Vitamin D Levels and Frontal Fibrosing Alopecia:

Do patients with FFA have lower vitamin D than other hair loss patients? Australian study says probably not

Vitamin D has an important role in the healthy functioning of the immune system.It is therefore important to understand the role of vitamin D in autoimmune and immune mediated hair loss conditions.

The role of vitamin D in frontal fibrosing alopecia (FFA) is not clear. If we think that FFA and LPP are similar, then we might hypothesize that patients with FFA might also have low vitamin D. For example, a 2021 study by Conic and colleagues showed that vitamin D deficiency is common in patients with LPP. In fact, patients with lichen planopilaris had an average vitamin D level of 24.6 ng/mL and this translated to an 8.3-fold increased odds of severe vitamin D deficiency compared with controls.

The role of vitamin D in FFA has not been carefully studied in the past.

Arasu et al, 2022

Arasu et al performed a retrospective study of patients with FFA seen in the clinic between March 2013 and February 2020. The baseline vitamin D levels in 100 women with FFA were compared with those in 100 women with female pattern hair loss (female androgenetic alopecia). Patients taking vitamin D supplementation were excluded.

About 20 % of patients with FFA and 20 % of patients with female androgenetic alopecia have suboptimal vitamin D levels. No patient in either group had severe vitamin D insufficiency. The mean 25- hydroxy vitamin D level in women with FFA was 68.9 nmol/L (27.6 ng/ml) compared with 65.96 nmol/L (26.4 ng/mL) in women with female pattern hair loss. There was no difference in vitamin D levels across different age groups such as less than 50, 50-59 and greater than 60.

All in all, the authors concluded that vitamin D levels in women with FFA did not differ from levels identified in women with androgenetic alopecia.

Comment

This is an important study for the books. At least in Australia, patients with FFA don’t seem to have lower vitamin D compared to patients with female pattern hair loss.

1) This study needs repeating. This study bears repeating in patients with FFA from other countries. I would not be surprised if a few studies popped up with different results in other countries with different baseline vitamin D status. The incidence of vitamin D deficiency is different in Australia than other countries. That may have relevance.

The nice thing about this study is that it included patients who were not using vitamin D. It’s a pretty rare thing to have FFA patients who don’t use vitamin D in Canada. Patients with FFA are often quite healthy and use vitamin D supplements, although with calcium.

2) A larger study may point to some findings. What would be important to understand is whether the severity of FFA impacts vitamin D status. It could be that more severe FFA is associated with different vitamin D levels than less severe FFA. Those studies will be important to do and will require a larger study to have enough patients to make meaningful conclusions.

3) What we can’t conclude here is that low vitamin D has no role in FFA. To do that, a different control group would be valuable. The important thing to remember here in this study is that low vitamin D levels are known to exist in patients with female pattern hair loss and low vitamin D is probably relevant to androgenetic alopecia pathogenesis. A 2021 review by Zubair and colleagues identified 13 relevant studies in the medical literature that that examined the relationship between low serum vitamin D levels and androgenetic alopecia. Patients with more severe androgenetic alopecia seemed to have lower vitamin D levels.

The authors of this study conclude that “there may be no additional requirement to measure vitamin D levels in patients with FFA compared to other forms of alopecia.” That seems true but one must not forget that measuring vitamin D is probably super important for other forms of alopecia. When we remember that the conclusion of this paper should really be written “ In patients with FFA, we probably need to measure vitamin D levels just like many other forms of alopecia and leaving this test out of the panel is probably a bad idea.

4) Vitamin D levels in FFA might not be all that different from LPP after all. Finally, it’s worth noting in this study that the average 25 OH vitamin D levels in FFA were 68.9 nmol/L (27.6 ng/mL). When we look back at studies of vitamin D in LPP we see that that Conic et al study put mean vitamin D in LPP at 61.4 nmol/L (24.6 ng/mL). It could be that FFA and LPP patient’s do not have dramatically different vitamin D status when all the proper controls are put in place (age, weight, obesity, diabetes, intake, latitude, etc)

REFERENCE

Arasu et al. Vitamin D status in patients with frontal fibrosing alopecia: A retrospective studyJAAD Int. 2022 Apr 18;7:129-130.

Conic RRZ et al. Vitamin D status in scarring and nonscarring alopecia. J Am Acad Dermatol. 2021;

Zubair Z et al. Prevalence of Low Serum Vitamin D Levels in Patients Presenting With Androgenetic Alopecia: A Review. Cureus 2021 Dec 15;13(12):e20431.