In those with lupus, (also known as systemic lupus erythematosus or SLE), the story of fatigue and cognitive dysfunction is what Dr. Melanie Harrison compares to the story of the “chicken and egg.” Each symptom directly impacts the other and can wreak havoc upon the human body by forcing one to endure an ongoing cycle of confusion caused by exhaustion, which is caused by confusion, which is caused by exhaustion, and so on. Such a scenario is hard for individuals to live with and difficult for physicians to diagnose.
Among the general population of the United States, fatigue is the main complaint in over ten million doctor visits, or one quarter of all visits annually. This is largely because the condition itself is so dynamic; many patients suffering from fatigue often complain of physical fatigue, where joints and bones are just worn out, while others describe more of a psychological fatigue that results from the stresses of life, work and family. Still others complain simply of mental fatigue, when their mind is hazy or not operating as clearly as they believe it should. At different times and in different ways, just about anyone can suffer from one or any combination of these ailments.
Despite such different ways of presenting itself, each variable symptom of fatigue is equally real and can often be much more pronounced in those with lupus. According to Dr. Harrison, those with lupus tend to experience lupus-related fatigue as “something more from inside” the human body. Though the term sounds uncertain, it lends itself to a different, and some may argue deeper, understanding of the symptom in those who experience it as a result of lupus; fatigue is more than mere listlessness. Rather, it is when one has little trouble beginning a task, but instead tires easily and has trouble keeping up (again, whether it be mentally, physically, psychologically, or otherwise).
“Fatigue, especially related to autoimmune diseases like lupus, is often persistent,” Dr. Harrison says. “It’s very intangible, but you know the difference - especially those with lupus know the difference. It’s not the same thing as just having a cold, it’s not the same thing as just not getting a good night’s sleep.”
Along with skin rashes and arthritis, fatigue is among the most common symptoms of lupus. Over 81 percent of those with lupus, both active and inactive, will experience troublesome fatigue that will impair their ability to live normally. Despite this high percentage, fatigue, because of the variability of the symptom and its typically subtle development, is often overlooked by both patients and physicians. Indeed, many times it is only when patients first complain of fatigue that they realize that something has "been off" for quite a while. This, according to Dr. Harrison, is one reason why physicians have had such trouble diagnosing it.
“Because we can’t do a blood test for it, we can’t do an x-ray for it, we don’t have specific questions…it’s really difficult for us to measure it,” says Dr. Harrison. As a result, the medical community has had little chance to study fatigue and, what is infinitely worse, rarely claims success in treating the ailment unless both a trigger and a continuous cause for the symptom are known.
Causes for fatigue can be many, and this is why narrowing down one specific cause can be so difficult. From a physical standpoint, fatigue can be the result of exertion, pain, or illnesses such as multiple sclerosis, rheumatoid arthritis, or lupus; behaviorally, it can be caused by poor sleep, substance abuse, stress, or any other type of disruption in daily activities; and psychologically, it may result from neuropsychiatric problems such as mood disorders or cognitive dysfunction itself.
Cognitive function refers to the sum of all activities that compose cognitive thought. This includes the taking in of new information, interpretation of information, creating and storing new memories, problem solving, etc. If any cognitive processes are disrupted, one is said to suffer from cognitive dysfunction.
In those with lupus, 80 percent complain of cognitive problems that interrupt their life. Sometimes this can manifest itself in trivial ways such as forgetting what one is supposed to buy at the supermarket, while at other times more serious information may be in question, e.g., forgetting where to pick up one’s children. Often, cognitive dysfunction can lead to a severe decrease in quality of life because cognitive problems create a sense of insecurity.
“There can be loss of independence, either because you actually can’t do things like pay the bills properly or because you’re afraid that if you try to do something, it’s not going to be done right, so you just avoid those activities,” Dr. Harrison says. “There’s a great deal of anxiety and a great deal of depression associated with it.”
According to Dr. Harrison, there is also a great sense of fear surrounding cognitive dysfunction. Patients worry that the disease will progress, eventually leaving their minds “demented.” Based on her years of study, Dr. Harrison has concluded that in most cases (barring the occurrence of other medical conditions such as recurrent stroke or other conditions affecting the brain) patients suffering from cognitive dysfunction do not experience progressive symptoms.
The causes of cognitive dysfunction are similar to those of fatigue. In those with lupus they can include any sort of disease affecting the central nervous system, any condition affecting the brain, psychiatric disturbances (including any one or combination of 19 neuropsychiatric syndromes outlined by the American College of Rheumatology), fever, medication (such as steroids like prednisone), sleep disturbance, pain, and fatigue. The similarities do not end there.
In those with lupus, cognitive dysfunction, just like fatigue, can range from mild to severe and can manifest itself in any number of ways, leaving patients accurately describing the same symptom while each experiences it differently.
“A lot of people will say that they know they are not thinking as clearly as they did before they developed lupus,” says Dr. Harrison. “Some days are definitely better than others, and some weeks are better than others, and some months are better than others, but they never quite return to what their baseline was before they had the disease.”
There is no definitive treatment for cognitive dysfunction (again, because just as in fatigue, there are no specific causes that always create the condition in the human body).
When placed side by side, the symptoms of fatigue and the symptoms of cognitive dysfunction are strikingly similar and are indicative of a cycle of conditions that can be crippling. Dr. Harrison clearly states the problem when she says that, “thinking becomes more difficult when you’re fatigued and when you’re concentrating on thinking clearly, it causes fatigue because your thinking is impaired. Now, which of these started this vicious cycle?”
For those with lupus, a good night of sleep is among the most valuable activities in which one can engage in order to stay healthy and avoid symptoms of the disease like fatigue and cognitive dysfunction. Unfortunately, 61 percent of those with lupus claim that they do not feel refreshed after a night of sleep. Typically, those with lupus have sleep problems that may include any or all of the following:
Another element of sleep disorder Dr. Harrison identifies is what she calls “sleep phobia”:
“Lupus patients tend to lay awake and are concerned about not sleeping, but what happens when you’re thinking, ‘Oh my God, I’m not falling asleep and I have so much to do tomorrow?’” says Dr. Harrison. “The more anxious you get, the less likely that you’ll be able to fall asleep or sleep well when you do fall asleep.”
As stated earlier, lack of sleep can lead to fatigue and can cause great anxiety, but it can also lead to feelings of depression, which can worsen the symptoms of cognitive dysfunction and make sleep more difficult, creating yet another “chicken and egg” scenario where one condition furthers the other in a reciprocal motion.
In those with lupus, as in the general population, musculoskeletal problems such as arthritis account for a significant portion of the patient complaints. Musculoskeletal problems are commonly cited as a cause for fatigue. Typically, these are not chronic, but in those with lupus, there are joint and muscle pains that are inflammatory and therefore more difficult to endure.
Of those with lupus, over 95 percent claim to suffer the pain and swelling associated with arthritis (the most common symptom of lupus). An additional 20-30 percent of patients also suffer from fibromyalgia, a condition similar to arthritis where aches and pains are present but fail to show up visibly in physical examinations or on blood tests. Again, these conditions can cause sleep disorders which, in turn, cause both fatigue and cognitive dysfunction.
Anemia is yet another condition that affects many in the general population, but is also commonly associated with lupus, lupus-related fatigue, and cognitive dysfunction. In the bloodstream, iron is responsible for carrying oxygen throughout the body. When a patient is anemic (defined as an iron deficiency), a situation arises in which a patient’s blood cells cannot carry enough oxygen. The body is then forced to cope by drawing more oxygen in through such means as yawning, increasing feelings of fatigue. When those with lupus experience this, they typically experience it as what Dr. Harrison calls “anemia of a chronic disease,” in which patients develop anemia slowly – the result of the inflammation in the body.
“You have enough iron,” Dr. Harrison says, “but your system is just not working well.”
Dr. Harrison stresses that although the medical community does not know everything there is to know about lupus-related fatigue and cognitive dysfunction, they are making great strides forward in their studies.
“The moral of the story is that the cause of fatigue is not clear,” she says, “but we’ve made some progress and are learning more about the topic.”
Dr. Harrison reiterates that the causes for both fatigue and cognitive dysfunction in those with lupus are numerous and can range from separate conditions within the body such as mood disorders, muscle aches, or lung ailments (such as chronic bronchitis) to external factors such as stress at work and in the home or medication use. Regardless of the cause, once the cycle of fatigue and cognitive dysfunction has started, the symptoms can be difficult to handle.
Simply because there are questions left unanswered when dealing with lupus does not mean that physicians have no advice when it comes to limiting the effects of the disease. Dr. Harrison points out, as most medical professionals do, that it is vital to maintain a healthy lifestyle that includes a balanced diet, sufficient sleep, and exercise. Keeping to these standards may not prevent all the symptoms of the disease, but in the long run it will keep one’s body strong and well prepared to deal with whatever lupus-related conditions may arise.Learn more about the HSS SLE Workshop, a free support and education group held monthly for people with lupus and their families and friends.
Summary by James P. O'Rourke