Risk Factors for ARDS and Death in Cocid-19

People aged 65+ seemed to have the highest risk to develop acute respiratory distress syndrome (ARDS) and death by  COVID-19 according to Chinese researchers.
The assumed that methylprednisolon would lower the risk of death for COVID-19 patients with ARDS.

The researchers conducted a retrospective study of risk factors for ARDS as a result of COVID-19 and consequent death.
They analysed the data of 201 patients who were admitted with a positive COVID-19 test between december 15 2019 and january 26 2020 in a hospital in Wuhan. The follow up ended february 13 2020.

The subjects were aged between 21 and 83 (median: 51 year; IQR: 43-60).
63,7% was male.
66 (32,8%)  of the subject had comorbidities, like hypertension (39; 19,4%), diabetes (22; 10,9%) and liverdiseases (7; 3,5%).
165 patiënten (82,1%) needed ventilation.
84 (41,8%) developed ARDS and 44 (52,4%) died.

The subjects who developed ARDS showed, more often than patients who didn't develop ARDS, comorbidities like hypertention and diabetes. (Difference between groups resp. 13,7%; 95%-BI: 1,3-26,1 and 13,9%; 95%-BI: 3,6-24,2).  59% presented with dyspnea vs 25,6% of those who didn't develop ARDS.

The largest risk factor associated with ARDS and progression to death was age of 65+. (hazard ratio (HR): 3,26; 95%-BI: 2,08-5,11 and HR: 6,17; 95%-BI: 3,26-11,67).
Other factors were neutropenia and organ and coagulation dysfunction, like high lactate hydrogenase (HR: 1,61; 95%-BI: 1,44-1,79 and HR: 1,30; 95%-BI: 1,11-1,52).

Fever ≥ 39°C was associated with a heightened risk of development of  ARDS (HR: 1,77; 95%-BI: 1,11-2,84), bbut with a lower risk of death (HR: 0,41; 95%-BI: 0,21-0,82).
Treatment with methylprednisolon seemed to lower the risk of death for patients with COVID-19 and ARDS  (HR: 0,38; 95%-BI: 0,20-0,72).

Per February 13, 2020, 144 of the total 201 patients (71.6%) were discharged from hospital.
The median hospital stay was 13 days (IQR, 10-16 days).
13 (6.5%) patients were still hospitalized at that date.


Risk Factors Associated With Acute Respiratory Distress Syndrome and Death in Patients With Coronavirus Disease 2019 Pneumonia in Wuhan, China
Chaomin Wu, MD; Xiaoyan Chen, MD; Yanping Cai, MD; et al

JAMA Intern Med. Published online March 13, 2020. doi:10.1001/jamainternmed.2020.0994
https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2763184


review:

This study was reported in detail.
Not only the educational level of the researchers was reported: trained physicians and medical students, but also previous research with some criticism, statistical analysis and relevant factors.
The report was according to international research standards.
Multiple variables were recorded, including symptoms of self report, multiple diagnostic means, ways of ventilation, etc.
A careful analysis of comorbidities enables good identification of the sample they studied, enabling comparison with other research and patient groups.
They identified variables and measured them, that are symptoms of the dying patient in general,but also found discrepancies.In other words, found variables which are not associated with the death process, suggesting something unknown entered the study and maybe the process of COVID-19.

They mentioned the small sample size, and the limitation of studying the patients of just one hospital.

Flaws which were mentioned were also that the fever of the patients was self reported, measured before admission, and that the difference between groups was small..