Autonomic, Behavioral, and Subjective Pain Responses in Alzheimer's Disease.
OBJECTIVE
To compare autonomic, behavioral, and subjective pain responses of patients with Alzheimer's disease (AD) to those of healthy seniors (HS). As few studies have examined patients with severe Alzheimer's disease (sAD), we emphasized inclusion of these patients together with mild/moderate Alzheimer's disease (mAD) patients to characterize pain responses potentially affected by disease severity.


METHODS
A controlled cross-sectional study involving repeated measures behavioral pain testing.


METHODS
An outpatient clinical setting and local nursing facilities.


METHODS
Community dwelling HS controls (N = 33) and individuals with chart-confirmed diagnoses of AD (N = 38, Diagnostic and Statistical Manual-IV criteria).


METHODS
HS and AD groups were compared in their responses to repeated applications of five pressure intensities (1-5 kg) on the distal forearm. Autonomic responses (heart rate [HR]), pain behaviors (vocal, facial, and bodily as scored by the Pain Assessment in Advanced Dementia [PAINAD] scale), and subjective pain ratings (Faces Pain Scale-Revised) were measured.


RESULTS
HR responses to pressure stimuli were differentially affected based on AD severity: sAD patients had generally decreased HR reactivity compared with other groups (P < 0.01). In contrast, pain behaviors were increased in AD regardless of severity (P < 0.001), compared with HS, for all but the lowest pressure intensity. Increased behaviors occurred in all measured domains of the PAINAD (P < 0.005). While sAD were unreliable subjective reporters, mAD patients (N = 17) rated low level pressures as more painful than HS (P < 0.01).


CONCLUSIONS
These findings provide behavioral and subjective-report evidence of increased acute pain sensitivity in AD, which should be taken into consideration with respect to pain management across the spectrum of AD severity.
Michigan State University College of Osteopathic Medicine, DO/PhD Training Program, East Lansing, Michigan, USA.|Michigan State University Neuroscience Program, East Lansing, Michigan, USA.
Paul A
PA
Beach
Michigan State University Neuroscience Program, East Lansing, Michigan, USA.
Jonathan T
JT
Huck
Michigan State University College of Human Medicine, East Lansing, Michigan, USA.
Melodie M
MM
Miranda
Michigan State University Neuroscience Program, East Lansing, Michigan, USA.|Michigan State University Department of Neurology and Ophthalmology, East Lansing, Michigan, USA.
Andrea C
AC
Bozoki
D059787:Acute Pain / Q000175:diagnosis* / Q000453:epidemiology*; D000368:Aged; D000544:Alzheimer Disease / Q000175:diagnosis / Q000453:epidemiology*; D001342:Autonomic Nervous System Diseases / Q000175:diagnosis / Q000453:epidemiology*; D015897:Comorbidity; D003430:Cross-Sectional Studies; D059026:Diagnostic Self Evaluation; D005260:Female; D015577:Geriatric Assessment / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000453:epidemiology*; D008824:Michigan / Q000453:epidemiology; D015995:Prevalence; D012307:Risk Factors
Acute Pain; Alzheimer's Disease; Behavior; Dementia; Elderly