (FFA) and lichen planopilaris (LPP) are primary lymphocytic cicatricial alopecias with frequently reported systemic and dermatological comorbidities, although their prevalence and consistency across studies remain uncertain. Methods: We conducted a systematic review and random-effects prevalence meta-analysis following PRISMA 2020 and Joanna Briggs Institute guidance, prospectively registered in PROSPERO (CRD420250656067). MEDLINE, Embase, ClinicalTrials.gov, preprint sources, and reference lists were searched from inception to 18 June 2025 for observational studies reporting comorbidity prevalence in FFA and\/or LPP. Results: Sixty studies comprising 4499 patients with FFA and 1370 with LPP were included. In FFA, the highest pooled prevalences among commonly reported conditions included androgenetic alopecia (31.9%), hypertension (23.6%), thyroid disorders (22.2%), hypothyroidism (20.6%), lichen planus pigmentosus (19.6%), and dyslipidemia (17.9%). In LPP, androgenetic alopecia (27.2%), hypertension (21.2%), hypothyroidism (18.7%), vitamin D deficiency (18.3%), dyslipidemia (16.0%), and thyroid disorders (14.5%) were prominent. Several estimates showed substantial between-study heterogeneity. Exploratory subgroup analyses identified study-level sources of heterogeneity for selected outcomes, whereas no meta-regression association remained significant after false-discovery-rate correction. Conclusions: These findings provide a quantitative map of comorbidity burden in FFA and LPP and support targeted, individualized clinical assessment. Because this analysis estimates prevalence within affected populations rather than comparative risk against controls, the findings should not be interpreted as evidence of excess risk or causal relationships.<\/jats:p>","DOI":"10.3390\/jcm15197728","type":"journal-article","created":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T01:40:17Z","timestamp":1791596417000},"page":"7728","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Comorbidity Burden in Frontal Fibrosing Alopecia and Lichen Planopilaris: A Systematic Review and Prevalence Meta-Analysis"],"prefix":"10.3390","volume":"15","author":[{"given":"Juan Luis","family":"Sanz-Cabanillas","sequence":"first","affiliation":[{"name":"Inflammatory Immune-Mediated Skin Diseases Laboratory (GC29), Maimonides Biomedical Research Institute of C\u00f3rdoba (IMIBIC), University of C\u00f3rdoba, 14004 C\u00f3rdoba, Spain"},{"name":"Department of Dermatology, Reina Sof\u00eda University Hospital, 14004 C\u00f3rdoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francisco Jos\u00e9","family":"G\u00f3mez-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Inflammatory Immune-Mediated Skin Diseases Laboratory (GC29), Maimonides Biomedical Research Institute of C\u00f3rdoba (IMIBIC), University of C\u00f3rdoba, 14004 C\u00f3rdoba, Spain"},{"name":"Department of Dermatology, Reina Sof\u00eda University Hospital, 14004 C\u00f3rdoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena Beatriz","family":"Sanz-Cabanillas","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Reina Sof\u00eda University Hospital, 14004 C\u00f3rdoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7223-1922","authenticated-orcid":false,"given":"Jes\u00fas","family":"Gay-Mimbrera","sequence":"additional","affiliation":[{"name":"Inflammatory Immune-Mediated Skin Diseases Laboratory (GC29), Maimonides Biomedical Research Institute of C\u00f3rdoba (IMIBIC), University of C\u00f3rdoba, 14004 C\u00f3rdoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio Jos\u00e9","family":"V\u00e9lez Garc\u00eda-Nieto","sequence":"additional","affiliation":[{"name":"Inflammatory Immune-Mediated Skin Diseases Laboratory (GC29), Maimonides Biomedical Research Institute of C\u00f3rdoba (IMIBIC), University of C\u00f3rdoba, 14004 C\u00f3rdoba, Spain"},{"name":"Department of Dermatology, Reina Sof\u00eda University Hospital, 14004 C\u00f3rdoba, Spain"},{"name":"Department of Medical and Surgical Sciences, Faculty of Medicine and Nursing, University of C\u00f3rdoba, 14004 C\u00f3rdoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beatriz","family":"Isla-Tejera","sequence":"additional","affiliation":[{"name":"Inflammatory Immune-Mediated Skin Diseases Laboratory (GC29), Maimonides Biomedical Research Institute of C\u00f3rdoba (IMIBIC), University of C\u00f3rdoba, 14004 C\u00f3rdoba, Spain"},{"name":"Department of Pharmacy, Reina Sof\u00eda University Hospital, 14004 C\u00f3rdoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0286-4107","authenticated-orcid":false,"given":"Juan","family":"Ruano","sequence":"additional","affiliation":[{"name":"Inflammatory Immune-Mediated Skin Diseases Laboratory (GC29), Maimonides Biomedical Research Institute of C\u00f3rdoba (IMIBIC), University of C\u00f3rdoba, 14004 C\u00f3rdoba, Spain"},{"name":"Department of Dermatology, Reina Sof\u00eda University Hospital, 14004 C\u00f3rdoba, Spain"},{"name":"Department of Medical and Surgical Sciences, Faculty of Medicine and Nursing, University of C\u00f3rdoba, 14004 C\u00f3rdoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,10,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1016\/j.ad.2016.11.012","article-title":"Update on frontal fibrosing alopecia","volume":"108","author":"Requena","year":"2017","journal-title":"Actas Dermosifiliogr."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"100113","DOI":"10.1016\/j.xjidi.2022.100113","article-title":"Frontiers in lichen planopilaris and frontal fibrosing alopecia research: Pathobiology progress and translational horizons","volume":"2","author":"Senna","year":"2022","journal-title":"JID Innov."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Rivera-Ruiz, I., Ungar, B., D\u00e1vila-Flores, V., Gay-Mimbrera, J., G\u00f3mez-Arias, P.J., Juan-Cencerrado, M., Moch\u00f3n-Jim\u00e9nez, C., Parra-Peralbo, E., Isla-Tejera, B., and L\u00f3pez-Vi\u00f1au L\u00f3pez, T. (2025). Unravelling the transcriptomic landscape of primary lymphocytic scarring alopecias: Systematic review and meta-analysis. Front. Immunol., 16.","DOI":"10.3389\/fimmu.2025.1651019"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1067\/mjd.2003.68","article-title":"Summary of North American Hair Research Society (NAHRS)-sponsored workshop on cicatricial alopecia, Duke University Medical Center, February 10 and 11, 2001","volume":"48","author":"Olsen","year":"2003","journal-title":"J. Am. Acad. Dermatol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"770","DOI":"10.1001\/archderm.1994.01690060100013","article-title":"Postmenopausal frontal fibrosing alopecia. Scarring alopecia in a pattern distribution","volume":"130","author":"Kossard","year":"1994","journal-title":"Arch. Dermatol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"186","DOI":"10.1002\/jvc2.50","article-title":"The spectrum of fibrosing alopecias","volume":"1","author":"Orlando","year":"2022","journal-title":"JEADV Clin. Pract."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1246","DOI":"10.1111\/ijd.17780","article-title":"Delphi consensus on the distinct clinical and histopathological features of lichen planopilaris and frontal fibrosing alopecia: Insights from the Hair Diseases Task Force","volume":"64","author":"Starace","year":"2025","journal-title":"Int. J. Dermatol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1083","DOI":"10.1111\/bjd.19040","article-title":"Frontal fibrosing alopecia shows robust T helper 1 and Janus kinase 3 skewing","volume":"183","author":"Pavel","year":"2020","journal-title":"Br. J. Dermatol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1111\/exd.13816","article-title":"IL-17-positive mast cell infiltration in the lesional skin of lichen planopilaris: Possible role of mast cells in inducing inflammation and dermal fibrosis in cicatricial alopecia","volume":"29","author":"Hobo","year":"2020","journal-title":"Exp. Dermatol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"104486","DOI":"10.1016\/j.ad.2025.104486","article-title":"Spanish Working group on trichology and onychology. Consensus document on the clinical management of frontal fibrosing alopecia: Recommendations from Spanish Working Group on Trichology and Onychology of the AEDV","volume":"117","author":"Combalia","year":"2026","journal-title":"Actas Dermosifiliogr."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2257","DOI":"10.1111\/ijd.17925","article-title":"Comorbidities associated with lichen planopilaris: A systematic review and meta-analysis","volume":"64","author":"Chen","year":"2025","journal-title":"Int. J. Dermatol."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Yongpisarn, T., Tejapira, K., and Suchonwanit, P. (2025). Comorbidities in primary cicatricial alopecia: A systematic review and meta-analysis. Front. Immunol., 16.","DOI":"10.3389\/fimmu.2025.1516407"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"210","DOI":"10.1111\/jdv.20833","article-title":"Statement from the frontal fibrosing alopecia international expert alliance: 2024","volume":"40","author":"Meah","year":"2026","journal-title":"J. Eur. Acad. Dermatol. Venereol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1059","DOI":"10.1016\/j.jaad.2024.10.126","article-title":"Frontal fibrosing alopecia (FFA) part I: Diagnosis and clinical presentation","volume":"94","author":"Alenezi","year":"2026","journal-title":"J. Am. Acad. Dermatol."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Roman, A.M., Petca, R.C., Dumitra\u0219cu, M.C., Petca, A., Ionescu Miron, A.I., and \u0218andru, F. (2024). Frontal fibrosing alopecia and reproductive health: Assessing the role of sex hormones in disease development. J. Pers. Med., 14.","DOI":"10.3390\/jpm14010072"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1097\/XEB.0000000000000054","article-title":"Methodological guidance for systematic reviews of observational epidemiological studies reporting prevalence and cumulative incidence data","volume":"13","author":"Munn","year":"2015","journal-title":"Int. J. Evid. Based Healthc."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"4","DOI":"10.21037\/aot.2020.02.02","article-title":"Lichen planopilaris and thyroid disease: Systematic review and meta-analysis","volume":"5","author":"Phan","year":"2020","journal-title":"Ann. Thyroid."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1093\/ced\/llae446","article-title":"Association of lichen planopilaris with cardiovascular and metabolic disorders: A systematic review and meta-analysis","volume":"50","author":"Chuang","year":"2025","journal-title":"Clin. Exp. Dermatol."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Aromataris, E., Lockwood, C., Porritt, K., Pilla, B., and Jordan, Z. (2024). JBI Manual for Evidence Synthesis, JBI.","DOI":"10.46658\/JBIMES-24-01"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"123","DOI":"10.15171\/ijhpm.2014.71","article-title":"The development of a critical appraisal tool for use in systematic reviews addressing questions of prevalence","volume":"3","author":"Munn","year":"2014","journal-title":"Int. J. Health Policy Manag."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"n71","DOI":"10.1136\/bmj.n71","article-title":"The PRISMA 2020 statement: An updated guideline for reporting systematic reviews","volume":"372","author":"Page","year":"2021","journal-title":"BMJ"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1539","DOI":"10.1002\/sim.1186","article-title":"Quantifying heterogeneity in a meta-analysis","volume":"21","author":"Higgins","year":"2002","journal-title":"Stat. Med."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"974","DOI":"10.1136\/jech-2013-203104","article-title":"Meta-analysis of prevalence","volume":"67","author":"Barendregt","year":"2013","journal-title":"J. Epidemiol. Community Health"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"611","DOI":"10.1111\/ced.14190","article-title":"Lichen planopilaris and dyslipidaemia: Systematic review and meta-analysis","volume":"45","author":"Phan","year":"2020","journal-title":"Clin. Exp. Dermatol."},{"key":"ref_25","first-page":"1099","article-title":"A cross-sectional study of rosacea and risk factors in women with frontal fibrosing alopecia","volume":"99","year":"2019","journal-title":"Acta Derm. Venereol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"e13560","DOI":"10.1111\/dth.13560","article-title":"Allergic contact dermatitis in patients with frontal fibrosing alopecia: An international multi-center study","volume":"33","author":"Rudnicka","year":"2020","journal-title":"Dermatol. Ther."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"922","DOI":"10.1111\/j.1600-0560.2007.00937.x","article-title":"Involvement of the bulge region in primary scarring alopecia","volume":"35","author":"Pozdnyakova","year":"2008","journal-title":"J. Cutan. Pathol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"551","DOI":"10.1016\/j.jaad.2021.05.016","article-title":"Scalp and serum profiling of frontal fibrosing alopecia reveals scalp immune and fibrosis dysregulation with no systemic involvement","volume":"86","author":"Dubin","year":"2022","journal-title":"J. Am. Acad. Dermatol."}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/19\/7728\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T01:54:24Z","timestamp":1791597264000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/19\/7728"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,10,7]]},"references-count":28,"journal-issue":{"issue":"19","published-online":{"date-parts":[[2026,10]]}},"alternative-id":["jcm15197728"],"URL":"https:\/\/doi.org\/10.3390\/jcm15197728","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,10,7]]}}}