Abstract
Dear Editor in Chief,
The recent national cohort study published in your journal, drawing on more than 50,000 emergency admissions to critical care units in Scotland, offers valuable insight into the role of socioeconomic deprivation in shaping outcomes after critical illness. 1 Even after adjusting for age, comorbidity burden, acute physiology and diagnostic category, patients from the least deprived areas had significantly lower 1-year mortality. The clear gradient in emergency readmissions, with the most deprived groups experiencing higher rates of subsequent hospital use, further underscores the influence of socioeconomic circumstances on longer-term recovery.
These findings prompt reflection on how risk adjustment is currently undertaken within UK critical care. ICNARC’s models were designed to enable fair and clinically meaningful comparisons between units, with a justified emphasis on physiological severity, age and pre-existing illness. As far as we are aware, socioeconomic status is not included as a predictor in the current modelling framework, a decision that reflects both practical considerations and the evidence base available when these models were developed. That said, the Scottish study provides compelling evidence that deprivation remains an independent determinant of outcome, even after adjustment for all factors currently incorporated into ICNARC’s approach.
This raises the question of whether socioeconomic information could add value when seeking to understand variations in outcomes. The study suggests that deprivation may capture aspects of vulnerability, multimorbidity patterns, timing of presentation and recovery environments that are not reflected in acute physiological scoring or comorbidity indices. These influences are widely recognised in health-services research, 2 and are increasingly understood to affect not only the risk of critical illness, but the trajectory of recovery once patients leave hospital. Exploring the inclusion of socioeconomic data in future iterations of ICNARC’s modelling would not imply using deprivation as a performance measure, nor altering the central role of clinical judgement. Rather, it would provide an opportunity to assess whether incorporating such information improves calibration, reduces residual confounding or helps contextualise comparisons between units serving populations with differing levels of need. The gradient demonstrated in the Scottish cohort suggests that this exploration could be worthwhile.
The findings reported in your journal make a timely contribution to the ongoing conversation about equity and outcome measurement in critical care. They highlight that socioeconomic circumstances continue to shape outcomes even within a universal healthcare system, and that these influences extend well beyond the acute episode. In this context, reconsideration of how socioeconomic status might be accounted for within risk adjustment would seem both reasonable and potentially valuable.
