A comparison of serum zinc levels in melasma and non-melasma patients: a preliminary study of thyroid dysfunction.

Background: Melasma is an acquired hyperpigmentation disorder, clinically identified by symmetrical blackish-brown macules, especially on the facial area. Several factors are thought to play a role, including thyroid dysfunction and zinc deficiency. The aim of this study was to determine serum zinc levels in melasma and non-melasma patients with and without thyroid dysfunction.

Methods: A cross-sectional study was conducted in Jakarta in September 2019. There were 60 melasma patients and 60 non-melasma patients. The two groups were matched for age and sex. Atomic absorption spectrophotometry was used to measure serum zinc levels. Blood laboratory tests were used to check thyroid function by measuring thyroid stimulating hormone and free T4. Statistical analysis was performed using SPSS software.

Results: The mean serum zinc level in the melasma group was 10.25 ± 1.89 μmol/l and in the non-melasma group 10.29 ± 1.46 μmol/l (< 0.901). The mean serum zinc level in melasma patients with thyroid dysfunction was 8.77 ± 0.69 μmol/l, in melasma patients without thyroid dysfunction 10.33 ± 1.89 μmol/l, in non-melasma patients with thyroid dysfunction 10.48 ± 2.4 μmol/l, and in non-melasma patients without thyroid dysfunction 10.27 ± 1.4 μmol/l (< 0.184).

Conclusions: There was no significant difference between serum zinc levels in the melasma and non-melasma groups with and without thyroid dysfunction.