The effect of vitamin D recommendations on serum 25-hydroxyvitamin D level in patients with erythropoietic protoporphyria

• Published in: Nutrition (Burbank, Los Angeles County, Calif.) Vol. 93; p. 111477
• Main Authors: Heerfordt, Ida M., Lerche, Catharina M., Philipsen, Peter A., Wulf, Hans Christian
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.01.2022; Elsevier Limited
• Subjects: 25(OH)D; 25-Hydroxyvitamin D; Blood tests; Calcifediol; Calciferol; Chromatography; Counseling; Dermatology; Dietary Supplements; Erythropoietic protoporphyria; Gender differences; Humans; Intervention; Liver diseases; Patients; Photosensitivity; Population; Protoporphyria, Erythropoietic - drug therapy; Seasons; Skin; Sun exposure; Supplements; Vitamin D; Vitamin D - analogs & derivatives; Vitamin D Deficiency - complications; Vitamin D Deficiency - drug therapy; Vitamin deficiency; Winter; Womens health; Denmark; 25(OH)D; Skin; Vitamin D; Sun exposure; Erythropoietic protoporphyria; Supplements
• ISSN: 0899-9007; 1873-1244
• DOI: 10.1016/j.nut.2021.111477

•Patients with erythropoietic protoporphyria (EPP) experience skin photosensitivity.•Patients with EPP avoid sun exposure and often lack vitamin D.•Danish patients with EPP are in general recommended daily vitamin D supplements all year.•Personal vitamin D counseling was given if vitamin D was low.•We found a positive effect of the recommendations on vitamin D status in patients with EPP. Patients with erythropoietic protoporphyria (EPP) avoid sun exposure owing to photosensitivity. For decades, sun-avoiding Danes have been recommended daily vitamin D supplements all year. We offered our EPP patients serum 25-hydroxyvitamin D (25(OH)D) monitoring, and counseling if their level was low. We aimed to investigate the effect of the general recommendation and counseling on 25(OH)D status in patients attending our clinic. Additionally, the 25(OH)D status of our EPP patients was compared to that of British patients with EPP not taking vitamin D supplements and with that of the general Danish population. Forty-six Danish patients with EPP had 25(OH)D measured in 721 blood samples collected between 2003 and 2021. Dates of individual counseling were noted. Data on British patients with EPP and the general Danish population were extracted from previous publications. Our patients had higher 25(OH)D levels than British patients with EPP not taking vitamin D supplements, but the recommendations did not elevate their 25(OH)D levels to that of the general Danish population. Overall, 17.5% of the 25(OH)D measurements in our EPP patients were below 30 nmol/L (deficiency) and 29.4% were between 30 and 50 nmol/L (insufficiency). Patients were monitored for a median of 11 y. Thirty-one patients had a total of 74 vitamin D counseling sessions, providing an increase in 25(OH)D of about 18 nmol/L the year after. However, many patients repeatedly developed insufficiency. This study documents the positive effect of vitamin D recommendations on serum 25(OH)D in patients with EPP. Follow-up on vitamin D status and recommendations is essential to increase 25(OH)D levels.