Drs. McCoy and Baer made some important points in their Dec. 2017 article, Neurological Complications of Sjogren’s Syndrome: Diagnosis and Management (32):
Neurological disease is a common complication of Sjogren’s. It can impact both the central and peripheral nervous systems.
Patients with predominant neurological symptoms often lack SS-A and SS-B. A diagnosis in these patients relies heavily on the lip biopsy which is often not reliable (or even available). Patients may have serious neurological problems from Sjogren’s and still not meet the Sjogren's Classification Criteria. Sjogren’s is often diagnosed very late in these patients.
Even when Sjogren’s is recognized, there is still not much of a roadmap for clinicians to follow. Key quotes from the article:
“There are no clinical trials evaluating the efficacy of systemic immune suppressive therapy for peripheral or central nervous system involvement.”
"... there is an urgency to develop appropriate definitions of neurologic complications of SS and clear parameters for clinical improvement.”
This short Rheumatology Advisor article provides an overview of neurological features of Sjogren's. It mentions the importance of small fiber neuropathy, which is underdiagnosed in Sjogren's patients, but like the McCoy and Baer article, fails to adequately address the high prevalence of dysautonomia.
It is frustrating that so little is known about how to assess and treat neurologic complications.
More confounding is that the least attention is paid to the neurologic features that plague the majority with Sjogren's: “brain fog”, headaches, and dysautonomia (33).
Even physical fatigue may be largely neurologically based. Because so little effort has gone into researching fatigue, the actual cause remains unclear. However, it is increasingly understood to be biological in origin, and not simply caused by depression and anxiety that often accompany chronic illness of all types (88).
Most Sjogren's patients have some combination of physical fatigue, brain fog, headache and dysautonomia. Many of them experience all four on a daily basis. Surveys repeatedly identify physical fatigue, brain fog, and pain, not dryness, as the most disabling symptoms for patients. Clinicians without Sjogren's expertise are rarely aware of this. Little is known about the cause, diagnosis, or treatment of these life-changing symptoms. That is why they are often overlooked in the clinical setting.
Sjogren's patients deserve attention to these life-altering manifestations of the disease.