title: Thyroid stimulating hormone and cognition during severe, transient hypothyroidism.
abstract: OBJECTIVE
  The purpose of our pilot study was to explore the relationship between serum thyroid stimulating hormone (TSH) levels during overt hypothyroidism (OH) and hypothyroid-related neuropsychological symptoms. We hypothesized that TSH level may reflect the degree of 'brain hypothyroidism' such that an inverse correlation may exist between serum TSH and cognitive function in patients experiencing overt hypothyroidism (OH), and sought to explore this hypothesis.
  
  
  METHODS
  Eleven thyroidectomized patients underwent neuropsychological and thyroid function testing while overtly hypothyroid, and again following thyroid hormone replacement. Their test performance was compared with that of eleven healthy controls at a similarly separated two points in time, and the change over time for the patient group and the controls was likewise assessed and compared. The patients' neuropsychological test scores were then correlated with their serum TSH levels while hypothyroid.
  
  
  RESULTS
  The patients' performance while hypothyroid was worse than that of the controls in only one neurocognitive measure--Working Memory Index. The subjects improved similarly or to a greater degree than the controls, when the subjects were thyroid hormone replaced, on all but one neurocognitive measure - Thurstone Word Fluency. TSH level during hypothyroidism was inversely proportional to the patients' performance on these same two measures, but no others.
  
  
  CONCLUSIONS
  Serum TSH level during hypothyroidism was inversely proportional to performance on the only two neurocognitive measures evidencing an adverse effect from hypothyroidism in our cohort. This suggests that serum TSH level may reflect the severity of 'brain hypothyroidism' during the overt stage of this condition.
authors.affiliation: Departments of Radiology and Psychiatry, Saint Joseph's Hospital and Medical Center/The Barrow Neurologic Institute, Phoenix, Arizona 85013, USA. fvschraml@yahoo.com
authors.forename: Frank V
authors.initials: FV
authors.lastname: Schraml
authors.forename: Pamela W
authors.initials: PW
authors.lastname: Goslar
authors.forename: Leslie
authors.initials: L
authors.lastname: Baxter
authors.forename: Lori L
authors.initials: LL
authors.lastname: Beason-Held
mesh_terms: D000328:Adult; D001007:Anxiety / Q000523:psychology; D003071:Cognition / Q000502:physiology*; D003627:Data Interpretation, Statistical; D003863:Depression / Q000523:psychology; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000503:physiopathology* / Q000523:psychology*; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects; D009483:Neuropsychological Tests; D010865:Pilot Projects; D011597:Psychomotor Performance / Q000502:physiology; D013960:Thyroid Function Tests; D013965:Thyroidectomy; D013972:Thyrotropin / Q000097:blood / Q000502:physiology*; D014145:Trail Making Test; D014705:Verbal Behavior / Q000502:physiology
chemical_list: D013972:Thyrotropin