Lyme disease can cause fever, muscle aches, a typical rash, swollen lymph nodes, and fatigue. Without adequate treatment, it can lead to symptoms of arthritis. It can also lead to short term memory problems and difficulty concentrating. About 20,000 new cases are reported in the United States each year.
“Chronic Lyme disease” is said to be a condition in which symptoms persist for months after adequate treatment. Whether this occurs in humans is controversial.
Sometimes sadness, anxiety, fatigue, arthritis or muscle pain are attributed to chronic Lyme disease or to previous Lyme disease, when, in fact, that is not the best explanation. When that happens, the best treatment may be overlooked.
How Often are Symptoms Incorrectly Attributed to Lyme Disease?
To investigate how often symptoms are attributed to Lyme disease when in fact that is not a good diagnosis, researchers looked at patients who came to a university Lyme Disease Center with ongoing symptoms. They did a rigorous examination to see if Lyme disease was present, or if a different diagnosis was better. Two hundred forty patients were studied. The study was done at the Robert Wood Johnson Medical School and Rutgers University.
In over half the cases, symptoms could not be attributed to Lyme disease.
Why Not Lyme Disease?
These patients came to the clinic with symptoms that had been diagnosed as due to Lyme disease. About 40% had a combination of symptoms, rash and blood tests that did indicate Lyme disease. The others did not.
If Not Lyme, Then What?
One group of patients that did not meet criteria for diagnosing Lyme disease met all the criteria for fibromyalgia, and had no other medical condition.
Another group of patients that did not meet criteria for diagnosing Lyme disease had multiple symptoms that could not be attributed to any medical condition. This group was labeled “Unexplained.”
Comparison Group
For comparison, the investigators included people with treated Lyme disease but no post-Lyme symptoms, and people with a number of unrelated medical conditions.
Differences in Mental and Emotional Measures
The fibromyalgia and unexplained groups were more likely to have lower positive affect (had more negative thinking) and had a greater tendency to catastrophize pain. (Catastrophizing is the tendency to unreasonably expect the worst outcome.)
Other differences:
- About 20% of the fibromyalgia group and about 25% of the unexplained group had depression, compared to 6% of the comparison group.
- More anxiety in the fibromyalgia group (28%) and unexplained group (25%) than in the comparison group (14%).
- About 40% of the fibromyalgia group had a personality disorder compared to about 20% of the other groups.
Treatment is Different
Treatment of Lyme disease usually is antibiotics. But if Lyme disease is not present, treatment of depression or anxiety, if present, may be beneficial.
The researchers conclude, “Our findings suggest that multidisciplinary treatment addressing the physical and often emotional suffering of such patients will be more effective than perpetuating the diagnosis of 'chronic Lyme disease'.”
Source: American Journal of Medicine, 2009; 122: 843-50
