Acute primary angle closure during the Omicron outbreak

AIM:To investigate Omicron’s impact on clinical presentation of acute primary angle closure(APAC)in China.METHODS:A consecutive case series with historical controls was conducted at Shenzhen Eye Hospital,the largest specialized hospital in Shenzhen,China.Medical records from a two-month period during the Omicron pandemic(December 1,2022,to January 31,2023)were compared with records from two control groups(12/2018–1/2019 and 12/2021–1/2022)before pandemic.Patients with APAC were included,and the prevalence of APAC and demographic characteristics in Omicron-infected and noninfected patients were compared.RESULTS:Seventy-one(23.43%)out of 303 patients were diagnosed with APAC in the pandemic cohort,which was 2.98 and 2.61 times higher than that in control cohorts(7.87%in 2019,8.96%in 2022,P<0.001).The pandemic cohort has significantly higher Omicron-infected rate(78.87%vs 0 vs 0;P<0.001),lower proportion of glaucoma history(16.90%vs 42.86%vs 41.67%,P=0.005),higher surgical rate(95.77%vs 83.33%vs 78.57%,P=0.024),higher total medical costs and larger pupil diameter(5.63±0.15 vs 4.68±0.15 vs 4.69±0.22 mm,P<0.01).In 83%Omicron-infected patients,ocular symptoms appeared within 3d after systemic symptoms onset.In multivariate analysis,Omicron infection(P<0.001)was the only independent predictor of pupil diameter.CONCLUSION:In the Omicron epidemic in China,there is an increase of prevalence and severity of APAC,particularly focusing on the first 3d following infection.