Search Results for: GPG: Versione 5.7.5 (Novembre 2021)

Stroke, Ahead of Print. BACKGROUND:The efficacy of minimally invasive surgery (MIS) in improving outcomes after nontraumatic intracerebral hemorrhage (ICH) remains uncertain, with inconsistent findings from randomized clinical trials. Our objective was to evaluate the real-world impact of MIS on ICH outcomes using a nationally representative cohort.METHODS:We performed a retrospective cohort study of patients with a nontraumatic ICH enrolled in the American Heart Association Get With The Guidelines-Stroke Registry between January 1, 2011, and December 31, 2021. We excluded patients with a diagnosis of ischemic stroke or other intracranial hemorrhage subtypes, those who underwent open craniotomy or craniectomy, and patients transferred to another hospital. The exposure was MIS, defined as a composite of stereotactic surgical evacuation and endoscopic surgical evacuation. The primary outcome was in-hospital mortality, while secondary outcomes included functional outcomes at discharge (discharge disposition, ambulatory status, and modified Rankin Scale score). We matched patients who underwent MIS with nonsurgical patients using overlap propensity matching and used multiple logistic regression to study the association between MIS and outcomes.RESULTS:Among 684 467 patients with ICH, 555 964 were included; the mean age was 68 (SD, 15.3) years, and 262 999 (47.3%) were female. MIS was performed in 703 patients of whom 312 had stereotactic surgery and 391 had endoscopic surgery. In the matched cohort, in-hospital deaths occurred in 60 of 446 (13.5%) with MIS and 8321 of 35 361 patients (23.5%) without surgery. In regression analyses, MIS was associated with lower in-hospital mortality (adjusted odds ratio, 0.50 [95% CI, 0.39–0.65]) and favorable discharge disposition (adjusted odds ratio, 1.93 [95% CI, 1.61–2.32]) but not with ambulatory status or functional outcomes. In additional analyses, stereotactic surgery and endoscopic surgery were independently associated with lower mortality.CONCLUSIONS:In a large diverse cohort of patients with ICH, MIS was associated with lower in-hospital mortality and favorable discharge disposition. These findings support efforts to understand the durable impact of MIS in patients with ICH.

Stroke, Ahead of Print. BACKGROUND:Recent randomized control trials have demonstrated the efficacy and safety of middle meningeal artery embolization (MMAE) as an adjunct to conventional management for patients with nonacute subdural hematoma (SDH); however, a large majority of trial participants received surgical evacuation as part of the standard of care. Thus, the efficacy and safety of standalone MMAE compared with conservative management (CM) for patients with nonsurgical SDH are unclear.METHODS:This was a retrospective cohort study of the 2019 to 2021 Nationwide Readmissions Database in the United States. Patients with nonsurgical nontraumatic SDH were identified, and MMAE patients were matched with similar CM patients using propensity score matching calculated from demographics, comorbidities, and initial hospitalization outcomes. Patients were followed up to 300 days. The primary end point was composite surgical rescue or death, and secondary end points included surgical rescue and all-cause mortality by 180 days.RESULTS:24 465 patients with nonsurgical nontraumatic SDH were identified; 2228 (9.1%) underwent MMAE. After propensity score matching, 6675 patients remained in the CM group and 2217 in the MMAE group. At 180 days, MMAE patients had a significantly lower risk of surgery or death compared with CM (8.2% versus 10.9%; relative risk, 0.75 [95% CI, 0.59–0.96];P=0.022) and lower risk of death (1.1% versus 3.0%; relative risk, 0.38 [95% CI, 0.17–0.86];P=0.020). Rates of surgical rescue among MMAE and CM patients at 180 days were similar (7.1% versus 8.4%; relative risk, 0.85 [95% CI, 0.63–1.14];P=0.27). Time-to-event analyses for the entire 300-day study follow-up period confirmed that while MMAE was associated with a lower cumulative risk of all-cause mortality (hazard ratio, 0.55 [95% CI, 0.35–0.87];P=0.010), it was not associated with a different risk of surgical rescue (hazard ratio, 1.00 [95% CI, 0.76–1.31];P=1.00).CONCLUSIONS:Standalone MMAE may be beneficial for patients with nonsurgical nontraumatic SDH by reducing the long-term risk of all-cause mortality.

Stroke, Ahead of Print. BACKGROUND:Nonverbal cognitive deficits in poststroke aphasia remain poorly understood. They may result from direct stroke damage or disconnections of preserved cortical regions due to white matter injury, which may be worsened by white matter hyperintensities (WMH). Here, we examined the prevalence of nonverbal cognitive deficits in chronic poststroke aphasia and whether WMH-related disconnections contribute to these deficits beyond those caused by stroke lesions.METHODS:Individuals with chronic left hemisphere ischemic or hemorrhagic stroke were enrolled between 2012 and 2021. Nonverbal cognition was assessed using the Matrix Subtest of the Wechsler Adult Intelligence Scale Version IV, the Pyramids and Palm Trees Test, and the Kissing and Dancing Test. Stroke lesions and WMH masks were derived from structural magnetic resonance imaging scans. Disconnection severity from stroke lesions and WMH was quantified across association, commissural, and projection fibers using the Lesion Quantification Toolbox. Hierarchical regression models examined whether WMH-related disconnections explained additional variance in nonverbal cognitive deficits.RESULTS:Among 73 participants (mean age, 59.1±11.9 years; 61.6% male; mean time poststroke, 47.3±52.4 months), nonverbal cognitive deficits were common (Wechsler Adult Intelligence Scale, 27/58 [46.6%]; Pyramids and Palm Trees Test, 44/73 [60.3%]; Kissing and Dancing Test, 32/61 [52.5%]). Lesion-related commissural disconnections were associated with worse Kissing and Dancing Test performance (r[61]=−0.378;P=0.004), whereas WMH-related disconnections across all fiber types were linked to lower Pyramids and Palm Trees Test scores (r[73]=−0.392 to −0.462;P

Objectives
To assess the prevalence of SARS-CoV-2 antibodies in the residents of Kibera informal settlement in Nairobi, Kenya, before vaccination became widespread, and explore demographic and health-related risk factors for infection.

Design
A cross-sectional study.

Setting
Kibera informal settlement, Nairobi, Kenya.

Participants
Residents of Kibera informal settlement between October 2019 and August 2021, age 1 year and above who reported no current symptoms of COVID-19.

Main outcome measures
Associations were determined between SARS-CoV-2 positive tests measured with one rapid test and two ELISAs and demographic and health-related factors, using Pearson’s 2 test. Crude OR and adjusted OR were calculated to quantify the strength of associations between variables and seropositive status.

Results
A total of 438 participants were recruited. Most (79.2%) were age 18–50 years; females (64.2%) exceeded males. More than one-third (39.1%) were unemployed; only 7.4% were in formal, full-time employment. Less than one-quarter (22.1%) self-reported any underlying health conditions. Nearly two-thirds (64.2%) reported symptoms compatible with COVID-19 in the previous 16 months; only one (0.23%) had been hospitalised with a reported negative COVID-19 test. 370 (84.5%) participants tested positive in any of the three tests. There was no significant difference in SARS-CoV-2 seropositivity across age, sex, presence of underlying health conditions, on medication or those ever tested for SARS-CoV-2. Multiple logistic regression analysis showed that COVID-19 symptoms in the previous 16 months were the only significant independent predictor of seropositivity (p=0.0085).

Conclusion
High SARS-CoV-2 exposure with limited morbidity was found in the residents of Kibera informal settlement. The study confirms other reports of high SARS-CoV-2 exposure with limited morbidity in slum communities. Reasons cited include the high infectious disease burden on the African continent, demographic age structure and underreporting due to limited testing and lack of access to healthcare services; genetic factors may also play a role. These factors require further investigation.

Stroke, Ahead of Print. BACKGROUND:The VIPS (Vascular Effects of Infection in Pediatric Stroke) II prospective cohort study aimed to better understand published findings that common acute infections, particularly respiratory viruses, can trigger childhood arterial ischemic stroke (AIS). The COVID-19 pandemic developed midway through enrollment, creating an opportunity to assess its impact.METHODS:Twenty-two sites (North America, Australia) prospectively enrolled 205 children (aged 28 days to 18 years) with AIS from December 2016 to January 2022, including 100 cases during the COVID-19 pandemic epoch, defined here as January 2020 to January 2022. To assess background rates of subclinical infection, we enrolled 100 stroke-free well children, including 39 during the pandemic. We measured serum SARS-CoV-2 nucleocapsid total antibodies (present after infection, not vaccination; half-life of 3–6 months). We assessed clinical infection via parental interview.RESULTS:The monthly rate of eligible AIS cases declined from spring through fall 2020, recovering in early 2021 and peaking in the spring. The prepandemic and pandemic cases were similar except pandemic cases had fewer clinical infections in the prior month (17% versus 30%;P=0.02) and more focal cerebral arteriopathy (20% versus 11%;P=0.09). Among pandemic cases, 26 of 100 (26%) had positive antibodies, versus 4 of 39 (10%) of pandemic-era well children (P=0.04). The first SARS-CoV-2 positive case occurred in July 2020. Ten of the 26 (38%) positive cases had a recent infection by parental report, and 7 of those 10 had received a diagnosis of COVID-19. Only 1 had multisystem inflammatory syndrome in children. Median (interquartile range) nucleocapsid IgG total levels were 50.1 S/CO (specimen to calibrator absorbance ratio; 26.9–95.3) in the positive cases and 18.8 (12.0–101) in the positive well children (P=0.33).CONCLUSIONS:The COVID-19 pandemic may have had dual effects on childhood AIS: an indirect protective effect related to public health measures reducing infectious exposure in general, and a deleterious effect as COVID-19 emerged as another respiratory virus that can trigger childhood AIS.

Introduction
New-onset supraventricular arrhythmia (NOSVA) is the most common arrhythmia in patients with septic shock and is associated with haemodynamic alterations and increased mortality rates. With no data available from randomised trials, clinical practice for patient management varies widely. In this setting, rate control or rhythm control could be beneficial in limiting the duration of shock and preventing evolution to multiorgan dysfunction.

Methods and analysis
The Control Atrial Fibrillation in Septic shock (CAFS) study is a binational (French and Belgium), multicentre, parallel-group, open-label, randomised controlled superiority trial to compare the efficacy and safety of three management strategies in patients with NOSVA during septic shock. The expected duration of patient enrolment is 42 months, starting from November 2021. Patients will be randomised to receive either risk control (magnesium and control of risk factors for NOSVA), rate control (risk control and low dose of amiodarone) or rhythm control (risk control and cardioversion using high dose of amiodarone with external electrical shock if NOSVA persists) for 7 days. Patients with a history of SVA, NOSVA lasting more than 48 hours, recent cardiac surgery or a contraindication to amiodarone will not be included. We plan to recruit 240 patients. Patients will be randomised on a 1:1:1 basis and stratified by centre. The primary endpoint is a hierarchical criterion at day 28 including all-cause mortality and the duration of septic shock defined as time from randomisation to successful weaning of vasopressors. Secondary outcomes include: individual components of the primary endpoint; arterial lactate clearance at day 3; efficacy at controlling cardiac rhythm at day 7; proportion of patients free from organ dysfunction at day 7; ventricular arrhythmia, conduction disorders, thrombotic events, major bleeding events and acute hepatitis related to amiodarone at day 28; intensive care unit and hospital lengths of stay at day 28.

Ethics and dissemination
The study has been approved by the French (Comité Sud-Ouest et Outre-Mer II, France, registration number 2019-A02624-53) and Belgian (Comité éthique de l’hôpital Erasme, Belgium, registration number CCB B4062023000179) ethics committees. Patients will be included after obtaining signed informed consent. The results will be submitted for publication in peer-reviewed journals.

Trial registration number
NCT04844801.

Circulation, Ahead of Print. BACKGROUND:TAP-IT (Thoracentesis to Alleviate Cardiac Pleural Effusion–Interventional Trial) investigated the effect of therapeutic thoracentesis in addition to standard medical therapy in patients with acute heart failure and sizeable pleural effusion.METHODS:This multicenter, unblinded, randomized controlled trial, conducted between August 31, 2021, and March 22, 2024, included patients with acute heart failure, left ventricular ejection fraction ≤45%, and non-negligible pleural effusion. Patients with very large effusions (more than two-thirds of the hemithorax) were excluded. Participants were randomly assigned 1:1 to upfront ultrasound-guided pleural pigtail catheter thoracentesis in addition to standard medical therapy or standard medical therapy alone. The primary outcome was days alive out of the hospital over the following 90 days; key secondary outcomes included length of admission and 90-day all-cause mortality. All outcomes were analyzed according to the intention-to-treat principle.RESULTS:A total of 135 patients (median age, 81 years [25th; 75th percentile, 75; 83]; 33% female; median left ventricular ejection fraction, 25% [25th; 75th percentile, 20%; 35%]) were randomized to either thoracentesis (n=68) or standard medical therapy (n=67). The thoracentesis group had a median of 84 days (77; 86) alive out of the hospital over the following 90 days compared with 82 days (73; 86) in the control group (P=0.42). The mortality rate was 13% in both groups, with no difference in survival probability (P=0.90). There were no differences in the duration of the index admission (control group median, 5 days [3; 8]; thoracentesis group median, 5 days [3; 7;P=0.69]). Major complications occurred in 1% of thoracenteses performed during the study period.CONCLUSIONS:For patients with acute heart failure and pleural effusion, a strategy of upfront routine thoracentesis in addition to standard medical therapy did not increase days alive out of the hospital for 90 days, all-cause mortality, or duration of index admission. The current findings lay the groundwork for future research to confirm the results.REGISTRATION:URL:https://www.clinicaltrials.gov; Unique identifier: NCT05017753.

In the Original Investigation, “Low-Value Care at the Actionable Level of Individual Health Systems,” which was published online first on September 27, 2021, and in the November 2021 issue of JAMA Internal Medicine, errors occurred. The calculation for providing antibiotics for upper respiratory infections (URIs) was incorrect. The denominator for this measure was too high, leading to an underestimate of the prevalence of antibiotics for URIs. As explained in a Letter, while this error was present in only 1 of the 41 measures, because the measure for antibiotics for URIs was included in a composite measure of low-value care, the results based on the composite calculation were in error and have been corrected. In addition, the percentage of attributed beneficiaries of non-White race shifted from significant to nonsignificant. Corrections to address these errors do not affect other aspects of the study’s interpretations and conclusions. The following sections of the article have been corrected: Key Points, Abstract, Results and Discussions sections of the main text, Table 2, Figures 1 to 3, eTable 5 in Supplement 1, and the Excel file of eTable 4 in Supplement 2. This article has been corrected.

To the Editor On behalf of my coauthors, I write to explain an error that we detected in our Original Investigation, “Low-Value Care at the Actionable Level of Individual Health Systems,” which was published online first on September 27, 2021, and in the November 2021 issue of JAMA Internal Medicine. This cohort study measured and reported the use of 41 low-value services and a composite measure of 28 services for 556 health systems serving 11.6 million Medicare beneficiaries across the US. We reported that systems varied widely in the provision of low-value care; those with a smaller proportion of primary care physicians, without a major teaching hospital, serving a larger portion of non-White patients, headquartered in the South and West, and serving areas with higher health care spending delivered more low-value care.

Objective
This study aimed to assess the status of infant and young child feeding (IYCF) practices and associated factors among children aged 0–23 months in the low-income regions of Dhaka City, Bangladesh.

Design
A community-based cross-sectional study.

Settings
Low-income regions of Dhaka City, Bangladesh.

Participants
530 children aged 0–23 months and their mothers.

Primary and secondary outcome measures
Prevailing IYCF practices were assessed against the 17 indicators of IYCF recommended by the WHO/UNICEF in 2021. Modified Poisson regression models were built to explore the relation between socio-demographic variables and each of the selected IYCF indicators (early initiation of breastfeeding (EIBF), exclusive breastfeeding (EBF), minimum dietary diversity (MDD), minimum meal frequency (MMF) and minimum acceptable diet (MAD)).

Results
More than two-thirds of the children were reported to follow appropriate breastfeeding practices (EIBF, 70.4% and EBF, 60.9%). Among the complementary feeding indicators, almost half of the children (48.8%) were reported to meet MMF; however, only about 26% of the children reportedly met the MDD with a consequent low prevalence (22.9%) of the composite indicator MAD. More than half (55%) of the children were reported to consume egg and/or flesh food consumption; still, inappropriate dietary practices were observed among 60% had unhealthy food consumption, and 56% had zero vegetable or fruit consumption). Child age was a significant determinant of IYCF practices. The children of mothers with no pregnancy complications exhibited a greater chance of having EIBF (estimate: 1.21, 95% CI: 1.04, 1.42, p=0.02), MDD (Estimate: 1.67, 95% CI: 1.09, 2.55, p=0.02), and MAD (estimate: 1.70, 95% CI: 1.04, 2.77, p=0.03) compared with the children of mothers with pregnancy complications. The children with a mother having secondary or higher education had a higher chance of having MDD (estimate: 1.93, 95% CI: 1.35, 2.76, p=0.003) and MMF (estimate: 1.27, 95% CI: 1.03, 1.56, p=0.02) than the children of mothers having primary or no education. Similarly, children from higher-income households had a higher chance of getting MDD (estimate: 1.57, 95% CI: 1.07, 2.03, p=0.02), and MAD (estimate: 1.73, 95% CI: 1.14, 2.64, p=0.01) compared with children from lower-income households.

Conclusion
IYCF practices among a considerable proportion of children aged 0–23 months in the low-income regions of Dhaka City were found to be suboptimal and predicted by children’s age, maternal education and pregnancy complications, and household income.

Objectives
To describe temporal trends in hospitalisation episodes for venous thromboembolic events (VTEs) in England, and compare hospitalisation rates for pulmonary emboli (PEs) and deep vein thrombosis (DVT).

Methods
Retrospective observational study.

Setting
Secondary care in England, UK, between April 1998 and March 2022.

Participants
Individuals with hospitalisations for VTE recorded in the NHS Digital Hospital Episode Statistics dataset.

Primary and secondary outcomes
The primary outcome was temporal trends in hospitalisation episodes for PE, DVT and VTE overall between 1 April 1998 and 31 March 2022. Secondary outcomes included the proportion of all-cause hospital admissions that were due to VTE; the proportion of all VTE hospitalisations that were recorded as primary admission diagnoses; the male/female split in hospitalisation episodes for VTE; and temporal changes in hospitalisation rates by age.

Results
Between 1998 and 2022, hospitalisations for VTE increased by 62.6%, from 109.5 to 178.1 per 100 000 population. This was driven by a 202% increase in hospitalisations for PE (from 40.4 to 122.2 per 100 000 population). In contrast, hospitalisations for DVT decreased by 19.1% over this period (from 69.1 to 55.9 per 100 000 population). Overall, VTE remained stable as a proportion of all-cause hospital admissions between 1998/1999 and 2019/2020 (0.45% and 0.43%, respectively), before increasing after the onset of the COVID-19 pandemic in England (0.59% in 2020/2021 and 0.51% in 2021/2022).

Conclusion
Hospitalisations for VTE increased markedly in England between 1998 and 2022, driven by large increases in hospitalisations for PE. In contrast, hospitalisations for DVT decreased overall, which may reflect the success of primary care DVT management pathways. Our findings suggest that preventative measures are needed to reduce the incidence of hospitalisations for PE.

Objectives
Using the Korea Health Panel 2021 survey data, we identify factors associated with health literacy (HL) among older adults aged 65 years and older.

Design
A secondary data analysis of the 2021 Korea Health Panel survey.

Setting
Korea Health Panel survey.

Participants
Data were from 3410 older adults greater double equals65 years of age, drawn from the 2016 registration census of the Korea Health Panel 2021 survey, with a stratified selection approach for participants.

Outcome measure
To explore the factors associated with HL within the framework of the Andersen behavioural model, considering predisposing factors (age, gender, region and spouse), enabling factors (National Basic Livelihood Security recipient, education level, economic activity, usual source of care) and need factors (subjective health status, usual activities, depression/anxiety and chronic disease).

Analysis
Stepwise multiple regression analysis was employed to examine the factors associated with HL among the study participants within the framework of the Andersen behavioural model.

Results
Statistically significant associations with HL were found for predisposition factors (age, gender and residential area), enabling factors (National Basic Livelihood Security recipient, educational background and usual source of care) and need factors (subjective health status, usual activities and the presence of chronic diseases). While the National Basic Livelihood Security recipient was significant in model 2 (p=0.011), it became nonsignificant in model 3 after adding need factors (p=0.093). Adding enabling factors to model 1 significantly increased the explanatory power (R2=0.084, p

Objectives
Using the Korea Health Panel 2021 survey data, we identify factors associated with health literacy (HL) among older adults aged 65 years and older.

Design
A secondary data analysis of the 2021 Korea Health Panel survey.

Setting
Korea Health Panel survey.

Participants
Data were from 3410 older adults greater double equals65 years of age, drawn from the 2016 registration census of the Korea Health Panel 2021 survey, with a stratified selection approach for participants.

Outcome measure
To explore the factors associated with HL within the framework of the Andersen behavioural model, considering predisposing factors (age, gender, region and spouse), enabling factors (National Basic Livelihood Security recipient, education level, economic activity, usual source of care) and need factors (subjective health status, usual activities, depression/anxiety and chronic disease).

Analysis
Stepwise multiple regression analysis was employed to examine the factors associated with HL among the study participants within the framework of the Andersen behavioural model.

Results
Statistically significant associations with HL were found for predisposition factors (age, gender and residential area), enabling factors (National Basic Livelihood Security recipient, educational background and usual source of care) and need factors (subjective health status, usual activities and the presence of chronic diseases). While the National Basic Livelihood Security recipient was significant in model 2 (p=0.011), it became nonsignificant in model 3 after adding need factors (p=0.093). Adding enabling factors to model 1 significantly increased the explanatory power (R2=0.084, p

Objectives
The detrimental effects of particulate matter (PM) on human health have been widely corroborated. We aimed to examine the association between outdoor PM and the drug resistance risk among workers and farmers with pulmonary tuberculosis (PTB).

Design
We performed a population-based time-series study using routinely collected meteorological and TB surveillance data.

Setting
We selected Suzhou City, China, as the study area. Data on patients with PTB and meteorological factors were extracted from the National Tuberculosis Online Registration System and the China Meteorological Data Sharing Center.

Participants
This study included 7868 patients with PTB diagnosed from January 2017 to December 2021 in Suzhou.

Methods
The generalised additive model was used to estimate the effects of outdoor PM on the drug resistance risk of TB among workers and farmers who typically work outdoors. Moreover, subgroup analyses were carried out to evaluate the associations in different populations and seasons.

Results
Although there was no significant association between PM with an aerodynamic diameter≤10 µm (PM10) and drug-resistant risk in the overall analysis, subgroup analysis revealed a significant positive association in the winter season. Similarly, PM with an aerodynamic diameter≤2.5 µm (PM2.5) was significantly associated with drug resistance risk among males with a lag of 0–3 days, people ≤60 years with a lag of 0–7 days and in the winter season with a lag of 0–7 days, 0–15 days, 0–90 days or 0–180 days.

Conclusions
Outdoor PM10 and PM2.5 were positively related to the drug resistance risk of workers and farmers with PTB. Reducing ambient PM pollution might reduce the burden of TB. Further research is required to verify the association through in vitro experiments and extensive cohort studies.

Introduction
Vasopressor support is often preferred as an efficient and convenient way to raise the blood pressure during surgery and intensive care therapy. However, the optimal vasopressor for ensuring organ blood flow and tissue oxygen delivery during surgery remains undetermined. This study aims to assess the impact of norepinephrine versus phenylephrine on cerebral and non-cerebral organ perfusion and oxygenation during anaesthesia in neurosurgical patients with brain tumours. The study also explores the impact of the vasopressor agents on the distribution of cardiac output between various organs.

Methods and analysis
This is an investigator-initiated, double-blinded, randomised clinical trial including 32 patients scheduled for supratentorial brain tumour surgery. The patients are randomised to receive a phenylephrine or norepinephrine infusion during preoperative positron emission tomography (PET) examinations and the following neurosurgical procedure. PET measurements of blood flow and oxygen metabolism in the brain and other organs are performed on the awake subject during anaesthesia, following a 10% and 20% gradual increase in blood pressure from the baseline value. The primary endpoint is the between-group difference in cerebral blood flow. Secondary endpoints include detection of ischaemic brain lesions possibly associated with vasopressor treatment, changes in cerebral oxygen metabolism, non-cerebral organ blood flow and oxygen metabolism, cardiac output, regional cerebral oxygen saturation, autoregulation and distribution of cardiac output between organs.

Ethics and dissemination
This study was approved by the Danish National Medical Ethics Committee (20 May 2022; 2203674). Results will be disseminated via peer-reviewed publication and presentation at international conferences.

Trial registration number
EudraCT no: 2021-006168-26. ClinicalTrials.gov: NCT06083948.

Objective
To determine if there is research waste in controlled trials of exercise therapies compared with usual care/no treatment for adults with chronic non-specific lower back pain.

Design and data sources
Secondary analysis of previously published systematic review (Cochrane review).

Eligibility criteria
Randomised controlled trials comparing exercise treatments for chronic low back pain to usual care/no treatment eligible for inclusion in the 2021 Cochrane review of exercise interventions for chronic low back pain.

Data extraction and synthesis
All data were taken from the 2021 Cochrane review of exercise therapy for chronic lower back pain and the UK BEAM trial. We did trial-sequential meta-analysis and cumulative meta-analyses, exploring changes in effect estimates over time and by trial size.

Results
Respective superiority boundaries for pain and disability were crossed in 2004 after four and five trials (n=358/415) were published. A further 43 trials with 2626 participants were included in the Cochrane review. In 2004, the mean effect sizes for pain and disability were –12.85 (95% CI –24.89 to –0.81) and –6.67 (95% CI –11.27 to 3.36), respectively; similar to those reported by Cochrane in 2021. Including small trials substantially affected effect size estimates. When the 33 and 36 trials, respectively, with fewer than 70 participants are excluded, the limits of the 95% CIs for effect size estimates exclude the clinically important differences ((pain; –8.8 (95% CI –11.38 to –5.63): disability –4.27 (95% CI –6.12 to –2.24).

Conclusions
It may be difficult to justify any further trials comparing exercise interventions to usual care/no treatment for chronic low back pain. The inclusion of small studies in meta-analyses has produced biased results in previous meta-analyses. Exercise treatments might not have a clinically important effect on people with chronic low back pain.