The Flares of Low back pain with Activity Research Study (FLAReS): study protocol for a case-crossover study nested within a cohort study.

BACKGROUND: Although it is generally accepted that physical activity and flares of low back pain (LBP) are related, evidence for the directionality of this association is mixed. The Flares of Low back pain with Activity Research Study (FLAReS) takes a novel approach to distinguish the short-term effects of specific physical activities on LBP flares from the cumulative effects of such activities, by conducting a longitudinal case-crossover study nested within a cohort study. The first aim is to estimate the short-term effects (≤ 24 h) of specific physical activities on LBP flares among Veterans in primary care in the Veterans Affairs healthcare system. The second aim is to estimate the cumulative effects of specific activities on LBP-related functional limitations at 1-year follow-up. METHODS: Up to 550 adults of working age (18-65 years) seen for LBP in primary care complete up to 36 "Scheduled" surveys over 1-year follow-up, and also complete unscheduled "Flare Window" surveys after the onset of new flares. Each survey asks about current flares and other factors associated with LBP. Surveys also inquire about activity exposures over the 24 h, and 2 h, prior to the time of survey completion (during non-flare periods) or prior to the time of flare onset (during flares). Other questions evaluate the number, intensity, duration, and/or other characteristics of activity exposures. Other exposures include factors related to mood, lifestyle, exercise, concurrent treatments, and injuries. Some participants wear actigraphy devices for weeks 1-4 of the study. The first aim will examine associations between 10 specific activity categories and participant-reported flares over 1-year follow-up. The second aim will examine associations between the frequency of exposure to 10 activity categories over weeks 1-4 of follow-up and long-term functional limitations at 12 months. All analyses will use a biopsychosocial framework accounting for potential confounders and effect modifiers. DISCUSSION: FLAReS will provide empirically derived estimates of both the short-term and cumulative effects of specific physical activities for Veterans with LBP, helping to better understand the role of physical activities in those with LBP. TRIAL REGISTRATION: ClinicalTrials.gov NCT04828330 , registered April 2, 2021.

The Moderating Effects of Cognitive Processes on Pain-related Outcomes.

Although evidence supports the importance of pain-related thoughts (ie, cognitive content, or what people think) as predictors of pain and pain-related function, evidence regarding the role of cognitive processes (ie, how people think about pain, eg, by accepting pain, not making judgments about pain, or being absorbed by the pain experience) in adjustment to chronic pain is in its early stages. Using baseline data from a clinical trial of individuals with chronic low back pain (N = 327), the study aimed to increase knowledge regarding the associations between cognitive processes, pain intensity, pain interference, and depression. The results indicate that a number of cognitive processes are significantly related to pain intensity when controlling for catastrophizing, although the pattern of associations found was opposite to those anticipated. One cognitive process (pain absorption) was found to be significantly associated with pain interference, and 9 of 10 cognitive processes were significantly associated with depression when controlling for catastrophizing. In each case, the processes thought to be adaptive were negatively associated with pain interference and depression, and processes thought to be maladaptive evidenced the opposite pattern. The findings are consistent with-but do not prove, given the cross-sectional nature of the data-the possibility that cognitive processes play an important role in adjustment to chronic pain. The potential role these variables play in depression was particularly noteworthy. Longitudinal and experimental studies to evaluate the causal nature of the associations identified are warranted. PERSPECTIVE: The study findings highlight the potential importance of cognitive process variables (ie, how people think) in adjustment to chronic pain. Research to evaluate cognitive processes as potential mechanism variables in pain treatment is warranted.