Fibromyalgia - A Link to Sleep Problems?

Summarized by Robert W. Griffith, MD
December 10, 2004

Introduction

Fibromyalgia affects approximately 6 million Americans - 2% of the population. Its cause is unknown, and doctors are not very successful in treating it. They can try to treat the symptoms, but without a known cause, curing the disease is virtually impossible. Not surprisingly, many sufferers turn to alternative medicine for help.

Investigators have shown an association between sleep-disordered breathing and fibromyalgia, and a connection between obstructive sleep apnea and fibromyalgia has been demonstrated in men with the latter condition. But the vast majority of fibromyalgia sufferers are women. So it was important to find out if a similar connection between breathing problems during sleep and fibromyalgia existed in the 'fair sex'. A study done by New York investigators has been reported in the journal Sleep, and is summarized here.

What was done

Twenty-eight women with fibromyalgia were entered into the study. The diagnosis in each case was based on widely-accepted criteria. Of these 28 subjects, 14 said they snored regularly, 4 snored occasionally, and 10 denied snoring.

A comparative group was provided by 11 women of similar age and weight, but without fibromyalgia, who had what is known as upper-airway resistance syndrome (UARS). UARS is a mild form of obstruction to the upper airway that occurs during sleep, because the soft tissues (the palate and walls of the nasopharynx) collapse slightly. It's a milder form of obstructive sleep-apnea-hypopnea (OSAH), commonly known as sleep apnea, in which a person stops breathing during the night, perhaps hundreds of times, usually for periods of 10 seconds or longer (see first link below).With either UARS or OSAH, increased negative inspiratory pressure (i.e. suction) is needed to allow airflow. This can be measured in the sleep lab, along with the amount of positive airway pressure needed to provide free airflow during inspiratory effort.

All the women in the study had sleep lab examinations, which included measurement of inspiratory airflow and the amount of continuous positive airway pressure (CPAP) needed to overcome any obstruction that was present. (CPAP is commonly used to treat patients with sleep apnea, and there are convenient home devices to administer it.)

What was found

The women with fibromyalgia were average-aged 44, and had average BMIs of 29.

All but one of the 28 women with fibromyalgia had inspiratory airflow limitation; 26 of them had UARS, one had sleep apnea. The entire comparison group with UARS also showed limitation of inspiratory airflow.

Fourteen of the fibromyalgia patients were treated with nasal CPAP for 3 weeks. In these patients, there was a 47% improvement in gastrointestinal symptoms, 46% improvement in fatigue, a 39% improvement in sleep problems, a 33% improvement in rheumatic symptoms, a 30% improvement in pain, and a 23% improvement in 'functional disability'. Five of the patients chose to remain on CPAP therapy after the study finished.

What this means

This small study shows that women with fibromyalgia commonly have limitation to their inspiratory airflow during sleep. Is this a cause or an effect of the disease? The authors of the study believe it's a possible cause. Further studies will doubtless clarify this important question.

Either way, it's good news for fibromyalgia sufferers; the results in the study are impressive. The fact that such a high proportion of these patients have some degree of inspiratory sleep airway obstruction means there's a simple way to help them - CPAP. As the available devices become more user-friendly, this form of therapy may well find a place in the treatment of all, or at least most, cases of fibromyalgia.

Source

• Inspiratory airflow dynamics during sleep in women with fibromyalgia. AR. Gold, F. Dipalo, MS. Gold, J. Broderick, Sleep, 2004, vol. 27, pp. 459--466

Related Links
A New Approach to Fibromyalgia