Examining the Role of Central Sensitization with Aging: an Investigation of Older Adults with and without Chronic Low Back Pain - PROJECT SUMMARY/ABSTRACT Chronic pain affects over 5 million older adults every year in the United States. This burden is expected to worsen in the coming years given that the general population is aging, chronic pain prevalence is inordinately high among older adults, and it is unknown why aging is a risk factor for chronic pain disorders. The National Institute on Aging is keenly aware of this impasse, as evidenced by requests for research to focus on the “elucidation of mechanisms underlying pain experience and its consequences in aging”. Literature has established sensitization of the central nervous system (termed central sensitization) as an impairment that amplifies pain perception in young and middle aged adults with chronic pain, leading to pain persistence and resultant disability. However, a paucity of research has evaluated the presence and consequences of central sensitization in geriatric chronic pain conditions, including chronic low back pain. This gap in knowledge is further complicated by a lack of understanding whether central sensitization occurs with aging, and an absence of definitive diagnostic criteria for central sensitization. Therefore, the goals of this proposal are to elucidate if and how central sensitization develops as a result of biological aging, and characterize the presence and clinical implications of central sensitization in older adults with chronic low back pain. In Aim 1, we will determine the extent to which older adults with chronic low back pain demonstrate increased static and dynamic pain sensitivity compared to older and younger adults without chronic pain. For Aim 2, we will quantify differences in experimentally-induced sensitization between these three groups. In Aim 3, we will examine the relationship between indicators of central sensitization and clinical measures of pain, physical function and perceived disability among older adults with chronic low back pain. The central hypothesis of this proposal is that older adults with chronic low back pain will demonstrate the greatest magnitude of central sensitization, which will be associated with greater clinical pain intensity, poorer physical function, and worse perceived disability. The results have the potential to inform primary, secondary and tertiary prevention efforts by determining if CS occurs with biological aging, optimizing the identification of CS by combining standard and novel measurement methodologies, and providing foundational evidence for a potentially modifiable mechanism that burdens older adults with chronic low back pain, respectively. This proposal is a critical first step towards the long-term goal of this fellowship applicant, which is to improve primary, secondary and tertiary prevention efforts for vulnerable chronic pain populations by quantifying and intervening upon mechanisms (such as CS) that underlie maladaptive pain sensitivity. Additionally, this fellowship proposal will provide the applicant with structured training from mentors with expertise in gerontology, pain science and rehabilitation; this training will not only facilitate completion of this research project, but also prepare the applicant for a career as a productive clinician scientist.
