Characteristics and laboratory findings on admission to the emergency department among 2873 hospitalized patients with COVID-19: the impact of adjusted laboratory tests in multicenter studies. A multicenter study in Spain (BIOCOVID-Spain study)

Abstract

Identification of predictors for severe disease progression is key for risk stratification in COVID-19 patients. We aimed to describe the main characteristics and identify the early predictors for severe outcomes among hospitalized patients with COVID-19 in Spain. This was an observational, retrospective cohort study (BIOCOVID-Spain study) including COVID-19 patients admitted to 32 Spanish hospitals. Demographics, comorbidities and laboratory tests were collected. Outcome was in-hospital mortality. For analysis, laboratory tests values were previously adjusted to assure the comparability of results among participants. Cox regression was performed to identify predictors. Study population included 2873 hospitalized COVID-19 patients. Nine variables were independent predictors for in-hospital mortality, including creatinine (Hazard ratio [HR]:1.327; 95% Confidence Interval [CI]: 1.040-1.695, p = .023), troponin (HR: 2.150; 95% CI: 1.155-4.001; p = .016), platelet count (HR: 0.994; 95% CI: 0.989-0.998; p = .004) and C-reactive protein (HR: 1.037; 95% CI: 1.006-1.068; p = .019). This is the first multicenter study in which an effort was carried out to adjust the results of laboratory tests measured with different methodologies to guarantee their comparability. We reported a comprehensive information about characteristics in a large cohort of hospitalized COVID-19 patients, focusing on the analytical features. Our findings may help to identify patients early at a higher risk for an adverse outcome.

Keywords:

• COVID-19
• multicenter study
• adjustment
• laboratory tests
• prognosis

Acknowledgements

The authors thank Monserrat Ventura (Spanish Society of Laboratory Medicine-SEQC), who helped by contributing information of EQA for adjustment of laboratory test results.

Author contributions

LGGR conceived and designed the study and supervised the conduct of the trial and data collection. DMG and ABB provided statistical advice on study design and analyzed the data. LGGR and DMG drafted the article, and CMI, JMBR and MJAM contributed substantially to its revision. All the authors contributed to data collection in the participating hospitals and final approval of this article.

Disclosure statement

All authors report no potential conflict of interest. This research did not receive any specific grant from funding agencies in the public, comercial, or not-for-profits sectors