G. Manciet et al., THE PAQUID SURVEY AND CORRELATES OF SUBCLINICAL HYPOTHYROIDISM IN ELDERLY COMMUNITY RESIDENTS IN THE SOUTH-WEST OF FRANCE, Age and ageing, 24(3), 1995, pp. 235-241
The aim of this study was to assess the prevalence of increased thyroi
d-stimulating hormone (TSH) levels (subclinical or undiagnosed hypothy
roidism) in a representative sample of a community-living elderly popu
lation and to examine the relationships with cognitive functions and d
epressive symptoms. An epidemiological study was made of a cohort of 2
792 subjects over 65 years of age. A blood sample was obtained from 42
5 volunteers of this cohort and assayed for TSH. Every subject partici
pating in the study was interviewed and given a battery of neuropsycho
logical tests by a psychologist. Three hundred and eighty-one subjects
(89.7%) had normal TSH levels; 18 subjects (4.2%) had TSH lower than
0.4 mu U/ml, associated in two of them with hyperthyroxinaemia. Twenty
-six subjects (6.1%) had increased TSH levels, associated in 18 of the
m with a normal free thyroxine level and in eight with a low free thyr
oxine level. Increased TSH levels were significantly linked with femal
e sex and with the presence of symptoms of depression on the CES-D sca
le but not with impairment of cognitive function.