Background. Isolated TSH increase - „subclinical hypothyreosis“ (SH) appears to be comparatively common. Its
incidence among women over sixty has been estimated up to 17 %. Though SH was assumed to be entirely
asymptomatic, recent findings revealed various fine subjective and objective symptoms of the disease.
Methods and Results. Twenty otherwise healthy female patients with SH diagnosis were examined. Using
personality questionnaire MMPI/100 eight different clinical scales and two control scales were evaluated, using
Wechsler’s memory scale WM-R 5 memory quotients were tested. The group was randomised i nto a subgroup treated
for six month with placebo and a subgroup where thyroxin was administrated and thyroidal test normalised.
Psychological testing repeated before and after the treatment, results evaluated using paired t-test. Results indicate
that: 1. Patients with SH did not differ in personality features, they only had a higher tendency to the depressive
mood, which could be positively influenced by thyroxin (significance at 5 % level). 2. Thyroxin treatment brought
about improvement of some cognitive parameters of the verbal (p<0.01), visual (p<0.05), and general memory
(p<0.01). 3. Results of psychological and cognitive tests correlate better with FT4 than TSH level.
Conclusions. Though SH cannot be associated with changes in personality features, TSH normalisation results in
statistically significant improvement of cognitive function - verbal, visual and general memory.
subclinical hypothyreosis, neuro-psychological investigation, thyroxin treatment.