A Cross-Sectional Study of Pain Sensitivity and Unpleasantness in People with Vascular Dementia

Objective Advanced age is associated with a higher risk of both pain and dementia, with many studies finding that dementia often heightens sensitivity to pain. Vascular dementia (VaD) is the second most common type of dementia. Only a few observational or retrospective studies have examined pain responsiveness in VaD, suggesting that it could increase pain unpleasantness (i.e., pain affect). This study compared thermal pain psychophysics between a cohort of patients with VaD and healthy control (HC) subjects. Design Single-center, cross-sectional, between-subjects design. Subjects Verbally communicative patients with probable VaD (n = 23) and age- and sex-matched HCs (n = 23). Methods A thermal psychophysics protocol assessed “mild pain” and “moderate pain” thresholds (temperature in degrees Celsius) and associated unpleasantness ratings (0–20 scale) in both the VaD and HC groups. Psychophysics were compared between groups by way of a mixed-effects analysis, controlling for depressive symptoms. Results There were no significant differences between groups for pain thresholds (main effect P = 0.086, Cohen’s d: mild = 0.55, moderate = 0.27). However, unpleasantness ratings were higher in the VaD group than in the HC group (main effect P = 0.003; mild pain P = 0.022, Cohen’s d = 0.79; moderate pain P = 0.057, Cohen’s d = 0.6). Conclusions These results are consistent with prior observational findings suggesting that VaD could make patients more susceptible to pain, particularly its affective component.