The Cost of Social Care Need in People with Multimorbidity: A Population-Based Cohort Study of 5.7 million Individuals

BackgroundMultimorbidity (the coexistence of two or more long-term conditions) is increasingly prevalent, particularly among older adults, and is a major driver of healthcare expenditure. However, healthcare costs reflect only part of the overall burden. Many people with multimorbidity also depend on social care services for personal support, mobility assistance, and social engagement to preserve independence and quality of life. Despite its significance for individuals, families, and the health system, the economic impact of social care needs related to multimorbidity has not been quantified at a population level in England. MethodsWe conducted a retrospective, population-based cohort study of adults ([≥]18 years) with multimorbidity using data from the CPRD Gold and Aurum datasets covering 1987-2020. Social care needs were identified through coded indicators across three domains (personal care, mobility, and social interaction) and valued using 2019-2020 national unit costs from the Personal Social Services Research Unit (PSSRU). Adjusted per-capita costs were estimated via direct standardisation by age, sex, ethnicity, and socioeconomic deprivation. ResultsThe cohort comprised 5,771,603 adults with multimorbidity (mean age 56.5 years; 55.1% female). Among them, 800,309 individuals (13.9%) had at least one recorded social care need. Personal care accounted for the majority of costs ({pound}3.66 billion; 84.3% of total), affecting 7.3% of the cohort with a mean annual expenditure of {pound}8,736 per user. Mobility needs represented {pound}336.8 million (7.8%) and social interaction needs {pound}346 million (8.0%), with mean annual costs of {pound}1,426 and {pound}709 per user, respectively. Individuals with multiple needs (6.3% of the cohort) incurred mean annual costs of {pound}9,076. Social care needs and costs were higher among older adults, women, and those living in more deprived areas. ConclusionThis study provides the first population-level estimate of social care costs associated with multimorbidity in England. Social care represents an important yet often overlooked component of the broader economic burden of multimorbidity. Costs are predominantly concentrated in personal care and vary systematically by demographic and socioeconomic factors, underscoring potential inequities in service access or provision. Integrating social care within multimorbidity strategies is essential to address the full scale of its societal impact.