Effect of socioeconomic status in medical resource use and outcomes in patients with heart failure in integrated care settings: real-world evidence from population-based data of 77,554 patients
Authors: Comin-Colet J , Capdevila C , Vela E , Cleries M , Fernandez C , Alcober L , Calero-Molina E , Hidalgo E , Jose N , Moliner P , Corbella X , Yun S , Jimenez-Marrero S , Garay A , Enjuanes-Grau C 
Published: October 2022

Abstract

Background
Low socioeconomic status (SES) has a negative impact in terms of outcomes and medical resource use despite open access to care in universal health-care systems in patients with heart failure (HF). Whether the breach in outcomes determined by SES inequalities can be mitigated by intensive HF management in integrate care programs is not known.

Purpose
To analyse the effect of SES status on health outcomes before and after a pragmatic implementation of an intensive transitional care nurse-based HF management program integrating hospital and primary care and resources for patients with HF at a high risk of events in a health-care area of 209,255 inhabitants.

Methods
For the purposes of this study, we included all individuals consecutively admitted to hospital with at least one ICD-9-CM code for HF as the primary diagnosis and discharged alive in Catalonia between January, the 1st, 2015 and December, the 31st of 2019. We considered 3 distinct periods of implementation of the HF programme: pre-implementation (2015–2016), transition (2017 start of implementation) and consolidation (2018–2019). To evaluate the efficacy of the programme according to SES strata, we compared outcomes between HF patients of the implementation area and HF patients of the remaining healthcare areas of Catalonia across implementation periods and stratified according to levels of SES. SES was defined based on individual annual income.

Results
We included 77,554 patients in the study: 3,396 in the implementation area and 74, 158 in the rest of Catalonia. Distribution of patients according to SES was: 12,018 (15.5%) high or medium SES, 61,967 (79.9%) low SES and 3,535 (4.5%) very low SES. During the period of the study death occurred in 37,469 (48.3%), clinically related hospitalisation in 41,709 (53.8%) and HF readmission in 29,755 (38.4%).
Multivariate Cox proportional hazards models (Table 1) showed that low or very low SES was associated with worse outcomes compared to patients with high or medium SES. Implementation of HF programme significantly improved outcomes in patients with HF (Figure 1, left column). As shown in Figure 1 central and right columns, improvement in clinical outcomes was observed across all SES strata in patients exposed to the HF programme. The size effect for hospitalisation was more prominent among patients with medium of high SES (47% relative change) compared to patients with low or very low SES (32% relative change). Size effect for mortality did not differ between both strata (10% relative improvement in both groups).

Conclusions
The SES is an independent predictor of mortality, clinically related hospitalisation, and HF hospitalisation in vulnerable patients with HF. The implementation of an intensive transitional care nurse-based HF management program improve clinical outcomes across SES strata. However, the size effect in the prevention of hospitalisation is more pronounced among patients with medium or high SES.

Funding Acknowledgement
Type of funding sources: None.