Socioeconomic deprivation is an important risk factor for frailty in middle-aged and older adults

Background Frailty and socioeconomic deprivation are well-established determinants of health, but little is known about their correlation. This study aims to explore the phenotypic connection and the underlying mediation factors between socioeconomic deprivation and frailty. Methods A total of 205,654 eligible participants from UK Biobank were used for the analysis. Frailty phenotype was based on five criteria (weight loss, exhaustion, grip strength, low physical activity, slow walking pace). Socioeconomic deprivation was assessed using the Townsend Deprivation Index from the UK Biobank. Multinomial logistic regression was used to compare the sociodemographic characteristics and long-term conditions of participants with frailty or pre-frailty to those of non-frail participants. Mediation analyses were conducted to confirm whether inflammation and mental state were involved in modulating the association. Results The frailty group has higher socioeconomic deprivation than non-frailty group (P < 0.001). Socioeconomic deprivation was significantly associated with each phenotypic indicator of frailty after adjusting for covariates and multiple comparisons. The mediation analysis revealed that the majority of the inflammatory factors and three psychological indicators had partial and significant mediation effects on the association between TDI and frailty. Conclusions Socioeconomic deprivation is an important risk factor for frailty, and chronic inflammation and mental health partially mediate these associations.