Clinically significant changes in pain along the Pain Intensity Numerical Rating Scale in patients with chronic low back pain

Hidenori Suzuki, Shuichi Aono, Shinsuke Inoue, Yasuaki Imajo, Norihiro Nishida, Masahiro Funaba, Hidenori Harada, Aki Mori, Mishiya Matsumoto, Fumihiro Higuchi, Shin Nakagawa, Shu Tahara, Satoshi Ikeda, Hironori Izumi, Toshihiko Taguchi, Takahiro Ushida, Takashi Sakai, Hidenori Suzuki, Shuichi Aono, Shinsuke Inoue, Yasuaki Imajo, Norihiro Nishida, Masahiro Funaba, Hidenori Harada, Aki Mori, Mishiya Matsumoto, Fumihiro Higuchi, Shin Nakagawa, Shu Tahara, Satoshi Ikeda, Hironori Izumi, Toshihiko Taguchi, Takahiro Ushida, Takashi Sakai

Abstract

Low back pain (LBP) is the most common cause of chronic pain. Numerous clinical scales are available for evaluating pain, but their objective criteria in the management of LBP patients remain unclear. This study aimed to determine an objective cutoff value for a change in the Pain Intensity Numerical Rating Scale (ΔPI-NRS) three months after LBP treatment. Its utility was compared with changes in six commonly used clinical scales in LBP patients: Pain Disability Assessment Scale (PDAS), Pain Self-Efficacy Questionnaire (PSEC), Pain Catastrophizing Scale (PCS), Athens Insomnia Scale (AIS), EuroQoL 5 Dimension (EQ5D), and Locomo 25. We included 161 LBP patients treated in two representative pain management centers. Patients were partitioned into two groups based on patient's global impression of change (PGIC) three months after treatment: satisfied (PGIC = 1, 2) and unsatisfied (3-7). Multivariate logistic regression analysis was performed to explore relevant scales in distinguishing the two groups. We found ΔPI-NRS to be most closely associated with PGIC status regardless of pre-treatment pain intensity, followed by ΔEQ5D, ΔPDAS, ΔPSEC, and ΔPCS. The ΔPI-NRS cutoff value for distinguishing the PGIC status was determined by ROC analysis to be 1.3-1.8 depending on pre-treatment PI-NRS, which was rounded up to ΔPI-NRS = 2 for general use. Spearman's correlation coefficient revealed close relationships between ΔPI-NRS and the six other clinical scales. Therefore, we determined cutoff values of these scales in distinguishing the status of ΔPI-NRS≥2 vs. ΔPI-NRS<2 to be as follows: ΔPDAS, 6.71; ΔPSEC, 6.48; ΔPCS, 6.48; ΔAIS, 1.91; ΔEQ5D, 0.08; and ΔLocomo 25, 9.31. These can be used as definitive indicator of therapeutic outcome in the management of chronic LBP patients.

Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Fig 1. Study flowchart of the study…
Fig 1. Study flowchart of the study to show how to lead the MCID and the cutoff values.
CLBP; Chronic low back pain, PI-NRS; Pain Intensity Numerical Rating Scale, PDAS; Pain Disability Assessment Scale, HADS; The Hospital Anxiety and Depression Scale, PCS; Pain Catastrophizing Scale, EQ5D; EuroQoL 5 Dimension, PSEC; Pain Self-Efficacy Questionnaire, AIS; Athens Insomnia Scale.
Fig 2. Receiver operating characteristic (ROC) analysis…
Fig 2. Receiver operating characteristic (ROC) analysis of 8 major clinical scales for their utility in distinguishing the status of satisfaction based on the patient’s global impression of change (PGIC).
Post-treatment changes in the 8 major clinical scales were compared between two groups, those with and without satisfaction by PGIC. The degrees of separation of the two groups were evaluated by ROC analyses. The area under the curve is shown next to the name of each clinical scale.
Fig 3. Minimal clinically important difference (MCID)…
Fig 3. Minimal clinically important difference (MCID) and cutoff values for Δ Pain Intensity Numerical Rating Scale (PI-NRS) according to the baseline severity of PI-NRS.
ΔPI-NRS was partitioned into two groups by the level of patient’s global impression of change (1–2 vs. 3–7). Optimal cutoff level was estimated as the ΔPI-NRS value at which sensitivity and specificity were equal. This analysis was done in three ways by subgrouping patients according to pre-treatment severity of PI-NRS: moderate, severe, and moderate + severe.
Fig 4. Associations of Δ Pain Intensity…
Fig 4. Associations of Δ Pain Intensity Numerical Rating Scale (PI-NRS) with post-treatment changes in 6 clinical scales.
Distributions of post-treatment changes in the 6 clinical scales were compared between two groups partitioned at the cutoff value of ΔPI-NRS = 2.0. The degree of separation of the two groups is expressed as an area under curve (AUC) by the receiver operating characteristic analysis and shown on top of each graph, together with the optimal cutoff value for the distinction. The table on the right shows a list of the AUCs and standard error of the AUCs that were determined for all clinical parameters by use of the same analysis described above.

References

    1. Chou R, Shekelle P. Will this patient develop persistent disabling low back pain? JAMA 2010;303:1295–302. 10.1001/jama.2010.344
    1. WHO. The burden of musculoskeletal conditions at the start of the new millennium. World Health Organ Tech Rep Ser. 2003;919:1–218.
    1. Chauny JM, Paquet J, Lavigne G, Marquis M, Daoust R. Evaluating acute pain intensity relief: challenges when using an 11-point numerical rating scale. PAIN 2016;157:355–60. 10.1097/j.pain.0000000000000382
    1. Farrar JT, Young JP Jr, LaMoreaux L, Werth JL, Poole RM. Clinical importance of changes in chronic pain intensity measured on an 11-point numerical pain rating scale. PAIN 2001;94:149–58. 10.1016/s0304-3959(01)00349-9
    1. Parker SL, Mendenhall SK, Shau DN, Adogwa O, Anderson WN, Devin CJ, et al. Minimum clinically important difference in pain, disability, and quality of life after neural decompression and fusion for same-level recurrent lumbar stenosis: understanding clinical versus statistical significance. J Neurosurg Spine 2012;16:471–8. 10.3171/2012.1.SPINE11842
    1. Balestroni G, Bertolotti G. EuroQol-5D (EQ-5D): an instrument for measuring quality of life. Monaldi Arch Chest Dis 2012;78:155–9. 10.4081/monaldi.2012.121
    1. Dolan P. Modeling valuations for EuroQol health states. Med Care 1997;35:1095–108. 10.1097/00005650-199711000-00002
    1. Kim HJ, Kwon OH, Chang BS, Lee CK, Chun HJ, Yeom JS. Change in pain catastrophizing in patients with lumbar spinal surgery. Spine J 2018;18:115–121. 10.1016/j.spinee.2017.06.028
    1. Chiarotto A, Boers M, Deyo RA, Buchbinder R, Corbin TP, Costa LOP, et al. Core outcome measurement instruments for clinical trials in nonspecific low back pain. PAIN 2018;159:481–95. 10.1097/j.pain.0000000000001117
    1. Nakamura K, Ogata T. Locomotive syndrome: definition and management. Clin Rev Bone Miner Metab 2016;14:56–67. 10.1007/s12018-016-9208-2
    1. Nicholas MK. The pain self-efficacy questionnaire: Taking pain into account. Eur J Pain 2007;11:153–63. 10.1016/j.ejpain.2005.12.008
    1. Nicholas MK, Asghari A, Blyth FM. What do the numbers mean? Normative data in chronic pain measures. PAIN 2008;134:158–73. 10.1016/j.pain.2007.04.007
    1. Soldatos CR, Dikeos DG, Paparrigopoulos TJ. Athens Insomnia Scale: validation of an instrument based on ICD-10 criteria. J Psychosom Res 2000;48:555–60. 10.1016/s0022-3999(00)00095-7
    1. Sullivan MJ, Thorn B, Haythornthwaite JA, Keefe F, Martin M, Bradley LA, et al. Theoretical perspectives on the relation between catastrophizing and pain. Clin J Pain 2001;17:52–64. 10.1097/00002508-200103000-00008
    1. Yamashiro K, Arimura T, Iwaki R, Jensen MP, Kubo C, Hosoi M. A multidimensional measure of pain interference: Reliability and validity of the pain disability assessment scale. Clin J Pain 2011;27:338–43. 10.1097/AJP.0b013e318204858a
    1. Strong J, Unruh AM, Wright A, Baxter GD. Pain: A textbook for therapists. London: Churchill Livingstone; 2001. pp. 480.
    1. Boonstra AM, Schiphorst Preuper HR, Balk GA, Stewart RE. Cut-off points for mild, moderate, and severe pain on the visual analogue scale for pain in patients with chronic musculoskeletal pain. PAIN 2014;155:2545–50. 10.1016/j.pain.2014.09.014
    1. Emshoff R, Bertram S, Emshoff I. Clinically important difference thresholds of the visual analog scale: A conceptual model for identifying meaningful intraindividual changes for pain intensity. PAIN 2011;152:2277–82. 10.1016/j.pain.2011.06.003
    1. ten Klooster PM, Drossaers-Bakker KW, Taal E, van de Laar MA. Patient-perceived satisfactory improvement (PPSI): interpreting meaningful change in pain from the patient's perspective. PAIN 2006;121:151–7. 10.1016/j.pain.2005.12.021
    1. van der Roer N, Ostelo RW, Bekkering GE, van Tulder MW, de Vet HC. Minimal clinically important change for pain intensity, functional status and general health status in patients with nonspecific low back pain. Spine (Phila Pa 1976) 2006;31:578–82.
    1. Hayashi K, Arai YC, Ikemoto T, Nishihara M, Suzuki S, Hirakawa T, et al. Predictive factors for the outcome of multidisciplinary treatments in chronic low back pain at the first multidisciplinary pain center of Japan. J Phys Ther Sci 2015;27:2901–5. 10.1589/jpts.27.2901
    1. Keller S, Bann CM, Dodd SL, Schein J, Mendoza TR, Cleeland CS. Validity of the brief pain inventory for use in documenting the outcomes of patients with noncancer pain. Clin J Pain 2004;20:309–18. 10.1097/00002508-200409000-00005
    1. Jaeschke R, Singer J, Guyatt GH. Measurement of health status. Ascertaining the minimal clinically important difference. Control Clin Trials 1989;10:407–15. 10.1016/0197-2456(89)90005-6
    1. MacDowall A, Skeppholm M, Robinson Y, Olerud C. Validation of the visual analog scale in the cervical spine. J Neurosurg Spine 2018;28:227–35. 10.3171/2017.5.SPINE1732
    1. Parker SL, Mendenhall SK, Shau D, Adogwa O, Cheng JS, Anderson WN, et al. Determination of minimum clinically important difference in pain, disability, and quality of life after extension of fusion for adjacent-segment disease. J Neurosurg Spine 2012;16:61–7. 10.3171/2011.8.SPINE1194
    1. Cohen J. A power primer. Psychol Bull 1992;112:155–9. 10.1037//0033-2909.112.1.155
    1. Copay AG, Subach BR, Glassman SD, Polly DW Jr, Schuler TC. Understanding the minimum clinically important difference: a review of concepts and methods. Spine J 2007;7:541–6. 10.1016/j.spinee.2007.01.008
    1. Crosby RD, Kolotkin RL, Williams GR. Defining clinically meaningful change in health-related quality of life. J Clin Epidemiol 2003;56:395–407. 10.1016/s0895-4356(03)00044-1
    1. Lee JS, Hobden E, Stiell IG, Wells GA. Clinically important change in the visual analog scale after adequate pain control. Acad Emerg Med 2003;10:1128–30. 10.1111/j.1553-2712.2003.tb00586.x
    1. Nicholas MK, Asghari A, Blyth FM, Wood BM, Murray R, McCabe R, et al. Long-term outcomes from training in self-management of chronic pain in an elderly population: a randomized controlled trial. PAIN 2017;158:86–95. 10.1097/j.pain.0000000000000729
    1. Liu S, Schwab F, Smith JS, Klineberg E, Ames CP, Mundis G, et al. Likelihood of reaching minimal clinically important difference in adult spinal deformity: a comparison of operative and nonoperative treatment. Ochsner J 2014;14:67–77.
    1. Iizuka Y, Iizuka H, Mieda T, Tsunoda D, Sasaki T, Tajika T, et al. Prevalence of chronic nonspecific low back pain and its associated factors among middle-aged and elderly people: an analysis based on data from a musculoskeletal examination in Japan. Asian Spine J 2017;11:989–97. 10.4184/asj.2017.11.6.989
    1. Stratford PW, Binkley JM, Riddle DL, Guyatt GH. Sensitivity to change of the Roland-Morris Back Pain Questionnaire: part 1. Phys Ther 1998;78:1186–96. 10.1093/ptj/78.11.1186
    1. Beaton DE, Boers M, Wells GA. Many faces of the minimal clinically important difference (MCID): a literature review and directions for future research. Curr Opin Rheumatol 2002;14:109–14. 10.1097/00002281-200203000-00006
    1. Bombardier C, Hayden J, Beaton DE. Minimal clinically important difference: low back pain. Outcome measures. J Rheumatol 2001;28:431–8.
    1. Copay AG, Glassman SD, Subach BR, Berven S, Schuler TC, Carreon LY. Minimum clinically important difference in lumbar spine surgery patients: a choice of methods using the Oswestry Disability Index, Medical Outcomes Study questionnaire Short Form 36, and pain scales. Spine J 2008;8:968–74. 10.1016/j.spinee.2007.11.006
    1. Tetreault L, Nouri A, Kopjar B, Côté P, Fehlings MG. The minimum clinically important difference of the Modified Japanese Orthopaedic Association Scale in patients with degenerative cervical myelopathy. Spine (Phila Pa 1976) 2015;40:1653–9.
    1. Wells G, Beaton D, Shea B, Boers M, Simon L, Strand V, et al. Minimal clinically important differences: review of methods. J Rheumatol 2001;28:406–12.
    1. Sandhu SK, Halpern CH, Vakhshori V, Mirsaeedi-Farahani K, Farrar JT, Lee JY. Brief pain inventory—facial minimum clinically important difference. J Neurosurg 2015;122:180–90. 10.3171/2014.8.JNS132547
    1. Salaffi F, Stancati A, Silvestri CA, Ciapetti A, Grassi W. Minimal clinically important changes in chronic musculoskeletal pain intensity measured on a numerical rating scale. Eur J Pain 2004;8:283–91. 10.1016/j.ejpain.2003.09.004
    1. Asher AL, Kerezoudis P, Mummaneni PV, Bisson EF, Glassman SD, Foley KT, et al. Defining the minimum clinically important difference for grade I degenerative lumbar spondylolisthesis: insights from the Quality Outcomes Database. Neurosurg Focus 2018;44:E2.

Source: PubMed

Sponsorer og samarbeidspartnere

Medisinsk tilstand

Legemiddelintervensjoner

3
Abonnere