R4. Association of Sleep Disturbance and Pain in Chronic Low Back Pain: Subjective and Objective Sleep Indicators

Sleep disturbance in chronic low back pain (CLBP) is a common problem, which may intensify pain. Few studies have examined subjective (self-assessment) and objective (wrist actigraphy) measures of sleep simultaneously. This study aimed to evaluate the association between pain experience in CLBP and sleep disturbance, using subjective and objective sleep indicators. CLBP (N=69; mean age 56±12 yrs;57% female) patients were enrolled and self-report measures of sleep indicators (quality, disturbance) Pittsburgh Sleep Quality Index (PSQI), sleep diary (SD) and pain experiences (severity and interference with activities) using Brief Pain Inventory (BPI) obtained. All participants completed PSQI and SD for average of six nights. A subset of the sample (N=13; mean age 55±9 yrs.; 92% female) tracked their sleep for six nights using a wrist actigraphy (WA). Eighty five percent of the total sample had mean PSQI scores at or above the cut-score indicating poor sleep. Individuals who reported greater PSQI sleep disturbance also recorded greater sleep awakening (r=.4, p=.002) and feeling less rested upon awakening (r=-.35, p=.013) in their sleep diaries. Greater pain severity was associated with greater sleep disturbance (r=.59, p=.000) and with poorer sleep quality (r=-.26, p= 0.06) and feeling less rested (r=-.29, p= 0.03). Likewise, greater pain interference was associated with greater sleep disturbance (r=.45, p=.000) and with poor sleep quality (r=-.32, p= 0.019) and feeling less rested (r=-.32, p= 0.019). Sub-group analysis of wrist actigraphy data were consistent with poor sleep quality which revealed increased sleep latency (28.12+13.1 min), lower sleep efficiency (80.86+6.8%), and increased awakenings after sleep onset (49.11±23.9), relative to normative values. Findings demonstrate that CLBP patients who reported greater sleep disturbance experienced greater pain severity and greater pain interference with activities. Actigraphy data adds insight to understand sleep disturbances. Including assessment and management of sleep disturbance will provide for more comprehensive management in CLBP.