#1415 The association between social isolation and all-cause mortality in patients with chronic kidney disease: a prospective cohort study

Abstract Background and Aims Social isolation has been linked to several diseases and adverse outcomes, such as type 2 diabetes and cardiovascular events. The current study aimed to evaluate the association between social isolation and all-cause mortality in patients with chronic kidney disease (CKD). Method From the UK Biobank, a population-based cohort study, we included 16,250 participants that were diagnosed with CKD and with decreased estimated glomerular filtration rate (eGFR <60 ml/min/1.73 m2) at baseline. Participants were classified as socially isolated if they met at least two of the following criteria: (1) living alone; (2) having close contact with others less than once per month; or (3) lacking leisure or social activities involving interpersonal interaction. The outcome was all-cause mortality obtained from death registries. We performed Cox proportional hazards model to estimate the hazard ratio of social isolation for all-cause death in CKD patients. Results Over a median follow-up of 13.5 years (interquartile range (IQR): 12.6-14.4 years), 3,498 deaths were recorded. The all-cause mortality was 21.5% in the whole cohort, and 20.2%, 55.3% and 62.4% in CKD stage 3, stage 4 and stage 5 respectively. A total of 11.1% of participants were considered to be socially isolated. The results showed that social isolation was independently associated with increased risk for all-cause mortality when compared with no isolation (HR 1.22, 95% CI 1.11 to 1.34) (Fig. 1), after adjusting for age, sex, Townsend deprivation index, education levels, income levels, BMI, smoking status, diet habit, status of physical activity, consumption of alcohol, hypertension, diabetes, Charlson comorbidity index and CKD stages. Subgroup analyses showed that the significant association was only observed in men (HR 1.28, 95% CI 1.14 to 1.45) and in patients with CKD stage 3 (HR 1.23, 95% CI 1.11 to 1.36), but not in women or in those with more advanced renal failure (Fig. 1). Conclusion Social isolation was independently associated with a higher hazard of all-cause mortality in patients with CKD. The association was more significant in men and in patients with mildly decreased renal function.