Data from: Use of influenza antivirals in patients hospitalized in Hong Kong, 2000-2015

Objectives: We aimed to describe patterns in the usage of antivirals to
treat influenza virus infection in hospitals in Hong Kong from 2000
through 2015. Methods: We analyzed centralized electronic health records
that included dispensation information and diagnosis codes. Information
collected on admissions included patient age, sex, admission year and
month, and medications dispensed, and were matched with the first 15
discharge diagnosis codes. We divided monthly admission episodes by
relevant population denominators to obtain admission rates, and stratified
analyses by drug type, age group, and diagnosis codes. Results: Amantadine
was used for influenza treatment in the early 2000s but changed with
recommendations to avoid its use in 2006, and is now mainly used to treat
Parkinson's disease. Oseltamivir usage increased substantially in
2009 and is now commonly used, with almost 40,000 hospitalizations treated
with oseltamivir in the years 2012 through 2015, 66% of which was in
persons ≥65 years of age. During the entire study period, of the 98,253
admission episodes in which oseltamivir was dispensed, 40,698 (41%)
included a diagnosis code for influenza, and 80,283 (82%) included any
diagnosis code for respiratory illness. Conclusions: The amount of
oseltamivir used from 2012-15 was comparable to a separate ecological
estimate of around 13,000 influenza-associated hospitalizations per year
on average. We did not have access to individual patient laboratory
testing data.