bims-covirf Biomed News
on COVID19 risk factors
Issue of 2021–08–22
three papers selected by
Catherine Rycroft, BresMed



  1. Euro Surveill. 2021 Aug;26(33):
      BackgroundDeterminants of hospitalisation, intensive care unit (ICU) admission and death are still unclear for COVID-19. Few studies have adjusted for confounding for different clinical outcomes including all reported cases within a country.AimWe used routine surveillance data from Portugal to identify risk factors for severe COVID-19 outcomes, and to support risk stratification, public health interventions, and planning of healthcare resources.MethodsWe conducted a retrospective cohort study including 20,293 laboratory-confirmed cases of COVID-19 reported between 1 March and 28 April 2020 through the national epidemiological surveillance system. We calculated absolute risk, relative risk (RR) and adjusted relative risk (aRR) to identify demographic and clinical factors associated with hospitalisation, ICU admission and death using Poisson regressions.ResultsIncreasing age (≥ 60 years) was the major determinant for all outcomes. Age ≥ 90 years was the strongest determinant of hospital admission (aRR: 6.1), and 70-79 years for ICU (aRR: 10.4). Comorbidities of cardiovascular, immunodeficiency, kidney and lung disease (aRR: 4.3, 2.8, 2.4, 2.0, respectively) had stronger associations with ICU admission, while for death they were kidney, cardiovascular and chronic neurological disease (aRR: 2.9, 2.6, 2.0).ConclusionsOlder age was the strongest risk factor for all severe outcomes. These findings from the early stages of the COVID-19 pandemic support risk-stratified public health measures that should prioritise protecting older people. Epidemiological scenarios and clinical guidelines should consider this, even though under-ascertainment should also be considered.
    Keywords:  COVID-19; death; determinants; hospital admission; intensive care; risk factors
    DOI:  https://doi.org/10.2807/1560-7917.ES.2021.26.33.2001059
  2. Infect Chemother. 2021 Mar;53(1): 13-28
      Severe illness and poor outcome are mainly associated with aging or certain medical comorbidities, especially chronic diseases. However, factors for unfavorable prognosis have not been well described owing to relatively small sample sizes and single-center reports. Therefore, this study aimed to compare the contribution of comorbidities in the development of critical conditions in coronavirus disease 2019 (COVID-19) patients. Pooled estimates of relative risks (RRs) and their 95% confidence intervals (CIs) were calculated by conducting a meta-analysis and network meta-analysis of 18 studies. Chronic obstructive pulmonary disease (COPD) was most strongly associated with the overall critical condition (RR = 4.22, 95% CI = 3.12 - 5.69), followed by cardiovascular disease (CVD) (RR = 3.00, 95% CI = 2.41 - 3.73), malignancy (RR = 2.91, 95% CI = 2.16 - 3.91), cerebrovascular accident (CVA) (RR = 2.86, 95% CI = 1.95 - 4.19), diabetes (RR = 2.10, 95% CI = 2.16 - 3.91), hypertension (RR = 2.02, 95% CI = 1.82 - 2.23), and chronic kidney disease (RR = 2.00, 95% CI = 1.36 - 2.94). The presence of comorbidities except for chronic liver disease and chronic kidney disease significantly increased the risk of severe infection, intensive care unit (ICU) admission, and cardiac injury in the subgroup analysis by types of critical conditions. Preexisting hypertension and diabetes additionally increased the risk of acute respiratory distress syndrome (ARDS). Among comorbidities, COPD had the highest probability of leading to severe COVID-19, ICU admission, and liver injury, while malignancy was most likely to cause ARDS and cardiac injury. In summary, preexisting COPD, CVD, CVA, hypertension, diabetes, and malignancy are more likely to worsen the progression of COVID-19, with severe infection, ICU admission requirement, and cardiac injury development.
    Keywords:  Acute respiratory distress syndrome; COVID-19; Comorbidity; Intensive care unit; Severity
    DOI:  https://doi.org/10.3947/ic.2020.0136
  3. BMC Public Health. 2021 08 16. 21(1): 1554
       BACKGROUND: Smoking impairs lung immune function and damages upper airways, increasing risks of contracting and severity of infectious diseases. This paper quantifies the association between smoking and COVID-19 disease progression.
    METHODS: We searched PubMed and Embase for studies published from January 1-May 25, 2020. We included studies reporting smoking behavior of COVID-19 patients and progression of disease, including death. We used random effects meta-analysis, meta-regression and locally weighted regression and smoothing to examine relationships in the data.
    RESULTS: We identified 46 peer-reviewed papers with a total of 22,939 COVID-19 patients, 5421 (23.6%) experienced disease progression and 2914 (12.7%) with a history of smoking (current and former smokers). Among those with a history of smoking, 33.5% experienced disease progression, compared with 21.9% of non-smokers. The meta-analysis confirmed an association between ever smoking and COVID-19 progression (OR 1.59, 95% CI 1.33-1.89, p = 0.001). Ever smoking was associated with increased risk of death from COVID-19 (OR 1.19, 95% CI 1.02-1.39, p = 0.003). We found no significant difference (p = 0.864) between the effects of ever smoking on COVID-19 disease progression between adjusted and unadjusted analyses, suggesting that smoking is an independent risk factor for COVID-19 disease progression. We also found the risk of having COVID-19 progression higher among younger adults (p = 0.001), with the effect most pronounced among younger adults under about 45 years old.
    CONCLUSIONS: Smoking is an independent risk for having progression of COVID-19, including mortality. The effects seem to be higher among young people. Smoking prevention and cessation should remain a priority for the public, physicians, and public health professionals during the COVID-19 pandemic.
    Keywords:  Age effect; COVID-19; Coronavirus; Death; Disease progression; Meta-analysis; Odds ratio
    DOI:  https://doi.org/10.1186/s12889-021-11579-x