Common Causes of Dizziness

AgreeI Respectfully Disagree with the Abstract

(but I agree and am impressed by the article)

A recent article titled Causes of Persistent Dizziness in Elderly Patients in Primary Care (Maarsingh et al. 2010) is a welcome addition to the literature. Dizziness and vertigo are bothersome and common complaints, particularly in the elderly population. There has been much written and discussed regarding the appropriate management of these patients. It would only make sense that if we knew what condition was most likely to be the cause of such complaints, we could alter our diagnostic and treatment strategies accordingly.

One thing we need to be careful about in drawing conclusions from any etiology studies is something called “research bias.” Here is a blurb regarding research bias from my last book:

Etiology

“Several studies have been performed to determine the probable cause of dizziness in a selected group of individuals. These studies differ both in the group studied (typically by age) and the group completing the study (primary care versus specialty dizziness clinic). It would seem that data obtained by specialty clinics would be influenced by the fact that if a patient were referred to an otology- or neurology-based clinic for evaluation, someone (either the patient or the primary care physician) has already suspected that the cause of dizziness may be otologic or neurologic in nature.”

A second caveat to any study regarding etiology is that you will most likely find that the pathologies you are looking for seem to show up more often than pathologies that you are not looking for. This seems obvious, but I caution readers to view the results of the above linked study from this perspective. The study, contrary to many previous studies finding vestibular disorders as the most common cause, found cardiovascular pathology to be the most common cause of persistent dizziness in a Primary Care setting.

Hold on just a minute. Let’s look closer at how they evaluated these patients.

To determine if a complaint was from vestibular function, they performed 1. Otoscopy, 2. Audiometry, and 3. a Dix-Hallpike exam. But, what about the rest of the exams available to us that are sensitive in detecting vestibular dysfunction? I suspect some cases of vestibular dysfunction may have been missed.

To the authors’ credit, they are aware and acknowledged potential for research bias, and also acknowledged the vagueness of the term “dizzy.” I have discussed the problems with using the catch-all term of dizziness in previous blogs. In the Maarsingh study, presyncope was the most common specific complaint.

This is a situation where I think the abstract is misleading, but the complete article included the necessary qualifiers. My words of caution, “Please read the entire article and don’t form any conclusions based on the abstract alone.”

Photo courtesy of http://truth459.blogspot.com/2013/01/agree-to-disagree-not-101-blog.html

About Alan Desmond

Dr. Alan Desmond is the director of the Balance Disorders Program at Wake Forest Baptist Health Center, and holds an adjunct assistant professor faculty position at the Wake Forest School of Medicine. In 2015, he received the Presidents Award from the American Academy of Audiology.