Risk of mortality in older adults with loss of appetite: An analysis of Medicare fee-for-service data.

OBJECTIVES: Prior research suggested that loss of appetite (LOA) among adults with Medicare fee-for-service (FFS) insurance in the United States increased the risk of mortality within 1 year; those findings were not adjusted for risk factors and confounders. The objective of this study was to compare the risk of mortality among Medicare FFS beneficiaries with LOA to a control group without LOA while controlling or adjusting for age, comorbidities, body mass index (BMI), and weight loss. DESIGN: Retrospective and observational analysis of Medicare FFS health insurance claims data from October 1, 2015 to December 31, 2021. SETTING: Claims from all settings (e.g., hospital inpatient/outpatient, office, assisted living facility, skilled nursing facility, hospice, rehabilitation facility, home) were included in these analyses. PARTICIPANTS: The LOA group included all individuals aged 65-115 years with continuous Medicare FFS medical coverage (Parts A and/or B) for at least 12 months before a claim with ICD-10 diagnosis code "R63.0 Anorexia". The control group was drawn from individuals aged 65-115 years with continuous Medicare FFS coverage who did not have a diagnosis of R63.0. Individuals with LOA were matched 1:3 to those in the control group based on age, sex, and race/ethnicity. MEASUREMENTS: Mortality in the LOA group was compared to mortality in the control group using Kaplan-Meier and Cox regression analyses and stratified or adjusted in terms of Charlson Comorbidity Index (CCI), claims-based frailty index (CFI), BMI, and weight loss. RESULTS: The study population of 1,707,031 individuals with LOA and 5,121,093 controls without LOA was 61.7% female and 82.2% White. More individuals with LOA compared with the control group had a CCI score 5+ (52.4% vs. 19.4%), CFI score 5+ (31.6% vs. 6.4%), and BMI < 20 kg/m2 (11.2% vs. 2.1%). Median follow-up was 12 months (individuals with LOA) and 49 months (control group). In a matched population, the risk of mortality was significantly higher (unadjusted hazard ratio 4.40, 95% confidence interval 4.39-4.42) for individuals with LOA than the control group. Median survival time was 4 months (individuals with LOA) and 26 months (control group); differences in survival time remained when stratifying by CCI, BMI, and weight loss. CONCLUSION: Individuals with LOA had a substantially increased risk of death even after matching for age, sex, race/ethnicity, and adjusting for comorbidities. These findings highlight the burden of illness in older adults with LOA and the need for therapies.

Use of Real-World Evidence to Drive Drug Development Strategy and Inform Clinical Trial Design.

Interest in real-world data (RWD) and real-world evidence (RWE) to expedite and enrich the development of new biopharmaceutical products has proliferated in recent years, spurred by the 21st Century Cures Act in the United States and similar policy efforts in other countries, willingness by regulators to consider RWE in their decisions, demands from third-party payers, and growing concerns about the limitations of traditional clinical trials. Although much of the recent literature on RWE has focused on potential regulatory uses (e.g., product approvals in oncology or rare diseases based on single-arm trials with external control arms), this article reviews how biopharmaceutical companies can leverage RWE to inform internal decisions made throughout the product development process. Specifically, this article will review use of RWD to guide pipeline and portfolio strategy; use of novel sources of RWD to inform product development, use of RWD to inform clinical development, use of advanced analytics to harness "big" RWD, and considerations when using RWD to inform internal decisions. Topics discussed will include the use of molecular, clinicogenomic, medical imaging, radiomic, and patient-derived xenograft data to augment traditional sources of RWE, the use of RWD to inform clinical trial eligibility criteria, enrich trial population based on predicted response, select endpoints, estimate sample size, understand disease progression, and enhance diversity of participants, the growing use of data tokenization and advanced analytical techniques based on artificial intelligence in RWE, as well as the importance of data quality and methodological transparency in RWE.

Economic Evaluation of an Extended Telehealth Worksite Exercise Intervention to Reduce Lost Work Time from Low Back Pain in Career Firefighters.

Purpose Low back pain (LBP) is a leading cause of lost work time (LWT) in firefighters and is related to poor muscle endurance. Although exercise can improve muscle endurance, it must be continued to sustain benefits, and it is unknown if it can reduce LWT. This study conducted an economic evaluation of an extended worksite exercise intervention in career firefighters. Methods A randomized controlled trial allocated 264 firefighters to telehealth with remote instruction ("telehealth"), direct exercise supervision ("direct"), or brief education ("control"). The telehealth and direct groups performed worksite exercises twice weekly for 12 months. Outcomes included quality adjusted life years, LWT from LBP (24-h shifts), costs of LWT from LBP, and net monetary benefits. Results A total of 216 firefighters were included in the economic analysis (telehealth n = 71, direct n = 75, control n = 70). Sixteen experienced LWT from LBP (telehealth n = 4, direct n = 4, control n = 8). The mean number of 24-h shifts lost from LBP were 0.05 (telehealth), 0.28 (direct), and 0.43 (control). Mean study intervention costs per participant were $1984 (telehealth), $5269 (direct), and $384 (control). Net monetary benefit was $3573 for telehealth vs. direct, - $1113 for telehealth vs. control, and - $4686 for direct vs. control. Conclusions Worksite exercise reduced LWT from LBP in firefighters. Telehealth was less costly and more effective at reducing LWT from LBP than direct exercise supervision. If the costs of telehealth were further reduced, a positive net monetary benefit might also be achieved when compared to no intervention.Clinical trial registration: (clinicaltrials.gov): NCT02362243.

Impact of liposomal bupivacaine on opioid use, hospital length of stay, discharge status, and hospitalization costs in patients undergoing total hip arthroplasty.

Aims: Effective postsurgical analgesia hastens recovery, reduces hospital length of stay (LOS), and decreases hospitalization costs for total hip arthroplasty (THA). Improving these outcomes is critical for value-based surgical bundled payment programs such as the Medicare Comprehensive Care for Joint Replacement and similar programs for commercial insurance providers. This study compared clinical outcomes and hospitalization costs for patients undergoing THA with and without liposomal bupivacaine (LB).Materials and methods: This retrospective, comparative cohort study used data from the Premier Healthcare Database from the 10 hospitals with highest use of LB for THA from January 2011 through April 2017. A cohort undergoing THA with LB at those hospitals was compared with a propensity-score matched cohort at those hospitals who had THA without LB. Descriptive, univariate, and multivariable analyses compared post-surgical inpatient opioid consumption, hospital LOS, discharge status, same-hospital readmissions, and total hospitalization costs. Analyses were performed using the Pearson Chi-square test (categorical variables) and Wilcoxon or Student t-test (continuous variables).Results: For patients with Medicare (with LB, n = 3622; without LB, n = 3610) and commercial insurance (with LB, n = 2648; without LB, n = 2709), use of LB was associated with lower post-surgical inpatient opioid consumption (105 and 81 mg, respectively; p < 0.0001), a 0.7-day shorter LOS (p < 0.0001), a 1.6-1.7-fold increased likelihood of home discharge (p < 0.0001), and no increase in readmissions (p ≥ 0.103). Total hospitalization costs were $561 lower with LB in the Medicare population (p < 0.0001) and $41 higher with LB in the commercial population (p = 0.7697).Limitations: Hospitalization costs were estimated from the hospital chargemaster. Findings from these 10 hospitals may not represent other US hospitals.Conclusions: At select hospitals, THA with LB was associated with reduced post-surgical inpatient opioid consumption, shorter hospital LOS, increased likelihood of home discharge, and lower hospitalization costs. Post-surgical pain management with LB may help hospitals in value-based bundled payment programs.

Impact of treatment with liposomal bupivacaine on hospital costs, length of stay, and discharge status in patients undergoing total knee arthroplasty at high-use institutions.

Aims: Post-surgical pain experienced by patients undergoing total knee arthroplasty (TKA) can be severe. Enhanced recovery after surgery programs incorporating multimodal analgesic regimens have evolved in an attempt to improve patient care while lowering overall costs. This study examined clinical and economic outcomes in hospitals using liposomal bupivacaine (LB) for pain control following TKA.Methods: This retrospective observational study utilized hospital chargemaster data from the Premier Healthcare Database from January 2011 through April 2017 for the 10 hospitals with the highest number of primary TKA procedures using LB. Within these hospitals, patients undergoing TKA who received LB were propensity-score matched in a 1:1 ratio to a control group not receiving LB. Outcomes included hospital length of stay (LOS), discharge status, 30-day same-hospital readmissions, total hospitalization costs, and opioid consumption; only patients with Medicare or commercial insurance as the primary payer for TKA were considered.Results: The study population included 20,907 Medicare-insured patients (LB = 10,411; control =10,496) and 12,505 patients with commercial insurance (LB = 6,242; control = 6,263). Overall, LOS was 0.6 days shorter with LB (p < 0.0001), and patients who received LB were 1.6-times more likely to be discharged home (p < 0.0001). Total hospitalization costs for the TKA procedure were lower with LB for patients with both Medicare (-$616; P < 0.0001) and commercial insurance (-$775; p < 0.0001). Opioid consumption was lower with LB in both payer populations (p < 0.0001). No significant differences for 30-day readmissions were found.Limitations: Costs were estimated using Premier charge-to-cost ratios and limited to goods and services recorded in the chargemaster. Findings from these 10 hospitals may not be representative of other US hospitals.Conclusions: In a sub-set of 10 US hospitals with the highest use of LB for TKA, LB use was associated with shorter hospital LOS, increased home discharge, lower total hospitalization costs, and decreased opioid use after TKA.

Medication, equipment, and supply costs for common interventions providing extended post-surgical analgesia following total knee arthroplasty in US hospitals.

AIMS: To estimate the cost to hospitals of materials (i.e. medications, equipment, and supplies) required to administer common interventions for post-surgical analgesia after total knee arthroplasty (TKA), including single-injection peripheral nerve block (sPNB), continuous peripheral nerve block (cPNB), periarticular infiltration of multi-drug cocktails, continuous epidural analgesia, intravenous patient-controlled analgesia (IV PCA), and local infiltration of bupivacaine liposome injectable suspension (BLIS). MATERIALS AND METHODS: This analysis was conducted using a mixed methods approach combining published literature, publicly available data sources, and administrative data, to first identify the materials required to administer these interventions, and then estimate the cost to the hospital of those materials. Medication costs were estimated primarily using the Wholesale Acquisition Costs (WAC), the cost of reusable equipment was obtained from published sources, and costs for disposable supplies were obtained from the US Government Services Administration (GSA) database. Where uncertainty existed about the technique used when administering these interventions, costs were calculated for multiple scenarios reflecting different assumptions. RESULTS: The total cost of materials (i.e. medications, equipment, and supplies) required to provide post-surgical analgesia was $41.88 for sPNB with bupivacaine; $756.57 for cFNB with ropivacaine; $16.38 for periarticular infiltration with bupivacaine, morphine, methylprednisolone, and cefuroxime; $453.84 for continuous epidural analgesia with fentanyl and ropivacaine; $178.94 for IV PCA with morphine; and $319.00 for BLIS. LIMITATIONS: This analysis did not consider the cost of healthcare providers required to administer these interventions. In addition, this analysis focused on the cost of materials and, therefore, did not consider aspects of relative efficacy or safety, or how the choice of intervention for post-surgical analgesia might impact outcomes such as length of stay, re-admissions, discharge status, adverse events, or total hospitalization costs. CONCLUSIONS: This study provided an estimate of the costs to hospitals for materials required to administer commonly used interventions for post-surgical analgesia after TKA.

A systematic review comparing the costs of chiropractic care to other interventions for spine pain in the United States.

BACKGROUND: Although chiropractors in the United States (US) have long suggested that their approach to managing spine pain is less costly than other health care providers (HCPs), it is unclear if available evidence supports this premise. METHODS: A systematic review was conducted using a comprehensive search strategy to uncover studies that compared health care costs for patients with any type of spine pain who received chiropractic care or care from other HCPs. Only studies conducted in the US and published in English between 1993 and 2015 were included. Health care costs were summarized for studies examining: 1. private health plans, 2. workers' compensation (WC) plans, and 3. clinical outcomes. The quality of studies in the latter group was evaluated using a Consensus on Health Economic Criteria (CHEC) list. RESULTS: The search uncovered 1276 citations and 25 eligible studies, including 12 from private health plans, 6 from WC plans, and 7 that examined clinical outcomes. Chiropractic care was most commonly compared to care from a medical physician, with few details about the care received. Heterogeneity was noted among studies in patient selection, definition of spine pain, scope of costs compared, study duration, and methods to estimate costs. Overall, cost comparison studies from private health plans and WC plans reported that health care costs were lower with chiropractic care. In studies that also examined clinical outcomes, there were few differences in efficacy between groups, and health care costs were higher for those receiving chiropractic care. The effects of adjusting for differences in sociodemographic, clinical, or other factors between study groups were unclear. CONCLUSIONS: Although cost comparison studies suggest that health care costs were generally lower among patients whose spine pain was managed with chiropractic care, the studies reviewed had many methodological limitations. Better research is needed to determine if these differences in health care costs were attributable to the type of HCP managing their care.

A systematic review of diagnostic imaging use for low back pain in the United States.

BACKGROUND CONTEXT: Various studies have reported on the increasing use and costs of diagnostic imaging for low back pain (LBP) in the United States. However, it is unclear whether the methods used in these studies allowed for meaningful comparisons or whether the reported use data can be used to develop evidence-based use benchmarks. PURPOSE: The primary purpose of this study was to review previous estimates of the use of diagnostic imaging for LBP in the United States. STUDY DESIGN/SETTING: The study design is a systematic review of published literature. METHODS: A search through May 2012 was conducted using keywords and free text terms related to health services and LBP in Medline and Health Policy Reference; results were screened for relevance independently, and full-text studies were assessed for eligibility. Only studies published in English since the year 2000 reporting on use of diagnostic imaging for LBP using claims data from the United States were included. Reporting quality was assessed using a modified Downs and Black tool for observational studies. RESULTS: The search strategy yielded 1,102 citations, seven of which met the criteria for eligibility. Studies reported use from commercial health plans (N=4) and Medicare (N=3), with sample sizes ranging from 13,760 to 740,467 members with LBP from specific states or across the United States. The number of diagnostic codes used to identify nonspecific LBP ranged from 2 to 66; other heterogeneity was noted in the methods used across these studies. In commercial health plans, use of radiography occurred in 12.0% to 32.2% of patients with LBP, magnetic resonance imaging (MRI) was used in 16.0% to 21.0%, computed tomography (CT) was used in 1.4% to 3.0%, and MRI and/or CT was used in 10.9% to 16.1%. Findings in Medicare populations were 22.9% to 48.2% for radiography, 11.6% for MRI, and 10.4% to 16.3% for MRI and/or CT. CONCLUSIONS: The reported use of diagnostic imaging for LBP varied across the studies reviewed; differences in methodology made meaningful comparisons difficult. Standardizing methods for performing and reporting analyses of claims data related to use could facilitate efforts by third-party payers, health care providers, and researchers to identify and address the perceived overuse of diagnostic imaging for LBP.

Advancements in the management of spine disorders.

Spinal disorders and especially back and neck pain affect more people and have greater impact on work capacity and health-care costs than any other musculoskeletal condition. One of the difficulties in reducing the burden of spinal disorders is the wide and heterogeneous range of specific diseases and non-specific musculoskeletal disorders that can involve the spinal column, most of which manifest as pain. Despite, or perhaps because of its impact, spinal disorders remain one of the most controversial and difficult conditions for clinicians, patients and policymakers to manage. This paper provides a brief summary of advances in the understanding of back and neck pain over the past decade as evidenced in the current literature. This paper includes the following sections: a classification of spinal disorders; the epidemiology of spine pain in the developed and developing world; key advancements in biological and biomechanical sciences in spine pain; the current status of potential methods for the prevention of back and neck pain; rheumatological and systemic disorders that impact the spine; and evidence-based surgical and non-surgical management of spine pain. The final section of this paper looks to the future and proposes actions and strategies that may be considered by the international Bone and Joint Decade (BJD), by providers, institutions and by policymakers so that we may better address the burden of spine disorders at global and local levels.

Commentary: Laboring to understand the economic impact of spinal disorders.

COMMENTARY ON: Schofield DJ, Shrestha RN, Percival R, et al. The personal and national costs of early retirement because of spinal disorders: impacts on income, taxes, and government support payments. Spine J 2012;12:1111-8 (in this issue).

Causal assessment of workplace manual handling or assisting patients and low back pain: results of a systematic review.

BACKGROUND CONTEXT: Low back pain (LBP) is a common musculoskeletal disorder associated with a considerable social and economic burden within the working-age population. Despite an unclear etiology, numerous physical activities are suspected of leading to LBP. Declaring a causal relationship between occupational activities and LBP remains challenging and requires a methodologically rigorous approach. PURPOSE: To conduct a systematic review focused on assessing the potentially causal relationship between workplace manual handling or assisting patients and LBP. STUDY DESIGN: Systematic review of the literature. SAMPLES: Studies reporting an association between workplace manual handling or assisting patients and LBP. OUTCOME MEASURES: Numerical association between different levels of exposure to manual handling or assisting patients, and the presence or severity of LBP. METHODS: A systematic review was conducted using Medline, EMBASE, CINAHL, Cochrane Library, and Occupational Safety and Health database, gray literature, hand-searching occupational health journals, reference lists of included studies, and content experts. The methodological quality of each study was assessed using a modified Newcastle-Ottawa Scale (NOS) for observational studies. The overall level of evidence supporting various Bradford-Hill criteria for causality for each category of manual handling or assisting patients and type of LBP was then evaluated. Studies were deemed of higher quality if they received a score of five or more on the modified NOS and used appropriate statistical analysis methods. RESULTS: This search yielded 2,766 citations, and 32 studies met the eligibility criteria. Three high-quality studies reported on manual handling and LBP, including two prospective cohorts and one cross-sectional design. None demonstrated a significant association in most of their multivariate risk estimates. One study was able to assess dose-response and temporality, but its results did not support these criteria. Only one study discussed the biological plausibility of this association. Four high-quality studies evaluated assisting patients and LBP, including two case-controls, one cross-sectional, and one prospective cohort design. These studies were consistent in reporting no significant association. Two studies demonstrated a nonsignificant dose-response trend, and two studies discussed the biological plausibility of this association. No studies were able to demonstrate the temporality or experiment criteria. CONCLUSIONS: The studies reviewed did not support a causal association between workplace manual handling or assisting patients and LBP in a Bradford-Hill framework. Conflicting evidence in specific subcategories of assisting patients was identified, suggesting that tasks such as assisting patients with ambulation may possibly contribute to LBP. It appears unlikely that workplace manual handling or assisting patients is independently causative of LBP in the populations of workers studied.

Causal assessment of occupational carrying and low back pain: results of a systematic review.

BACKGROUND CONTEXT: Occupational low back pain (LBP) is a common musculoskeletal disorder that results in high healthcare use and a heavy societal burden from morbidity and medical costs. The etiology of LBP is unclear, although numerous physical activities in the workplace have been implicated in its development. Determining the causal relationship between LBP and specific occupational activities requires a rigorous methodological approach. PURPOSE: To conduct a systematic review of the scientific literature focused on establishing a causal relationship between occupational carrying and LBP. STUDY DESIGN: Systematic review of the literature was performed. SAMPLE: Studies reporting an association between occupational carrying and LBP. OUTCOME MEASURES: Numerical association between different levels of exposure to occupational carrying and the presence or severity of LBP. METHODS: A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship between occupational carrying and LBP by using the commonly used Bradford-Hill framework. The literature was searched using Medline, Embase, CINAHL, Cochrane Library, the Occupational Safety and Health (OSH-ROM) database, gray literature (eg, studies not published in peer-reviewed journals), hand-searching occupational health journals, reference lists of included studies, and content experts. Study quality was evaluated using a modified version of the Newcastle-Ottawa Scale. Levels of evidence supporting specific Bradford-Hill criteria were evaluated for different categories of carrying and types of LBP outcomes. RESULTS: This search yielded 2,766 citations. A total of nine high-quality studies reported on occupational carrying and LBP, including four case-control studies and five prospective cohort studies. These nine studies reported strong and consistent evidence against a statistical association between carrying and LBP. Three studies assessed dose-response, of which only one reported a dose-response trend that was not statistically significant. Five studies were able to assess temporality, but none reported results fulfilling this aspect of causality. The biological plausibility of carrying and LBP was not discussed in any of the nine studies. None of these studies attempted to evaluate the experiment criterion by devising studies in which the exposure to carrying and level of LBP could be measured before and after implementing a strategy aimed at reducing carrying in the workplace to determine its effect on LBP. CONCLUSIONS: This review failed to identify high-quality studies that supported any of the Bradford-Hill criteria to establish causality between occupational carrying and LBP. Based on these results, it is unlikely that occupational carrying is independently causative of LBP in the populations of workers studied.

Synthesis of recommendations for the assessment and management of low back pain from recent clinical practice guidelines.

BACKGROUND CONTEXT: Low back pain (LBP) is a prevalent, costly, and challenging condition to manage. Clinicians must choose among numerous assessment and management options. Several recent clinical practice guidelines (CPGs) on LBP have attempted to inform these decisions by evaluating and summarizing the best available supporting evidence. The quality and consistency of recommendations from these CPGs are currently unknown. PURPOSE: To conduct a systematic review of recent CPGs and synthesize their recommendations on assessing and managing LBP for clinicians. STUDY DESIGN/SETTING: Systematic review. METHODS: Literature search using MEDLINE, National Guidelines Clearinghouse, National Institute for Clinical Excellence, Internet search engines, and references of known articles. Only CPGs related to both assessment and management of LBP written in English were eligible; CPGs that summarized evidence from before the year 2000 were excluded. Data related to methods and recommendations for assessment and management of LBP were abstracted independently by two reviewers. Methodological quality was assessed using the Appraisal of Guidelines Research and Evaluation (AGREE) instrument by two reviewers. RESULTS: The search uncovered 669 citations, of which 95 were potentially relevant and 10 were included in the review; 6 discussed acute LBP, 6 chronic LBP, and 6 LBP with neurologic involvement. Methods used to develop CPGs varied, but the overall methodological quality was high as defined by AGREE scores. Recommendations for assessment of LBP emphasized the importance of ruling out potentially serious spinal pathology, specific causes of LBP, and neurologic involvement, as well as identifying risk factors for chronicity and measuring the severity of symptoms and functional limitations, through the history, physical, and neurologic examination. Recommendations for management of acute LBP emphasized patient education, with short-term use of acetaminophen, nonsteroidal anti-inflammatory drugs, or spinal manipulation therapy. For chronic LBP, the addition of back exercises, behavioral therapy, and short-term opioid analgesics was suggested. Management of LBP with neurologic involvement was similar, with additional consideration given to magnetic resonance imaging or computed tomography to identify appropriate candidates willing to undergo epidural steroid injections or decompression surgery if more conservative approaches are not successful. CONCLUSIONS: Recommendations from several recent CPGs regarding the assessment and management of LBP were similar. Clinicians who care for patients with LBP should endeavor to adopt these recommendations to improve patient care. Future CPGs may wish to invite coauthors from targeted clinician user groups, increase patient participation, update their literature searches before publication, conduct their own quality assessment of studies, and consider cost-effectiveness and other aspects in their recommendations more explicitly.

Causal assessment of occupational pushing or pulling and low back pain: results of a systematic review.

BACKGROUND CONTEXT: Low back pain (LBP) is a prevalent and expensive musculoskeletal condition that predominantly occurs in working-age individuals of industrialized nations. Although numerous occupational physical activities have been implicated in its etiology, determining the causation of occupational LBP still remains a challenge. PURPOSE: To conduct a systematic review evaluating the causal relationship between occupational pushing or pulling and LBP. STUDY DESIGN: Systematic review of the literature. SAMPLE: Studies reporting an association between occupational pushing or pulling and LBP. OUTCOME MEASURES: Numerical association between exposure to pushing or pulling and the presence of LBP. METHODS: A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship, according to Bradford-Hill criteria for causation for occupational pushing or pulling and LBP. A search was conducted using Medline, EMBASE, CINAHL, Cochrane Library, and OSH-ROM, gray literature, hand-searching occupational health journals, reference lists of included studies, and expert knowledge. Methodological quality was assessed using a modified Newcastle-Ottawa Scale. RESULTS: This search yielded 2,766 citations. Thirteen studies met the inclusion criteria. Eight were high-quality studies and five were low-quality studies. There was conflicting evidence with one high-quality study demonstrating a positive association between occupational pushing or pulling and LBP and five studies showing no relationship. One study reported a nonstatistically significant dose-response trend, four studies discussed temporality of which one indicated a positive finding, two studies discussed the biological plausibility of a causal link between occupational pushing or pulling and LBP, and no evidence was uncovered to assess the experiment criterion. CONCLUSIONS: A qualitative summary of existing studies was not able to find any high-quality studies that fully satisfied any of the Bradford-Hill causation criteria for occupational pushing or pulling and LBP. Based on the evidence reviewed, it is unlikely that occupational pushing or pulling is independently causative of LBP in the populations of workers studied.

Causal assessment of occupational lifting and low back pain: results of a systematic review.

BACKGROUND CONTEXT: Low back pain (LBP) is a disorder that commonly affects the working population, resulting in disability, health-care utilization, and a heavy socioeconomic burden. Although the etiology of LBP remains uncertain, occupational activities have been implicated. Evaluating these potentially causal relationships requires a methodologically rigorous approach. Occupational repetitive and/or heavy lifting is widely thought to be a risk factor for the development of LBP. PURPOSE: To conduct a systematic review of the scientific literature to evaluate the causal relationship between occupational lifting and LBP. STUDY DESIGN: Systematic review of the literature. SAMPLE: Studies reporting an association between occupational lifting and LBP. OUTCOME MEASURES: Numerical association between different levels of exposure to occupational lifting and the presence or severity of LBP. METHODS: A search was conducted using Medline, EMBASE, CINAHL, Cochrane Library, OSH-ROM, gray literature (eg, reports not published in scientific journals), hand-searching occupational health journals, reference lists of included studies, and content experts. Evaluation of study quality was performed using a modified version of the Newcastle-Ottawa Scale. Levels of evidence were evaluated for specific Bradford-Hill criteria (association, dose-response, temporality, experiment, and biological plausibility). RESULTS: This search yielded 2,766 citations, of which 35 studies met eligibility criteria and 9 were considered high methodological quality studies, including four case-controls and five prospective cohorts. Among the high-quality studies, there was conflicting evidence for association with four studies reporting significant associations and five studies reporting nonsignificant results. Two of the three studies that assessed dose-response demonstrated a nonsignificant trend. There were no significant risk estimates that demonstrated temporality. No studies were identified that satisfied the experiment criterion. Subgroup analyses identified certain types of lifting and LBP that had statistically significant results, but there were none that satisfied more than two of the Bradford-Hill criteria. CONCLUSIONS: This review uncovered several high-quality studies examining a relationship between occupational lifting and LBP, but these studies did not consistently support any of the Bradford-Hill criteria for causality. There was moderate evidence of an association for specific types of lifting and LBP. Based on these results, it is unlikely that occupational lifting is independently causative of LBP in the populations of workers studied. Further research in specific subcategories of lifting would further clarify the presence or absence of a causal relationship.

Causal assessment of occupational standing or walking and low back pain: results of a systematic review.

BACKGROUND CONTEXT: Low back pain (LBP) is a widespread musculoskeletal condition that frequently occurs in the working-age population. Numerous occupational physical activities have been implicated in its etiology. PURPOSE: To conduct a systematic review establishing a causal relationship between occupational standing or walking and LBP. STUDY DESIGN: Systematic review of the literature. SAMPLE: Studies reporting an association between occupational standing or walking and LBP. OUTCOME MEASURES: Numerical association between exposure to standing or walking and the presence of LBP. METHODS: A systematic review was performed to identify, evaluate, and summarize the literature related to establishing a causal relationship, according to Bradford-Hill criteria for causality, between occupational standing or walking and LBP. A search was conducted using MEDLINE, Embase, CINAHL, Cochrane Library, and Occupational Safety and Health database, gray literature, hand-searching occupational health journals, reference lists of included studies, and expert knowledge. Evaluation of methodological quality was performed using a modified Newcastle-Ottawa Scale. RESULTS: This search yielded 2,766 citations. Eighteen studies met the inclusion criteria. Five were high-quality studies related to standing, and two were high-quality studies related to walking. For occupational standing and LBP, there was moderate to strong evidence against the association criterion, the only study examining dose response did not support this criterion, four studies examining temporality failed to support this criterion, and only one study discussed the biological plausibility criterion. For occupational walking and LBP, there was moderate evidence against a causal relationship with respect to the association, temporality, dose response, and biological plausibility criteria. No studies assessed the experiment criterion for these activities. CONCLUSIONS: A summary of existing studies was not able to find any high-quality studies that satisfied more than two of the Bradford-Hill causation criteria for occupational standing or walking and LBP. Based on the evidence reviewed, it is unlikely that occupational standing or walking is independently causative of LBP in the populations of workers studied.