BACKGROUND:High rates of unplanned hospital readmissions are a burden on healthcare systems and individuals. This study examined factors at, and after initial hospital discharge and their associations with unplanned hospital readmission for older adults up to six months post-discharge from subacute care. METHODS:Older subacute care patients were surveyed prior to discharge, and assessed monthly post-discharge for six months. Data included the Geriatric Depression Scale, Phone-Fitt sub-scales, Friendship Scale, modified Lubben Social Network Scale, unplanned hospital readmission, self-reported physical capacity and falls in the last month were collected. Regression analyses were used to examine relationships between unplanned hospital readmission and variables that may predispose this outcome. RESULTS:Participants (n = 311) completed the baseline assessment. N = 218 (70%) completed all at six-month post-discharge. Eighty-nine (29%) participants shared 143 readmissions. Those with cancer history (adjusted OR [95% CI]) (1.97 [1.15, 3.39]), neurological disease other than stroke (2.95 [1.32, 6.57]) and dependence on others to assist in bending tasks (1.94 [1.14, 3.29]) at initial discharge were associated with readmission within six months post-discharge. Those who fell in the last month (adjusted OR [robust 95% CI]) (2.28 [1.43, 3.64]), being less physical active (0.98 [0.96, 0.99]), and dependence on others in moving around residence (2.63 [1.37, 5.06]) after initial discharge were associated with a readmission in the next month within six months post-discharge. CONCLUSION:Trials investigating the effectiveness of strategies to reduce falls, build physical capacity, increase physical activity level, and connection with health care services after discharge to prevent readmission are warranted.