3267Impact of recurrent heart failure hospitalizations on cardiovascular mortality in subpopulations with atrial fibrillation and Type 2 diabetes mellitus in a UK database
Authors: Lahoz R , Fagan A , McSharry M , Proudfoot C , Corda S , Studer R 
Published: October 2019

Abstract

Background
Previous studies have suggested that recurrent heart failure hospitalizations (HFh) are a predictor of cardiovascular (CV) and all-cause mortality. Patients with atrial fibrillation (AF) or type 2 diabetes mellitus (T2DM) may be at increased risk.

Purpose
This real-world study examined the impact of recurrent HFh on CV mortality in subgroups of patients with (i) AF or (ii) T2DM in the UK.

Methods
Adult HF patients identified in the CPRD database with a first (index) hospitalization due to HF recorded in the HES dataset from 01/01/2010 to 31/12/2014 and with a claim for AF or T2DM (not mutually exclusive) within the year prior to the index hospitalization were included. Patients were followed until death, transfer out or end of study period (31/12/2017). CV death as primary cause and death due to any cause were evaluated. An extended Cox regression model was used for reporting adjusted relative CV mortality rates for time dependent recurrent HFh.

Results
4585 (53.30%) HF patients with AF and 2344 (27.25%) HF patients with T2DM were included, providing 7846 and 4269 patient-years follow-up, respectively. Patients were relatively old (median [IQR] age of 81 [74–87] and 78 [70–84]) and majority were male (54.2% and 59.1%, respectively). All-cause and CV mortality rates are provided in the table. Compared with those without recurrent HFh, the adjusted hazard ratios (95% CI) for CV death for the AF group were 2.6 (2.3–3.1), 3.2 (2.5–4.1), 5.8 (4.1–8.1) and 6.9 (4.6–10.5) for 1, 2, 3 and ≥4 recurrent HFh, and for the T2DM group were 2.2 (1.7–2.8), 3.3 (2.3–4.7), 5.1 (3.3–8.1) and 3.9 (2.3–6.6), respectively.
All-cause and CV mortality rates 0 Recurrent HFh 1 Recurrent HFh 2 Recurrent HFh 3 Recurrent HFh 4+ Recurrent HFh All patients AF n=3294 (71.8%) n=817 (17.8%) n=282 (6.2%) n=116 (2.5%) n=76 (1.2%) n=4585 (100.0%) Follow-up time (days) from respective recurrent HF hospitalization (median [IQR]) 345 [57–906] 118 [27–522] 80 [19–367] 54 [19–240] 126 [50–379] 254 [42–793] All-cause death (n (%)) 1755 (53.3%) 483 (59.1%) 159 (56.4%) 80 (69.0%) 46 (60.5%) 2523 (55.0%) CV death- primary cause (n (%)) 1059 (32.2%) 325 (39.8%) 109 (38.7%) 56 (48.3%) 34 (44.7%) 1583 (34.5%) T2DM n=1573 (67.1%) n=456 (19.5%) n=170 (7.3%) n=85 (3.6%) n=60 (2.6%) n=2344 (100.0%) Follow-up time (days) from respective recurrent HF hospitalization (median [IQR]) 360 [63–933] 198 [43–545] 68 [17–292] 106 [26–251] 160 [68–389] 267 [49–771] All-cause death (n (%)) 824 (52.4%) 248 (54.4%) 99 (58.2%) 51 (60.0%) 40 (66.7%) 1262 (53.8%) CV death – primary cause (n (%)) 501 (31.9%) 159 (34.9%) 69 (40.6%) 36 (42.4%) 26 (43.3%) 791 (33.8%)

Conclusion
Recurrent HFh are a strong predictor of CV death in the HF population with AF or with T2DM. The risk of CV and all-cause death increases with recurrent HFh in these subpopulations, highlighting the relevance of reducing hospitalizations in the management of HF patients with such comorbid conditions.