[Association between lipoprotein (a) level and chronic cardio-renal syndrome in elderly patients]

Objective: To explore the relationship between lipoprotein(a) [Lp(a)] and chronic cardio-renal syndrome (CRS) in elderly patients. Methods: Chronic heart failure (CHF) patients age ≥ 65 years old, who hospitalized in the department of Cardiology of Hebei General Hospital from December 2017 to October 2019, were included in this study. According to the estimate glomerular filtration rate (eGFR) level, patients were divided into CRS group (eGFR<60 ml·min^-1·1.73 m^-2) and CHF group (eGFR ≥60 ml·min^-1·1.73 m^-2). The blood index and basic disease information were collected and compared. Left ventricular ejection fraction (LVEF) were measured by echocardiography. The correlation between clinical indicators and cardio-renal function (LVEF and eGFR) was assessed. The multivariate logistic regression analysis was used to evaluate the related risk factors of CRS in elderly patients; subgroup logistic regression analysis was performed according to the basic disease of patients to assess the relationship between Lp(a) and CRS. Results: A total of 172 elderly patients (85 males (49.4%), aged 79 (71, 84) years) were finally enrolled. Among them, 88 cases (51.2%) were in CRS group and 84 cases (48.8%) were in CHF group. Age (80 (74, 84) years old vs. 74 (70, 82) years old) and LP (a) levels (222.0 (112.0, 445.3) mg/L vs. 155.0 (97.0, 348.7) mg/L) were significantly higher in the CRS group than in the CHF group (P<0.05). Lp(a) levels were negatively correlated with LVEF (r=-0.155, P=0.043) and eGFR (r=-0.220, P=0.004) in total cohort. In the subgroup analysis of patients with 2 high-incidence basic diseases (coronary heart disease and hypertension), Lp(a) was negatively correlated with LVEF (r=-0.250, P=0.007) in the coronary heart disease group, and negatively correlated with eGFR (r=-0.233, P=0.013) in the hypertension group. Multivariate logistic regression analysis showed that age (OR = 1.069, 95%CI: 1.017-1.124, P= 0.009) and Lp(a) (OR = 3.719, 95%CI: 1.339-10.326, P = 0.012) were independent correlates of CRS. The results of logistic regression analysis showed that Lp(a) was an independent correlative factor of CRS in the subgroups of coronary heart disease (OR=3.207, 95%CI: 1.129-9.108, P=0.029) and hypertension (OR=3.054, 95%CI: 1.086-8.587, P=0.034). Conclusion: Serum Lp(a) level is independently related with CRS in elderly patients.