慢性疼痛を抱える成人における加重毛布の使用：パイロット研究 (EMBRACE)

Participants will receive a weighted blanket sized to approximately 10 percent of their body weight and will be instructed to use the blanket nightly during sleep. The study includes a 7-day run-in adjustment period followed by a 4-week intervention period. The run-in period allows participants to become accustomed to the blanket and assess tolerability. Participants who tolerate the blanket will continue using it nightly for the 4-week study phase. Participants will complete questionnaires at baseline, after the run-in period, and at the end of the study, along with brief weekly surveys to report adherence and experiences using the weighted blanket.

Participants will receive a weighted blanket sized to approximately 10 percent of their body weight for nightly use during sleep. Blanket weight will be assigned by body weight: 10 lb (100-149.9 lbs), 15 lb (150-199.9 lbs), 20 lb (200-249.9 lbs), and 25 lb (250-299.9 lbs). The blanket provides evenly distributed deep pressure across the body through weighted filling materials sewn into the fabric. Participants will begin with a 7-day run-in adjustment period to become accustomed to sleeping with the blanket and to assess tolerability. Those who tolerate the blanket will continue nightly use during a 4-week intervention period. The weighted blanket is intended to provide gentle pressure stimulation during sleep and is being evaluated as a non-pharmacologic approach that may support relaxation, sleep quality, and overall comfort in adults living with chronic pain.

Change in participant-reported pain intensity and interference as measured by the Pain, Enjoyment of Life, and General Activity (PEG) scale. The PEG is a validated 3-item measure assessing average pain intensity, pain interference with enjoyment of life, and pain interference with general activity over the past week, each rated on a 0-10 numeric scale. A composite score is calculated as the mean of the three items, with higher scores indicating greater pain and interference. Assessments will be administered via online surveys at baseline and at the end of the study, and scores will be compared to evaluate changes following nightly use of a weighted blanket.

Change in physical function as measured by the PROMIS-29 Physical Function subdomain. This subdomain includes four self-reported items assessing the ability to perform daily activities. Each item is rated on a 5-point scale from 5 (without any difficulty) to 1 (unable to do), with higher scores indicating better physical function. Raw scores are summed and converted to standardized T-scores (mean = 50, standard deviation = 10), with higher T-scores indicating better physical function. T-scores may be interpreted as within normal limits (>45), mild (40-44), moderate (30-39), or severe (<30) impairment. Assessments will be administered via online surveys at baseline and at the end of the study, and scores will be compared to evaluate changes in physical function following nightly use of a weighted blanket.

Change in anxiety as measured by the PROMIS-29 Anxiety subdomain. This subdomain includes four self-reported items assessing feelings of fear, difficulty focusing due to anxiety, feeling overwhelmed by worry, and general unease over the past 7 days. Each item is rated on a 5-point scale from 1 (never) to 5 (always), with higher scores indicating greater anxiety severity. Raw scores are summed and converted to standardized T-scores (mean = 50, standard deviation = 10), with higher T-scores indicating greater anxiety. T-scores may be interpreted as within normal limits (<55), mild (55-59), moderate (60-69), or severe (≥70) anxiety. Assessments will be administered via online surveys at baseline and at the end of the study, and scores will be compared to evaluate changes in anxiety following nightly use of a weighted blanket.

Change in depression as measured by the PROMIS-29 Depression subdomain. This subdomain includes four self-reported items assessing feelings of worthlessness, helplessness, depression, and hopelessness over the past 7 days. Each item is rated on a 5-point scale from 1 (never) to 5 (always), with higher scores indicating greater depressive symptoms. Raw scores are summed and converted to standardized T-scores (mean = 50, standard deviation = 10), with higher T-scores indicating greater depression severity. T-scores may be interpreted as within normal limits (<55), mild (55-59), moderate (60-69), or severe (≥70) depression. Assessments will be administered via online surveys at baseline and at the end of the study, and scores will be compared to evaluate changes in depressive symptoms following nightly use of a weighted blanket.

Change in fatigue as measured by the PROMIS-29 Fatigue subdomain. This subdomain includes four self-reported items assessing feelings of fatigue, difficulty initiating activities due to tiredness, feelings of being run-down, and average fatigue over the past 7 days. Each item is rated on a 5-point scale from 1 (not at all) to 5 (very much), with higher scores indicating greater fatigue severity. Raw scores are summed and converted to standardized T-scores (mean = 50, standard deviation = 10), with higher T-scores indicating greater fatigue. T-scores may be interpreted as within normal limits (<55), mild (55-59), moderate (60-69), or severe (≥70) fatigue. Assessments will be administered via online surveys at baseline and at the end of the study, and scores will be compared to evaluate changes in fatigue following nightly use of a weighted blanket.

Change in sleep disturbance as measured by the PROMIS-29 Sleep Disturbance subdomain. This subdomain includes four self-reported items assessing sleep quality, sleep refreshment, overall sleep problems, and difficulty falling asleep over the past 7 days. Sleep quality is rated on a 5-point scale from 1 (very good) to 5 (very poor). Sleep refreshment is rated from 1 (very much) to 5 (not at all). Sleep problems and difficulty falling asleep are rated on a 5-point scale from 1 (not at all) to 5 (very much). Raw scores are summed and converted to standardized T-scores (mean = 50, standard deviation = 10), with higher scores indicating greater sleep disturbance. T-scores may be interpreted as within normal limits (<55), mild (55-59), moderate (60-69), or severe (≥70) disturbance. Assessments will be administered via online surveys at baseline and at the end of the study, and scores will be compared to evaluate changes in sleep disturbance following nightly use of a weighted blanket.

Change in ability to participate in social roles and activities as measured by the PROMIS-29 Ability to Participate in Social Roles and Activities subdomain. This subdomain includes four self-reported items assessing difficulty participating in leisure activities, family activities, work, and activities with friends over the past 7 days. Each item is rated on a 5-point scale from 1 (always) to 5 (never), with higher scores indicating better ability to participate and less difficulty. Raw scores are summed and converted to standardized T-scores (mean = 50, standard deviation = 10), with higher T-scores indicating better functioning. T-scores may be interpreted as within normal limits (>45), mild (40-44), moderate (30-39), or severe (<30) impairment. Assessments will be administered via online surveys at baseline and at the end of the study, and scores will be compared to evaluate changes in social participation following nightly use of a weighted blanket.

Change in pain interference as measured by the PROMIS-29 Pain Interference subdomain. This subdomain includes four self-reported items assessing the extent to which pain interfered with day-to-day activities, work around the home, participation in social activities, and household chores over the past 7 days. Each item is rated on a 5-point scale from 1 (not at all) to 5 (very much), with higher scores indicating greater pain interference. Raw scores are summed and converted to standardized T-scores (mean = 50, standard deviation = 10), with higher T-scores indicating greater interference from pain. T-scores may be interpreted as within normal limits (<55), mild (55-59), moderate (60-69), or severe (≥70) pain interference. Assessments will be administered via online surveys at baseline and at the end of the study, and scores will be compared to evaluate changes in pain interference following nightly use of a weighted blanket.

Change in cognitive function as measured by the PROMIS Cognitive Function - Abilities subdomain. This subdomain includes self-reported items assessing the ability to concentrate and the ability to remember to complete tasks over the past 7 days. Each item is rated on a 5-point scale from 1 (not at all) to 5 (very much), with higher scores indicating better cognitive functioning. Raw scores are summed and converted to standardized T-scores (mean = 50, standard deviation = 10), with higher T-scores indicating better cognitive abilities. T-scores may be interpreted as within normal limits (>45), mild (40-44), moderate (30-39), or severe (<30) impairment. Assessments will be administered via online surveys at baseline and at the end of the study, and scores will be compared to evaluate changes in cognitive function following nightly use of a weighted blanket.

Change in pain intensity as measured by the PROMIS Pain Intensity subdomain. This measure includes a single self-reported item assessing average pain over the past 7 days. Pain intensity is rated on an 11-point numeric rating scale from 0 (no pain) to 10 (worst pain imaginable), with higher scores indicating greater pain intensity. Scores may be reported as raw values or converted to standardized T-scores (mean = 50, standard deviation = 10), with higher T-scores indicating greater pain severity. Assessments will be administered via online surveys at baseline and at the end of the study, and scores will be compared to evaluate changes in pain intensity following nightly use of a weighted blanket.

Participants will complete brief weekly surveys reporting how consistently they used the weighted blanket during sleep. Responses will be used to assess adherence to the nightly intervention.

Participants will complete open-ended survey questions describing their experiences using the weighted blanket, including perceived benefits, challenges, and overall acceptability of the intervention.