Impact of comorbidities on patients with COVID-19: A large retrospective study in Zhejiang, China

Abstract

Coronavirus disease 2019 (COVID-19) has become a serious public health problem worldwide. Here, we stratified COVID-19 patients based on their comorbidities to assess their risk of serious adverse outcomes. We collected 856 hospitalized cases diagnosed with COVID-19 from 17 January to 7 February 2020, in Zhejiang Province, and analyzed their comorbidities and composite endpoint (including admission to intensive care unit owing to disease progression, shock, invasive ventilation, and death) to determine the relationship between comorbidities and adverse outcomes. The median age of patients was 46 (36-56) years; 439 (51.3%) were men, 242 (28.3%) had comorbidities, and 152 (17.8%) had two or more comorbidities. The most common comorbidity was hypertension (142 [16.6%]), followed by diabetes (64 [7.5%]). Of the 856 patients, there are 154 (18.0%) severe cases. Thirty-two (3.7%) reached composite endpoints, of which 22 (9.1%) were from the comorbidity group and 10 (1.6%) from the non-comorbidity group (P < .001). After adjusting for age and gender status, the risk of reaching the composite endpoint was higher in the group with comorbidity than in that without comorbidity (hazard ratio [HR] 3.04, 95% confidence interval [CI]: 1.40-6.60). HR values for patients with one, two, and three or more comorbidities were 1.61 (95% CI: 0.44-5.91), 3.44 (95% CI: 1.31-9.08), and 6.90 (95% CI: 2.69-17.69), respectively. COVID-19 patients with comorbidities had worse clinical outcomes as compared with those without any comorbidity. The higher the number of comorbidities, the greater was the risk of serious adverse outcomes.

Keywords: COVID-19; adverse outcome; comorbidity.

Figure 1

Comparison of the time‐dependent risk of reaching to the composite endpoints. A, Comparison of time‐dependent risk of reaching the composite endpoints in patients with comorbidities (red curve) and without comorbidities (blue curve). B, Comparison of time‐dependent risk of reaching the composite endpoints among patients without comorbidity (blue curve), with 1comorbidity (red curve), two comorbidities (black curve) and with three or more comorbidities (green curve)

Figure 2

Variables and hazard ratios in cox proportional hazard models. The figure shows the hazard ratio and 95% confidence interval of some variables in the proportional risk model. P value less than .05 is considered to be statistically significant and regards as a risk factor for the occurrence of composite endpoints (admission to intensive care unit [ICU], shock, invasive mechanical ventilation, death). The scale bar in the middle is the hazard ratio. The cox proportional hazard regression model was used to determine the potential risk factors related to the endpoints with the risk ratio and 95% confidence interval (CI) reported. Age and sex status have been adjusted in the model