Background: Postoperative functional status is a concern in elderly patients. Previously, we reported that administration of non-steroidal anti-inflammatory drugs (NSAIDs) was associated with maintenance of activities of daily living (ADL) scores in elderly patients after hip fracture surgery. The aim of the present study was to investigate whether perioperative NSAIDs administration is related to ADL scores in other age groups after a wide range of surgeries.Methods: The medical records of 368,859 patients aged >= 15 years who underwent surgery under general anesthesia were reviewed.Results: The ADL deterioration ratios of patients aged 70 years or older were significantly higher than those of the younger cohort. NSAIDs administration was associated with postoperative ADL maintenance in elderly patients who underwent various surgeries. However, administration of NSAIDs was not related to ADL maintenance in the younger patients.Conclusions: Postoperative ADL deterioration incidences were higher in elderly patients than in younger patients. Perioperative administration of NSAIDs was associated with postoperative ADL maintenance in various surgeries in elderly patients but not in younger patients. The mechanisms of postoperative ADL deterioration are likely different in elderly and younger patients. Copyright (C) 2020, Taiwan Society of Geriatric Emergency & Critical Care Medicine.