Objectives: To assess the hypothesis of the existence of differential therapeutic effort according to the socioeconomic status of the patients admitted to the hospital by acute myocardial infarction.
Patients and methods: We study retrospectively 592 patients admitted to the intensive care units from six public hospitals from the Spanish region of Valencia, using data from two cohort studies focused on the study of in-hospital inequalities in health. The socioeconomic status was measured using the British occupational classification. The therapeutic effort predicted for the severity of illness was determined using a regression model that included the logarithm of Therapeutic Intervention Scoring System (TISS) score as the dependent variable and Simplified Acute Physiology Score (SAPS) score and Killip group as predictors. The patients whose observed TISS was 3 or more pointless than predicted were considered as infra-treated. The effect of potential confounders was controlled using unconditional logistic regression analysis.
Results: The proportion of infra-treated patients was inversely related to socioeconomic status chi 2 for tendency = 4.31, P = 0.0378). The logistic regression analysis showed a negative association between age and therapeutic effort (p < 0.0001) but not between therapeutic effort and socioeconomic status, after controlling the effect of age (p = 0.2150).
Discussion: Our results suggest that older patients receive less relative therapeutic effort, measured by TISS score, than younger patients. The differential therapeutic effort observed in the crude analysis seem attributable to the higher age of the patients in the lower socioeconomic strata.