Treatment of iron-deficiency anemia in patients with subclinical hypothyroidism.

OBJECTIVE Subclinical hypothyroidism is a health state that is associated with hypercholesterolemia, infertility, iron-deficiency anemia, and poor obstetric outcome. This article summarizes the results of a prospective clinical investigation of whether treatment of subclinical hypothyroidism and iron-deficiency anemia with a combination of levothyroxine plus iron salt would be superior to each treatment alone. METHODS In a randomized, double-blind, active-controlled trial, 60 patients with subclinical hypothyroidism and iron-deficiency anemia received iron salt+placebo (20 patients), levothyroxine+placebo (20 patients), or levothyroxine+iron salt (20 patients) for 3 months. Change from baseline (before) to end of study (after) in hemoglobin, ferritin, and thyroid-stimulating hormone levels were compared among groups. RESULTS The increase from baseline in hemoglobin and ferritin in the levothyroxine+iron group was superior to the other groups, in which a decrease in thyroid-stimulating hormone in the 2 groups that received levothyroxine was superior to the group treated with iron salt. CONCLUSION Subclinical hypothyroidism was investigated in iron-deficient patients with no acceptable response to iron salt alone. A combination of levothyroxine and iron salt is better than each one alone.