Abstract
OBJECTIVES: Lifestyle changes-such as adopting healthy nutrition and increasing physical activity-are essential for alleviating symptoms in patients with knee osteoarthritis (OA) and overweight, with weight loss being a key outcome of these changes. Since 2019, healthcare professionals (HCPs) in the Netherlands have been able to refer these patients to a reimbursed combined lifestyle intervention (CLI). This study aims to identify determinants affecting CLI implementation for individuals with knee OA and overweight from both patient and HCP perspectives. DESIGN: Semistructured interviews were conducted in a qualitative study with 23 individuals with knee OA and overweight and 16 HCPs (general practitioners (GPs) and lifestyle coaches). Interviews were transcribed verbatim and coded independently by two researchers using the updated Consolidated Framework for Implementation Research (CFIR). SETTING: Primary care, including GPs and lifestyle coaches from the Greater Rotterdam region in the Netherlands. PARTICIPANTS: 23 individuals with knee OA and overweight and 16 HCPs (GPs and lifestyle coaches). RESULTS: Determinants were explored within four CFIR domains: innovation, outer setting, inner setting and individuals. Key facilitators included recognition of the programme's potential, strong social support and positive participant-coach relationships. Major barriers involved the absence of an exercise component, financial constraints limiting its inclusion, scepticism among GPs about care quality, limited expertise of lifestyle coaches addressing OA-specific needs and difficulties adapting the programme to participants' diverse knowledge levels and health literacy. CONCLUSIONS: To improve the implementation of the CLI for patients with knee OA, it is essential to incorporate a tailored exercise component, strengthen lifestyle coaches' expertise, address financial barriers and build trust among GPs through education and clear communication of programme outcomes. Tailoring the CLI to better meet participant needs is crucial to ensure its long-term effectiveness and sustainability as a treatment for individuals with knee OA and overweight. TRIAL REGISTERATION NUMBER: Netherlands Trial Registry (NL9355).