Cognitive behavioral therapy (CBT) is known to improve chronic pain management. However, past studies revealed only small to moderate benefits in short-term results, and long-term follow-up studies are lacking. This study aimed to follow an integrated CBT program’s effectiveness 1.5 years after its completion. This observational study was the follow-up on the data collected from our CBT sessions conducted under 3 different studies in 2018 to 2019. Seven assessment items (Numerical Rating Scale, Pain Catastrophizing Scale [PCS], Pain Disability Assessment Scale [PDAS], Patient Health Questionnaire-9 items, Generalized Anxiety Disorder 7, European quality of life 5-dimensions 5-level, and Beck Depression Inventory [BDI]) were statistically analyzed. Thematic analysis was conducted in semi structured interviews. PCS (F= 6.52,P= .003), PDAS (F= 5.68,P= .01), European quality of life 5-dimensions 5-level (F= 3.82,P= .03), and BDI (F= 4.61,P= .01) exhibited significant changes (P< .05), confirmed by pairwisettest, revealing a moderate to large effect size. From post-treatment to follow-up, all scores showed no significant changes (P> .1). In the qualitative study, the analysis revealed 3 subthemes: “Autonomy,” “Understanding of yourself and pain,” and “Acceptance of pain.” Our study suggests that integrated CBT may reduce the scores of PCS, PDAS and BDI, and this effect lasts for at least 1 year. Identified themes support the relevance of mitigative factors in managing chronic pain.