The (failed) promise of multimorbidity: chronicity, biomedical categories, and public health.

Multimorbidity has become an increasingly prominent lens through which public health focuses on the 'burden' of ill health in ageing populations, with the promise of a more upstream and holistic approach. We use a situational analysis (drawing on documentary analysis and interviews with service providers, policy actors and people living with multiple conditions) in south London, UK, to explore what this lens brings into focus, and what it obscures. Local initiatives mobilised the concept of multimorbidity in initiatives for integrating health care systems and for commissioning for prevention as well as care. However, as the latest of a series of historical attempts to address system fragmentation, these initiatives generated more complexity, and a system orientated to constant transformation, rather than repair or restoration. Service providers and patients continued to struggle to navigate the system. Dominant policy and practice narratives framed patient self-management as the primary route for addressing individualised risk factors on a trajectory to multimorbidity, whereas the narratives of those living with multiple conditions were more oriented to a relational model of health. The findings suggest possibilities and limitations for leveraging the concept of multimorbidity for public health. In this field, the promise arose from its potential to make spaces for a focus on populations, not patients with discrete diseases. Realising this promise, however, was limited by the inherent tensions of biomedical nosologies, which separate discrete diseases within individual bodies, and from epidemiological approaches that reify the socio-material contexts of failing health as risks for individuals.