Background: Rhabdomyolysis is a common condition in older adults, often associated with falls. However, prognostic factors for rhabdomyolysis have mainly been studied in middle-aged populations. Objective: To test the hypothesis that age influences rhabdomyolysis prognostic factors. Methods: This retrospective single-center observational study included all patients with a creatine kinase (CK) level greater than five times normal, admitted to Rennes University Hospital between 2013 and 2019. The primary endpoint was 30-day in-hospital mortality rate. Results: 343 patients were included (median age: 75 years). The mean peak CK was 21,825 IU/L. Acute renal failure occurred in 57.7% of the cases. For patients aged 70 years and over, the main etiology was prolonged immobilization after a fall. The 30-day in-hospital mortality rate was 10.5% (23 deaths). The Charlson score, number of medications and CK and creatinine levels varied according to age. Multivariate analysis showed age to be a factor that was associated, although not proportionally, with 30-day in-hospital mortality. Conclusion: Factors influencing rhabdomyolysis severity were not randomly distributed according to age. The term rhabdomyolysis encompasses various clinical realities and is associated with different mechanisms. More research is needed to better understand the physio-pathological and prognostic factors of rhabdomyolysis, especially in older adults.