Prognosis of Older Adult Patients Suffering from Atrial Fibrillation and Hypokalemia

Xue-Dong Wang, Yu Wang, Jing Liu, Ji-Wen Yao, Jing Zhang, Yi-Nan Zhang Department of Cardiology, Beijing Hepingli Hospital, Beijing, People’s Republic of ChinaCorrespondence: Xue-Dong Wang, Department of Cardiology, Beijing Hepingli Hospital, No. 18 of Hepingli North Street, Dongcheng District, Beijing, People’s Republic of China, Tel +86 10 5804 3212, Fax +86 10 6429 5714, Email wangxd_fjit@163.comObjective: To examine the effects of hypokalemia on the prognosis of older adult patients with atrial fibrillation (AF).Methods: We enrolled 794 older adult patients ≥ 75 years suffering from AF, and divided them into two groups according to the inclusion and exclusion criteria: Group 1, (hypokalemia group), 246 cases, serum K+< 3.5 mmol/L; Group 2, (normal blood potassium group), 548 cases, 3.5mmol/L≤serum K+< 5.5 mmol/L. The two groups of patients were followed for 70 months to observe the occurrence of clinical events. The primary endpoint was cardiovascular death and the secondary endpoint was all-cause death.Results: The median follow-up time was 15.00 months. In terms of baseline profile characteristics, serum creatinine levels were significantly lower in Group 1 than in Group 2 patients (P=0.002). In terms of the relationship between hypokalemia and clinical outcomes, Kaplan-Meier survival analysis revealed that the incidence of clinical primary endpoint in Group 1 was significantly higher than that in Group 2 (P < 0.001), and the incidence of the secondary endpoint did not differ significantly between the two groups (P> 005). Based on multivariate Cox regression risk model analysis, coronary heart disease, hemoglobin content, serum uric acid and usage of anticoagulant drugs were the independent variables related to the primary endpoint of cardiovascular death (all P< 0.01).Conclusion: The incidence of hypokalemia in older adult patients with AF was 30.98%. Hypokalemia was closely related to the cardiovascular death, and coronary heart disease, hemoglobin content, serum uric acid level, and usage of anticoagulant drugs were the independent risk factors for the primary endpoint event.Keywords: atrial fibrillation, older adult, hypokalemia, prognosis