Association of serum albumin level with risk of treatment failure with β-lactam antibiotics for elderly com-munity-acquired pneumonia and the predictive threshold and efficacy

DENG Ziwei; SHU Yuanlu; SHI Zhihua; WANG Jin; DENG Ye; QIU Chengfeng; WANG Hongqiang; DUAN Zhenxing; YAN Yan

doi:10.3969/j.issn.1002-266X.2023.33.004

Abstract：Objective To investigate the relationships between serum albumin(ALB)levels and the risk of treat-ment failure with β-lactam antibiotics in elderly patients with community-acquired pneumonia(CAP)as well as the predic-tive threshold and efficacy.Methods According to serum ALB levels on the day of admission,86 elderly patients with CAP were divided by quartiles into Q1 group,Q2 group,Q3 group,and Q4 group.All the patients received β-lactam anti-biotics,and the treatment response rate was compared between groups.The data on age,sex,comorbidities,laboratory in-dicators,and the CURB-65 severity score were collected.To analyze the association of serum ALB levels with the risk of β-lactam antibiotic failure,we performed univariable Logistic regression analyses to select significant variables,and then in-cluded them along with age and sex as confounding factors in a multivariable Logistic regression model for further analysis.We constructed a restricted cubic spline(RCS)model to determine the serum ALB threshold for the risk of non-response to β-lactam antibiotics.Using the threshold as the grouping criterion,a stratified multivariable Logistic regression analysis was conducted to analyze the relationships between serum ALB levels and the risk of β-lactam antibiotic failure.Results The serum ALB level of the 86 patients with CAP was(29.0±5.1)g/L.Fifty-nine patients responded to β-lactam antibiot-ics,while the remaining 27 patients did not.The response rates in the Q1,Q2,Q3,and Q4 groups were 39.13%,76.19%,71.43%,and 91.48%,respectively.The proportion of patients with a history of chronic obstructive pulmonary disease in the Q1 group was significantly lower than those in the other groups(all P<0.05).The Q4 group showed a signifi-cantly lower neutrophil count and a significantly lower C-reactive protein level than the other groups(all P<0.05).Serum ALB level was negatively associated with the risk of β-lactam antibiotic failure in the elderly patients with CAP:the odds ratio(OR)and 95%confidence interval(CI)were 0.18(0.04-0.78)in the Q2 group,0.19(0.04-0.93)in the Q3 group,and 0.07(0.01-0.46)in the Q4 group(P for trend=0.019).The RCS analysis showed an L-shaped non-linear re-lationship between serum ALB level and the risk of non-response to β-lactam antibiotics,and the serum ALB threshold as-sociated with the risk of treatment failure was 30 g/L.When serum ALB levels were≤30 g/L,the risk of non-response per standard deviation increase in ALB decreased by 82%(OR=0.18,95%CI:0.04-0.58,P<0.05);when serum ALB lev-els were>30 g/L,there was no significant relationship between serum ALB level and the risk of β-lactam antibiotic failure(P>0.05).Conclusions Serum ALB level is negatively correlated with the risk of β-lactam antibiotic failure in elderly patients with CAP.The serum ALB threshold for the risk of non-response to β-lactam antibiotics in elderly CAP patients is 30 g/L,and there is a higher risk of β-lactam antibiotic failure for elderly CAP patients with the serum ALB level within 30 g/L.