Impact of the COVID-19 Pandemic on Primary Care Referral Patterns and Resource Utilization in a Hospital Emergency Department: A Comparative Pre- and Post-Pandemic Study

Background: The COVID-19 pandemic profoundly disrupted healthcare utilization patterns at both primary care (PC) and hospital emergency department (ED) levels. This study aimed to assess the impact of the pandemic on referral patterns from PC to a hospital ED and on the resource consumption associated with those referrals. Methods: describe briefly the main methods or treatments applied. Methods: A descriptive, retrospective, longitudinal comparative study was conducted at a first level hospital of Madrid (Spain). All consecutive PC-to-ED referrals received during two observation windows were included: a pre-pandemic period (1 June-31 December 2019; n=946) and a post-pandemic period (1 January-30 June 2022; n=1,797). Sociodemographic characteristics, referral form quality, diagnostic specialty, and in-ED resource utilization variables were collected and compared using χ², Student’s t-test, and Mann–Whitney U tests as appropriate. Results: A total of 2,743 referrals were analyzed. The monthly referral rate increased by approximately 122% between periods (135/month vs 300/month). No significant differences were found in patient age (mean 53.1±18.3 vs 54.9±19.0 years; p=0.015) or sex. Referral form completion improved significantly for clinical history (94.5% vs 98.2%; p<0.001). Orthopedics referrals nearly tripled (5.8% vs 18.4%), while respiratory/COVID-19-related referrals represented 22.0% of the 2022 caseload. ED length of stay between 3 and 6 hours increased from 13.0% to 42.8% (p<0.001), while the need for urgent blood tests fell from 68.9% to 56.0% (p<0.001), hospital admission from 68.4% to 10.9% (p<0.001), and referral to another center from 12.3% to 0.9% (p<0.001). Conclusions: indicate the main conclusions or interpretations. The abstract should be an objective representation of the article, it must not contain results which are not presented and substantiated in the main text and should not exaggerate the main conclusions. After the initial COVID-19 waves, PC-to-ED referrals increased substantially while requiring fewer complementary investigations and generating fewer hospital admissions, suggesting improved coordination and clinical resolution capacity between PC and the ED. These findings have important implications for post-pandemic healthcare planning.