Risk Factors for Unfavorable Outcome in Aneurysmal Subarachnoid Hemorrhage Revisited; Odds and Ends

To evaluate the odds for unfavorable outcome of each risk factor and a combination of them in patients with aneurysmal subarachnoid hemorrhage (SAH) undergoing surgical clipping in Southern Iran.

A total of 367 patients who were operated between March 2007 and March 2016 due to aneurysmal SAH were analyzed according to patients' factors, aneurysm characteristics and intra-operative data. Correlation between outcomes of patients measured by modified Rankin Scale at 6-months with each factor were analyzed. Market Basket analysis was also used to identify the odds of unfavorable outcome for combinations of factors.

A total of 367 patients, including 199 females and 168 males with a mean age of 47.27± 11.53 years, who underwent operation between March 2007 and March 2016 due to aneurysmal SAH were analyzed. Unlike gender, higher age was associated with unfavorable outcome. Ischemic heart disease, Duration of operation and amount of bleeding were also found to increase the odds of unfavorable outcome (p=0.01, 0.02, 0.04 respectively). DM, Cigarette smoking and opium addiction as well as the location and multiplicity of aneurysms did not have an adverse effect on outcome. (p≥0.05).

Among the numerous risk factors presumed to result in unfavorable outcome in aneurysmal SAH, only older age, duration of operation more than 60 minutes, previous known history of ischemic heart disease, poorer clinical grade and intra-operative bleeding more than 500 mL were found to be significant factors.