Hospital Influenza Admissions as a Harbinger for Nursing Home Influenza Cases

J Am Med Dir Assoc. 2020 Jan;21(1):121-126. doi: 10.1016/j.jamda.2019.06.025. Epub 2019 Aug 21.

Abstract

Objectives: To determine temporal associations of local measures of influenza morbidity and mortality by the Centers for Disease Control and Prevention (CDC) with influenza hospitalizations in nursing home residents.

Design: Retrospective, longitudinal panel study.

Setting and participants: Long-stay nursing home residents, aged 65 years or older in 823 nursing homes from 2011 to 2015.

Measures: CDC-reported rates of influenza and pneumonia mortality and laboratory-confirmed influenza hospitalizations. We compared the CDC measures to nursing home resident hospitalizations due to (1) all-cause, (2) a primary diagnosis of respiratory or circulatory illness, and (3) a primary diagnosis of pneumonia or influenza based on Medicare Part A Claims data.

Results: Our final sample included 273,743 unique residents in 819 nursing homes in 108 cities. National laboratory-confirmed influenza-associated hospitalizations for the group aged 65 and older occurred 0 to 1 week prior to nursing home resident influenza-related hospitalizations (Spearman ρ = 0.54). CDC-reported influenza hospitalizations occurred 3 weeks prior to CDC-reported influenza deaths (ρ = 0.59). Nursing home resident influenza hospitalizations occurred 2 weeks before local CDC-reported pneumonia and influenza deaths occurred (ρ = 0.44).

Conclusions/implications: Publicly reported CDC measures correlate well with nursing home hospitalizations for pneumonia and influenza. Rates of laboratory-confirmed influenza hospitalizations (as reported by the CDC) may be a useful surrogate for nursing home influenza outbreaks but should be considered along with local indicators of disease outbreaks. Early community signals could be clinically leveraged as a trigger for increased infection control measures in nursing homes.

Keywords: Human influenza; hospitalization; nursing homes.

MeSH terms

  • Aged
  • Hospitalization
  • Hospitals
  • Humans
  • Influenza, Human* / diagnosis
  • Influenza, Human* / epidemiology
  • Medicare
  • Nursing Homes
  • Retrospective Studies
  • United States / epidemiology