Aim The long-term impact of different pain management strategies in older adults remains poorly understood. This population-based retrospective cohort study aimed to identify distinct trajectories of pain management utilization and examine their associations with adverse clinical outcomes in older adults, stratified by frailty status. Methods Using Taiwan’s National Health Insurance Database, we included older adults (≥65 years) who initiated NSAIDs in 2010 and followed them for 8 years. Group-based multi-trajectory modeling and Cox proportional hazards models were employed to assess associations between trajectory groups and subsequent clinical outcomes. Results Among 24,539 participants (mean age 72.7, 58.9% female), four distinct trajectories were identified: short-term (27.6%), mild (31.9%), moderate (21.7%), and extensive (18.9%) utilization. Compared to the short-term group, the extensive utilization group had significantly higher risks of unplanned hospitalization (adjusted HR: 1.36, 95% CI 1.24–1.48), all-cause hospitalization (aHR: 1.43, 95% CI 1.34–1.52), and incident dementia (aHR: 1.27, 95% CI 1.04–1.54). For dialysis, only the extensive group showed higher risk in the age-sex adjusted model (HR: 2.06, 95% CI: 1.00-4.22), but significance was lost after frailty adjustment. No significant differences in all-cause mortality were observed after full adjustment. Conclusion These findings highlight that extensive long-term utilization of pain management strategies in older adults is associated with increased risks of adverse outcomes, particularly hospitalizations and incident dementia, especially among fit older adults, emphasizing the need for careful monitoring and personalized approaches to pain management in older populations, balancing effective pain control with minimization of potential long-term risks.