High incidence of hospitalisation due to infectious gastroenteritis in older people associated with poor self-rated health

OBJECTIVES To estimate the incidence and risk factors for gastroenteritis-related hospitalisations in older adults. DESIGN Longitudinal cohort study. PARTICIPANTS The 45 and Up Study is a large-scale Australian prospective study of adults aged ≥ 45 years (mean 62.7 years) at recruitment in 2006-2009. Self-reported demographic, health and dietary information at recruitment from 265,440 participants were linked to infectious gastroenteritis hospitalisation data. OUTCOME MEASURES We estimated the incidence of hospitalisation for infectious gastroenteritis, and calculated HRs using Cox regression, adjusting for sociodemographic, health and behavioural variables, with age as the underlying time variable. RESULTS There were 6077 incident infectious gastroenteritis admissions over 1,111,000 person-years. Incidence increased exponentially with increasing age; from 2.4 per 1000 (95% CI 2.2 to 2.5) in individuals aged 45-54 years to 9.5 per 1000 (95% CI 9.2 to 9.8) in those aged 65+ years. After adjustment, hospitalisation due to infectious gastroenteritis was significantly more common in those reporting use of proton pump inhibitors (HR 1.6, 95% CI 1.5 to 1.7), and those with poorer self-rated health (HR 4.2, 95% CI 3.6 to 4.9). CONCLUSIONS Infectious gastroenteritis results in hospitalisation of approximately 1% of people ≥ 65 years old each year. Early recognition and supportive treatment of diarrhoea in older patients with poorer self-rated health may prevent subsequent hospitalisation.