Relationship between chronic pain and cognition in cognitively intact older persons and in patients with Alzheimer's disease. The need to control for mood.
BACKGROUND
Brain areas that are involved in cognition and mood also play a role in pain processing.


OBJECTIVE
The goal of the present study was to examine the relationship between chronic pain and cognition [executive functions (EF) and memory], while controlling for mood, in cognitively intact older persons and in patients with Alzheimer's disease (AD).


METHODS
Two groups of subjects participated: 20 older persons without dementia and 19 patients in an early stage of probable AD who suffered from arthrosis/arthritis. Pain intensity and pain affect were assessed by the Colored Analogue Scale for Pain Intensity and for Pain Affect, the Faces Pain Scale (FPS) and the Number of Words Chosen-Affective (NWC-A). Level of depression and anxiety were evaluated by questionnaires. EF and memory were assessed by neuropsychological tests.


RESULTS
The results show that significant correlations between specific cognitive functions, pain intensity and pain affect were lacking in the cognitively intact older persons. Cognition, in particular memory, appeared to be related to depressive symptoms. In contrast, a significant positive correlation was observed between EF, pain intensity and pain affect measured by the FPS in the AD group.


CONCLUSIONS
Although older persons with depression were excluded, in studies on pain and cognition one should control for the presence of depressive symptoms in older persons with and without dementia.
Scherder
Erik J A
EJ
Department of Clinical Neuropsychology, VU University Amsterdam, Amsterdam, The Netherlands. eja.scherder@psy.vu.nl
Eggermont
Laura
L
Plooij
Bart
B
Oudshoorn
Jeroen
J
Vuijk
Pieter Jelle
PJ
Pickering
Gisèle
G
Lautenbacher
Stefan
S
Achterberg
Wilco
W
Oosterman
Joukje
J
D000339:Affect; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000503:physiopathology / Q000523:psychology*; D016022:Case-Control Studies; D002908:Chronic Disease; D003071:Cognition; D003072:Cognition Disorders / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D010146:Pain / Q000523:psychology*; D010147:Pain Measurement / Q000379:methods / Q000523:psychology; D011795:Surveys and Questionnaires