Dysphagia (difficulty swallowing) and airway obstruction can be caused by a problem known as Diffuse Idiopathic Skeletal Hyperostosis or DISH. Until now, it was believed that DISH was a rare cause of compression of the esophagus and trachea. But thanks to the efforts of researchers in the Netherlands, we have found out that this condition is on the rise around the world.
Diffuse Idiopathic Skeletal Hyperostosis (DISH) causes ligaments along the front and back of the vertebrae (spine) to turn into bone. It is also known as Forestier’s disease, after the name of the physician who recognized it. DISH more commonly affects older males.
It is usually associated with stiffness and back pain, but often it causes no signs or symptoms. When the cervical spine (neck) is affected, other symptoms may occur such as stiff neck with loss of motion, difficulty swallowing, painful swallowing, choking, and snoring.
The condition is most often confirmed by X-ray when there are at least four vertebral segments in a row ossified (hardened into bone). Other imaging tests used in the differential diagnosis include barium swallow radiography, CT scan, laryngoscopy, and MRI.
By performing a literature review called a systematic review, the authors of this article found 95 individual patient case reports and another 23 case series. A total of 204 people have been reported with this condition of difficulty swallowing, talking, and/or breathing because of the effects of DISH in the cervical spine (neck) and throat area.
The most significant finding of this systematic review is the fact that between 1980 and 2009, the number of cases reported has continued to rise. What’s behind this increase in neck and throat problems from DISH? Scientists aren’t sure yet but they do have some ideas.
First, it has been observed that adults who develop DISH are more likely to also have type 2 diabetes and be obese. Both of those conditions are abnormalities in metabolism. Since the formation of bone depends on growth factors such as insulin-like Growth Factor, it’s possible there is an underlying metabolic component to the disease. With more and more people who are obese and developing diabetes, it’s expected that the number of individuals affected by DISH will also increase in the coming years.
Second, with improved imaging technology, it’s possible that physicians are able to detect the condition more readily than in the past. This suggests that perhaps the incidence isn’t rising as much as the diagnosis is being accurately made more often. And the fact that many people have DISH and don’t know it (they have no symptoms) has kept some people from being diagnosed early on or at all.
Third, an association between heart disease and DISH may be a new discovery made by this study. By looking at these 204 cases and examining reported comorbidities (other medical problems people with DISH have), they found a higher rate of high blood pressure and coronary artery disease than previously appreciated.
The authors concluded from their study that dysphagia and airway obstruction as a result of DISH are not as rare as was once thought. The problem is not confined to one group of people or country either. Although Japanese people develop ossification of the posterior ligament of the spine more often than other groups, the case series came from around the world.
It is believed that there is a “gross underestimation” (author’s words) of the real number of cases of this problem. They further stated that the DISH condition of the cervical spine is not a “radiologic oddity” as some radiologists claim, but rather something that causes real problems. The changes observed on X-rays just are’t recognized for what they really are.
And finally, once radiologists are trained to recognize DISH when they see it, the authors believe the number of reported cases will increase even more. Physicians should get ready to see a steady increase in the number of cases of DISH. Likewise, the number of individuals with DISH affecting the neck will also increase as people live longer and develop more heart conditions, and metabolic problems such as insulin resistance, obesity, and diabetes.