Age Differences in Pain Responses

Abstract

One in five Canadians report experiencing chronic pain, which is associated with numerous negative psychological and physical consequences (Schopflocher et al., 2011). Older adults are more likely to experience pain than younger people and the degree of pain-related interference increases with age (Thomas et al., 2004). This is concerning given that pain is routinely underassessed and undertreated in older persons (American Pain Foundation, 2008; Kaye et al., 2010; Lautenbacher, 2014; Malec & Shega, 2015). Researchers have found many age-related differences in pain responses, such as pain perception and reporting and attitudes toward pain (Gibson & Farrell, 2004; Gibson & Helme, 2001; Lautenbacher et al., 2017; Tumi et al., 2017; Yong et al., 2001). Coping is thought to play an important role in the pain experience (Chan et al., 2012; Keefe & Williams, 1990; LaChapelle & Hadjistavropoulos, 2005; Sorkin et al., 1990; Watkins et al., 1999). Despite researchers having examined the influence of coping on pain, there is a lack of research comparing younger and older adults’ coping with pain, while measuring multiple facets of the pain experience (e.g., pain threshold/tolerance, non-verbal facial expressions of pain, and self-reported pain intensity/unpleasantness), during a controlled experimental pain-task. The goal of this investigation was to examine age differences in a variety of pain responses in real time by comparing older and younger adults’ verbal and nonverbal pain responses during a thermal pain task. Real-time coping strategies were measured through the use of a ‘think aloud’ protocol that was analyzed and coded based on empirically-supported coping categories. It was hypothesized that there would be age differences in pain responses (i.e., pain threshold, pain tolerance), coping, and pain attitudes. Non-verbal pain/emotional expressions were not expected to differ as a function of age (Hadjistavropoulos et al., 2002; Hadjistavropoulos et al., 2000; Kunz et al., 2008; Prkachin, 2009; Sheu et al., 2011). Drawing from the communications model of pain (Craig, 2009; Hadjistavropoulos & Craig, 2002; Hadjistavropoulos et al., 2004; Hadjistavropoulos et al., 2011; Prkachin & Craig, 1995), and in line with previous research suggesting that specific coping strategies play an important role in pain outcomes (Harland & Georgieff, 2003; McCormick et al., 2015; Monticone et al., 2014; Robinson et al., 1997), it was expected that coping would mediate the relationship between age and pain outcomes. As expected, there were age differences in coping, with younger adults using more Coping Self-Statements, Ignoring Sensation, and Other real-time coping strategies than older adults. In a retrospective measure of coping (i.e., the CSQ-R), younger adults endorsed more Coping Self-Statements and older adults indicated using more Praying. Also as expected, use of “CSQ-R Adaptive Coping” strategies was related to lower pain ratings, whereas use of “CSQ-R Maladaptive Coping” strategies was related to higher pain ratings. Results from mediation analyses revealed that older adults made less use of “CSQ-R Adaptive Coping” strategies than younger adults, which was related to older adults having higher self-reported pain ratings than younger adults. No age differences were found in pain threshold/tolerance or pain attitudes (i.e., stoicism and cautiousness). Although there were age-differences in the specificity of facial responses—e.g., specific action units related to pain—there were no age-differences in global facial expressions of pain intensity. Results from this investigation add specificity to the communications model of pain. Furthermore, findings may contribute to the advancement of pain treatment protocols and age-specific guidelines for the management of pain.