Social network and severe lower respiratory tract infections in older adults: findings from a Swedish longitudinal population-based study

Abstract

ObjectivesTo investigate the association between social network and the risk and prognosis of severe lower respiratory tract infections (LRTIs) in older adults. MethodsData from Swedish hospital records were matched with the Swedish National Study on Aging and Care in Kungsholmen (SNAC-K). Social network was operationalized as social connections and social support, based on different self-reported variables, and categorized as low, medium, and high. The risk of severe LRTI and related outcomes were assessed using Cox, Poisson, and logistic regression models where appropriate. ResultsA total of 362 individuals experienced LRTI-related hospitalizations between 2001 and 2016 (479 total hospitalizations). High levels of social support decreased the hazard of incident LRTI by 29% (hazard ratio 0.71, 95% confidence interval [CI] 0.52-0.96), the hospital length of stay by 21% (incidence rate ratio 0.79, 95% CI 0.65-0.97), and the risk of 30-day mortality by 92% (odds ratio 0.08, 95% CI 0.01-0.68), but was a risk factor for 30-day readmission (odds ratio 3.16, 95% CI 1.38-7.24). High levels of social connections were associated with a higher risk of incident LRTI in women and those with dementia and/or slow walking speed (Pinteraction <0.05). ConclusionOlder individuals’ quality of social support seems to be a stronger determinant of LRTI incidence and prognosis than the quantity of their social connections. These findings may inform evidence-based policies aimed at preventing LRTIs in older adults.