Fibromyalgia Diagnosis Doubles Risk Of Serious Traffic Crashes: ICES Study

Fibromyalgia Diagnosis Doubles Risk Of Serious Traffic Crashes: ICES Study

Being diagnosed with fibromyalgia also indicates a doubling of the risk of a person becoming involved in a serious traffic crash, and that elevated statistical risk continues for years after the initial diagnosis, according to a new study by researchers at the Toronto based Institute for Clinical Evaluative Sciences (ICES) to be published The Journal of Rheumatology.

Fibromyalgia (FM) is a common but not-well-understood disorder of unknown etiology, and characterized by widespread pain, that is believed to affect more than 200,000 Canadian adults. Estimates of the number of Americans affected vary substantially. The National Institutes of Health says some 5 million Americans 18 or older are afflicted with the syndrome, while others maintain it’s more like 8 to 12 million.

Whichever the correct metric is, the numbers of North Americans suffering from this condition that disrupts nerve function and leads to chronic pain are substantial. Fibromyalgia is associated with widespread fluctuating symptoms including muscle pain, fatigue, insomnia, and joint stiffness that can be treated by medications, lifestyle changes and stress management.

In their paper, the ICES researchers observe that past research has shown that fibromyalgia is sometimes a consequence of a past motor vehicle crash; however, this is the first study to investigate whether fibromyalgia could also lead to a future motor vehicle crash.

“We found the absolute risk of a serious motor vehicle crash for adults diagnosed with fibromyalgia approached the rate observed among other patients diagnosed with alcoholism,” says Dr. Donald Redelmeier, senior scientist at ICES and senior author of the study, now published online ahead of print in The Journal of Rheumatology, and slated for print publication next week. Dr. Redelmeier also holds the Canada Research Chair in Medical Decision Sciences; is a professor of medicine at the University of Toronto; director of clinical epidemiology at Sunnybrook Health Sciences Centre; and staff physician in the Division of General Internal Medicine at Sunnybrook Hospital.

The researchers estimate that increased absolute risk of traffic crashes equates to about a seven percent annual chance of a traffic crash of some severity involving drivers with fibromyalgia. Dr. Redelmeier cautions that this does not necessarily mean fibromyalgia patients are at-fault for the traffic crash; and it’s quite possible, that fibromyalgia may impair a driver’s ability to avoid involvement in a crash caused by someone else.

However, the coauthors note that motor vehicle crashes can be serious for patients with chronic medical conditions, and the significant consequences that obtain provide a rationale for health prevention measures, including warnings by physicians to patients regarding safe driving. They note that most highway crashes can be avoided by heeding standard traffic safety advice such as respecting speed limits, actually stopping at stop signs, and avoiding the many driver distractions that have increased exponentially in our era of cell phones, texting, music streaming, and the burgeoning ubiquity of in-car electronic infotainment and navigation systems.

Noting that motor vehicle crashes are a widespread contributor to mortality and morbidity, and sometimes are related to medically unfit motorists. the ICES researchers conducted a population-based, self-matched longitudinal cohort analysis of 137,631 adults diagnosed with fibromyalgia between April 1, 2006 and March 31, 2012 in Ontario, of whom 738 had been involved in another crash in the first year following diagnosis. They tested whether patients diagnosed with fibromyalgia have an increased risk of a subsequent serious motor vehicle crash. Individuals younger than 18 years, living outside Ontario, lacking valid identifiers, or having only a single visit for the diagnosis were excluded from the study.

The scientists found that the crash rate was more than twice the population norm for both those with a new or a persistent fibromyalgia diagnosis. The researchers defined a serious motor vehicle crash as incidents severe enough to send the driver to hospital for an emergency department visit.

As Dr.Redelmeier noted, the increased risk included patients with diverse characteristics, approached the rate observed among other patients diagnosed with alcoholism, but the risk was mitigated among those who received dedicated FM care or a physician warning for driving safety, and the coauthors conclude that based on their findings a diagnosis of FM is associated with an increased risk of a subsequent motor vehicle crash that might justify medical interventions for traffic safety.

“Our study shows that a diagnosis of fibromyalgia identifies individuals at ongoing risk of a serious traffic crash who might benefit from specific medical treatment to mitigate this risk,” observes Dr. Redelmeier, who is also a staff physician at Sunnybrook Health Sciences Centre and a professor of medicine at the University of Toronto.

The researchers stress that their data do not prove that fibromyalgia caused the crashes, because fibromyalgia patients may differ in multiple ways from the population norm, with potential differences that include comorbidities, use of psychotropic drugs, and amounts of daily driving. They also suggest that fibromyalgia might also impair a person’s ability to avoid a crash or impede a person’s ability to recover afterward.

Entitled “Fibromyalgia and the risk of a subsequent motor vehicle crash)( doi:10.3899/jrheum.141315), the Open Access paper is currently available online in The Journal of Rheumatology and will be published in print next week. It is coauthored by D.A. Redelmeier, MD, FRCPC, MSHSR, FACP of the University of Toronto’s Department of Medicine, the Evaluative Clinical Sciences Platform at Sunnybrook Research Institute in Toronto, the Institute for Clinical Evaluative Sciences in Ontario, and the Center for Leading Injury Prevention Practice Education and Research, Toronto; J.D. Zung, BSc, of the Department of Medicine, University of Toronto, and the Evaluative Clinical Sciences Platform, Sunnybrook Research Institute, and the Institute for Clinical Evaluative Sciences in Ontario; D. Thiruchelvam, MSc, of the Evaluative Clinical Sciences Platform at Sunnybrook Research Institute; and R.J. Tibshirani, PhD, of the Department of Statistics at Stanford University in Stanford, California, USA.

The research was supported by a Canada Research Chair in Medical Decision Sciences, the Canadian Institutes of Health Research, the Physicians Services Incorporated Foundation, and a D+H SRI Summer Student award.

The full text of this Open Access article is available in PDF format at:

Institute for Clinical Evaluative Sciences (ICES)
The Journal of Rheumatology

Image Credit:
Institute for Clinical Evaluative Sciences (ICES)