A prospective study of costs associated to the evaluation of non‐steroidal anti‐inflammatory hypersensitivity reactions

Abstract

A prospective study of costs associated to the evaluation of non-steroidal anti-inflammatory hypersensitivity reactions To the Editor, Nonsteroidal anti-inflammatory drugs (NSAIDs) are one of the most frequent causes of drug hypersensitivity reactions, affecting 1%-3% of general population; the prevalence of NSAID hypersensitivity is higher in patients with chronic rhinosinusitis, nasal polyposis, asthma, or chronic urticaria, affecting up to 30% of patients 1. The importance of its evaluation resides in the need of NSAIDs as analgesic/anti-inflammatory or antiplatelet therapy 2. This is a prospective, real-life, observational study aimed to evaluate all direct and indirect health costs of patients that consulted in our outpatient clinic for suspected NSAID hypersensitivity reactions. The study lasted from June 1, 2017, to May 31, 2018. The protocol was approved by the local Ethics Committee (code PI4505/2017) and all patients signed an informed written consent. Diagnostic procedures were carried out following the European Network of Drug Allergy/ European Academy of Allergy and Clinical Immunology (ENDA/EAACI) protocol 3. Data concerning medication used for the study (consumption and costs) were collected in a structured way; data costs were provided by the Hospital Pharmacy Service (Table S1). Data about personnel, materials, and infrastructure costs were provided by the Bureau of Management of the Hospital (Table S2). Direct health costs were calculated considering the number of visits, complementary and diagnostic tests performed, and costs for personnel and materials used during the study. Direct nonhealth costs were calculated considering the number of travels and the distance in kilometers from patients' residences to the Allergy Service, applying the amount that the Spanish Authorities pay to public officials for the use of their private car and has been considered as locomotion expenses (€ 0.19 per kilometer) 4 (Figure S1). Indirect costs were based on loss of working hours (absenteeism). The average hourly labor cost in 2018 was estimated at € 27.4 in the European Union (EU) 5. However, this average conceals significant differences between EU Member States. For more details about methods, see Appendix S1. A total of 233 patients were evaluated. Of these, 212 (90.99%) completed the study. Mean age was 50.99 ± 17.56 years. Median age was 52 and interquartile range 38-64 years. There was a predominance of females (67.38%). In 43 out of 233 patients (18.45%), hypersensitivity to NSAIDs was demonstrated. Regarding the type of reaction, in concordance with data published by Doña et al 6 , the number of anaphylaxis was appreciable (eight patients, 18.60%), 29 patients (67.44%) had had skin reactions (10 acute, 16 delayed and three unknown), and six respiratory symptoms (13.95%). Crossreactivity reactions were observed in 25 patients (58.14%), whereas 18 patients were single-drug reactors (Table 1).

Analysis of the Costs Associated With the Elective Evaluation of Patients Labelled as Allergic to Beta-Lactams or Nonsteroidal Antiinflamatory Agents

“…Prospective studies about the costs of evaluating patients labeled as allergic to different drug such as beta-lactam in adults (Blumenthal et al, 2018;Sobrino-García et al, 2019) and children or NSAIDs (Sobrino-García et al, 2020) drive this field forward prioritized.…”

“…There was also a prospective study evaluating the costs of the evaluation of hypersensitivity to NSAIDs in adults. Direct and indirect costs as explained by Soto-Álvarez (2020) were systematically recorded in only a few studies (Blumenthal et al, 2018;Sobrino-García et al, 2019;Sobrino-García et al, 2020). Direct health costs were calculated by Blumenthal et al (2018), who analyzed personnel costs, consumables and space costs.…”

“…Direct health costs were calculated by Blumenthal et al (2018), who analyzed personnel costs, consumables and space costs. Moreover, other studies Sobrino-García et al, 2019;Sobrino-García et al, 2020) considered the number of consultations and all the diagnostic tests performed. Direct non-health costs Sobrino-García et al, 2019;Sobrino-García et al, 2020) were calculated taking into account the number of consultations and the distance from their homes to the Allergy service.…”

“…Moreover, other studies Sobrino-García et al, 2019;Sobrino-García et al, 2020) considered the number of consultations and all the diagnostic tests performed. Direct non-health costs Sobrino-García et al, 2019;Sobrino-García et al, 2020) were calculated taking into account the number of consultations and the distance from their homes to the Allergy service. Finally, indirect costs Sobrino-García et al, 2019;Sobrino-García et al, 2020) were calculated considering the absenteeism of patients.…”

“…Concerning NSAIDs the only prospective elective study (Sobrino-García et al, 2020) included 233 patients (43 positives at the end of the study), with an average cost of €185.30 (maximum €1,055.96).…”