Pre-existing health conditions and severe COVID-19 outcomes: an umbrella review approach and meta-analysis of global evidence.

BACKGROUND: This study applies an umbrella review approach to summarise the global evidence on the risk of severe COVID-19 outcomes in patients with pre-existing health conditions. METHODS: Systematic reviews (SRs) were identified in PubMed, Embase/Medline and seven pre-print servers until December 11, 2020. Due to the absence of age-adjusted risk effects stratified by geographical regions, a re-analysis of the evidence was conducted. Primary studies were extracted from SRs and evaluated for inclusion in the re-analysis. Studies were included if they reported risk estimates (odds ratio (OR), hazard ratio (HR), relative risk (RR)) for hospitalisation, intensive care unit admission, intubation or death. Estimated associations were extracted from the primary studies for reported pre-existing conditions. Meta-analyses were performed stratified for each outcome by regions of the World Health Organization. The evidence certainty was assessed using GRADE. Registration number CRD42020215846. RESULTS: In total, 160 primary studies from 120 SRs contributed 464 estimates for 42 pre-existing conditions. Most studies were conducted in North America, European, and Western Pacific regions. Evidence from Africa, South/Latin America, and the Eastern Mediterranean region was scarce. No evidence was available from the South-East Asia region. Diabetes (HR range 1.2-2.0 (CI range 1.1-2.8)), obesity (OR range 1.5-1.75 (CI range 1.1-2.3)), heart failure (HR range 1.3-3.3 (CI range 0.9-8.2)), COPD (HR range 1.12-2.2 (CI range 1.1-3.2)) and dementia (HR range 1.4-7.7 (CI range 1.2-39.6)) were associated with fatal COVID-19 in different regions, although the estimates varied. Evidence from Europe and North America showed that liver cirrhosis (OR range 3.2-5.9 (CI range 0.9-27.7)) and active cancer (OR range 1.6-4.7 (CI range 0.5-14.9)) were also associated with increased risk of death. Association between HIV and undesirable COVID-19 outcomes showed regional heterogeneity, with an increased risk of death in Africa (HR 1.7 (CI 1.3-2.2)). GRADE certainty was moderate to high for most associations. CONCLUSION: Risk of undesirable COVID-19 health outcomes is consistently increased in certain patient subgroups across geographical regions, showing high variability in others. The results can be used to inform COVID-19 vaccine prioritisation or other intervention strategies.

Condition-specific mortality risk can explain differences in COVID-19 case fatality ratios around the globe.

OBJECTIVES: With COVID-19 infections resulting in death according to a hierarchy of risks, with age and pre-existing health conditions enhancing disease severity, the objective of this study is to estimate the condition-specific case fatality ratio (CFR) for different subpopulations in Italy. STUDY DESIGN: The design of the study was to estimate the 'pre-existing comorbidity'-conditional CFR to eventually explain the mortality risk variability reported around in different countries. METHODS: We use the available information on pre-existing health conditions identified for deceased patients 'positive with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)' in Italy. We (i) estimated the total number of deaths for different pre-existing health conditions categories and (ii) calculated a conditional CFR based upon the number of comorbidities before SARS-CoV-2 infection. RESULTS: Our results show a 0.6% conditional CFR for a population with zero pre-existing pathology, increasing to 13.9% for a population diagnosed with one and more pre-existing health conditions. CONCLUSIONS: Condition-specific mortality risks are important to be evaluated during the COVID-19 pandemic, with potential elements to explain the CFR variability around the globe. A careful postmortem examination of deceased cases to differentiate death 'caused by COVID-19' from death 'positive with SARS-CoV-2' is therefore urgently needed and will likely improve our understanding of the COVID-19 mortality risk and virus pathogenicity.

Health Literacy and Preventive Behaviors Modify the Association between Pre-Existing Health Conditions and Suspected COVID-19 Symptoms: A Multi-Institutional Survey.

People with pre-existing health conditions (PEHC) are vulnerable to viral infection while health literacy (HL) and preventive behaviors (PB) have been shown to benefit people during the COVID-19 pandemic. The aim of this study was to examine the association between PEHC and suspected COVID-19 symptoms (S-COVID-19-S), and to investigate the modification effect of HL and PB. A cross-sectional study was conducted on 8291 participants visiting outpatient departments at 18 hospitals and health centers across Vietnam from 14 February to 31 May 2020. Data were collected regarding participant's characteristics, HL, PB, PEHC, and S-COVID-19-S. Regression models were used for analyzing the associations. Results showed that people with PEHC had a 3.38 times higher likelihood of having S-COVID-19-S (odds ratio, OR, 3.38; 95% confidence interval, 95% CI, 3.01, 3.79; p < 0.001). In comparison to participants without PEHC and with the lowest HL score, those with PEHC and one HL score increment had a 7% lower likelihood of having S-COVID-19-S (OR, 0.93; 95% CI, 0.92, 0.94; p < 0.001). In comparison to participants without PEHC and not adhering to mask wearing, those with PEHC and adhering to mask wearing had a 77% lower likelihood of having S-COVID-19-S (OR, 0.23; 95% CI, 0.16, 0.32; p < 0.001). Higher HL and adherence to mask wearing can protect people from having S-COVID-19-S, especially in those with PEHC.