Eleanor Boyle

Risk of vertebrobasilar stroke and chiropractic care: results of a population-based case-control and case-crossover study.

Study Design. Population-based, case-control and case-crossover study. Objective. To investigate associations between chiropractic visits and vertebrobasilar artery (VBA) stroke and to contrast this with primary care physician (PCP) visits and VBA stroke. Summary of Background Data. Chiropractic care is popular for neck pain and headache, but may increase the risk for VBA dissection and stroke. Neck pain and headache are common symptoms of VBA dissection, which commonly precedes VBA stroke. Methods. Cases included eligible incident VBA strokes admitted to Ontario hospitals from April 1, 1993 to March 31, 2002. Four controls were age and gender matched to each case. Case and control exposures to chiropractors and PCPs were determined from health billing records in the year before the stroke date. In the case-crossover analysis, cases acted as their own controls. Results. There were 818 VBA strokes hospitalized in a population of more than 100 million person-years. In those aged <45 years, cases were about three times more likely to see a chiropractor or a PCP before their stroke than controls. Results were similar in the case control and case crossover analyses. There was no increased association between chiropractic visits and VBA stroke in those older than 45 years. Positive associations were found between PCP visits and VBA stroke in all age groups. Practitioner visits billed for headache and neck complaints were highly associated with subsequent VBA stroke. Conclusion. VBA stroke is a very rare event in the population. The increased risks of VBA stroke associated with chiropractic and PCP visits is likely due to patients with headache and neck pain from VBA dissection seeking care before their stroke. We found no evidence of excess risk of VBA stroke associated chiropractic care compared to primary care.

Systematic review of prognosis after mild traumatic brain injury in the military: results of the International Collaboration on Mild Traumatic Brain Injury Prognosis

OBJECTIVE The World Health Organization Collaborating Centre Task Force on Mild Traumatic Brain Injury (MTBI) published its findings on the prognosis of MTBI in 2004. This is an update of that review with a focus on deployed military personnel. DATA SOURCES Relevant literature published between January 2001 and February 2012 listed in MEDLINE and 4 other databases. STUDY SELECTION Controlled trials and cohort and case-control studies were selected according to predefined criteria. After 77,914 titles and abstracts were screened, 13 articles were rated eligible for this review and 3 (23%) with a low risk of bias were accepted. Two independent reviewers critically appraised eligible studies using a modification of the Scottish Intercollegiate Guidelines Network criteria. DATA EXTRACTION The reviewers independently extracted data from eligible studies and produced evidence tables. DATA SYNTHESIS The evidence was synthesized qualitatively and presented in evidence tables. Our findings are based on 3 studies of U.S. military personnel who were deployed in Iraq or Afghanistan. We found that military personnel with MTBI report posttraumatic stress disorder and postconcussive symptoms. In addition, reporting of postconcussive symptoms differed on the basis of levels of combat stress the individuals experienced. The evidence suggests a slight decline in neurocognitive function after MTBI, but this decline was in the normal range of brain functioning. CONCLUSIONS We found limited evidence that combat stress, posttraumatic stress disorder, and postconcussive symptoms affect recovery and prognosis of MTBI in military personnel. Additional high-quality research is needed to fully assess the prognosis of MTBI in military personnel.

Population-Based, Inception Cohort Study of the Incidence, Course, and Prognosis of Mild Traumatic Brain Injury After Motor Vehicle Collisions

OBJECTIVE To determine the incidence, course, and prognosis of adult mild traumatic brain injury (MTBI) caused by motor vehicle collisions. DESIGN Prospective, population-based, inception cohort study. SETTING The province of Saskatchewan, Canada, with a population of about 1,000,000 inhabitants. PARTICIPANTS All adults (N=1716) incurring an MTBI in a motor vehicle collision between November 1997 and December 1999 in Saskatchewan. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Age- and sex-stratified incidence rates, time to self-reported recovery, and prognostic factors over a 1-year follow-up. RESULTS Of 7170 adults injured in a motor vehicle collision over the 2-year inception period, 1716 (24%) met our cohort definition of MTBI. There were more women affected (53%), and MTBI was most common in the 18- to 23-year-old group. Most were not hospitalized (73%), but 28% reported loss of consciousness and 23% reported posttraumatic amnesia. The annual incidence of MTBI per 100,000 adults was 106.1 (95% confidence interval [CI], 98.9-113.6) in the first year and 118.3 (95% CI, 110.8-126.3) in the second year of the study. The 1-year follow-up rate was 84%. The median time to recovery was 100 days (95% CI, 97-103), and about 23% reported not having recovered by 1 year. Factors associated with delayed recovery included being older than 50 years, having less than a high school education, having poor expectations for recovery, having depressive symptoms, having arm numbness, having hearing problems, having headaches, having low back pain, and having thoracic back pain. Loss of consciousness and posttraumatic amnesia were not associated with recovery. CONCLUSIONS MTBI affects almost a quarter of persons reporting an injury after a traffic collision. The median time to recovery is 100 days, but 23% have still not recovered by 1 year. A mix of biopsychosocial factors is associated with recovery, including a strong effect of poor expectations for recovery.

Examining Vertebrobasilar Artery Stroke in Two Canadian Provinces

Study Design. Ecological study. Objectives. To determine the annual incidence of hospitalized vertebrobasilar artery (VBA) stroke and chiropractic utilization in Saskatchewan and Ontario between 1993 and 2004. To determine whether at an ecological level, the incidence of VBA stroke parallels the incidence of chiropractic utilization. Summary of Background Data. Little is known about the incidence and time trends of VBA stroke diagnoses in the population. Chiropractic manipulation to the neck is believed to be a risk factor for VBA stroke. No study has yet found an association between chiropractic utilization and VBA diagnoses at the population level. Methods. All hospitalizations with discharge diagnoses of VBA stroke were extracted from administrative databases for Saskatchewan and Ontario. We included incident cases that were diagnosed between January 1993 and December 2004 for Saskatchewan and from April 1993 to March 2002 for Ontario. VBA cases that had previously been hospitalized for any stroke or transient ischemic attack (TIA) were excluded. Chiropractic utilization was measured using billing data from Saskatchewan Health and Ontario Health Insurance Plan. Denominators were derived from Statistics Canada’s annual population estimates. Results. The incidence rate of VBA stroke was 0.855 per 100,000 person-years for Saskatchewan and 0.750 per 100,000 person-years for Ontario. The annual incidence rate spiked dramatically with a 360% increase for Saskatchewan in 2000. There was a 38% increase for the 2000 incidence rate in Ontario. The rate of chiropractic utilization did not increase significantly during the study period. Conclusion. In Saskatchewan, we observed a dramatic increase in the incidence rate in 2000 and there was a corresponding relatively small increase in chiropractic utilization. In Ontario, there was a small increase in the incidence rate; however, chiropractic utilization decreased. At the ecological level, the increase in VBA stroke does not seem to be associated with an increase in the rate of chiropractic utilization.

Mild Traumatic Brain Injury After Motor Vehicle Collisions: What Are the Symptoms and Who Treats Them? A Population-Based 1-Year Inception Cohort Study

OBJECTIVE To describe the 1-year course of symptoms following mild traumatic brain injury (MTBI) sustained in a motor vehicle collision as well as patterns of care-seeking. DESIGN One-year follow-up of a population-based inception cohort. SETTING The province of Saskatchewan, Canada, with a population of about 1,000,000 inhabitants. PARTICIPANTS Persons (N=1716) sustaining an MTBI during a car collision between November 1997 and December 1999. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES We report the prevalence of sleep disturbances, tiredness, dizziness, forgetfulness, vision problems, hearing problems, headache, neck pain, mid back pain, and low back pain at 6 weeks and 3, 6, 9, and 12 months postcollision. At the same time points, we report self-reported care-seeking from registered health care professionals. RESULTS A total of 1716 adults suffered MTBI after a motor vehicle collision over the 2-year inception period. Six weeks after the collision, 75% reported having more than 3 symptoms and 30% had clinically significant pain in more than 3 body sites. Over time, the prevalence of symptoms and pain decreased but they were still common after 1 year. Almost all participants sought care for their symptoms at all time points, most commonly from a physician. Care-seeking from physiotherapists, chiropractors, and massage therapists was also very common, and most participants sought care from 2 or 3 providers at all follow-up points. CONCLUSIONS Up to 1 year after sustaining an MTBI during a motor vehicle collision, multiple symptoms and pain in several anatomical sites are common. Care-seeking from multiple providers continues throughout the first year postinjury.

Are Modic changes prognostic for recovery in a cohort of patients with non-specific low back pain?

BackgroundThere is evidence for an association between Modic type 1 and pain in patients with low back pain (LBP), but little knowledge about its effect on clinical outcomes.Purpose(1) To assess the prevalence of Modic changes, (2) to determine if Modic changes influence the clinical course of LBP, and (3) to identify prognostic factors for recovery.Study design/settingProspective clinical cohort study, with a 1-year follow-up. The treatment consisted of brief intervention and instruction in stretching.Patient’s sampleTwo hundred and sixty-nine patients with chronic low back pain.Outcome measuresSocio-demographic variables, education, profession, self-reported measures, degenerative changes on MRI.MethodsLinear growth model and Cox regression analysis.ResultsFive percent had a normal MRI, 14 and 50% had Modic 1 and Modic 2 changes. Modic changes were not significant covariates for the clinical course of pain, function or fear avoidance beliefs. Education was a strong prognostic factor for recovery.ConclusionsModic changes did not influence the clinical course of back pain and were not prognostic factors for recovery. Education was strongly associated with recovery.

A Population-Based Case-Series of Ontario Patients Who Develop a Vertebrobasilar Artery Stroke After Seeing a Chiropractor

PURPOSE The current evidence suggests that association between chiropractic care and vertebrobasilar artery (VBA) stroke is not causal. Rather, recent epidemiological studies suggest that it is coincidental and reflects the natural history of the disorder. Because neck pain and headaches are symptoms that commonly precede the onset of a VBA stroke, these patients might seek chiropractic care while their stroke is in evolution. However, very little is known about the characteristics of these patients. In fact, only small clinical case series and physician surveys have described the characteristics of chiropractic patients who later develop a VBA stroke. To date, no population-based study has described this group of patients. Therefore, the objective of our study is to describe the characteristics of Ontario VBA stroke patients who consulted a chiropractor within the year before their stroke. METHODS We conducted a population-based case series using administrative health care records of all Ontario residents hospitalized with VBA stroke between April 1, 1993, and March 31, 2002. Three databases were deterministically linked to extract the relevant information. We describe the demographic, health care utilization, and comorbidities of VBA patients. RESULTS Ninety-three VBA stroke cases consulted a chiropractor during the year before their stroke. The mean age was 57.6 years (SD, 16.1), and 50% were female. Most cases had consulted a medical doctor during the year before their stroke, and 75.3% of patients had at least one cerebrovascular comorbidity. The 3 most common comorbidities were neck pain and headache (prevalence, 66.7%; 95% confidence interval [CI], 57.0%-76.3%), diseases of the circulatory system (prevalence, 63.4%; 95% CI, 54.8%-74.2%), and diseases of the nervous system and sense organs (prevalence, 47.3%; 95% CI, 38.7%-58.1%). CONCLUSIONS Our population-based analysis suggests that VBA stroke patients who consulted a chiropractor the year before their stroke are older than previously documented in clinical case series. We did not find that women were more commonly affected than men. Moreover, we found that most patients had at least one cardio- or cerebrovascular comorbidity. Our analysis suggests that relying on case series or surveys of health care professionals may provide a biased view of who develops a VBA stroke.

Identifying the Best Treatment Among Common Nonsurgical Neck Pain Treatments : A Decision Analysis

Study Design. Decision analysis. Objective. To identify the best treatment for nonspecific neck pain. Summary of Background Data. In Canada and the United States, the most commonly prescribed neck pain treatments are nonsteroidal anti-inflammatory drugs (NSAIDs), exercise, and manual therapy. Deciding which treatment is best is difficult because of the trade-offs between beneficial and harmful effects, and because of the uncertainty of these effects. Methods. (Quality-adjusted) life expectancy associated with standard NSAIDs, Cox-2 NSAIDs, exercise, mobilization, and manipulation were compared in a decision-analytic model. Estimates of the course of neck pain, background risk of adverse events in the general population, treatment effectiveness and risk, and patient-preferences were input into the model. Assuming equal effectiveness, we conducted a baseline analysis using risk of harm only. We assessed the stability of the baseline results by conducting a second analysis that incorporated effectiveness data from a high-quality randomized trial. Results. There were no important differences across treatments. The difference between the highest and lowest ranked treatments predicted by the baseline model was 4.5 days of life expectancy and 3.4 quality-adjusted life-days. The difference between the highest and lowest ranked treatments predicted by the second model was 7.3 quality-adjusted life-days. Conclusion. When the objective is to maximize life expectancy and quality-adjusted life expectancy, none of the treatments in our analysis were clearly superior.

Does training frequency and supervision affect compliance, performance and muscular health? A cluster randomized controlled trial

The aim was to determine the effect of one weekly hour of specific strength training within working hours, performed with the same total training volume but with different training frequencies and durations, or with different levels of supervision, on compliance, muscle health and performance, behavior and work performance. In total, 573 office workers were cluster-randomized to: 1 WS: one 60-min supervised session/week, 3 WS: three 20-min supervised sessions/week, 9 WS: nine 7-min supervised sessions/week, 3 MS: three 20-min sessions/week with minimal supervision, or REF: a reference group without training. Outcomes were diary-based compliance, total training volume, muscle performance and questionnaire-based health, behavior and work performance. Comparisons were made among the WS training groups and between 3 WS and 3 MS. If no difference, training groups were collapsed (TG) and compared with REF. Results demonstrated similar degrees of compliance, mean(range) of 39(33-44)%, and total training volume, 13.266(11.977-15.096)kg. Musculoskeletal pain in neck and shoulders were reduced with approx. 50% in TG, which was significant compared with REF. Only the training groups improved significantly their muscle strength 8(4-13)% and endurance 27(12-37)%, both being significant compared with REF. No change in workability, productivity or self-rated health was demonstrated. Secondary analysis showed exercise self-efficacy to be a significant predictor of compliance. Regardless of training schedule and supervision, similar degrees of compliance were shown together with reduced musculoskeletal pain and improved muscle performance. These findings provide evidence that a great degree of flexibility is legitimate for companies in planning future implementation of physical exercise programs at the workplace. ClinicalTrials.gov, number NCT01027390.

Prognosis of patients with whiplash-associated disorders consulting physiotherapy: development of a predictive model for recovery

BackgroundPatients with whiplash-associated disorders (WAD) have a generally favourable prognosis, yet some develop longstanding pain and disability. Predicting who will recover from WAD shortly after a traffic collision is very challenging for health care providers such as physical therapists. Therefore, we aimed to develop a prediction model for the recovery of WAD in a cohort of patients who consulted physical therapists within six weeks after the injury.MethodsOur cohort included 680 adult patients with WAD who were injured in Saskatchewan, Canada, between 1997 and 1999. All patients had consulted a physical therapist as a result of the injury. Baseline prognostic factors were collected from an injury questionnaire administered by Saskatchewan Government Insurance. The outcome, global self-perceived recovery, was assessed by telephone interviews six weeks, three and six months later. Twenty-five possible baseline prognostic factors were considered in the analyses. A prediction model was built using Cox regression. The predictive ability of the model was estimated with concordance statistics (c-index). Internal validity was checked using bootstrapping.ResultsOur final prediction model included: age, number of days to reporting the collision, neck pain intensity, low back pain intensity, pain other than neck and back pain, headache before collision and recovery expectations. The model had an acceptable level of predictive ability with a c-index of 0.68 (95% CI: 0.65, 0.71). Internal validation showed that our model was robust and had a good fit.ConclusionsWe developed a model predicting recovery from WAD, in a cohort of patients who consulted physical therapists. Our model has adequate predictive ability. However, to be fully incorporated in clinical practice the model needs to be validated in other populations and tested in clinical settings.