A propensity score matching analysis comparing vascular patients in two different COVID-19 waves

BACKGROUND: The aim of this paper was to analyze differences in clinical presentation, management, and short-term outcomes between vascular patients in two consecutive COVID-19 “waves” (i.e., first wave [W1], second wave [W2]) and the corresponding sub-population of COVID-19 positive (C19pos) patients. METHODS: Data from regional Lombardy (Italy) multicenter registry during W1 (March 8, 2020-May 3, 2020) and W2 (October 3, 2020-Janu-ary 21, 2021) were collected. The primary outcome was 30-day mortality for the entire cohort. Secondary outcomes were 30-day postoperative complication and major amputation rates. Propensity score matching was used to compare waves populations. RESULTS: Data on 1276 patients (W1: N.=659; W2: N.=617) were collected, of which 121 (18.4%) and 50 (8.1%) patients were C19pos in W1 and W2, respectively (P<0.001). Considering the matched entire cohort, elective treatments increased during W2 (11.2% vs. 54.0%, P<0.001). Thirty-day mortality was lower in W2 (12% vs. 5.8%, P=0.001), 30-day postoperative complication rate improved (19.1% vs. 12.0%, P=0.003), and major amputation rates decreased (10.9% vs. 1.1%, P<0.001). Considering the matched C19pos cohorts, thirty-day mortality was similar in both waves (34.9% vs. 32.0%, P=0.786), 30-day moderate postoperative complications reduced in W2 (22.9% vs. 4.0%, P=0.033), and major amputation rates were similar. CONCLUSIONS: Although 30-day outcomes improved during W2 for the entire cohort, C19pos patients experienced similar 30-day mortality and major amputation rates comparing the two waves. Analyzing the pandemic's impact and continued surveillance seems paramount to improve the outcomes of vascular patients.