关键词: 精神障碍, 医疗相关性肺炎, 医院获得性肺炎, 影响因素分析, 巢式病例对照研究

Abstract: Background　Hospital-acquired pneumonia（HAP）is a high-incidence illness and a major leading cause of death in patients with mental disorders. However，there are few studies on the incidence and risk factors of HAP in these patients. Objective　To explore the incidence and risk factors of HAP in patients with mental disorders，so as to provide a basis for clinical treatment and nosocomial infection prevention and control of this illness. Methods　A nested case-control design was used. Mental disorder patients（n=9 336）who were hospitalized in Mental Health Center，Renmin Hospital of Wuhan University from January 2018 to December 2019 were included in the study cohort，among whom those with HAP were assigned to the case group，and compared to those without HAP（control group）after being matched in a ratio of 1∶3 or less value of ratio based on hospitalization period，ward，age，and duration of observation. The clinical information of all patients was collected，including gender，age，length of stay，routine blood test parameters，combined diseases，use of antipsychotics，combined salivation/swallowing disorder（defined as having obvious dysphagia symptoms or a history of aspiration）. Multivariate Logistic regression analysis was used to explore the risk factors of HAP in patients with mental disorders. Results　Of the participants，124（1.33%）had HAP，and they were compared to 334 controls after matching. The case group had longer mean length of stay，higher prevalence of in-hospital use of clozapine，atypical antipsychotics，and antipsychotics ≥2 types，pneumonia in the past two years，underlying diseases，salivation/dysphagia，hyperglycemia as well as schizophrenia（P<0.05）. Multivariate Logistic regression analysis demonstrated that the longer length of stay〔OR=1.025，95%CI（1.004，1.047）〕，in-hospital use of clozapine 〔OR=3.634，95%CI（1.842，7.171）〕，in-hospital use of two or more types of antipsychotics〔OR=2.653，95%CI（1.380，5.100）〕，prevalence of underlying diseases〔OR=2.268，95%CI（1.167，4.411）〕，prevalence of salivation/swallowing disorder 〔OR=56.726，95%CI（7.534，427.078）〕，and prevalence of hyperglycemia〔OR=4.129，95%CI（1.032，16.520）〕 were risk factors of HAP in patients with mental disorders（P<0.05）. Conclusion　To reduce the incidence of HAP in patients with mental disorders，special attention should be paid to the monitoring，prevention and control of HAP in those using clozapine. The monitoring of HAP should also be strengthened in those with salivation/swallowing disorders，combined use of antipsychotics，having hyperglycemia，underlying diseases and longer hospital stay due to disease conditions.

Key words: Mental disorders, Healthcare-associated pneumonia, Hospital acquired pneumonia, Root cause analysis, Nested case control study