Research Review By Dr. Jeff Muir©

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Date Posted:

July 2015

Study Title:

Catastrophizing – a prognostic factor for outcome in patients with low back pain: a systematic review

Authors:

Wertli MM, Eugster R, Held U, et al.

Author's Affiliations:

Department of Internal Medicine, Horten Centre for Patient-Oriented Research and Knowledge Transfer, University of Zurich, Switzerland; NYU Hospital for Joint Diseases, Occupational and Industrial Orthopedic Center (OIOC), New York University, USA.

Publication Information:

The Spine Journal 2014; 14: 2639–2657.

Background Information:

Patients’ attitudes and coping mechanisms seem to play a causal role in the chronification of low back pain (LBP). While most adults will develop low back pain in the course of their lifetime, 10-15% will evolve into chronic LBP (1), which disproportionately accounts for up to 75% of the healthcare costs associated with LBP (2, 3). Optimal treatment includes identification of risk factors for delayed recovery in patients with subacute LBP in order to avoid chronification.

Fear- avoidance beliefs (FAB) and catastrophizing of symptoms (defined as ‘‘an exaggerated negative mental set brought to bear during actual or anticipated painful experience’’ [4]) can contribute to the development of chronic pain. This initiates a deleterious cycle of fear and avoidance of activity, which in turn leads to disuse and distress, reinforcing the negative appraisal of the injury (5). The main obstacle for clinicians in preventing this cascade is the ability to assess patients and identify the potential for catastrophizing.

The aims of this systematic review were to:
  1. Review the existing literature on the role of catastrophizing as a prognostic factor in acute, subacute, and chronic LBP; and
  2. analyze the available data in terms of an optimal cut-off value for the scales used.

Pertinent Results:

Study Selection: From an initial pool of 1473 records, 19 publications based on 16 studies were included in the final analysis.

Study Characteristics:
The majority of studies were prospective cohort studies (9 of 16), of which two publications were based on an RCT and four were based on two separate cohort studies. Study quality ranged between good (4 studies) to moderate (12 studies), due largely to deficits in descriptions of study methodology.

Prognostic Value of Catastrophizing in Acute LBP Patients:
Catastrophizing thoughts were prognostic for an unfavourable outcome and prolonged bed rest at 1 year. It was also associated with a lesser reduction in disability and persisting symptoms at 3 month follow-up.

Prognostic Value of Catastrophizing in Subacute LBP Patients:
Patients using catastrophizing as a coping strategy expressed more pain and disability at 6 months and more disability at 1 year than those who did not. However, no association was found between catastrophizing and work status or sick leave at 3 months and with return-to-work (RTW) after 1 year in three studies.

Prognostic Value of Catastrophizing in Chronic LBP Patients:
Catastrophizing thoughts were not associated with more pain or disability in patients with chronic LBP who had a first- time claim for workers compensation in the United States. Catastrophizing as a coping strategy was associated with more disability at 9 months follow-up in patients participating in a work-hardening program.

Patients with Acute to Chronic LBP Without Subgrouping:
Two prospective cohort studies found catastrophizing thoughts to be associated with more disability at 3 months and 1 year in a mixed group of patients.

Potential Influence of Important Prognostic Factors:
Patients in prognostic studies were older (mean age 44 years compared with 41 years) and seemed to express higher levels of catastrophizing as coping strategy. In studies that applied cut-off values, a dose-dependent likelihood for prognostic findings for catastrophizing (higher values associated with poorer outcome) was present.

Clinical Application & Conclusions:

This review demonstrates the value of addressing fear-avoidance beliefs (FAB), should they be present. Cut-off values for testing were not utilized regularly among studies and, although the value of set cut-off values is unknown, the consensus is that future research should aim to identify appropriate cut-off values for prognostic tests, in order to properly identify patients at risk for chronification of symptoms and initiate appropriate treatments.

In practice, it is important for clinicians to identify at-risk patients and implement appropriate treatments to address FABs, if present. Recognition of catastrophizing thoughts, over-reactions and negative attitudes will help to identify potential FABs, which clinicians will need to immediately address in their treatment plan. Clinical questionnaires such as the Fear Avoidance Beliefs Questionnaire (FABQ) can assist in this process.

Study Methods:

This study utilized the MOOSE (Meta-analysis Of Observational Studies in Epidemiology) recommendations for systematic reviews of observational studies (6).

Search Strategy:
The following databases were searched for observational studies published between January 1980 and September 2012: BIOSIS, CINAHL, Cochrane Library, Embase, OTSeeker, PeDRO, PsycInfo, Medline, Scopus, and Web of Science. Hand searches of the 6 most commonly retrieved journals (Pain, Spine, Journal of Pain, European Journal of Pain, Clinical Journal of Pain, Pain Medicine) were also completed.

Eligibility Criteria:
Studies were eligible for inclusion if:
  1. They reported research concerning patients seeking care for non-specific low back pain,
  2. they demonstrated at least moderate study quality,
  3. they investigated the prognostic value of catastrophizing, and
  4. they were published between January 1980 and September 2012.
Quality Assessment:
The quality of each study was assessed using the Scottish Intercollegiate Guidelines Network (SIGN) Methodology checklist for cohort studies (7).

Psychometric Properties & Questionnaires Utilized:
Several scales are available to measure the evolution of pain to chronic status. For this study, the following scales were identified as valid in eligible studies:
  • The Pain Catastrophizing Scale (PCS)
  • The Coping Strategy Questionnaire (CSQ)
  • The Pain-Related Self-Statement Scale (PRSS)
Statistical Analysis:
Due to the heterogeneity of the study populations and outcome measures, only descriptive statistics were used to summarize findings across all cohort studies for baseline catastrophizing mean values. Whenever possible, reported values (odds ratio, beta coefficient, or hazard ratio and corresponding 95% confidence interval) from multiple analyses were used in the forest plots.

Study Strengths / Weaknesses:

Strengths:
  • The assessment of catastrophizing in light of disease duration, and
  • The comprehensive evaluation of currently available studies.
Limitations:
The study’s main limitation is a possibility of a publication bias because of unpublished negative findings. The authors attempted to account for this by conducting a thorough bibliographic search of all included studies, thus identifying the maximum number of potentially eligible studies.

Additional References:

  1. Balague F, Mannion AF, Pellise F, Cedraschi C. Non-specific low back pain. Lancet 2012; 379: 482–91.
  2. Fourney DR, Andersson G, Arnold PM, et al. Chronic low back pain: a heterogeneous condition with challenges for an evidence-based approach. Spine 2011; 36(21 Suppl): S1–9.
  3. Vos T, Flaxman AD, Naghavi M, et al. Years lived with disability (YLDs) for 1160 sequelae of 289 diseases and injuries 1990- 2010: a systematic analysis for the Global Burden of Disease Study 2010. Lancet 2012; 380: 2163–96.
  4. Hill SA, Balion CM, Santaguida P, et al. Evidence for the use of Btype natriuretic peptides for screening asymptomatic populations and for diagnosis in primary care. Clin Biochem 2008; 41: 240–9.
  5. Linton SJ, Shaw WS. Impact of psychological factors in the experience of pain. Phys Ther 2011; 91: 700–11.
  6. Kole-Snijders AM, Vlaeyen JW, Goossens ME, et al. Chronic low back pain: what does cognitive coping skills training add to operant behavioral treatment? Results of a randomized clinical trial. J Consult Clin Psychol 1999; 67: 931–44.
  7. Harbour R, Lowe G, Twaddle S. Scottish Intercollegiate Guidelines Network: the first 15 years (1993-2008). J R Coll Physicians Edinb 2011; 41: 163–8.