Dementia is one of the most frequent causes of cognitive impair- ment in older adults, with a forecast worldwide increase in inci- dence from 25 million in 2000 to 114 million by 2050.4Dementia involves the development of multiple cognitive deficits manifested by impaired memory and involving cognitive disturbances and the loss of language, the ability to recognize or identify objects, and executive function.5 As dementia progresses to advanced stages, individuals become increasingly dependent in all activities of daily living, often requiring skilled nursing care.
The burden of dementia in the older adult population is com- pounded by a considerable pain burden.6In institutionalized older adults with dementia, pain or potentially painful conditions are common, with prevalence estimates ranging between 49% and 83%.7,8One large-scale nursing home study documented that half of the residents reported having pain in the past week and a fourth experienced pain daily.9Moreover, a similar prevalence of pain was documented in subgroups of cognitively intact and impaired residents. The most common pain-associated conditions in the cognitively impaired residents were arthritis, previous hip fracture, osteoporosis, pressure ulcers, depression, and a history of a recent fall, unsteady gait, and verbally abusive behavior.9
The severity of cognitive impairment and the progression of language deficit vary by type and stage of disease, environmental factors, and individual characteristics. In Alzheimer’s disease (AD), which accounts for over half of dementia cases, memory deficit is the presenting symptom, with language impairments developing gradually over the course of the illness.10 Typically, AD patients are fluent until the middle to late stages of the disease, whereas global language disturbance and mutism are generally present in the end stage of AD. With vascular dementia, the second most prevalent type, the trajectory of language impairment resembles that observed in AD.11By comparison, individuals with frontotem- poral dementia (behavioral type) and primary progressive aphasia show earlier onset of language impairment and more rapid decline.10 The subtype of dementia also appears to affect pain 24 Chapter 5 ASSESSMENT OF PAIN IN THE NONVERBAL AND/OR COGNITIVELY IMPAIRED OLDER ADULT
98. McCracken LM, Zayfert C, Gross RT. The Pain Anxiety Symptoms Scale: development and validation of a scale to measure fear of pain. Pain 1992;50:6773.
99. Kori S, Miller R, Todd D. Kinesiophobia: a new view of chronic pain behavior. Pain Manage 1990;3:3543.
100. Cook AJ, Brawer PA, Vowles KE. The fear-avoidance model of chronic pain: validation and age analysis using structural equation modeling. Pain 2006;121:195206.
101. Burwinkle T, Robinson JP, Turk DC. Fear of movement: factor structure of the Tampa scale of kinesiophobia in patients with fibromyalgia syndrome. J Pain 2005;6:384391.
102. Lachman ME, Howland J, Tennstedt S, et al. Fear of falling and activity restriction: the survey of activities and fear of falling in the elderly (SAFE). J Gerontol B Psychol Sci Soc Sci 1998;53:4350.
103. Rosenstiel AK, Keefe FJ. The use of coping strategies in chronic low back pain patients: relationship to patient characteristics and current adjustment. Pain 1983;17:3344.
104. Jensen MP, Turner JA, Romano JM, Strom SE. The Chronic Pain Coping Inventory: development and preliminary validation. Pain 1995;60:203216.
105. Felton BJ, Revenson TA. Coping with chronic illness: a study of illness controllability and the influence of coping strategies on psychological adjustment. J Consult Clin Psychol 1984;52:343353. 106. Felton BJ, Revenson TA, Hinrichsen GA. Stress and coping in the
explanation of psychological adjustment among chronically ill adults. Soc Sci Med 1984;18:889898.
107. Folkman S, Lazarus RS. If it changes it must be a process: study of emotion and coping during three stages of a college examination. J Pers Soc Psychol 1985;48:150170.
Chapter 5
ASSESSMENT OF
PAIN IN THE
NONVERBAL AND/OR
COGNITIVELY
IMPAIRED
OLDER
ADULT
Karen Bjoro and Keela Herr
INTRODUCTION
Pain is a highly subjective and personal experience. Self-report is widely accepted as the most reliable source of information on an individual’s pain experience and is considered to be the ‘‘gold stan- dard’’ in most populations.1,2Yet, older adults with severe cognitive impairment or who are unconscious and/or intubated during an episode of severe critical illness are unable to communicate their pain experience. The inability to use verbal language represents a major barrier to pain assessment and treatment. For these indivi- duals, alternative approaches to pain assessment, involving obser- vation of pain behaviors and proxy pain reports, are necessary.
The ability to use language is a comprehensive and complex behavior acquired in early childhood. The primary faculties of lan- guage include speaking, signing, and language comprehension, whereas reading and writing are secondary abilities.3With language impairment (e.g., aphasia, dysphasia), the ability to communicate orally, through signs, or in writing or the ability to understand such communications may be severely compromised. Language impairment (e.g., aphasia, dysphasia) is associated with many med- ical illnesses and clinical states (Box 51). The loss of ability to com- municate is a core feature of many types of cognitive impairment (e.g., dementia, delirium) and occurs frequently with severe critical illness as well as at the end of life, with the naturally occurring dete- rioration in cognition resulting from ensuing death and/or sedation. The purpose of this chapter is to review the current basis for pain assessment in three nonverbal populations: those with advanced dementia, those with delirium, and those experiencing
an episode of critical illness who are unable to communicate owing to an unconscious state or the presence of an endotracheal tube. General principles of pain assessment and specific recommen- dations for pain assessment of nonverbal older adults are discussed. Finally, a selection of behavioral pain assessment tools for use with these nonverbal older adults is critiqued.
CHALLENGE OF DEMENTIA FOR PAIN
ASSESSMENT
Dementia is one of the most frequent causes of cognitive impair- ment in older adults, with a forecast worldwide increase in inci- dence from 25 million in 2000 to 114 million by 2050.4Dementia involves the development of multiple cognitive deficits manifested by impaired memory and involving cognitive disturbances and the loss of language, the ability to recognize or identify objects, and executive function.5 As dementia progresses to advanced stages, individuals become increasingly dependent in all activities of daily living, often requiring skilled nursing care.
The burden of dementia in the older adult population is com- pounded by a considerable pain burden.6In institutionalized older adults with dementia, pain or potentially painful conditions are common, with prevalence estimates ranging between 49% and 83%.7,8One large-scale nursing home study documented that half of the residents reported having pain in the past week and a fourth experienced pain daily.9Moreover, a similar prevalence of pain was documented in subgroups of cognitively intact and impaired residents. The most common pain-associated conditions in the cognitively impaired residents were arthritis, previous hip fracture, osteoporosis, pressure ulcers, depression, and a history of a recent fall, unsteady gait, and verbally abusive behavior.9
The severity of cognitive impairment and the progression of language deficit vary by type and stage of disease, environmental factors, and individual characteristics. In Alzheimer’s disease (AD), which accounts for over half of dementia cases, memory deficit is the presenting symptom, with language impairments developing gradually over the course of the illness.10 Typically, AD patients are fluent until the middle to late stages of the disease, whereas global language disturbance and mutism are generally present in the end stage of AD. With vascular dementia, the second most prevalent type, the trajectory of language impairment resembles that observed in AD.11By comparison, individuals with frontotem- poral dementia (behavioral type) and primary progressive aphasia show earlier onset of language impairment and more rapid decline.10 The subtype of dementia also appears to affect pain 24 Chapter 5 ASSESSMENT OF PAIN IN THE NONVERBAL AND/OR COGNITIVELY IMPAIRED OLDER ADULT
response. In frontotemporal dementia, a decrease in affective pain response has been documented that could be explained by atrophy of the prefrontal cortex. In contrast, with vascular dementia, an increase in affective response is reported that may be related to white matter lesions and deafferentiation in these patients.12
Neuropathologic processes in dementia seriously affect the ability of those with advanced stages of disease to communicate pain. However, only a few studies have investigated the relationship between dementia and the neuropathology of pain, and these are lim- ited to experimental pain studies in individuals with AD. Whereas sensory discriminatory aspects of pain are processed in the lateral pain system (e.g., lateral thalamus), motivational affective aspects are processed in the medial pain system (e.g., anterior cingulate gyrus, hippocampus).13,14 Noxious stimuli transmitted via the lateral pain system are interpreted in the somatosensory cortex, involving areas of the brain that are relatively unaffected by AD neuropathology. This explains the finding that sensory aspects of pain remain intact in individuals with AD. Nevertheless, the lateral pain system does show some functional decline, as evidenced by an elevated pain threshold and reports of less intense pain in those with AD. By contrast, the medial pain system is severely affected by pathologic processes in AD.12,15The affective pain response (e.g., pain tolerance) was significantly increased in individuals with AD compared with those without dementia.12Thus, empirical studies indicate that older adults with dementia are not less sensitive to pain but they may fail to interpret sensations as painful.
Despite these findings, evidence suggests that older adults with advanced dementia underreport pain compared with those who are cognitively intact. Research studies have documented a decrease in the number of pain complaints with increasing severity of cognitive impairment in older adults with dementia.16,17Inability to commu- nicate is a major barrier to adequate pain assessment and treatment in older adults with advanced dementia. Cognitively impaired older adults hospitalized with a hip fracture received significantly less opioid analgesia than those with less or no impairment.18,19 In the nursing home setting, pain is documented less frequently in residents unable to communicate their pain, even though they have a similar number of painful diagnoses.9,20,21 Moreover, less analgesia is prescribed and administered for cognitively impaired nursing home residents, even when the impaired residents have numbers of painful diagnoses similar to those in cognitively intact residents.22,23Thus, the inability to communicate in older adults with dementia is a major barrier to both assessment and treatment. Language impairment is also common in delirium.