Tobacco Use and Chronic Fatigue Syndrome, Fibromyalgia, and Temporomandibular Disorder—Reply

In reply

We appreciate the comments of Dr Jay in reference to our recent article on overlapping syndromes among patients with CFS, FM, and TMD.¹ He asserts that chronic exposure to the neurotoxins contained in tobacco smoke, either through primary or secondary exposure, may account for many of the syndromes themselves. While the assertion that tobacco smoke can produce a variety of neurological symptoms is certainly valid, we do not believe that tobacco or any other agent in isolation can provide a satisfactory explanation for the cause or perpetuation of these syndromes for several reasons. First, although half of the US population is chronically exposed to tobacco smoke, only a small fraction has CFS (0.42%), FM (2%), and TMD (15%).^2- 4 Second, the relationships that are cited by Jay with respect to a higher incidence of musculoskeletal pain and other symptoms among tobacco users are correlational. As such, they do not speak to causation and may simply reflect the use of tobacco as a coping devise or for other (unmeasured) reasons. Third, the theory that withdrawal from nicotine may underlie the cause of these syndromes is unlikely given that withdrawal is an acute event that can produce temporary neurophysiological effects, whereas individuals who meet criteria for these syndromes typically experience symptoms for years. In our opinion, while exposure to tobacco smoke may represent a potential risk factor for compromised health and function, it is most likely only a small piece of the puzzle in understanding CFS, FM, and TMD, and only in the subgroup of individuals who smoke or have excessive passive smoke exposure. Jay might be interested to know that only about 15% of our patients with CFS smoke, and this rate does not differ from clinic patients who do not meet criteria for this illness. Finally, the diagnosis of CFS excludes drug abuse within 2 years prior to the onset of symptoms and therefore does take into account the effects of drugs of addiction.⁵