Background: Divergences in cognitive disturbances in hypothyroidism
reported in the literature are a result of a methodological bias. Methods:
By using a precise methodology, we examined attention and executive
functions in hypothyroidism, verified the presence of anxiety and
depressive symptoms in hypothyroidism, and examined the possible link
between these symptoms and the cognitive disturbances (searching for
attentional bias for words with a negative emotional valence). We
administered a battery of cognitive tests to 23 participants who had
undergone thyroidectomy for thyroid carcinoma: for the first time in an
euthyroid state, then 3 weeks later (still in the euthyroid state) to
assess the test/retest effect, and finally 4 weeks later in an
hypothyroid state. We compared their performance with that of a group of
26 control participants who were also administered the same cognitive
tests, also 3 times. Results: In hypothyroidism, the thyroid participants
were more anxious and depressed than the controls and presented
attentional and executive disturbances that reflected general slowing and
difficulties in using their capacities of inhibition. However, they did
not exhibit an attentional bias for words with a negative emotional
valence. Conclusions: Contrary to what was expected, symptoms of anxiety
and not symptoms of depression interfered with the cognitive performance
of participants in hypothyroidism. (JINS, 2005, 11,
535–544.)