Selenium deficiency a factor in endemic goiter persistence in sub-Saharan Africa

Goiter is still common in Uganda, despite the present iodized salt coverage of at least 95%. Where there is endemic goiter after adequate iodine supplementation, selenium deficiency could be a factor for the continued occurrence of goiter. The objectives of the present study, therefore, were to determine the serum selenium levels among goitrous patients and nongoitrous controls and to determine the association between goiter and selenium levels among these patients.

The investigation was designed as a case control study in which 92 subjects were enrolled, 46 cases and 46 controls of similar age and sex distribution. Subjects were interviewed and examined. Blood samples were taken and selenium concentrations were determined by electrothermal atomic absorption spectrometry.

The overall mean serum selenium levels were 77.25 μg/l (SD 16.78) for the goiter patients and 95.50 μg/l (24.47) for the nongoiter controls. The difference between goitrous and nongoitrous populations was statistically significant (p=0.0001). Selenium levels above 102.8 μg/l had a statistically significant protective effect against goiter with adjusted odds ratio 0.3 (0.13-0.69); p=0.005. Other factors, such as age, main food constituent, and use of iodized salt, had no association with goiter.

There were significant differences between selenium levels among goitrous patients and nongoitrous controls. High selenium levels seem to have a protective effect against goiter. Selenium supplementation as a preventive strategy is worth further exploration.