Relationships of Serum Homocysteine, Vitamin B12, and Folic Acid Levels with Papulopustular Rosacea Severity: A Case-Control Study

Background. Rosacea is a chronic inflammatory skin disease with a multifactorial etiology. Recently, associations between serum homocysteine (Hcy) levels and inflammatory skin diseases, such as psoriasis and hidradenitis suppurativa, have been reported. However, no study has explored the levels of serum Hcy, folic acid, and vitamin B-12 in patients with rosacea. Objective. To investigate serum Hcy, vitamin B-12, and folic acid levels in patients with papulopustular rosacea (PPR), we characterized the association of these levels with PPR severity. Methods. This case-control study included 138 PPR patients and 58 healthy controls. The serum levels of Hcy, vitamin B-12, and folic acid were measured. A correlation was assessed between disease severity and serum levels of Hcy, vitamin B-12, and folic acid. Results. Serum vitamin B-12 and folic acid levels were significantly lower in PPR patients than in the healthy controls (p = 0.011 and p = 0.0173, respectively). Although serum Hcy levels did not significantly differ between PPR patients and healthy controls, PPR severity was positively correlated with serum Hcy levels (p < 0.001). Conclusions. Our results suggest a possible association between hyperhomocysteinemia and vitamin B-12 deficiency in patients with PPR.