Yarmohammadi H, et al. - This study was performed to assess the potential role of low serum Ca levels in the occurrence of sudden cardiac arrest (SCA) in the community. Based on this outcome, lower serum Ca levels were independently connected with an increased risk of SCA in the community.

Methods

• Between February 1, 2002, to December 31, 2015, they compared 267 SCA cases [177 (66%) men] and 445 controls [314 (71%) men] from a large population-based study (catchment population ∼1 million individuals) in the US Northwest.
• Patients were incorporated if their age was 18 years or older with available creatinine clearance (CrCl) and serum electrolyte levels for investigations to enable adjustment for renal function.
• For cases, creatinine clearance and electrolyte levels were required to be measured within 3 months of the SCA event.

Results

• Cases of SCA had higher proportions of blacks [31 (12%) vs 14 (3%); P<.001], diabetes mellitus [122 (46%) vs 126 (28%); P<.001], and chronic kidney disease [102 (38%) vs 73 (16%); P<.001] than did controls.
• In multivariable logistic regression analysis, a 1-unit decrease in Ca levels was related to a 1.6-fold increase in odds of SCA (odds ratio, 1.63; 95% CI, 1.06-2.51).
• Blood Ca levels lower than 8.95 mg/dL (to convert to mmol/L, multiply by 0.025) were related to a 2.3-fold increase in odds of SCA as compared with levels higher than 9.55 mg/dL (odds ratio, 2.33; 95% CI, 1.17-4.61).
• Cases of SCA had significantly prolonged corrected QT intervals on the 12-lead electrocardiogram than did controls (465±37 ms vs 425±33 ms; P<.001).