To examine a previously postulated relationship between chromosome loss (hypodiploidy) and mental impairment, 78 women ages 68 to 98 years (mean age 82.8) were selected from a New York State mental hospital and an institutional complex consisting of a nursing home, intermediate-care facility, and residence for the elderly.
Nursing home and state mental hospital patients showed a significantly higher frequency of chromosome loss than did the more intact women in the other two settings. There was a tendency, which did not reach statistical significance, for women with moderate or severe organic brain syndrome (OBS) diagnosis to have a greater percentage of hypodiploid cells than women with mild or no OBS.
Implications of these findings include the possibility that hypodiploidy rather than being purely detrimental may be an adaptation to aging.
Jarvik LF, Yen F. Chromosomes and Mental StatusA Study of Women Residing in Institutions for the Elderly. Arch Gen Psychiatry. 1974;30(2):186-190. doi:10.1001/archpsyc.1974.01760080046007