Working-age adults with diabetes experience greater susceptibility to seasonal influenza: a population-based cohort study.
OBJECTIVE
The aim of this work was to compare the incidence of illness attributable to influenza in working-age adults (age <65 years) with and without diabetes.


METHODS
We performed a cohort study using administrative data from Manitoba, Canada, between 2000 and 2008. All working-age adults with diabetes were identified and matched with up to two non-diabetic controls. We analysed the rates of influenza-like illness physician visits and hospitalisations, pneumonia and influenza hospitalisations, and all-cause hospitalisations. Multivariable regressions were used to estimate the influenza-attributable rate of each outcome.


RESULTS
We included 745,777 person-years of follow-up among 166,715 subjects. The median age was 50-51 years and 48-49% were women; adults with diabetes had more comorbidities and were more likely to be vaccinated for influenza than those without diabetes. Compared with similar adults without diabetes, those with diabetes had a 6% greater (RR 1.06, 95% CI 1.02, 1.10; absolute risk difference 6 per 1,000 adults per year) increase in all-cause hospitalisations associated with influenza, representing a total of 54 additional hospitalisations. There were no differences in the influenza-attributable rates of influenza-like illness (p = 0.06) or pneumonia and influenza (p = 0.11).


CONCLUSIONS
Guidelines calling for influenza vaccinations in diabetic, in addition to elderly, adults implicitly single out working-age adults with diabetes. The evidence supporting such guidelines has hitherto been scant. We found that working-age adults with diabetes appear more susceptible to serious influenza-attributable illness. These findings represent the strongest available evidence for targeting diabetes as an indication for influenza vaccination, irrespective of age.
Department of Public Health Sciences, School of Public Health, University of Alberta, 2-040G Li Ka Shing Center for Health Research Innovation, 8602 112 Street, Edmonton, AB, Canada, T6G 2E1.
Darren
D
Lau
Dean T
DT
Eurich
Sumit R
SR
Majumdar
Alan
A
Katz
Jeffrey A
JA
Johnson
D000328:Adult; D015331:Cohort Studies; D003920:Diabetes Mellitus / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007251:Influenza, Human / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D012621:Seasons; D055815:Young Adult