Comparing the outcomes and costs of cardiac monitoring with implantable loop recorders and mobile cardiac outpatient telemetry following stroke using real-world evidence

Abstract

Aim: Patients with ischemic stroke (IS) commonly undergo monitoring to identify atrial fibrillation with mobile cardiac outpatient telemetry (MCOT) or implantable loop recorders (ILRs). The authors compared readmission, healthcare cost and survival in patients monitored post-stroke with either MCOT or ILR. Materials & methods: The authors used claims data from Optum's de-identified Clinformatics^® Data Mart Database to identify patients with IS hospitalized from January 2017 to December 2020 who were prescribed ambulatory cardiac monitoring via MCOT or ILR. They compared the costs associated with the initial inpatient visit as well as the rate and causes of readmission, survival and healthcare costs over the following 18 months. Datasets were balanced using patient baseline and hospitalization characteristics. Multivariable generalized linear gamma regression was used for cost comparisons. Cox proportional hazard regression was used for survival and readmission analysis. Sub-cohorts were analyzed based on the severity of the index IS. Results: In 2244 patients, readmissions were significantly lower in the MCOT monitored group (30.2%) compared with the ILR group (35.4%) (hazard ratio [HR] 1.23; 95% CI: 1.04-1.46). Average cost over 18 months starting with the index IS was $27,429 (USD) lower in the MCOT group (95% CI: $22,353-$32,633). Survival difference bordered on statistical significance and trended to lower mortality in MCOT (8.9%) versus ILR (11.3%) (HR 1.30; 95% CI: 1:00-1.69), led by significance in patients with complications or comorbidities with the index event (MCOT 7.5%, ILR 11.5%; HR 1.62; 95% CI: 1.11-2.36). Conclusion: The use of MCOT versus ILR as the primary monitor following IS was associated with significant decreases in readmission, lower costs for the initial IS and total care over the next 18 months, significantly lower mortality for patients with complications and comorbidities at the index stroke, and a trend toward improved survival across all patients.

Keywords: ICM; ILR; MCOT; MCT; costs; cryptogenic stroke; health economics; healthcare costs; implantable loop recorder; ischemic stroke; mobile cardiac outpatient telemetry; mortality; readmissions; real-world evidence; stroke.

Figure 1.. Sample population flowchart (patients).

CC: With complication or comorbidity; DRG: Diagnosis related group; ILR: Implantable loop recorder; MCC: With major complication or comorbidity; MCOT: Mobile cardiac outpatient telemetry; WOCC: Without complication or comorbidity.

Figure 2.. Cox proportional hazards adjusted survival for implantable loop recorder and mobile cardiac outpatient telemetry patients.

(A) CPH adjusted survival ILR versus MCOT. All severities. (B) CPH adjusted survival ILR versus MCOT. severity; WOCC. (C) CPH adjusted survival ILR versus MCOT. Severity; CC. (D) CPH adjusted survival ILR versus MCOT. Severity; MCC . Survival rates were calculated for each of the 18 months post-index using CPH regressions, taking into account demographics, health profiles, and index hospitalization details. Shaded areas represent 95% confidence intervals. To mitigate bias from differences in device initiation timing, patients who died in the index month were excluded throughout the analysis. CC: With complication or comorbidity; CPH: Cox proportional hazards; ILR: Implantable loop recorder; MCC: With major complication or comorbidity; MCOT: Mobile cardiac outpatient telemetry; WOCC: Without complication or comorbidity.