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

Abstract

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 B12 in patients with rosacea. Objective. To investigate serum Hcy, vitamin B12, 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 B12, and folic acid were measured. A correlation was assessed between disease severity and serum levels of Hcy, vitamin B12, and folic acid. Results. Serum vitamin B12 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 B12 deficiency in patients with PPR.