The prognostic values of beta-2 microglobulin for risks of cardiovascular events and mortality in the elderly patients with isolated systolic hypertension

Background: The present study aimed to investigate the effects of serum beta-2 microglobulin (B2M) on the risks of major cardiovascular events (MACEs) and all-cause death in Chinese elderly isolated systolic hypertension (ISH) patients without severe renal insufficiency (estimated glomerular filtration rate [eGFR] <30 ml/min/1.73 m(2)). Materials and Methods: Serum B2M concentration, creatinine-eGFR, and blood pressure variability were evaluated in 460 elderly patients (mean age, 82.6 years; 28 women) with ISH in this observational study. The Cox proportional hazard model was adopted to calculate adjusted hazard ratios (HRs) of risk factors for cardiovascular events and all-cause deaths. Results: During a median follow-up period of 37.6 months, 63 patients (13.7%) died, and 65 patients (14.1%) had MACEs. Multivariable analysis showed that the higher serum B2M concentration (B2M >= 0.28 mg/dl) was an independent predictor of increased risk of MACEs (nonfatal acute myocardial infarction, acute heart failure, ischemic stroke, and cardiovascular deaths) and all-cause death (HR: 2.62, 95% confidence interval [CI]: 1.46-4.69, P = 0.001 and HR: 3.40, 95% CI: 1.78-6.48, P < 0.001, respectively) adjusting for other multiple confounders including creatinine-eGFR and cystatin C. In addition, blood pressure variability derived from ambulatory blood pressure measurement was not associated with incidence of MACEs and all-cause mortality (P > 0.05). Conclusion: Our data suggest that serum B2M concentration may be individually associated with MACEs and all-cause death in elderly ISH patients without severe renal insufficiency even after adjusted for creatinine-eGFR and cystatin C.