Exposure to several common infections over time may be associated with risk of stroke
Cumulative exposure to five common infection-causing pathogens may be associated with an increased risk of stroke, according to a report posted online today that will appear in the January 2010 print issue of Archives of Neurology, one of the JAMA/Archives journals. Stroke is the third leading cause of death and leading cause of serious disability in the United States, according to background information in the article. Known risk factors include high blood pressure, heart disease, abnormal cholesterol levels and smoking, but many strokes occur in patients with none of these factors. "There is therefore interest in identifying additional modifiable risk factors," the authors write.
Some evidence exists that prior infection with pathogens such as herpes viruses promotes inflammation, contributes to arterial disease and thereby increases stroke risk. Mitchell S. V. Elkind, M.D., M.S., of Columbia University Medical Center, New York, and colleagues studied 1,625 adults (average age 68.4) living in the multi-ethnic urban community of northern Manhattan, New York. Blood was obtained from all participants—none of whom had a stroke—and was tested for antibodies indicating prior exposure to five common pathogens: Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus and herpes simplex virus 1 and 2. A weighted composite index of exposure to all five pathogens was developed.
Participants were followed up annually over a median (midpoint) of 7.6 years. During this time period, 67 had strokes. "Each individual infection was positively, though not significantly, associated with stroke risk after adjusting for other risk factors," the authors write. "The infectious burden index was associated with an increased risk of all strokes after adjusting for demographics and risk factors."
There were several reasons to investigate these five particular pathogens, the authors note. "First, each of these common pathogens may persist after an acute infection and thus contribute to perpetuating a state of chronic, low-level infection," they write. "Second, prior studies demonstrated an association between each of these pathogens and cardiovascular diseases." Studies examining several of these pathogens individually have suggested some may contribute to stroke risk.
"Our study could have potential clinical implications," the authors conclude. "For example, treatment and eradication of these chronic pathogens might mitigate future risk of stroke. Antibiotic therapy directed against C pneumoniae has been tested in randomized controlled trials without evidence of benefit against heart disease. Whether the same holds true for stroke has not yet been established. More studies will be required to further explore infectious burden as a potential modifiable risk factor for stroke."
Source: JAMA and Archives Journals
Articles on the same topic
- Reduced muscle strength associated with risk for Alzheimer'sMon, 9 Nov 2009, 19:50:24 EST
- Exposure to several common infections over time may be associated with risk of strokefrom Science CentricTue, 10 Nov 2009, 9:35:23 EST
- Reduced muscle strength associated with risk for Alzheimer'sfrom Science CentricTue, 10 Nov 2009, 9:35:21 EST
- Reduced muscle strength associated with risk for Alzheimer'sfrom PhysorgMon, 9 Nov 2009, 20:14:23 EST
- Exposure to several common infections over time may be associated with risk of strokefrom PhysorgMon, 9 Nov 2009, 19:49:12 EST
Latest Science NewsletterGet the latest and most popular science news articles of the week in your Inbox! It's free!
Learn more about
Check out our next project, Biology.Net
From other science news sites
Popular science news articles
- Stretchy slabs found in the deep Earth
- Electric fields remove nanoparticles from blood with ease
- Innovative reports to help utility regulators, policymakers and electric industry
- UF creates trees with enhanced resistance to greening
- Climate can grind mountains faster than they can be rebuilt, study indicates
- Smeagol found underground in Brazil: New eyeless and highly modified harvestman species
- New gene that makes common bacteria resistant to last-line antibiotic found in animals and patients in China
- Low-oxygen 'dead zones' in North Pacific linked to past ocean-warming events
- Blocking immune cell treats new type of age-related diabetes
- Forming planet observed for first time
- Assessing the role of negative citations in science
- Obese children's health rapidly improves with sugar reduction unrelated to calories
- Annual Antarctic ozone hole larger and formed later in 2015
- Study reveals the architecture of the molecular machine that copies DNA
- Ancient babies boost Bering land bridge layover