Feb. 1, 2000 (Washington) -- People afflicted with Lyme disease go on to lead normal lives, plagued by the same nettlesome but rarely serious problems that are reported by most people, according to the largest study on the long-term effects of the tick-borne illness.
Those problems include difficulty sleeping and memory loss. "If you asked me, my memory isn't as good as it was 10 years ago either," says lead author Eugene Shapiro, MD, a professor of pediatrics at Yale University School of Medicine. "I think the majority of people have an idea that, 'I am older and not as energetic as I used to be.' From a population standpoint, most people with Lyme disease do well and are aware of what is going on with them."
Lyme disease is carried by a deer tick that transmits the Lyme disease-causing bacteria through its bite. Initially, the bite may cause a distinctive rash, but more serious symptoms may occur over time, including joint pain, headaches, and fatigue. Lyme disease is fairly rare, although Lyme disease "phobia," as one researcher puts it, is quite common. Diagnosis can be difficult, as are decisions about treatment in the absence of a clear diagnosis.
The study involved close to 700 people in Connecticut with suspected Lyme disease. Eighty-six percent had been treated with an antibiotic. The participants were interviewed an average of 4-5 years following their diagnosis. The results of the study appear in the Feb. 2 issue of the Journal of the American Medical Association.
All of the study participants were asked if they thought they had been cured of Lyme disease, and if they had specific symptoms, including joint or muscle pain, memory problems, fatigue and headaches, and how often they experienced them. They were also queried about whether they noticed increasing difficulty with a handful of common activities, such as housework and falling asleep, and whether they reported any declines in mental abilities, including difficulty finding words, naming objects, and forming ideas.
A subset of 212 of these patients were matched with someone who did not have Lyme disease but was close in age and geographic location to those in the study, and asked the same questions. Both groups were also surveyed using a common health status form and a depression-screening tool.
Although nearly 70% of the participants in the Lyme disease group reported "an increasing frequency of symptoms (for example, pain, fatigue) or of difficulty with daily activities (for example, performing housework, exercising) ? few (19%) of these problems were attributable to Lyme disease," the authors write. Virtually an identical percentage of people who never had Lyme disease reported the same problems with the same frequency.
The researchers went one step further and sought to determine whether the people who had been reported as having Lyme disease really did -- by reviewing their medical records and matching findings against the CDC's diagnostic criteria. Only 64% did.
Shapiro cautions against rushing to a diagnosis of Lyme disease, even when a blood test indicates the presence of antibodies to the bacteria that causes the disease. About half of the people tested for Lyme disease will be misdiagnosed by these blood tests, he says. These blood tests should only be considered accurate if there are other clear indications of Lyme disease, such as swollen knee joint problems or paralysis in the face.
"This [study] is good work, and this was not easy to do," Michael Felz, MD, tells WebMD. Felz, an associate professor of family medicine at Medical College of Georgia in Augusta and long-time Lyme disease and tick researcher, reviewed the study for WebMD. "The bottom line is if you have a good solid diagnosis and you have appropriate antibiotic treatment, your likelihood of a good outcome is high and the news remains good 4-5 years out."