Serum Cadmium Level Is Positively Associated with Unruptured Intracranial Aneurysm Incidence

BACKGROUND: Cadmium is a toxic element in cigarette smoke associated with ischemic vascular disease. Its association with cerebral aneurysm is unknown. METHODS: We retrospectively analyzed the medical records of patients with headache who underwent imaging studies between March 2014 and August 2016. An unruptured intracranial aneurysm (UIA) was confirmed by brain magnetic resonance angiography or computed tomography angiography. A control group included age- and sex-matched patients without an UIA. Whole blood and random urine tests were used for detection of cadmium and arsenic levels, respectively. Student t-test was used to compare subject characteristics, mean cadmium and arsenic levels between groups, and differences between groups with small (<4-mm) and large (≥4-mm) UIAs. Multivariate regression analysis was used to identify risk factors for aneurysm incidence. RESULTS: Of 238 patients, 25 had an UIA. Those with an UIA had more pack-years of smoking (19.5±3.8 vs. 12.5±6.8, P=0.044) and higher mean serum cadmium levels (1.77±0.19 vs. 0.87±0.21 µg/L, P=0.027). Arsenic levels showed no difference between groups. (67.4±23.5 vs. 62.2±18.3 µg/L, P=0.458). There were no significantly different demographic, clinical, or laboratory characteristics between small and large aneurysm groups. According to multivariate analysis, smoking (odds ratio [OR], 1.48; 95% confidence interval [CI], 1.06–2.33; P=0.047) and serum cadmium >2.0 mcg/L (OR, 1.39; 95% CI, 1.15–1.84; P=0.043) were associated with aneurysm incidence. CONCLUSION: UIA incidence was associated with pack-years of smoking and serum cadmium level, but aneurysm size was not associated with serum cadmium level.