Poster Abstract Session: Oh, Those Pesky Viruses!
Thursday, October 27, 2016
Room: Poster Hall
Background: Norovirus is known to exert a significant burden of disease among elderly individuals and is the major cause of acute gastroenteritis outbreaks in long-term care facilities. However, little is known about whether norovirus-associated gastroenteritis is associated with underlying chronic disease among sporadic cases occurring in the community. The goal of our work was to compare rates of norovirus-associated, medically-attended acute gastroenteritis (MAAGE) among elderly members of Kaiser Permanente Northwest (KPNW) with and without a previously-diagnosed, chronic condition.Methods: We identified MAAGE episodes based on ICD-9 and chief complaint codes recorded during health care encounters among KPNW members aged ≥60 years occurring from 4/1/2014-3/31/2015. We recruited a sample of individuals with a MAAGE episode to provide a stool specimen for norovirus laboratory testing. We defined the presence of a chronic condition as having at least one ICD-9 code associated with disease in one of eleven categories (i.e. diabetes, heart disease, kidney disease, cancer, etc.).
Results: We observed 6,238 MAAGE episodes occurring among 117,185 KPNW members aged ≥60 years (53.2 episodes per 1,000 individuals). Of these, 4,881 episodes (78%) occurred among those with at least one chronic condition. Among those sampled, the proportion of individuals testing positive for norovirus was not different between those with (23/367, [6.3%]) and without (10/142, [7.0%]) a chronic condition (p=0.74). Despite similar norovirus positivity rates between the two groups, the incidence of norovirus-associated MAAGE was higher among those with at least one underlying condition (2.6 per 1,000; 95% confidence interval [CI] 1.6-3.9) than those without (0.8; CI 0.4-1.4).
Conclusion: Our findings suggest an increased incidence of norovirus-associated MAAGE among those with a chronic condition, compared to those without. Additional research is necessary to compare norovirus-associated MAAGE among patients with different types of conditions, to determine whether having a chronic condition alters the clinical course and severity of acute norovirus-associated disease, and whether norovirus infection affects chronic disease outcomes.
A. J. Hall,