Medical Evidence Generation, Medical Affairs, Sanofi, Tokyo, Japan.
Department of Health Economics and Outcomes Research, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan.
PLoS One. 2022 Oct 3;17(10):e0272795. doi: 10.1371/journal.pone.0272795. eCollection 2022.
Evidence suggests that older people aged ≥65 years and those aged 60-64 years with chronic medical conditions are at higher risk of developing severe complications due to influenza virus infection when compared with young, healthy adults. Although seasonal influenza is monitored through a nationwide passive surveillance in Japan, influenza related outcomes and medical resource consumption have not been fully documented. This retrospective database study aimed to describe the epidemiological and clinical characteristics of medically attended influenza cases aged ≥60 years and the associated medical resource consumption in Japan. We used clinically diagnosed influenza (CDI) based on the international classification of disease codes, and laboratory-confirmed influenza (LCI) based on influenza test results, to identify the patient population during a total of nine seasons (2010/2011 to 2018/2019). A total of 372,356 CDI and 31,122 LCI cases were identified from 77 medical institutions. The highest numbers of medically-attended influenza episodes were in patients aged 65-74 years and 75-84 years. On average, across seasons, 5.9% of all-cause hospitalizations were attributable to CDI and 0.4% were LCI. Influenza viruses type A and B co-circulated annually in varying degree of intensity and were associated with similar level of complications, including cardiovascular-related. Oxygen therapy increased with age; by contrast, mechanical ventilation, dialysis, blood transfusion, and intensive care unit admission were higher in the younger groups. In-hospital mortality for inpatients aged ≥ 85 years with CDI and LCI were 18.6% and 15.5%, respectively. Considering the burden associated with medically-attended influenza in this population, influenza prevention, laboratory confirmation and clinical management should be emphasized by general practicians and specialists like cardiologists to protect this aging population.
有证据表明，与年轻、健康的成年人相比，年龄≥65 岁的老年人和 60-64 岁患有慢性疾病的人因流感病毒感染而发展为严重并发症的风险更高。尽管日本通过全国性的被动监测来监测季节性流感，但流感相关结局和医疗资源消耗情况尚未得到充分记录。本回顾性数据库研究旨在描述≥60 岁接受医学治疗的流感病例的流行病学和临床特征，以及日本与流感相关的医疗资源消耗情况。我们使用基于国际疾病分类代码的临床诊断流感（CDI）和基于流感检测结果的实验室确诊流感（LCI）来确定患者人群，总共涉及九个季节（2010/2011 年至 2018/2019 年）。从 77 家医疗机构中确定了 372,356 例 CDI 和 31,122 例 LCI 病例。接受医学治疗的流感发作人数最多的是 65-74 岁和 75-84 岁的患者。平均而言，在所有季节中，归因于 CDI 的所有原因住院的比例为 5.9%，归因于 LCI 的比例为 0.4%。甲型和乙型流感病毒每年以不同的强度共同流行，与类似程度的并发症相关，包括心血管相关并发症。随着年龄的增长，氧疗的使用增加；相比之下，机械通气、透析、输血和重症监护病房入院在年轻组中更高。患有 CDI 和 LCI 的≥85 岁住院患者的院内死亡率分别为 18.6%和 15.5%。考虑到该人群中与接受医学治疗的流感相关的负担，全科医生和心脏病专家等专家应强调流感预防、实验室确诊和临床管理，以保护这一年龄段的人群。
