Association of lichen planopilaris with hypothyroidism: a systematic review and meta‐analysis
Notice bibliographique
Résumé
Lichen planopilaris (LPP) is a variant of lichen planus characterized by T-lymphocyte-mediated perifollicular inflammation leading to irreversible, scarring alopecia. It has an estimated prevalence between 0.03 and 0.04%.1, 2 Given the autoimmune pathophysiology of LPP, several recent studies have analyzed the association between LPP and autoimmune diseases, namely hypothyroidism. However, an association between LPP and hypothyroidism has been inconsistently reported in the literature, with studies both supporting3 and refuting4 such an association. Here, we analyze the association between LPP and hypothyroidism in meta-analysis. We performed a systematic review of the literature, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and registered our protocol via PROSPERO (CRD42023422790). We searched EMBASE and MEDLINE from their dates of inception to April 2023 using the keywords “comorbidities,” “hypothyroidism,” “lichen planopilaris,” and “thyroid.” We included case–control studies that assessed the prevalence of LPP among cases and controls. Abstracts, case reports, case series, and cross-sectional studies without a control group were excluded. Study quality was assessed using the Newcastle–Ottawa scale. We calculated pooled odds ratio (OR) using a random effects model and evaluated study heterogeneity using the I2 statistic; publication bias was assessed using the Egger test. All analyses were performed using MedCalc software (version 20.305). Our initial search yielded 1,029 unique references; seven studies met our inclusion criteria, with a total of 1,664 LPP patients (Figure 1). Four studies reported positive, statistically significant associations between LPP and hypothyroidism, two studies demonstrated positive but statistically insignificant associations, and one study showed a negative, statistically insignificant association. Meta-analysis demonstrated an increased prevalence of hypothyroidism in LPP patients compared with controls (OR = 1.75, 95% CI: 1.46–2.21, P = 0.001, I2 = 57.4%). Egger test revealed nonsignificant publication bias (P = 0.76; Figure 2). Per the Newcastle–Ottawa scale, all studies (evaluated by two authors – TPJ and SK) were found to be of good quality. At present, the precise link between LPP and hypothyroidism remains to be elucidated, though several hypotheses may explain this association. As a T-lymphocyte-mediated process, LPP may share dysregulated T-cell/cytokine pathways with hypothyroidism. Such a hypothesis has been advanced to explain the association between alopecia areata and hypothyroidism.5 Additionally, there may be potentially overlapping human leukocyte antigen (HLA) restriction between LPP and hypothyroidism, causing aberrant licensing of T cells that attack both thyroid tissue and hair follicles. Limitations of our analysis include the inability to evaluate LPP severity or establish temporality between a diagnosis of hypothyroidism and LPP. Additionally, as only two of the seven studies presented disaggregated data by LPP subtype (i.e., LPP and frontal fibrosing alopecia), we were unable to perform subgroup analysis. We acknowledge that it would be valuable to study the association between hypothyroidism and LPP with stratification by LPP subtype. While LPP and frontal fibrosing alopecia are both T-cell-mediated diseases, potential differences in HLA variants associated with LPP or frontal fibrosing alopecia may impact the propensity of developing hypothyroidism. Nonetheless, our metanalysis is the first to report a link between LPP and hypothyroidism. Given this association, dermatologists may wish to elicit a thyroid review of systems when evaluating patients with LPP. Furthermore, patients with LPP may benefit from establishing care with a primary care physician and formal thyroid function studies, if indicated.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,006 | 0,001 |
| Bibliométrie | 0,001 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».