Risk factors for pertussis hospitalizations in Australians aged 45 years and over: A population based nested case-control study.
Although studies have described factors associated with pertussis hospitalization in children, data on adult hospitalization are sparse. We examined the association between patient characteristics and hospitalization among older adults with pertussis. We conducted a nested case-control study of participants in the 45 and Up prospective cohort in New South Wales, Australia, with an incident pertussis diagnosis during 2006-2012. Cases were defined as those with a hospitalization coded as 'whooping cough' or 'non-specific respiratory disease/cough' between a week prior and 6 weeks after the diagnosis of pertussis based on laboratory tests. Controls were participants diagnosed with pertussis but not hospitalized. Among 265,287 participants, the incidence of pertussis and pertussis hospitalization was 83.9 (95% [confidence interval] CI, 78.7-89.6) and 2.9 (95% CI, 2.1-4.1)/100,000 person-years, respectively. Among 33 cases and 882 controls, factors associated with hospitalization were increasing age (compared to those 45-54 years, adjusted odds ratio [aOR] 5.4 (95% CI, 1.6-18.2) and 8.9 (95% CI, 2.3-34.7) in those aged 65-74 years and 75+ years, respectively) and smoking (ever versus never, aOR 2.37 (95% CI, 1.11-5.06)). The risk of pertussis hospitalization is substantially higher in ≥65 years old. A booster dose of diphtheria-tetanus-pertussis vaccine could be readily integrated into routine vaccination for this age group.
School of Public Health and Community Medicine, University of New South Wales (UNSW), Australia. Electronic address: s.karki@unsw.edu.au.
Surendra
S
Karki
National Centre for Immunization Research and Surveillance of Vaccine Preventable Diseases, The Children's Hospital Network, Westmead, NSW, Australia.
Peter
P
McIntyre
School of Public Health and Community Medicine, University of New South Wales (UNSW), Australia.
Anthony T
AT
Newall
School of Public Health and Community Medicine, University of New South Wales (UNSW), Australia; National Centre for Immunization Research and Surveillance of Vaccine Preventable Diseases, The Children's Hospital Network, Westmead, NSW, Australia.
C Raina
CR
MacIntyre
National Centre for Epidemiology and Population Health, Research School of Population Health, Australian National University, Canberra, ACT, Australia; The Sax Institute, Sydney, Australia.
Emily
E
Banks
School of Public Health and Community Medicine, University of New South Wales (UNSW), Australia; The Sax Institute, Sydney, Australia.
Bette
B
Liu
D000368:Aged; D016022:Case-Control Studies; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000008:administration & dosage; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009517:New South Wales / Q000453:epidemiology; D011446:Prospective Studies; D012307:Risk Factors; D014917:Whooping Cough / Q000453:epidemiology* / Q000517:prevention & control
D015721:Diphtheria-Tetanus-Pertussis Vaccine
Hospitalization; Incidence; Pertussis; Risk; Vaccine