One in 26 Americans will develop epilepsy at some point in their lifetime, according to a population-based study.
Lifetime risk up to age 50 was 1.6% and rose to 3.0% at age 80, Dale C. Hesdorffer, PhD, of Columbia University School of Public Health in New York City, and colleagues reported in the Jan. 4 issue of Neurology.
Given the current U.S. population, nearly 12 million individuals (3.9%) can be expected to develop epilepsy in their remaining lifetime, the researchers forecast based on their findings from the population of Rochester, Minn.
However, the data came from individuals diagnosed 31 to 50 years ago, cautioned Edwin Trevathan, MD, MPH, of Saint Louis University School of Public Health in St. Louis, Mo., in an accompanying editorial.
"The authors did the best analysis possible with the data available, but these data from a long-past era of epilepsy classification, diagnosis, and care may not reflect the current reality of neurology practice," he wrote in Neurology.
The study may underestimate lifetime risk of epilepsy -- particularly for males -- since life expectancy has risen in the U.S., the researchers noted.
The lack of surveillance data gives epilepsy a disadvantage in research funding compared with other chronic conditions of similar public health impact, and hampers the public health response to it, Trevathan argued.
"Epilepsy is a common, serious neurologic disorder with a major impact on public health and therefore deserves the best public health response directed by timely high-quality surveillance data," he wrote in the editorial.
Hesdorffer's study marks the first to measure lifetime risk (current age through remaining lifetime, adjusted for competing risk of dying) for epilepsy, which the group called useful both for physicians and public health planning as a forecast of the burden in the community.
"The impact of this calculation is greatest in the elderly who have the highest incidence, an important concern given the aging population," they wrote in the paper.
The group used linked medical records from all facilities in Southeastern Minnesota to identify the 412 Rochester residents with epilepsy onset (two or more unprovoked seizures) from 1960 through 1979.
More cases were diagnosed toward the later portion of the study period, "representing a trajectory of growth and aging of the population," the researchers noted. Lifetime risk -- defined as risk through age 87 -- also increased over time, from 3.5% in 1960–1969 to 4.2% in 1970–1979.
The median age at epilepsy incidence was 25.9 years, but 26.9% were 60 or older at diagnosis.
Cumulative incidence was 0.9% to age 20, 1.7% to age 50, and 3.4% to age 80. This measure diverged from lifetime risk noticeably after age 70 as competing risk of mortality grew.
Men were more likely to develop epilepsy than women (1 of 21 versus 1 of 28).
The researchers noted that these data could be used for individual risk prediction with the usual caveats that lifetime risk was based on population estimates without taking into account individual risk factors and family history.
The projections would likely generalize to other developed countries with comparable sociodemographics but not those with substantially lower life expectancy, they added.
Tuesday, December 28, 2010
New Alert: Risk of Epilepsy Measured, May Be Still Higher
Many of you know that I knew Teena Marie, so since her death last week I've been hit with questions and emails about epilepsy. Fact: with more than 25% of kids with ASD, suffer from Epilepsy and according to this article, we are still learning about the risks. The article appeared @ http://www.medpagetoday.com/Neurology/Seizures/24085