Tufts Study: Despite Burden, Sjögren’s Syndrome May Not Impede Function

Yesterday, I received an email from the associate director of public relations at Tufts University, Boston Health Sciences Campus. (It was one of those moments in which I pointed incredulously at myself and asked, Me? This Important Person wants to share something with ME?) She thought that Tufts University's latest news release may be of interest to Reasonably Well blog followers, and she was right.

However, after reading the press release, the study abstract, and the actual study, I had several concerns as well as one major agreement. I realize that I am NOT QUALIFIED to evaluate or contradict this research. I'm a very retired RN whose only claim to expertise on Sjogren's syndrome is my personal journey with this disease. I have only respect for these researchers who have extensive education and experience in research, oral health, and neuropsychiatric disease.

So with those caveats in mind, what follows is simply a response to this study from a patient's perspective.

The study, Characterization of cognitive dysfunction in Sjögren’s syndrome patients, was conducted by  Lynn C. Epstein, Gina Masse, Jerold S. Harmatz, Tammy M. Scott, Athena S. Papas, and David J. Greenblatt. This was a small study with only 37 patient participants and 37 control subjects.

Let me begin by discussing this from the February 4th  press release from Tuft's University:

BOSTON (February 4, 2014) —People living with Sjögren’s syndrome, an autoimmune disorder characterized by dry eyes and dry mouth, appear to function at a level comparable to their healthier peers, according to a cross-sectional study published online in advance of print in Clinical Rheumatology. The study by clinicians and researchers at Tufts University reveals that people living with Sjögren’s perceive significant decline in cognitive, psychological and physical function. Nonetheless, despite the burdens of the disease, levels of function approach that of healthy controls. Continue reading here. 

This conclusion from the press release:

“Our results suggest that people living with Sjögren’s still are able to maintain a reasonably high level of function, despite their perception of declining function over time. Sjögren’s can interfere with daily functioning and the burden of illness is very real. Nonetheless, it is apparent that even with these interferences people can compensate and function reasonably well,” said co-principal investigator and first author Lynn C. Epstein, M.D., a psychiatrist and clinical professor of psychiatry at Tufts University School of Medicine.

I have to admit that I felt somewhat irritated at this section of the above quote: "....despite THEIR PERCEPTION of declining function over time." This was not a longitudinal study. Study authors would have no data to support their discussion of length of disease related issues.

The subjects of this study were tested extensively in psychological and cognitive health and function; however the physical testing appears to have been based on a large part from self-reported assessment: Fatigue Severity Scale; and The Short Form 36 (SF-36) which is a survey which measures health-related quality of life HRQOL based on 36 items and eight domain scales. I noticed that the assessment of fatigue -- or vitality as termed in this assessment tool -- was located not in the physical health section but rather in the Mental/Emotional locale. There were no physical evaluations of joint pain, pure neurological problems (as opposed to neuropsychiatric), pulmonary issues, renal problems, hepatic problems, gastrointestinal effects, POTS (postural orthopedic tachycardial syndrome) and other dysautonomia symptoms, to name just a few well-documented extra glandular manifestations of Sjogren's syndrome.

And then there's the issue of fatigue.

Since fatigue is one of my most disabling symptoms of Sjs and I'm a bit touchy about labeling fatigue as an all in your head symptom, I found it interesting that elsewhere in the discussion section of this study, fatigue is included under the description of "neuropsychiatric problems":

Neuropsychiatric problems described in association with Sjögren’s syndrome include a variety of psychiatric disorders, alterations in memory, sleep disturbances, cognitive dysfunction,
and excessive fatigue [10–16, 46–48]. The prevalence of these problems in Sjögren’s patients is variable among studies and case series available in the literature. An important clinical and mechanistic question remains regarding the extent to which these neuropsychiatric and cognitive sequelae of Sjögren’s represent actual components of the underlying autoimmune pathophysiology, as opposed to reactions to the stress, burden, and disability related to dry mouth and dry eyes. (Bolding mine.)

Is this evidence of researcher bias leaning toward the Sjogren's is just dry mouth and dry eyes train of thought? I couldn't say. In my personal experience, my disability from this disease is not related to dry mouth and dry eyes. My dry mouth and dry eyes are major inconveniences. I am truly disabled by the extent of my fatigue and joint pain.

However, I was intrigued by the exhaustive amount of testing on cognitive and psychomotor function which included CANTAB testing:

The CANTAB includes the following modules:
a) Psychomotor Coordination and Motor Speed: The Reaction Time Test measures subject's speed of response to a
visual target where the stimulus is either predictable (simple reaction time) or unpredictable (choice reaction
time). This test requires approximately 5 minutes.
b) Reasoning and Planning Abilities: The Stockings of Cambridge task assesses subject's ability to engage in spatial
problem solving. It makes substantial demands on executive function and is sensitive to frontal lobe deficits. It
requires 7-10 minutes.
c) Memory: There are three modules: (a) The Spatial Working Memory module requires that subjects find a blue
token in a series of displayed boxes and use these to fill up an empty column, while not returning to boxes where a blue token has been previously found. Some studies have shown this to be impaired in CFS patients (Joyce et al 1996). It requires 5-10 minutes. (b) The Pattern Recognition Memory test screens visual recognition memory in a 2-choice forced discrimination paradigm and is sensitive to temporal or hippocampal dysfunctions. It requires about 3 minutes. (c) The Spatial Recognition Memory test is a 2-choice forced discrimination paradigm that requires about 2-3 minutes.
d) Attention: There are two modules: The Auemioflal Shift; Intra/Extra Dimensional Shift task is a test of rule acquisition and reversal, featuring visual discrimination and attentional set shifting. It is sensitive to cognitive dysfunction in Parkinson disease and frontal -lobe deficits and requires approximately 5 minutes. The Sustained Attention: Rapid Visual Information Processing module is a visual continuous performance task (vigilance) with a small working memory component. It is impaired in patients with frontal lobe pathology. Its duration is 4 minutes. 

Digit–symbol substitution test (DSST) was also performed:

The Digit Symbol Substitution Task is a well established psychometric test paradigm which is used to measure general cognitive performance. Subjects must match symbols to digits and press the key which corresponds to the digit. The test is designed as a continous performance task in whcih the subject must accomplish as many as possible correct matches within a three minute test period.

The study's evaluation of CANTAB and DSST testing summarized:

Objective testing of information acquisition and recall using the CANTAB procedures indicated a small but statistically significant mean decrement among Sjögren’s patients compared to controls in the free recall score on verbal recognition memory. Otherwise the groups did not differ on other components of verbal recognition memory, or on scores from the paired associates learning or spatial working memory components of the CANTAB.

This is very good news for those of us who are distinctly uncomfortable with our perception of a change in our brains after Sjogren's syndrome enters our lives. But I find it interesting that my experiences with cognitive and memory issues seem to be directly related to my energy stores. If I were tested when feeling rested and have some modafinil onboard, I would guess that my results would vary a great deal from results obtained during a very low-energy period. As a matter of fact, after exhaustive personal clinical trials, I have developed an equation that accurately describes the relationship of my fatigue levels to cognitive ability:

Tired = Stupid

But I digress. Let's move on to other parts of this study that I find very encouraging. I would wholeheartedly agree with this quote from Dr. Lynn C. Epstein, co-principal investigator, especially sections that I have bolded:

“Our results suggest that people living with Sjögren’s still are able to maintain a reasonably high level of function, despite their perception of declining function over time. Sjögren’s can interfere with daily functioning and the burden of illness is very real. Nonetheless, it is apparent that even with these interferences people can compensate and function reasonably well,” said co-principal investigator and first author Lynn C. Epstein, M.D., a psychiatrist and clinical professor of psychiatry at Tufts University School of Medicine.

Here is my take-away from this piece of research: Patients dealing with Sjogren's syndrome are tough and resilient people with an impressive cache of coping tools. While some of us are severely disabled by this disease, the majority of sjoggies lead productive and active lives in spite of the challenges that this disease brings.

It's a very important message that is often overlooked.

I frequently focus on the disabling features of my disease. It's easy to do since my blog is my own personal soap box to blather away about the physical problems that I deal with daily. But what I often forget is the importance of focus and emphasis on my abilities, not disabilities.

Newly diagnosed Sjogren's patients need to understand that the vast majority of these patients lead lives that are changed by Sjs, yes, but those lives for the most part are ones that include a healthy functioning brain, fulfilling careers, supportive family relationships, and an active social life.

This study is a reminder to us all that life as a sjoggie can be challenging, but can also be fulfilling and productive.

And good.