Negative impact of socioeconomic deprivation on clinical outcomes after cryoablation for atrial fibrillation: 18-month study
Authors: Cimpeanu O , Sim K.Y.T , Lau Y , Dobson R , Marshall G , Padfield G , Wright G , Connelly D.T 
Published: October 2021

Abstract

Background
Lower socioeconomic status has also been shown to associate with higher incidence of atrial fibrillation (AF), increased mortality and morbidity. However, the impact of socioeconomic deprivation on clinical outcomes post AF cryoablation has yet to be investigated.

Aim
To assess the impact of socioeconomic deprivation (as categorised by Scottish Index of Multiple Deprivation, SIMD) on the medical management and clinical outcomes of patients with AF post cryoablation.

Methods
A retrospective study of paroxysmal or persistent AF patients after cryoablation. Parameters included basic demographics, weight, past medical history (hypertension, heart failure, diabetes, stroke, myocardial infarction, sleep apnoea) and alcohol misuse. Medical treatment post ablation (Beta blocker, calcium channel blocker, flecainide, amiodarone, dronaderone, sotolol, anticoagulant use) were also recorded.
Socioeconomic deprivation index, as per SIMD was recorded (1 – most deprived and 10 – least deprived), and accordingly placed into quintile (SIMD 1–2,3–4,5–6,7–8, 9–10). Follow-up for 18 months.
Clinical outcome assessed was rate of readmission for symptomatic AF, rate of heart failure admission, stroke, bleeding diathesis and all-cause mortality.

Results
383 patients were identified: 78 from the lowest quintile (SIMD 1–2), 68 (SIMD 3–4), 64 (SIMD 5–6), 62 (SIMD 7–8), and 111 from the highest quintile (SIMD 9–10). No statistical difference exists between age, gender or weight. Lowest socioeconomic quintile has higher incidence of heart failure (p=0.006) and hypertension (p=0.005) but other past medical history was no different. No difference in incidence of alcohol misuse.
Medicine prescription was not different. Echo features: left ventricular function, atrial size and valvular dysfunction were not different between all groups.
18 months follow-up demonstrated that both readmission for symptomatic documented AF and recurrence of symptoms at 18 months were higher among patients of lowest socioeconomic quintile (Keplan Meier plot, p=0.014 and p=0.006 respectively). Stepwise multiple regression analysis also confirmed multiple socioeconomic deprivation as an independent predictor for more adverse clinical outcome (p=0.02).
Risk of symptom recurrence at 18 months in patients from the least deprived background is less than one third as compared to the ones from the most deprived background (Odd-ratio 0.32 (0.17 - 0.59))
Risk of readmission for AF in patients from the wealthiest socioeconomic group is also less than a third as compared to those of most deprived social group (Odd-ratio 0.31 (95% CI 0.15–0.61)).
Other clinical outcomes including risk of admissions for heart failure, stroke, bleeding diathesis and all-cause mortality was not statistically different across all groups.

Summary
After cryoablation, patients from the lowest socioeconomic group are more likely to experience symptoms recurrence and readmission for symptomatic AF

Funding Acknowledgement
Type of funding sources: None.