REPLACING AMBULATORY SURGICAL FOLLOW-UP VISITS WITH SMARTPHONE HOME MONITORING: MODELING COST-EFFECTIVE SCENARIOS

Kathleen Armstrong1,2, Peter Coyte2, John Semple1,3 1. Division of Plastic & Reconstructive Surgery; 2. Institute of Health Policy, Management, and Evaluation, University of Toronto; 3. Women’s College Hospital

Introduction Technology is identified as an opportunity to constrain the growth in healthcare costs and eliminate barriers due to distance [1]. Ambulatory surgery offers a large and growing patient population that could benefit from technology. Women’s College Hospital (WCH) has completed a feasibility study using a mobile application (QoC Health Inc, Toronto) to support postoperative care in breast reconstruction patients (Figure 1). This feasibility study suggests that mobile follow-up care adequately detects postoperative complications and eliminates the need for in-person follow-up care. This is concordant with other postoperative telemedicine studies that use telephone follow-up amongst various ambulatory surgery populations [2–4].

Figure 1: QoC Health Inc Mobile Application

Objective This study models the cost-effectiveness of replacing conventional, in-person postoperative follow-up care with mobile follow-up care following ambulatory breast reconstruction. A societal and narrower healthcare system perspective are presented.

Methods TreeAge Software is used to model cost-effective scenarios in which mobile follow-up care replaces in-person follow-up visits over the first postoperative month.

Healthcare System Borne Costs (Table 1): In-person follow-up costs were obtained from WCH and OHIP. In keeping with cost-effectiveness analysis, non-recoupable or sunk costs are not included [5]. Smartphone follow-up costs were provided by QoC Health Inc. Start-up fixed costs were divided over the number of patients served over the useful lifespan of the technology (≈ 5 years). A surgical e-assessment billing fee was assigned based on actual OHIP telemedicine fees. The variable mobile costs are equivalent to $3.50 per patient per day.

Patient Borne Costs were calculated using patient demographic information. In-person follow-up costs include foregone leisure costs, which are based on labour force participation rates and age-sex adjusted average Ontario wages. We presumed that a caregiver equivalent would be present at the first follow-up visit, and assigned a homemaker wage ($11.28/hour) to that person [6]. The hourly rates were multiplied by the travel time and length of the clinic visit. Travel costs were based on distance from home postal code to WCH and Canadian Automobile Association (CAA) Ontario-based average costs. Smartphone follow-up costs were modeled based on a bring-your-own-device (BYOD) format. Each submission takes ≈3 minutes to enter and uses 0.35 MB of data. In the feasibility study, patients submitted once daily for the first two weeks and then once weekly for the next 2 weeks. Leisure time is not interrupted.

In Ontario, 100 MB of data can be purchased for $10; therefore, data costs are negligible. Patient training requires no additional time commitment. �

The effectiveness of mobile and in-person follow-up care is measured as successful surgical outcomes at 30-days postoperative. Prospective trials from the literature in comparable ambulatory surgery patients were used to model effect [2-4].

Table 2 demonstrates how an INB only favours in-person follow-up if a 6 percentage point difference in effect exists between the two follow-up groups and the patient makes < $19.00/hr (highlighted in green). This calculation uses a willingness to pay of $100,000 USD ($109,970 CAD based on the current exchange rate) per quality adjusted life year (QALY), and a 0.04 QALY difference between no complication and minor skin infection, based on the literature [7].

Table 1: Follow-up costs over the first 30 days postoperative

In-person   Mobile (enroll 1000 patients/yr) Healthcare System Costs   Healthcare System Costs Fixed Costs   Fixed Costs Compensation 63.25   Health Centre Setup 1.39 Equipment 1.31   Design/Setup Procedure Prot 6.94 Variable Costs   Training 0.44 Drugs 0.13   Variable Costs Other (Linens) 2.33   Platform Licensing, Accounts 42.00 Clinical assistant 6.25   Standard Support 43.05 Surgeon Fee 26.55   Infrastructure Hosting 19.95 Resident 6.44   Surgeon Fee 22.00 Subtotal H.C. per 30D $174   Subtotal H.C. per 30D $136

 

Patient Costs   Patient Costs Variable Costs   Variable Costs Patient Leisure Time 62.34   Patient Leisure Time 0 Caregiver Wage 33.84   Data (approx. 350 kB per 0 Travel (To and from clinic) 23.24   transmission with photo) Parking 20.00   Subtotal P.C. per 30D $207   Subtotal P.C. per 30D $0 Grand Total (per 1.64 visits) $381   Grand Total (per patient per 30D) $136

Results This modeling assumes that 1,000 patients are enrolled in BYOD mobile follow-up per year and that in-person follow-up patients attend 1.64 visits within the first month postoperatively. It also assumes an equivalent complication rate based on the literature [2-4]. The results of this analysis are summarized in Table 1. From a societal perspective, in-person follow-up care is $245 CAD more expensive than mobile follow-up care. From a healthcare system perspective, in-person follow-up is $38 CAD more expensive. The incremental cost-effectiveness ratio (ICER) is not reportable. The incremental net benefit (INB) of mobile follow-up care reflects the cost difference between the two interventions for any willingness-to-pay value (societal INB=$245 CAD).

Scenario Analysis: Even when in-person follow-up is reduced to one visit per patient over 30D postoperative, mobile follow-up is less costly from a societal perspective. Mobile follow-up care remains cost equivalent to in-person follow-up even when 100% of the mobile follow-up care patients attend one in-person visit.  Two-way Sensitivity Analysis: Patient wage was set between a homemaker and average age-sex adjusted per hour wage. The mobile effect was varied between a 90-96% success rate.  �

Table 2: Two-way sensitivity analysis with varying patient lost leisure time and effectiveness of mobile follow-up care

Patient Lost Leisure Time ($) Delta Effect $33.84 $56.98 $80.12

INB @ 0.00 198.75 236.70 274.65

INB @ -0.02 110.77 148.72 186.67

INB @ -0.04 22.80 60.748 98.70

INB @ -0.06 -65.18 -27.23 10.72

Probabilistic Sensitivity Analysis (Figure 2): In all 100,000 simulations, mobile follow-up care was cheaper than in-person follow-up care from a societal perspective. The distributions assigned simulated 50% of scenarios where mobile follow-up was less effective that in-person follow-up care. Scenarios that are less effective and less costly, can still be considered cost-effective.

Note: WTP = $4,398.80 CAD per effect based on $109,970 CAD per QALY and 0.04 QALY assigned to one superficial skin infection [8].

The Bottom Line Smartphone follow-up care is suitably targeted to low-risk postoperative ambulatory patients. It can be cost-effective from a societal (INB = $245 CAD) and healthcare system perspective (INB = $38 CAD). It remains cost-effective from a societal perspective even when compared to minimal in-person follow-up or even if all patients from the mobile group were to attend one in-person follow-up. Smartphone follow-up care has the potential to generate huge cost savings when applied to a large and growing ambulatory surgery patient population.

Figure 2: Probabilistic sensitivity analysis of mobile vs in-person follow-up care

Less costly, more effective

Less costly, less effective

COI: Dr. Semple is a shareholder in QoC Health Inc. WCH REB and COI management plan approved. Funded by the CIHR e-health catalyst grant.

Breast  Reconstruc-on   Breast  Reconstruc-on   Breast  Reconstruc-on