title: Risk factors for aneurysmal subarachnoid hemorrhage in an Indian population.
abstract: BACKGROUND
  Aneurysmal subarachnoid hemorrhage (aSAH) has a mortality rate as high as 50%. The prevalence of intracranial aneurysms from various parts of India varies from 0.75 to 10.3%, with higher numbers of cases being diagnosed due to the increasing age of the population and improvements in imaging techniques. However, little is known about the attributable risk factors of aSAH in the Indian population.
  
  
  METHODS
  Using a case-control study we estimated the risk of factors such as hypertension, cigarette smoking, alcohol consumption, diabetes mellitus and family history of aSAH in a South Indian population. The population-attributable risk (PAR) of smoking, hypertension and alcohol use was estimated for the South Indian as well as for the general Indian population.
  
  
  RESULTS
  Our results showed that cigarette smoking (OR, 3.59; p < 0.001) and a history of hypertension (OR, 2.98; p < 0.001) were significant risk factors associated with aSAH. When patients were classified by gender, it was observed that being a smoker and having hypertension increased the risk for aSAH by nearly fourfold in men. Among women, hypertension and older age were significant risk factors. The PAR estimates indicated that smoking (OR, 3.59; 95% CI, 2.13-6.06) and hypertension (OR, 2.98; 95% CI, 1.73-5.12) are significant risk factors.
  
  
  CONCLUSIONS
  Hypertension and smoking may be causal risk factors which might also modify the effect of genetic factors that could increase susceptibility to aSAH in the Indian population. Since these risk factors are amenable to effective modification, our findings will be useful for a gender-specific management of aSAH.
authors.affiliation: Human Molecular Genetics Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, India.
authors.forename: Linda
authors.initials: L
authors.lastname: Koshy
authors.forename: H V
authors.initials: HV
authors.lastname: Easwer
authors.forename: S
authors.initials: S
authors.lastname: Premkumar
authors.forename: Jacob P
authors.initials: JP
authors.lastname: Alapatt
authors.forename: A Marthanda
authors.initials: AM
authors.lastname: Pillai
authors.forename: Suresh
authors.initials: S
authors.lastname: Nair
authors.forename: R N
authors.initials: RN
authors.lastname: Bhattacharya
authors.forename: Moinak
authors.initials: M
authors.lastname: Banerjee
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000428:Alcohol Drinking / Q000009:adverse effects / Q000208:ethnology; D016022:Case-Control Studies; D003920:Diabetes Mellitus / Q000208:ethnology; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000208:ethnology; D007194:India / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010375:Pedigree; D015995:Prevalence; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects / Q000208:ethnology; D013345:Subarachnoid Hemorrhage / Q000208:ethnology* / Q000209:etiology*