Several research articles have shown a positive association between psoriasis and thyroid diseases, including Hashimoto’s thyroiditis (hypothyroidism) and Grave’s disease (hyperthyroidism), but the limited number of studies do not provide a complete explanation to prove this association, according to a review study published in Cureus.
This review study included 45 articles that featured “psoriasis,” “hypothyroidism,” “thyroid function tests,” “propylthiouracil,” and “psoriatic arthritis” as inclusion keywords. Medical Subject Headings keywords “psoriasis,” “hypothyroidism,” and “autoimmunity” were also imputed into PubMed to identify the relevant articles for review.
A total of 39 of the 45 articles included in this review study demonstrated a positive association between psoriasis and thyroid diseases, although 6 articles found no association.
In 5 articles, researchers showed that thyroid hormones had an effect on the development of psoriasis. Other articles demonstrated that genetic, immunological, and inflammation were involved in the associations. Reactive oxygen species-related pathogenesis was also reported in 2 articles. In 5 articles, there were reports of positive thyroid peroxidase antibodies, thyroglobulin antibodies, and Hashimoto’s thyroiditis ultrasound features in patients with psoriasis.
Marked improvement was observed in psoriatic skin lesions following thyroidectomy in 2 articles. In addition, the investigators of this review found that first-line propylthiouracil for hyperthyroidism reportedly clears psoriatic lesions, according to findings in 6 articles. Propylthiouracil did not appear to induce clinical hypothyroidism or lead to any serious adverse effects. The researchers of this review study suggest propylthiouracil could be prescribed as an alternative therapy for patients with psoriasis due to its side effects compared with existing psoriasis treatments that are typically toxic and expensive.
The investigators also noted that a higher prevalence of the association between psoriasis and thyroid diseases in women was reported in some of the articles. However, some articles found no sex preference involved in the prevalence of the association.
Limitations of this study included the small number of articles available for review as well as the lack of a pooled meta-analysis of the data.
The investigators concluded that additional “studies are required to establish a connection between these diseases because these findings have a significant impact on both the clinical and research sides.”
Eapi S, Chowdhury R, Lawal OS, Mathur N, Malik BH. Etiological association between psoriasis and thyroid diseases. Cureus. 2021;13(1):e12653. Published 2021 Jan 12. doi:10.7759/cureus.12653