Lower respiratory tract infection(LRTI) is a prevalent disease that threatens the health of older people worldwide. Anemia is also a common disorder in the elderly, and its prevalence increases significantly with age. Most factors that contribute to the development of anemia are improvable. Therefore, we investigated whether anemia was a risk factor for LRTI-caused readmission and death in the elderly occurring within 1 year of discharge from the hospital.

Objectives: To investigate the effect of anemia on readmission and deaths in the older adults following lower respiratory tract infection (LRTI)-caused hospitalization.

Design: A retrospective cohort study. Setting and Participants: Older patients (age: ≥ 80 years) hospitalized at the Department of Geriatrics, from March 2016 to December 2019 to undergo treatment for LRTIs were included.

Methods: The patients were divided into two groups (anemia and non-anemia) based on the level of hemoglobin. They were kept under observation till the occurrence of mortality event or 1 year after discharge. The primary follow-up outcome was LRTI-caused readmission and/or death.

Inclusion Criteria:

• Age ≥ 80 years
• lower respiratory tract infection

Exclusion Criteria:

• Died at the time of first admission
• Active malignancy
• Tuberculosis
• Anemia caused by gastrointestinal bleeding of unknown origin
• Achalasia of the cardia
• Could not be followed up after discharge
• Data were missing

Elderly patients (age: ≥ 80 years), hospitalized (from 31 March 2016 to 27 December 2019) at the Department of Geriatrics of a hospital in Beijing, China, and were with lower respiratory tract infection(LRTI) (including pneumonia and acute exacerbation of chronic obstructive pulmonary disease) were included. 215 patients (age: >/=80 years) who were hospitalized due to LRTI and discharged after being cured were studied. Of these 215 patients, 149 belonged to the anemia group, and 66 belonged to the non-anemia group. The mean age of the cohort at the time of inclusion was 88.73 (SD 4.765) years, and 77.2% of the patients were men.