Nicholas Henschke

Prognosis in patients with recent onset low back pain in Australian primary care: inception cohort study

Objective To estimate the one year prognosis and identify prognostic factors in cases of recent onset low back pain managed in primary care. Design Cohort study with one year follow-up. Setting Primary care clinics in Sydney, Australia. Participants An inception cohort of 973 consecutive primary care patients (mean age 43.3, 54.8% men) with non-specific low back pain of less than two weeks’ duration recruited from the clinics of 170 general practitioners, physiotherapists, and chiropractors. Main outcome measures Participants completed a baseline questionnaire and were contacted six weeks, three months, and 12 months after the initial consultation. Recovery was assessed in terms of return to work, return to function, and resolution of pain. The association between potential prognostic factors and time to recovery was modelled with Cox regression. Results The follow-up rate over the 12 months was more than 97%. Half of those who reduced their work status at baseline had returned to previous work status within 14 days (95% confidence interval 11 to 17 days) and 83% had returned to previous work status by three months. Disability (median recovery time 31 days, 25 to 37 days) and pain (median 58 days, 52 to 63 days) took much longer to resolve. Only 72% of participants had completely recovered 12 months after the baseline consultation. Older age, compensation cases, higher pain intensity, longer duration of low back pain before consultation, more days of reduced activity because of lower back pain before consultation, feelings of depression, and a perceived risk of persistence were each associated with a longer time to recovery. Conclusions In this cohort of patients with acute low back pain in primary care, prognosis was not as favourable as claimed in clinical practice guidelines. Recovery was slow for most patients. Nearly a third of patients did not recover from the presenting episode within a year.

Prognosis for patients with chronic low back pain: inception cohort study

Objectives To describe the course of chronic low back pain in an inception cohort and to identify prognostic markers at the onset of chronicity. Design Inception cohort study with one year follow-up. Setting Primary care clinics in Sydney, Australia. Participants The study sample was a subcohort of an inception cohort of 973 consecutive patients presenting to primary care with acute low back pain (<2 weeks’ duration). 406 participants whose pain persisted for three months formed the inception cohort of patients with chronic low back pain. Main outcome measures Outcomes and putative predictors measured at initial presentation, onset of chronicity (study entry), and follow-up at nine and 12 months. Recovery was determined from measures of pain intensity, disability, and work status. The association between potential prognostic factors and time to recovery was modelled with Cox regression. Results Completeness of follow-up was 97% of total person time for all outcomes. The cumulative probability of being pain-free was 35% at nine months and 42% at 12 months and for complete recovery was 35% at nine months and 41% at 12 months. Of the 259 participants who had not recovered from pain related disability at entry to the chronic study, 47% had recovered by 12 months. Previous sick leave due to low back pain, high disability levels or high pain intensity at onset of chronicity, low levels of education, greater perceived risk of persistent pain, and being born outside Australia were associated with delayed recovery. Conclusion More than one third of patients with recent onset, non-radicular chronic low back pain recover within 12 months. The prognosis is less favourable for those who have taken previous sick leave for low back pain, have high disability levels or high pain intensity at onset of chronic low back pain, have lower education, perceive themselves as having a high risk of persistent pain, and were born outside Australia.

After an episode of acute low back pain, recurrence is unpredictable and not as common as previously thought

Study Design. Inception cohort study. Objective. To provide the first reliable estimate of the 1-year incidence of recurrence in subjects recently recovered from acute nonspecific low back pain (LBP) and to determine factors predictive of recurrence in 1 year. Summary of Background Data. Previous studies provide potentially flawed estimates of recurrence of LBP because they do not restrict the cohort to those who have recovered and are therefore eligible for a recurrence. Methods. We identified 1334 consecutive patients who presented to primary care with acute LBP; of these 353 subjects recovered before 6 weeks and entered the current study. The primary outcome measure was recurrence of LBP in the next year. Specifically, an episode of recurrence was defined in 2 ways: recall of recurrence at the 12-month follow-up and report of pain at the 3- or 12-month follow-up. Risk factors for recurrence were assessed at baseline. Pain intensity was assessed at 6 weeks, 3 months, and 12 months and recurrence at 12 months. Factors that could plausibly affect recurrence were chosen a priori and evaluated using a multivariable regression analysis. Results. Recurrence of LBP was found to be much less common than previous estimates suggest, ranging from 24% (95% CI = 20%–28%) using “12-month recall” definition of recurrence, to 33% (95% CI = 28%–38%) using “pain at follow-up” definition of recurrence. However, only 1 factor, previous episode(s) of LBP, was consistently predictive of recurrence within the next 12 months (odds ratio = 1.8–2.0, P = 0.00–0.05). Conclusion. This study challenges the assumption that the majority of subjects will have a recurrence of LBP in a 1-year period. After the resolution of an episode of acute LBP, about 25% of subjects will have a recurrence in the next year. It is difficult to predict who will have a recurrence within the next year.

Red flags to screen for malignancy and fracture in patients with low back pain: systematic review

Objective To review the evidence on diagnostic accuracy of red flag signs and symptoms to screen for fracture or malignancy in patients presenting with low back pain to primary, secondary, or tertiary care. Design Systematic review. Data sources Medline, OldMedline, Embase, and CINAHL from earliest available up to 1 October 2013. Inclusion criteria Primary diagnostic studies comparing red flags for fracture or malignancy to an acceptable reference standard, published in any language. Review methods Assessment of study quality and extraction of data was conducted by three independent assessors. Diagnostic accuracy statistics and post-test probabilities were generated for each red flag. Results We included 14 studies (eight from primary care, two from secondary care, four from tertiary care) evaluating 53 red flags; only five studies evaluated combinations of red flags. Pooling of data was not possible because of index test heterogeneity. Many red flags in current guidelines provide virtually no change in probability of fracture or malignancy or have untested diagnostic accuracy. The red flags with the highest post-test probability for detection of fracture were older age (9%, 95% confidence interval 3% to 25%), prolonged use of corticosteroid drugs (33%, 10% to 67%), severe trauma (11%, 8% to 16%), and presence of a contusion or abrasion (62%, 49% to 74%). Probability of spinal fracture was higher when multiple red flags were present (90%, 34% to 99%). The red flag with the highest post-test probability for detection of spinal malignancy was history of malignancy (33%, 22% to 46%). Conclusions While several red flags are endorsed in guidelines to screen for fracture or malignancy, only a small subset of these have evidence that they are indeed informative. These findings suggest a need for revision of many current guidelines.

A systematic review identifies five "red flags" to screen for vertebral fracture in patients with low back pain

OBJECTIVE To determine the accuracy of clinical features in diagnosing vertebral fracture in low back pain patients and assess the psychometric properties of the Quality Assessment of Studies of Diagnostic Accuracy Included in Systematic Reviews (QUADAS) scale. STUDY DESIGN AND SETTING A diagnostic systematic review was performed on all available records in MEDLINE, CINAHL, and EMBASE. Studies were considered eligible if they investigated clinical features associated with vertebral fracture in a cohort of low back pain patients. All eligible studies were assessed for methodological quality using the QUADAS scale, and two authors extracted true-positive, true-negative, false-positive, and false-negative data for each clinical feature. RESULTS Twelve studies were identified by the review, investigating 51 clinical features. Five clinical features were useful to raise or lower the probability of vertebral fracture: age>50 years (likelihood ratio [LR]+=2.2, LR-=0.34), female gender (LR+=2.3, LR-=0.67), major trauma (LR+=12.8, LR-=0.37), pain and tenderness (LR+=6.7, LR-=0.44), and a distracting painful injury (LR+=1.7, LR-=0.78). The QUADAS had low internal consistency, and only three items had high inter-rater reliability. There was inadequate reporting of many methodological quality items. CONCLUSION Five clinical features were identified that can be used to screen for vertebral fracture. The psychometric properties of the QUADAS scale raise concerns about its use to rate the quality of low back pain diagnosis studies.

Injection therapy and denervation procedures for chronic low-back pain: a systematic review

Injection therapy and denervation procedures are commonly used in the management of chronic low-back pain (LBP) despite uncertainty regarding their effectiveness and safety. To provide an evaluation of the current evidence associated with the use of these procedures, a systematic review was performed. Existing systematic reviews were screened, and the Cochrane Back Review Group trial register was searched for randomized controlled trials (RCTs) fulfilling the inclusion criteria. Studies were included if they recruited adults with chronic LBP, evaluated the use of injection therapy or denervation procedures and measured at least one clinically relevant outcome (such as pain or functional status). Two review authors independently assessed studies for eligibility and risk of bias (RoB). A meta-analysis was performed with clinically homogeneous studies, and the GRADE approach was used to determine the quality of evidence. In total, 27 RCTs were included, 14 on injection therapy and 13 on denervation procedures. 18 (66%) of the studies were determined to have a low RoB. Because of clinical heterogeneity, only two comparisons could be pooled. Overall, there is only low to very low quality evidence to support the use of injection therapy and denervation procedures over placebo or other treatments for patients with chronic LBP. However, it cannot be ruled out that in carefully selected patients, some injection therapy or denervation procedures may be of benefit.

The Epidemiology and Economic Consequences of Pain

Pain is considered a major clinical, social, and economic problem in communities around the world. In this review, we describe the incidence, prevalence, and economic burden of pain conditions in children, adolescents, and adults based on an electronic search of the MEDLINE and EMBASE databases for articles published from January 1, 2000, through August 1, 2014, using the keywords pain, epidemiology, burden, prevalence, and incidence. The impact of pain on individuals and potential risk factors are also discussed. Differences in the methodology and conduct of epidemiological studies make it difficult to provide precise estimates of prevalence and incidence; however, the burden of pain is unquestionably large. Improved concepts and methods are needed in order to study pain from a population perspective and further the development of pain prevention and management strategies.

Effect of Primary Care–Based Education on Reassurance in Patients With Acute Low Back Pain: Systematic Review and Meta-analysis

IMPORTANCE Reassurance is a core aspect of daily medical practice, yet little is known on how it can be achieved. OBJECTIVE To determine whether patient education in primary care increases reassurance in patients with acute or subacute low back pain (LBP). DATA SOURCES Medline, EMBASE, Cochrane Central Register for Controlled Trials, and PsychINFO databases were searched to June 2014. DESIGN Systematic review and meta-analysis of randomized and nonrandomized clinical trials. STUDY SELECTION To be eligible, studies needed to be controlled trials of patient education for LBP that were delivered in primary care and measured reassurance after the intervention. Eligibility criteria were applied, and studies were selected by 2 independent authors. MAIN OUTCOMES AND MEASURES The primary outcomes were reassurance in the short and long term and health care utilization at 12 months. DATA EXTRACTION AND SYNTHESIS Data were extracted by 2 independent authors and entered into a standardized form. A random-effects meta-analysis tested the effects of patient education compared with usual care on measures of reassurance. To investigate the effect of study characteristics, we performed a preplanned subgroup analysis. Studies were stratified according to duration, content, and provider of patient education. RESULTS We included 14 trials (n=4872) of patient education interventions. Trials assessed reassurance with questionnaires of fear, worry, anxiety, catastrophization, and health care utilization. There is moderate- to high-quality evidence that patient education increases reassurance more than usual care/control education in the short term (standardized mean difference [SMD], -0.21; 95% CI, -0.35 to -0.06) and long term (SMD, -0.15; 95% CI, -0.27 to -0.03). Interventions delivered by physicians were significantly more reassuring than those delivered by other primary care practitioners (eg, physiotherapist or nurse). There is moderate-quality evidence that patient education reduces LBP-related primary care visits more than usual care/control education (SMD, -0.14; 95% CI, -0.28 to -0.00 at a 12-month follow-up). The number needed to treat to prevent 1 LBP-related visit to primary care was 17. CONCLUSIONS AND RELEVANCE There is moderate- to high-quality evidence that patient education in primary care can provide long-term reassurance for patients with acute or subacute LBP.

Musculoskeletal pain in children and adolescents

ABSTRACT Introduction Musculoskeletal (MSK) pain in children and adolescents is responsible for substantial personal impacts and societal costs, but it has not been intensively or systematically researched. This means our understanding of these conditions is limited, and healthcare professionals have little empirical evidence to underpin their clinical practice. In this article we summarise the state of the evidence concerning MSK pain in children and adolescents, and offer suggestions for future research. Results Rates of self-reported MSK pain in adolescents are similar to those in adult populations and they are typically higher in teenage girls than boys. Epidemiological research has identified conditions such as back and neck pain as major causes of disability in adolescents, and in up to a quarter of cases there are impacts on school or physical activities. A range of physical, psychological and social factors have been shown to be associated with MSK pain report, but the strength and direction of these relationships are unclear. There are few validated instruments available to quantify the nature and severity of MSK pain in children, but some show promise. Several national surveys have shown that adolescents with MSK pain commonly seek care and use medications for their condition. Some studies have revealed a link between MSK pain in adolescents and chronic pain in adults. Conclusion Musculoskeletal pain conditions are often recurrent in nature, occurring throughout the life-course. Attempts to understand these conditions at a time close to their initial onset may offer a better chance of developing effective prevention and treatment strategies.

Effects of Air Temperature on Climate-Sensitive Mortality and Morbidity Outcomes in the Elderly; a Systematic Review and Meta-analysis of Epidemiological Evidence

Introduction Climate change and rapid population ageing are significant public health challenges. Understanding which health problems are affected by temperature is important for preventing heat and cold-related deaths and illnesses, particularly in the elderly. Here we present a systematic review and meta-analysis on the effects of ambient hot and cold temperature (excluding heat/cold wave only studies) on elderly (65 + years) mortality and morbidity. Methods Time-series or case-crossover studies comprising cause-specific cases of elderly mortality (n = 3,933,398) or morbidity (n = 12,157,782) were pooled to obtain a percent change (%) in risk for temperature exposure on cause-specific disease outcomes using a random-effects meta-analysis. Results A 1 °C temperature rise increased cardiovascular (3.44%, 95% CI 3.10–3.78), respiratory (3.60%, 3.18–4.02), and cerebrovascular (1.40%, 0.06–2.75) mortality. A 1 °C temperature reduction increased respiratory (2.90%, 1.84–3.97) and cardiovascular (1.66%, 1.19–2.14) mortality. The greatest risk was associated with cold-induced pneumonia (6.89%, 20–12.99) and respiratory morbidity (4.93% 1.54–8.44). A 1 °C temperature rise increased cardiovascular, respiratory, diabetes mellitus, genitourinary, infectious disease and heat-related morbidity. Discussion Elevated risks for the elderly were prominent for temperature-induced cerebrovascular, cardiovascular, diabetes, genitourinary, infectious disease, heat-related, and respiratory outcomes. These risks will likely increase with climate change and global ageing.