The Prevalence and Nature of Eating and Swallowing Problems in Adults with Fibromyalgia: A Systematic Review.

Only six studies were found and they differed in design, sample and methods, so results could be combined for dysphagia and reflux only; most outcomes have no pooled estimate at all. The pooled dysphagia figure of 51.9% rests on two studies, and the range it could plausibly take (25.6% to 77.2%) is wide, so the real rate in your clinic could be much lower or much higher. Half the studies were rated moderate quality, one was poor, and small samples and unclear sample size calculations were common. Some of the 100% figures come from a single case report of one patient and cannot tell you how common those problems are. Most studies did not record which medications patients were taking, and many fibromyalgia drugs can cause dry mouth, drowsiness and gut upset that may themselves cause eating and swallowing problems. Fibromyalgia often co-exists with conditions that cause swallowing problems, such as stroke or multiple sclerosis, so it is unclear how much the fibromyalgia itself adds. Fibromyalgia diagnostic criteria have changed over time and the search may have missed studies using other criteria; publication bias could also mean fewer studies were found than exist.

The paper names the University of Dublin, Trinity College as its funder. The supplied text gives no further funding or competing-interest statement, so nothing more can be said about who had a role in designing, running or writing up the work.

Do not treat 51.9% as an established rate of swallowing problems in fibromyalgia. It is pooled from only two studies, and the analysis allows for a real figure anywhere between 25.6% and 77.2%. The 100% figures for painful swallowing, burning mouth and altered taste come from a single case report of one patient, not from a patient group.