Back Pain Patients In Primary Care Research Articles

Psychophysical Tests as Predictors of Back Pain Chronicity in Primary Care

If persons at risk of developing chronic pain could be identified early in a pain episode, treatment could be tailored on the basis of risk. Responses to psychophysical tests differ in persons with chronic pain vs pain-free controls and thus appear promising as indicators of susceptibility to chronic pain. In a cohort of 157 patients making their first primary care visit during a back pain episode, we explored the relationships of psychophysical test responses (pressure pain thresholds at low back and thenar sites, cold pressor pain ratings, conditioned pain modulation, and mechanical temporal summation) to baseline measures of pain and psychological distress and assessed whether test responses predicted clinically significant back pain 4 months later. Examiner-standardized pressure pain thresholds were significantly (P < .05) correlated with baseline back pain severity and diffuseness of bodily pain (Pearson correlations = −.21 to −.35). Lower baseline pressure pain thresholds significantly predicted back pain at 4 months (odds ratio [95% confidence interval]: low back, .66 [.44, .96]; thenar, .62 [.40, .92]); however, after controlling for participant age and sex, these associations were no longer significant. Cold pressor pain, conditioned pain modulation, and mechanical temporal summation were not significant predictors of 4-month back pain in either model. PerspectiveSome psychophysical test responses have been found to differ in persons with chronic pain vs pain-free controls. In this prospective study, psychophysical test responses had limited utility for predicting which primary care back pain patients would have clinically significant chronic pain 4 months later.

Missing Data and Imputation: A Practical Illustration in a Prognostic Study on Low Back Pain

ObjectiveWhen designing prediction models by complete case analysis (CCA), missing information in either baseline (predictors) or outcomes may lead to biased results. Multiple imputation (MI) has been shown to be suitable for obtaining unbiased results. This study provides researchers with an empirical illustration of the use of MI in a data set on low back pain, by comparing MI with the more commonly used CCA. Effects will be shown of imputing missing information on the composition and performance of prognostic models, distinguishing imputation of missing values in baseline characteristics and outcome data. MethodsData came from the Beliefs about Backpain cohort, a study of psychologic obstacles to recovery in primary care back pain patients in the United Kingdom. Candidate predictors included demographics, back pain characteristics, and psychologic variables. Complete case analysis was compared with MI within patients with complete outcome but missing baseline data (n = 809) and patients with missing baseline or outcome data (n = 1591). Multiple imputation was performed by a Multiple Imputation by Chained Equations procedure. ResultsCases with missing outcome data (n = 782, 49.1%) or with missing baseline data (n = 116, 8%) both differed from complete cases regarding the distribution of some predictors and more often had a poor outcome. When comparing CCA with MI, model composition showed to be affected. ConclusionsComplete case analysis can give biased results, even when only small amounts of data are missing. Now that MI is available in standard statistical software, we recommend that it be used to handle missing data.

Comparing the STarT Back Screening Tool's Subgroup Allocation of Individual Patients With That of Independent Clinical Experts

The STarT Back Screening Tool (SBST) is validated to subgroup primary care patients with back pain into risk groups relevant to initial decision-making. However, it remains unclear how the tool's allocation of individuals compares with subjective clinical decision-making. We evaluated agreement between clinicians and the SBST's allocation to risk subgroups, and explored reasons for differences observed. Twelve primary care back pain patients underwent a video-recorded clinical assessment. The SBST was completed on the same day. Clinical experts (3 general practitioners, 3 physiotherapists, and 3 pain management specialists) individually reviewed the patient videos (4 each), blind to SBST allocation. Their task was to subgroup patients into low, medium, or high-risk groups. Interrater agreement between clinicians was "fair" (κ=0.28), with consistent allocation between experts in 4 of 12 patients. There was observed agreement with the SBST in 17 of 36 cases (47%) and Cohen's weighted κ was 0.22, indicating fair agreement. Two reasons for differences emerged. Clinicians tailor their decisions according to patient expectations and demands for treatment and clinicians use knowledge of difficult life circumstances that may be unrelated back pain. Clinicians make inconsistent risk estimations for primary care patients with back pain when using intuition alone, with little agreement with a formal subgrouping tool. Unlike clinicians, the SBST could not make a sophisticated synthesis of patient preferences, expectations, and previous treatment history. Although acknowledging the limitations of back pain subgrouping tools, more research is needed to test whether their use improves consistency in primary care decision-making.

Contributions of prognostic factors for poor outcome in primary care low back pain patients

Background Back pain is common and some sufferers consult GPs, yet many sufferers develop persistent problems. Combining information on risk of persistence and prognostic indicator prevalence provides more information on potential intervention targets than risk estimates alone. Aims To determine the proportion of primary care back pain patients with persistent problems whose outcome is related to measurable prognostic factors. Methods Prospective cohort study of back pain patients (30–59 years) at five general practices in Staffordshire, UK ( n = 389). Baseline factors (demographic; episode duration; symptom severity; pain widespreadness; anxiety; depression; catastrophising; fear-avoidance; self-rated health) were assessed for their association with disabling and limiting pain after 12-months. The proportion of those with persistent problems whose outcome was related to each factor was calculated. Results Prevalence of prognostic factors ranged from 23% to 87%. Strongest predictors were unemployment (adjusted relative risk (RR) 4.2; 95% CI 2.0, 8.5) and high pain intensity (4.1; 1.7, 9.9). The largest proportions of persistent problems were related to high pain intensity (68%; 95% CI 27, 87%) and unemployment (64%; 33, 82%). Combining these indicated that 85% of poor back pain outcome is related to these two factors. Poor self-rated health, functional disability, upper body pain and pain bothersomeness were related with outcome for over 40% of those with persistent problems. Conclusions Several factors increased risk of poor outcome in back pain patients, notably high pain and unemployment. These risks in combination with high prevalence of risk factors in this population distinguish factors that can help identify targets or sub-groups for intervention.

Subgrouping patients with low back pain in primary care: Are we getting any better at it?

Low back pain is a common, disabling condition with high personal and economic costs. Despite clinical guidelines, there have not been tangible reductions in the population prevalence of back pain or its serious long-term consequences. One reason for this might be that the ‘one-size fits all approach’ advocated by many guidelines fails to target treatments at patients who might benefit the most, thus diluting their potential benefits. Identifying subgroups of patients for whom different treatments are superior has been referred to as the ‘Holy Grail’ of low back pain research. Maximising the potential for targeted interventions is predicated on better understanding of the prognostic factors that are causally related to clinical outcome and identifying which are a) most predictive of outcome and b) most likely to be modifiable. Systematic identification of key obstacles to recovery in primary care back pain patients from high quality epidemiological studies can inform the development of early, targeted interventions. Only then can closer matching of treatments to patient characteristics be a clinical reality. This paper critically reviews progress in subgrouping for targeted treatment for patients with low back pain, identifies the key arguments for and against subgrouping and highlights the attributes of robust approaches in this field.

A prognostic approach to defining chronic pain

This paper develops a prognostic approach to defining chronic back pain. Possible and probable chronic back pain were defined, respectively, by a 50% and an 80% (or greater) probability of future clinically significant back pain. We assessed whether an empirically derived chronic pain classification satisfied these validating criteria among 1213 primary care back pain patients assessed at baseline and at 1, 2 and 5 year follow-ups. From multiple measures of back pain intensity and dysfunction, Latent Transition Regression Analysis empirically identified four pain severity latent classes: no pain; mild pain; moderate pain and limitation; and severe, limiting pain. From one observation point to the next, patients were most likely to remain in the same pain severity class, but chronic pain was better characterized as a dynamic state than a static trait. Among persons with severe, limiting pain, prognostic variables (depression, diffuse pain, pain persistence) improved prediction of future severe, limiting pain. A risk score developed from pain severity and prognostic measures identified risk levels corresponding to 50 and 80% probability thresholds for predicting future clinically significant back pain. At baseline and 1 year, 6.1 and 4.4% of study patients met or exceeded the 80% risk threshold for probable chronic back pain. An additional 20.3% at baseline and 12.5% at 1 year met or exceeded the 50% risk threshold for possible chronic back pain. Defining chronic pain prospectively, by risk thresholds for future clinically significant pain, provides an empirically grounded approach to chronic pain assessment.

Cognitive/behavioral approaches: Fear reduction and activity restoration in back pain patients

Fear of pain/injury and avoidance of physical activity contributes to chronic pain and disability for many back pain patients. Although evidence-based guidelines for back pain recommend physical exercise and resumption of normal activities, practical models for integrating activating interventions into routine care are lacking. This randomized trial assessed such an intervention. After completing a baseline interview, primary care back pain patients were randomly assigned to Intervention (n=119) or Control (n=121) groups. The intervention included two psychologist visits to address pain-related fears, benefits of resuming normal activities, goal setting, action planning, and relapse prevention. Two physical therapy visits included a standardized examination of the back, education and reassurance, teaching of exercises relevant to the action plan, and problem-solving barriers to action plan. Intervention patients received a videotape and book on back pain self-management. The Control group received care as usual. Follow-up telephone interviews were conducted at 2, 6 and 12 months by an interviewer, blind to group assignment. All participants completing at least one follow-up interview were included in analyses regardless of level of intervention participation. Outcome measures included the Roland Disability Questionnaire (RDQ), a shortened version of the Tampa Scale for Kinesiophobia (TSK), the Mental Health Inventory and the Social Functioning scales from the SF-36, and measures of pain intensity, back pain worry, and occupational role disability. The Intervention patients improved more than Control patients on RDQ (p<0.0001), TSK (p<0.0001), back pain worry (p<0.0001), average pain intensity (p=0.0007), and in occupational role activities (p=0.008) over the one-year follow-up. This brief, activating intervention produced enduring reductions in pain-related fear and modest, but sustained improvement of activity limitations. Results are consistent with prior randomized trials, addressing similar content, but utilizing various providers.

A randomized trial of a cognitive-behavioral program for enhancing back pain self care in a primary care setting

Back pain is a significant health care problem that has been managed unsatisfactorily in primary care settings. Providers typically address medical issues but do not adequately address patient concerns or functional limitations related to back pain. We evaluated a brief intervention for primary care back pain patients designed to provide accurate information about back pain, instill attitudes favorable towards self care, reduce fears and worries, assist patients in developing personalized action plans to manage their back pain, and improve functional outcomes. Patients enrolled in a large health maintenance organization were invited to participate in an educational program to improve back pain self care skills 6–8 weeks after a primary care back pain visit. Patients ( n=226) were randomly assigned to a Self Care intervention or to Usual Care, and were assessed at baseline, 3-, 6-, and 12-months. The intervention involved a two-session Self Care group and an individual meeting and telephone conversation with the group leader, a psychologist experienced in chronic pain management. The intervention was supplemented by educational materials (book and videos) supporting active management of back pain. The control group received usual care supplemented by a book on back pain care. Participants assigned to the Self Care intervention showed significantly greater reductions in back-related worry and fear-avoidance beliefs than the control group. Modest, but statistically significant, effects on pain ratings and interference with activities were also observed.

Prediction of physician visits and prescription medicine use for back pain

The primary purpose of this study was to examine the extent to which specific patient attitudes and beliefs about medical care and self-care for back pain predict future healthcare use. An automated database allowed examination of the predictive relationships in two primary care patient samples. In general, beliefs that physicians should find a definitive cause and permanent cure for back pain predicted neither physician visits nor prescription medication fills. Patient attitudes endorsing the benefits of medical treatment for back pain (as opposed to a permanent cure) predicted the use of these specific healthcare services. In a third sample of primary care back pain patients, we assessed whether a four-session self-care intervention modified those attitudes and beliefs shown to predict future healthcare use. The group intervention was associated with changes in attitudes about use of physician services but not medication use. A secondary purpose was to examine initial psychometric properties of a proposed back pain Self-Care Orientation Scale made up of the original 11 items. Factor analyses of the item set yielded three factors, but inconclusive results; the internal consistency of the identified sub-scales was only moderate. However, findings that a subset of items predicted physician visits and prescriptions medication fills, and was sensitive to change following a self-care intervention, suggest avenues for improving measurement of self-care orientation. These findings help clarify specific patient attitudes and beliefs that are related to healthcare utilization and suggest that a subset of these beliefs can be modified through a brief educational intervention.

Back Pain in Primary Care

Outcomes of primary care back pain patients (N = 1128) were studied at 1 year after seeking care. Changes in depression depending on outcome, and predictors of poor outcome were evaluated. Less than one back pain patient in five reported recent onset (first onset within the previous 6 months). One year after seeking care, the large majority of both recent and nonrecent-onset patients reported having back pain in the previous month (69% vs. 82%). A significant minority of both recent and nonrecent-onset patients had either a poor functional outcome (14% vs. 21%) or continuing high intensity pain without appreciable disability (10% vs. 16%). Predictors of poor outcome included pain-related disability, days in pain, lower educational attainment, and female gender. Among initially dysfunctional patients with persistent pain, one half were improved and one third had a good outcome at the 1-year follow-up. Among initially dysfunctional patients who experienced a good outcome, elevated depressive symptoms improved to normal levels at follow-up. The outcome of back pain was predicted by pain-related disability and days in pain rather than by recency of onset, so it may be more meaningful to distinguish characteristic levels of pain intensity, pain-related disability, and pain persistence than to classify patients as acute or chronic.