Epidemiology of COVID-19 and its cardiac and neurological complications among Chinese and South Asians in Ontario: wave 1, 2 and 3

Background — Although we had previously reported the cardiac and neurological outcomes of Chinese and South Asian Ontarians in wave 1 of COVID-19, data on subsequent waves of COVID-19 remain unclear. This is an extension study of this cohort in waves 2 and 3.

Methods — We identified adult Ontarians with a positive COVID-19 PCR test between January 1, 2020 to June 30, 2021 and they were classified as Chinese or South Asians using a validated surname algorithm and compared their outcomes of mortality, cardiac and neurological complications with the general population using multivariable logistic regression models.

Results — Compared to the general population (N = 439,977), Chinese (N = 15,208) were older (mean age 44.2 vs 40.6 years, p < 0.001) while South Asians (N = 46,333) were younger (39.2 years p < 0.001). Chinese had a higher 30-day mortality (Odds ratio [OR] 1.44; 95% CI 1.28-1.61) and hospitalization or emergency department (ED) visits (1.14; 1.09-1.28) and with a trend towards higher cardiac complications (1.03; 0.87-1.12) and neurological complications (1.23; 0.96-1.58). South Asians had a lower 30-day mortality (0.88; 0.78-0.98) but a higher hospitalization or ED visits (1.17; 1.14-1.20) with a trend towards lower cardiac complications (0.76; 0.67-0.87) and neurological complications (0.89; 0.73-1.09). There was also a significant difference in these outcomes between wave 1, 2 and 3, with a greater mortality in all groups in waves 2 and 3.

Conclusions — Ethnicity continues to be an important determinant of mortality, cardiac and neurological outcomes, and healthcare use among patients with COVID-19, requiring further studies to understand factors driving these differences.