Pain Experience in Dementia Subtypes: A Systematic Review.

Recently, the number of studies focusing on pain in dementia has increased considerably. Still, little attention has been paid to the influence of the neuropathology of different dementia subtypes on pain experience. In 2003, a review identified several studies that indicated a relation between dementia subtype and pain experience. Now, ten years later, an update is warranted. We conducted a systematic review to identify studies that assessed pain experience and dementia subtypes by searching PubMed, Embase, PsycINFO, CINAHL, and Cochrane Library. Inclusion criteria were: (1) major dementia subtype diagnosis i.e. Alzheimer's dementia (AD), vascular dementia (VaD), frontotemporal dementia (FTD), dementia with Lewy Bodies (DLB); (2) age ≥60 years; and (3) pain experience. We identified twelve studies that addressed AD, three studies VaD, one study FTD, and no studies DLB. In AD, studies on clinical pain indicate a reduced pain experience compared to controls, whereas experimental studies show inconsistent findings. In VaD, clinical studies found that primary caregivers rated pain equal to cognitively intact controls, although more painful locations were reported. During self-report, elderly with VaD reported higher pain levels than cognitively intact controls. In FTD, a significantly lower pain sensitivity to experimental pain was found. Considering the limited number of studies, these findings should be considered with caution. Existing literature provides some evidence that dementia subtype affects pain experience. Further research is needed to clarify the relation between dementia subtype and pain experience as it could serve as basis for improving the assessment and management of pain in people with dementia.