(HealthDay News) – Cigarette smoking increases the risk of subarachnoid hemorrhage (SAH) in a dose-responsive manner, and cessation correlates with a reduction in SAH risk, according to a study published online Aug 30 in the Journal of Neurology, Neurosurgery & Psychiatry.
To examine the risk of SAH in relation to smoking cessation, Chi Kyung Kim, MD, from Seoul National University Hospital in Korea, and colleagues performed a nationwide multicenter case control study involving 426 SAH patients and 426 matched controls. Structured questionnaires were used to assess lifestyle, medical history, and smoking habits.
The researchers found that 37.4% of SAH patients and 24.2% of controls were current smokers (adjusted odds ratio, 2.84), after adjusting for potential confounders. The risk of SAH was found to increase in a dose-responsive fashion with cumulative dose of smoking (pack years). There was a significant reduction in SAH to 59% with smoking cessation (at least five years). A history of heavy smoking (at least 20 cigarettes per day) correlated with a 2.3-fold increased risk of SAH, compared with participants who had never smoked (P<0.05).
“We have demonstrated that cigarette smoking increases the risk of SAH, but smoking cessation decreases the risk in a time-dependent manner, although this beneficial effect may be diminished in previous heavy smokers,” the authors write. “To forestall tragic SAH events, our results call for more global and vigorous efforts for people to stop smoking.”