title: Cognitive function in subclinical hypothyroidism in elderly.
abstract: OBJECTIVE
  To study the association of cognitive function with subclinical hypothyroidism in elderly.
  
  
  METHODS
  It's a cross-sectional, case-control study of 103 patients (≥65 years) who met the criteria for subclinical hypothyroidism. Similarly 103 age, sex and education-matched healthy controls were taken. Serum TSH, free T3 and free T4 were measured. Cognitive functions were assessed by using Folstein Mini Mental Examination (MMSE) and clock drawing test.
  
  
  RESULTS
  Out of the 103 diagnosed subclinical hypothyroidism cases, cognitive impairment (by MMSE) was found in 33 (30.9%) while it was present in only 15 (14.54%) out of 103 controls (P = 0.003), cognitive impairment (by CDT) was present in 32 patients (31.06%) out of 103 cases while it was present in 26 patients (25.24%) out of 103 controls (P > 0.05, insignificant). Mean TSH of subclinical hypothyroidism with cognitive impairment was 7.67 ± 1.22 mIU/liter and without cognitive impairment was 6.47 ± 0.98 mIU/liter (P value = 0.0001, significant).
  
  
  CONCLUSIONS
  Prevalence of cognitive impairment was significantly higher in subclinical hypothyroidism as compared to controls. Presence of cognitive impairment correlated with the level of TSH; as TSH increased cognitive function declined.
authors.affiliation: Department of Medicine, Swaroop Rani Nehru Hospital, Allahabad, Uttar Pradesh, India.
authors.forename: Sarita
authors.initials: S
authors.lastname: Bajaj
authors.affiliation: Department of Medicine, Swaroop Rani Nehru Hospital, Allahabad, Uttar Pradesh, India.
authors.forename: Shivam
authors.initials: S
authors.lastname: Sachan
authors.affiliation: Department of Pathology, Moti Lal Nehru Medical College, Allahabad, Uttar Pradesh, India.
authors.forename: Vatsala
authors.initials: V
authors.lastname: Misra
authors.affiliation: Department of Medicine, Swaroop Rani Nehru Hospital, Allahabad, Uttar Pradesh, India.
authors.forename: Anurag
authors.initials: A
authors.lastname: Varma
authors.affiliation: Department of Medicine, Swaroop Rani Nehru Hospital, Allahabad, Uttar Pradesh, India.
authors.forename: Piyush
authors.initials: P
authors.lastname: Saxena
keywords: Cognitive impairment; elderly; subclinical hypothyroidism