Who caused stroke

The article:

professional misrepresentation

From Emergency Medicine Journal

Vertebral artery dissection and cerebellar infarction following chiropractic manipulation.

•Chen WL, Chern CH, Wu YL, Lee CH.

Department of Emergency Medicine, Cathay General Hospital, Republic of China. weilung.chen@msa.hinet.net

The article states:

“Vertebral artery dissection (VAD) associated with chiropractic cervical manipulation is a rare but potentially disabling condition. In this report, we present a young patient manifesting with repeated vertigo. Owing to the initial misdiagnosis, the patient later developed cerebellar stroke with inability to stand or walk.

Vertigo and disequilibrium are the usual presenting symptoms of this condition, which can result from inner ear or vestibular nerve dysfunction, vertebrobasilar insufficiency, and even lethal cerebellar infarction or haemorrhage; these last two, although rarely seen in young adults, can be caused by traumatic or spontaneous arterial injury, including injury secondary to chiropractic cervical manipulation. A number of cases of VAD associated with chiropractic cervical manipulation have been reported, but rarely in the emergency medicine literature. We present a case of this rare occurrence, and discuss the diagnostic pitfalls.”

The Response:

setting the record straight

Published by Emergency Medicine Journal

In a letter to the editor, academic Dr D Liu (from Department of Biochemistry/Physiology, Canadian Memorial Chiropractic College) clarifies: (emphasis added)

“On communication with Dr Chen, it was clarified that this manipulation was performed by an individual who graduated from a college associated with ‘Chinese herbs’. This individual did not graduate from an accredited chiropractic college, nor is he licensed to practise chiropractic by any other means. ... Similar to the fact that only qualified surgeons can perform surgeries, only qualified chiropractors can perform chiropractic manipulation.

In addition, the authors report that chiropractors perform adjustments without acknowledging relevant risks. This statement is also false. Chiropractors are duly trained to identify risk factors for spinal manipulation and, in many jurisdictions, are required to obtain informed consent.

I understand that the intent of this article was to convey to other emergency ward doctors the diagnostic pitfalls associated with the presentation of cerebellar infarction. However, it is important that this issue be clarified because the use of the term "chiropractic" was misleading to the public and potentially harmful to the profession.”

MAJOR STUDY concludes:
NO MORE RISK OF STROKE AFTER GOING TO THE MEDICAL DOCTOR
SPINE Volume 33, Number 4S, pp S176 –S183 ©2008, Lippincott Williams & Wilkins

Risk of Vertebrobasilar Stroke and Chiropractic Care
Results of a Population-Based Case-Control and Case-Crossover Study
J. David Cassidy, DC, PhD, DrMedSc,*†‡ Eleanor Boyle, PhD,* Pierre Coˆ te´ , DC, PhD,*†‡§
Yaohua He, MD, PhD,* Sheilah Hogg-Johnson, PhD,†§ Frank L. Silver, MD, FRCPC,¶􏰀
and Susan J. Bondy, PhD†

Study Design. Population-based, case-control and
case-crossover study.

Objective. To investigate associations between chiro-
practic 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 head-
ache 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 seek-
ing care before their stroke. We found no evidence of
excess risk of VBA stroke associated chiropractic care
compared to primary care.

Spine 2008;33:S176 –S183

From the *Centre of Research Expertise for Improved Disability
Outcomes (CREIDO), University Health Network Rehabilitation
Solutions, Toronto Western Hospital, and the Division of Heath
Care and Outcomes Research, Toronto Western Research Institute,
Toronto, ON, Canada; †Department of Public Health Sciences,
Management and Evaluation, University of Toronto, Toronto, ON,
Canada; ‡Department of Health Policy, Management and Evalua-
tion, University of Toronto, Toronto, ON, Canada; §Institute for
Work & Health, Toronto, ON, Canada; ¶University Health Net-
work Stroke Program, Toronto Western Hospital, Toronto, ON,
Canada; and 􏰀Division of Neurology, Department of Medicine, Fac-
ulty of Medicine, University of Toronto, Toronto, ON, Canada.
Supported by Ontario Ministry of Health and Long-term Care. P.C. is
supported by the Canadian Institute of Health Research through a New
Investigator Award. S.H.-J. is supported by the Institute for Work &
Health and the Workplace Safety and Insurance Board of Ontario.
The opinions, results, and conclusions are those of the authors and no
endorsement by the Ministry is intended or should be inferred.
The manuscript submitted does not contain information about medical
device(s)/drug(s).
University Health Network Research Ethics Board Approval number
05-0533-AE.
Address correspondence and reprint requests to J. David Cassidy, DC,
PhD, DrMedSc, Toronto Western Hospital, Fell 4-114, 399 Bathurst
Street, Toronto, ON, Canada M5T 2S8; E-mail: dcassidy@uhnresearch.ca