ABSTRACT
In observational studies, elderly persons who
had participated to a greater extent in leisure ac-
tivities had a lower risk o f dementia than those who
had participated to a lesser extent.10'15 Although
these results suggest that leisure activities have a
protective role, an alternative explanation is possi-
ble. In m ost types o f dementia, there is a long pe-
riod o f cognitive decline preceding diagnosis.16'18
Reduced participation in activities during this pre-
clinical phase o f dementia may be the consequence
and not the cause o f cognitive decline. Resolution
o f this issue requires a long period o f observation
before diagnosis to enable researchers to disen-
tangle the potential effects o f preclinical dementia.
Base-line cognitive status, educational level, and
