Learning you have a rare disorder like Lambert-Eaton myasthenic syndrome (LEMS) can be frightening. Among the first questions many people have is: How will my lifespan be affected?
The answer often isn’t clear-cut.
What is life expectancy?
Life expectancy is an estimate of how long people will live. That average age is based on their date of birth, where they live, their gender, and a number of other environmental and genetic factors.
Overall, life expectancy does not refer to individuals, but to a population as a whole. Global life expectancy at birth in 2016 was 72.0 years, according to the Wold Health Organization, known as WHO. That was an increase of 5.5 years compared with the year 2000.
For patient populations with rare diseases like LEMS, doctors can make estimates. But life expectancy are rough estimates based on large groups of people. The number of Lambert-Eaton cases is relatively small, so such estimates may not be accurate.
How does LEMS affect life expectancy?
Life expectancy for people with LEMS depends on a number of factors, including the severity of their condition, the symptoms they experience, and the underlying cause of their disease. The most important factor that affects life expectancy for patients with LEMS is whether or not they have small cell lung cancer (SCLC), which occurs in about 50-60% of Lambert-Eaton cases.
The body produces antibodies against specific proteins that are present on the cancer cells to fight off the cancer. These proteins also are present on the nerve cell endings. In some patients, the antibodies cross-react and also mistakenly attack nerve cell endings, leading to LEMS symptoms. It is not known why, in the remaining 40 to 50% of LEMS cases, the body also produces autoantibodies against proteins in the nerve cell endings.
For patients without SCLC, life expectancy is roughly the same as for individuals without the disease. However, progressive muscle weakness caused by the disease can lead to disability that may make accidents, such as falls, more likely.
For people with LEMS and SCLC, long-term survival is generally poor, with a median survival period of 17-to-24 months from diagnosis.
Last updated: Nov. 12, 2019
Lambert-Eaton News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified healthcare providers with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.