Serum Iodine and Bromine in Chronic Hemodialysis Patients—An Observational Study in a Cohort of Portuguese Patients

Background: Patients on chronic hemodialysis therapy are at high risk of disturbances in trace element status due to both the underlying disease and the hemodialysis process itself. Data on iodine and bromine levels in these patients are scarce. Methods: Using an ICP-MS analytical procedure, serum iodine and bromine levels were determined in a cohort (n = 57) of end-stage renal disease patients on chronic hemodialysis. The results were compared with those of a control group (n = 59). Results: Hemodialysis patients presented serum iodine levels within the normal range, slightly lower than in controls, but without reaching a statistically significant difference (67.6 ± 17.1 µg/L vs. 72.2 ± 14.8 µg/L; p = 0.1252). In contrast, serum bromine levels were much lower in patients (1086 ± 244 µg/L vs. 4137 ± 770 µg/L; p < 0.0001), at values only about 26% of the values observed in controls. Conclusions: Hemodialysis patients had normal serum iodine levels, but highly decreased serum bromine levels. The clinical significance of this finding requires further investigation, but it may be associated with sleep disturbances and fatigue that affect hemodialysis patients.