Discrepancy between stimulus response and tolerance of pain in Alzheimer disease

TY - JOUR

T1 - Discrepancy between stimulus response and tolerance of pain in Alzheimer disease

AU - Jensen-Dahm, Christina

AU - Werner, Mads U

AU - Jensen, Troels Staehelin

AU - Ballegaard, Martin

AU - Andersen, Birgitte Bo

AU - Høgh, Peter

AU - Waldemar, Gunhild

N1 - © 2015 American Academy of Neurology.

PY - 2015/4/14

Y1 - 2015/4/14

N2 - Background: Affective-motivational and sensory-discriminative aspects of pain were investigated in patients with mild to moderate Alzheimer disease (AD) and healthy elderly controls using the cold pressor test tolerance and repetitive stimuli of warmth and heat stimuli, evaluating the stimulus-response function. Methods: A case-control design was applied examining 33 patients with mild to moderate AD dementia and 32 healthy controls with the cold pressor test (4°C). Warmth detection threshold (WDT) and heat pain threshold (HPT) were assessed using 5 stimulations. A stimulus-response function was estimated using 4 incrementally increasing suprathreshold heat stimuli. Results: Cold pressor tolerance was lower in patients with AD dementia than in controls (p 0.027). There were no significant differences between groups regarding WDT and HPT. Significant successive increases in HPT assessments indicated habituation (p < 0.0001), which was similar in the 2 groups (p 0.85). A mixed model for repeated measures demonstrated that pain rating of suprathreshold stimuli depended on HPT (p 0.0004) and stimulus intensity (p < 0.0001). Patients with AD dementia had significantly lower increases in pain ratings than controls during suprathreshold stimulation (p 0.0072). Conclusion: Our results indicate that AD dementia is not associated with a propensity toward development of sensitization or a lack of habituation, suggesting preservation of sensory-discriminative aspects of pain perception. The results further suggest that the attenuated cold pressor pain tolerance may relate to impairment of coping abilities. Paradoxically, we found an attenuated stimulus-response function, compared to controls, suggesting that AD dementia interferes with pain ratings over time, most likely due to memory impairment.

AB - Background: Affective-motivational and sensory-discriminative aspects of pain were investigated in patients with mild to moderate Alzheimer disease (AD) and healthy elderly controls using the cold pressor test tolerance and repetitive stimuli of warmth and heat stimuli, evaluating the stimulus-response function. Methods: A case-control design was applied examining 33 patients with mild to moderate AD dementia and 32 healthy controls with the cold pressor test (4°C). Warmth detection threshold (WDT) and heat pain threshold (HPT) were assessed using 5 stimulations. A stimulus-response function was estimated using 4 incrementally increasing suprathreshold heat stimuli. Results: Cold pressor tolerance was lower in patients with AD dementia than in controls (p 0.027). There were no significant differences between groups regarding WDT and HPT. Significant successive increases in HPT assessments indicated habituation (p < 0.0001), which was similar in the 2 groups (p 0.85). A mixed model for repeated measures demonstrated that pain rating of suprathreshold stimuli depended on HPT (p 0.0004) and stimulus intensity (p < 0.0001). Patients with AD dementia had significantly lower increases in pain ratings than controls during suprathreshold stimulation (p 0.0072). Conclusion: Our results indicate that AD dementia is not associated with a propensity toward development of sensitization or a lack of habituation, suggesting preservation of sensory-discriminative aspects of pain perception. The results further suggest that the attenuated cold pressor pain tolerance may relate to impairment of coping abilities. Paradoxically, we found an attenuated stimulus-response function, compared to controls, suggesting that AD dementia interferes with pain ratings over time, most likely due to memory impairment.

KW - Aged

KW - Alzheimer Disease

KW - Case-Control Studies

KW - Female

KW - Habituation, Psychophysiologic

KW - Humans

KW - Male

KW - Pain Measurement

KW - Pain Perception

KW - Pain Threshold

U2 - 10.1212/WNL.0000000000001465

DO - 10.1212/WNL.0000000000001465

M3 - Journal article

C2 - 25788560

SN - 0028-3878

VL - 84

SP - 1575

EP - 1581

JO - Neurology

JF - Neurology

IS - 15

ER -