Selenium and zinc vs. chronic myofascial pain

The influence of selenium and zinc intake and concentrations of these minerals in serum and erythrocytes on the risk of chronic myofascial pain were analyzed using logistic regression. We showed an association between the concentration of Zn²⁺ in erythrocytes and pain, after the exclusion of serum and erythrocyte Se_T, serum Zn²⁺ and selenium intake. Hence, in each additional 1 mg of Zn²⁺ per gram of hemoglobin, a reduction of 12.5% was observed in the risk of the individual having chronic myofascial pain (B = -0.133; adjusted OR = 0.875, 95% CI = 0.803 to 0.954, Wald = 9.187, standard error = 0.044, p = 0.002). When the increment of erythrocyte Zn²⁺ (5 μgZn/gHb) was calculated, there was a 48.6% reduction in the risk of myofascial pain (OR = 0.514).