Cost-effectiveness analysis of nonoperative management versus open and laparoscopic surgery for uncomplicated acute appendicitis in Colombia
Authors: Guevara-Cuellar César Augusto , Rengifo-Mosquera María Paula , Parody-Rúa Elizabeth 
Published: June 2021

Abstract
Background
Traditionally, uncomplicated acute appendicitis (AA) has been treated with appendectomy. However, the surgical alternatives might carry out significant complications, impaired quality of life, and higher costs than nonoperative treatment. Consequently, it is necessary to evaluate the different therapeutic alternatives' cost-effectiveness in patients diagnosed with uncomplicated appendicitis.

Methods
We performed a model-based cost-effectiveness analysis comparing nonoperative management (NOM) with open appendectomy (OA) and laparoscopic appendectomy (LA) in patients otherwise healthy adults aged 18–60 years with a diagnosis of uncomplicated AA from the payer´s perspective at the secondary and tertiary health care level. The time horizon was 5 years. A discount rate of 5% was applied to both costs and outcomes. The health outcomes were quality-adjusted life years (QALYs). Costs were identified, quantified, and valorized from a payer perspective; therefore, only direct health costs were included. An incremental analysis was estimated to determine the incremental cost-effectiveness ratio (ICER). In addition, the net monetary benefit (NMB) was calculated for each alternative using a willingness to pay lower than one gross domestic product. A deterministic and probabilistic sensitivity analysis was performed.

Methods
We performed a model-based cost-effectiveness analysis comparing nonoperative management (NOM) with open appendectomy (OA) and laparoscopic appendectomy (LA) in patients otherwise healthy adults aged 18–60 years with a diagnosis of uncomplicated AA from the payer’s perspective at the secondary and tertiary health care level. The time horizon was five years. A discount rate of 5% was applied to both costs and outcomes. The health outcomes were quality-adjusted life years (QALYs). Costs were identified, quantified, and valorized from a payer perspective; therefore, only direct health costs were included. An incremental analysis was estimated to determine the incremental cost-effectiveness ratio (ICER). In addition, the net monetary benefit (NMB) was calculated for each alternative using a willingness to pay lower than one gross domestic product. A deterministic and probabilistic sensitivity analysis was performed.

Results
LA presents a lower cost ($363 ± 35) than OA ($384 ± 41) and NOM ($392 ± 44). NOM exhibited higher QALYs (3.3332 ± 0.0276) in contrast with LA (3.3310 ± 0.057) and OA (3.3261 ± 0.0707). LA dominated the OA. The ICER between LA and NOM was $24,000/QALY. LA has a 52% probability of generating the highest NMB versus its counterparts, followed by NOM (30%) and OA (18%). There is a probability of 0.69 that laparoscopy generates more significant benefit than medical management. The mean value of that incremental NMB would be $93.7 per patient.

Conclusions
LA is a cost-effectiveness alternative in the management of patients with uncomplicated AA. Besides, LA has a high probability of producing more significant monetary benefits than NOM and OA from the payer’s perspective in the Colombian health system.