High Dose Influenza Vaccine in Nursing Home

• Total Number of Hospitalization Claims per Nursing Home Based on Vaccination Status [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  [Linked at the facility level] The primary outcome measure evaluates comparative vaccine effectiveness for hospitalization and mortality of HD vaccine to SD vaccine using Minimum Data Set (MDS).
  
  
• Total Influenza Mortality per Nursing Home Based on Vaccination Status [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  [Linked at the facility level] MDS will be used to determine influenza mortality.
  
  

• Change in Activities of Daily Living (ADL) Scores per NH Resident by Vaccination Status [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  [Linked at the resident level] The secondary outcome measure evaluates comparative vaccine effectiveness for functional status of HD vaccine compared to no or SD vaccine (using MDS). ADL score is a 4 point score (higher is more impaired) for 7 measured domains (maximum 28); 4 point change in composite score is significant. Residents at the highest levels of impairment will be excluded.
  
  
• Difference in ADL Duration per NH Resident by Vaccination Status [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  [Linked at the resident level] Using MDS.
  
  
• New Coded Claims for Stroke, Heart Attack or Pneumonia for a NH Resident [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  [Linked at the resident level] Using MDS, Medicare A and B.
  
  

Lower respiratory tract infection (LRI), which includes pneumonia, bronchitis, and tracheobronchitis, is the leading cause of mortality and hospitalization in older adults and nursing home (NH) residents. Often, the signs and symptoms of pneumonia, in particular, are not apparent in elderly patients, making diagnosis more complicated. In addition, clinician visits to these residents are few and sporadic and radiological facilities are not readily available. LRI may or may not directly lead to hospitalization, but LRIs are associated with considerable other morbidity than can result in hospitalization. Hospitalization rates for NH residents vary considerably between facilities, but the majority of hospitalizations occur during the 12 weeks during which influenza peaks each year.

Influenza vaccination has been associated with reduced hospitalization, strokes, heart attacks and death in non-institutional older adult populations, but the benefit of influenza vaccine for the oldest population has been questioned. The new HD influenza vaccine is considerably more immunogenic in older adults, and has recently been approved for use in individuals aged 65 years and older. No clinical data yet confirm whether the improved immunogenicity translates into added clinical benefit, such as further reduction in hospitalization or death.

The primary objective is to:

1. estimate the differences in all-cause hospitalization rates during flu season experienced by long stay nursing home residents, in facilities using the HD vaccine vs. facilities using the SD vaccine, as pilot data to inform feasibility, design and power calculation for a subsequent larger study.
2. To develop estimates, at the nursing home resident level, about the relationship between influenza vaccination status (none, SD, HD) and Medicare Minimum Data Set (MDS) coded claims for all-cause hospitalization and overall mortality among the long-stay residents from a single season 2012-2013, for use in a subsequent longitudinal evaluation of national nursing home data and regional publicly reported influenza severity.