兩所醫院附設護理之家肺炎流行病學

Abstract

研究目的: 隨著長照機構住民人數的逐年上升，這個族群的健康問題也將愈來愈受到重視。文獻顯示，肺炎為長照機構住民轉住院及死亡的主要原因。部分研究指出長照機構肺炎有較高的多重抗藥性菌株感染風險，然而不同的研究間仍存在相當大的差異。了解長照機構肺炎的風險及保護因子，將有助於疾病的預防工作。目前關於長照機構肺炎的流行病學資料多為國外的文獻，國內的研究仍然不多，因此我們希望能藉此研究了解本土護理之家肺炎的發生率、致病原及罹病相關因子，並探討流感疫苗對護理之家肺炎風險的影響。 研究方法: 本研究針對台灣北部兩間醫院附設護理之家的住民，收集自2016年1月1日至2017年12月31日期間之臨床病歷與就醫紀錄，所收集的變項包括年齡、性別、抽菸史、意識、功能、醫療管路、身體質量指數、慢性病、流感疫苗接種情形、住院紀錄、胸部X光、及微生物檢驗結果等。相關性研究為回溯性世代研究，追蹤開始時間為2016年1月1日或2016年1月1日以後之入住機構日期，追蹤結束的時間為住民發生第一次住院、離開機構、死亡、或2017年12月31日，統計方法以存活分析Cox proportional hazard regression model作相關性分析。 研究結果: 本研究對象共有287名住民，平均年齡為78.4±12.6歲，男性有155位(58.8%)，長照機構肺炎發生率為每千人日1.66次。綜合而言，最常檢驗出來的微生物依序為Pseudomonas aeruginosa (18.0%)、Enteric gram-negative bacilii (16.9%)、Coagulase-negative Staphylococci (12.4%)、Staphylococcus aureus (11.2%)、Candida albicans (11.2%)及Acinetobacter baumannii (6.7%)。經由多變量分析後，我們發現以下因子與較高的長照機構肺炎風險相關: 80歲以上之高齡住民(HR:4.58, 95%信賴區間(CI):1.35-15.56, P=0.0147)、完全臥床(HR: 9.25, 95% CI: 3.15-27.20, P<0.0001)、以及氣切管(HR: 5.07, 95% CI: 1.72-14.90, P=0.0032)。2015年年底與2016年年底的流感疫苗接種分別對於次一年度上半年的肺炎發生風險的影響，經多變量分析控制可能的干擾因子後，結果顯示接種疫苗者雖有較低的肺炎風險，然而皆未達統計上的顯著意義(HR:0.64, 95%CI:0.16-2.57, P=0.5320；HR: 0.37, 95% CI: 0.09-1.59, P=0.1809)。 結論: 護理之家肺炎的發生率遠高於社區型肺炎。微生物檢驗結果顯示典型的醫院感染型菌種相當常見，而且有相當高的比率為多重抗藥性菌株。80歲以上、完全臥床狀態、及使用氣切管的住民為肺炎的高危險群。流感疫苗對於肺炎的影響可能因不同年度及不同地域而有所差異。

Objective: As the number of the residents in long-term care facilities (LTCF) increases, the health issues of this population will become more and more important. The literatures revealed that pneumonia was the major cause of hospitalization and death among residents in LTCF. There were some studies reporting that the residents with LTCF-acquired pneumonia were at high risk for multidrug resistant (MDR) pathogens. However, the results varied among different studies. To recognize the potential risk or protective factors will help prevent the disease. However, knowledge about the epidemiology of LTCF-acquired pneumonia almost came from studies oversea. There were still few domestic studies at present. The aim of this study was to assess the incidence, pathogens, and potential predictors of LTCF-acquired pneumonia in Taiwan. Furthermore, the protective effect of influenza vaccine on LTCF-acquired pneumonia was explored. Methods: This study obtained the medical records of the residents from the two hospital-based nursing homes in northern Taiwan during 1 January 2016 to 31 December 2017. The data included age, sex, history of smoking, consciousness status, functional status, use of medical devices, body mass index, chronic diseases, receipt of influenza vaccine, hospitalization records, chest X-ray, and the results of microbiological tests. A retrospective cohort study was conducted to assess the potential predictors. Residents of the two nursing homes at any time from 1 January 2016 to 31 December 2017 were eligible for enrollment and were followed up until occurrence of the first episode of hospitalization, leave of the facility, death, or 31 December 2017, whichever came first. Survival analysis of Cox proportional hazard regression model was used to evaluate the relationships. Result: A total of 287 residents (78.4 ± 12.6 years, 58.8% males) from the two hospital-based nursing homes was enrolled. There were 135 episodes of pneumonia occurring in 85 residents. The incidence of LTCF-acquired pneumonia was 1.66/1000 resident-days. The most common microorganisms identified were Pseudomonas aeruginosa (18.0%), enteric gram-negative bacilii (16.9%), Coagulase-negative Staphylococci (12.4%), Staphylococcus aureus (11.2%), Candida albicans (11.2%) and Acinetobacter baumannii (6.7%). Multivariable analysis revealed that age older than 80 years (hazard ratio (HR):4.58, 95% confidence interval (CI):1.35-15.56, P=0.0147), totally bedridden status (HR: 9.25, 95% CI: 3.15-27.20, P<0.0001), and use of tracheostomy (HR: 5.07, 95% CI: 1.72-14.90, P=0.0032) were independent predictors for LTCF-acquired pneumonia. The residents with influenza vaccination between October and December in 2015 or 2016 had a lower risk of LTCF-acquired pneumonia in the first half of the next year, although the result was not statistically significant (HR:0.64, 95% CI:0.16-2.57, P=0.5320；HR: 0.37, 95% CI: 0.09-1.59, P=0.1809). Conclusion:. The incidence of LTCF-acquired pneumonia was far higher than that of community-acquired pneumonia. The microbiologic study revealed that pathogens typically found in hospital-acquired pneumonia were quite common in LTCF-acquired pneumonia, and most of them were MDR. Age, bedridden status, and use of tracheostomy were useful predictors for LTCF-acquired pneumonia. The protective effect of influenza vaccination on LTCF-pneumonia may vary in different years and in different regions.