Comorbidities

exp date isn't null, but text field is

Atrial fibrillation

Increased risk of COVID-19-related hospitalisation or death: relative effect >1 to <2

Evidence

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital
admissions found that atrial fibrillation was significantly associated with contracting COVID-19 and subsequent hospitalisation and death.25

Cancer

Increased risk of COVID-19-related hospitalisation or death: relative effect ≥2 

Evidence

A study of 10,926 deaths due to COVID-19 in England distinguished haematological and non-haematological cancer and time since diagnosis. Death due to COVID-19 was significantly associated with both types of cancer. For recently diagnosed haematological cancer the HR was 2.80 (95% CI 2.08 to 3.78) reducing to 1.61 (95% CI 1.39 to 1.87) if diagnosed more than five years previously. For non-haematological cancers the HR was 1.72 (95% CI 1.50 to 1.96) for cancer diagnosed within a year reducing to a risk equivalent to that of individuals without cancer, for cancers diagnosed more than five years previously.11 

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital admissions found that blood cancer was significantly associated with contracting COVID-19 and subsequent hospitalisation and death. The same study found that respiratory tract cancer was significantly associated with hospitalisation in men and women and death in women. Any chemotherapy in the last 12 months or radiotherapy in the last 6 months were significantly associated with both death and hospitalisation for both sexes.29 

A prospective cohort study from the UK Coronavirus Cancer Monitoring Project (UKCCMP) which included 800 patients admitted to hospital over a 5-week period with a diagnosis of cancer and symptomatic COVID-19 reported that 226 patients (28%) died. Risk of death was significantly associated with older patient age (OR 9.42, 95% CI 6.56 to 10.02), male sex (OR 1.67, 95% CI 1.19 to 2.34) and the presence of other comorbidities such as hypertension (OR 1.95, 95% CI 1.36 to 2.80) and cardiovascular disease (OR 2.32, 95% CI 1.47 to 3.64). After adjusting for age, gender, and comorbidities, chemotherapy in the previous 4 weeks was not significantly associated with mortality from COVID-19 disease compared with patients with cancer who had not received recent chemotherapy (OR 1.18, 95% CI 0.81 to 1.72). There was no statistically significant effect on mortality for patients who received immunotherapy, hormone therapy, targeted treatment or radiotherapy within the previous four weeks.71

Another study from the UKCCMP explored the effect of tumour subtype on COVID-19 outcomes in patients with cancer (n=1,044) by comparing the cohort with the profile of a non-COVID-19 UK cancer control population (from 2017). Some tumour subtypes were over-represented in the UKCCMP patient cohort compared with the control population. Patients with haematological malignancies (leukaemia, myeloma, and lymphoma) were at significantly increased risk of COVID-19 infection. Patients with lung cancer and prostate cancer were relatively underrepresented in the COVID-19 cohort. When compared with cancers of the digestive organs, which had the median case fatality rate, patients with leukaemia had a significantly increased case fatality rate (OR 2.25, 95% CI 1.13 to 4.57, p=0·023). There was no evidence of increased case fatality rate due to COVID-19 in patients with lung cancer compared with the rest of the UKCCMP population (OR 1.41, 95% CI 0.75 to 2.67, p=0.29).72 When the effects of cancer control status in COVID-19 patients with haematological cancers was analysed (n=527) those with an indication to ”give first treatment now” had a greater risk of all-cause death when compared with asymptomatic patients on active surveillance (OR 2.45, 95% CI 1.09 to 5.5, p=0.03). There was also an increased risk for patients who had been treated and had progressive or relapsed disease (OR 3.21, 95% CI 1.68 to 6.14, p<0.001).73

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with death due to COVID-19 and hospital admission as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, the cause-specific HR for death due to COVID-19 in patients with blood cancer was 1.42 (95% CI 1.09 to 1.85) and 1.65 (95% CI 1.13 to 2.39) for those with respiratory tract cancer.35  

Chronic kidney disease

Increased risk of COVID-19-related hospitalisation or death: relative effect ≥2 

Evidence

An observational study of 10,926 deaths due to COVID-19 in England found a significant association with chronic kidney disease (CKD). The study distinguished between estimated glomerular filtration rate (eGFR) 30–60, HR 1.33 (95% CI 1.28 to 1.40) and eGFR <30, HR 2.52 (95% CI 2.33 to 2.72).11

A case-control study of 4,272 severe COVID-19 cases and 36,948 controls in Scotland found that severe disease was significantly associated with chronic kidney disease or being a transplant recipient (RR 2.88, 95% CI 2.13 to 3.89).33 

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with death due to COVID-19 and hospital admission as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, the cause- specific COVID-19 hospital admission rate in patients with CKD was increased compared with those with no kidney disease. The increase was seen for patients with stage 3 CKD (HR 1.3, 95% CI 1.17 to 1.45), stage 4 CKD (HR 1.73, 95% CI 1.32 to 2.28), stage 5 CKD (HR 2.23, 95% CI 1.52 to 3.28), dialysis (HR 7.37, 95% CI 3.95 to 13.77) and transplantation (HR 12.82, 95% CI 7.65 to 21.47). A similar pattern was observed with death due to COVID-19. Patients on dialysis and those with kidney transplantation were amongst the groups with the highest hazard ratios for severe COVID-19 in this study.35 

A prospective cohort study linked vaccination status, primary care records, COVID-19 testing, hospitalisation and mortality data in Scotland to assess the frequency of adverse COVID-19 outcomes in people receiving at least one vaccine dose. Data from December 2020 to April 2021 were included. Having CKD (stage 3–5) was associated with increased risk of the composite outcome of COVID-19-related hospitalisation or death (RR 1.60, 95% CI 1.39 to 1.84).45 

 

Chronic liver disease

Increased risk of COVID-19-related hospitalisation or death: relative effect ≥2 

Evidence

An observational study of 10,926 deaths due to COVID-19 in England found that death due to COVID-19 was significantly associated with chronic liver disease (HR 1.75, 95% CI 1.51 to 2.03).11

A case-control study of 4,272 severe COVID-19 cases and 36,948 controls in Scotland found that severe disease was significantly associated with liver disease (RR 1.93, 95% CI 1.32 to 2.81).33 

A propensity score matched analysis in patients with COVID-19 in a UK based chronic liver disease registry (n=184) provided estimates of the risk of death for each disease stage; chronic liver disease without cirrhosis 4.4% (95% CI -6.9% to 15.8%; p=0.445), Child-Pugh A 8.5% (95% CI -9.2 to 26.2, p=0.349), Child-Pugh B 17.8% (95% CI 2.5 to 33.1%, p=0.023), and Child-Pugh C 50.5% (95% CI 28.1% to 72.8%, p ≤0.001).70 

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with death due to COVID-19 and hospital admission as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, the cause-specific COVID-19 hospital admission rate in patients with liver cirrhosis was increased compared with those with no liver cirrhosis (HR 1.79, 95% CI 1.13 to 2.83). Cause-specific COVID-19-related death was also increased (HR 2.96, 95% CI 2.02 to 4.34).35

A prospective cohort study linked vaccination status, primary care records, COVID-19 testing, hospitalisation and mortality data in Scotland to assess the frequency of adverse COVID-19 outcomes in people receiving at least one vaccine dose. Data from December 2020 to April 2021 were included. Having liver cirrhosis was associated with increased risk of the composite outcome of COVID-19-related hospitalisation or death (RR 1.49, 95% CI 0.87 to 2.36). This was not statistically significant.45 

Chronic respiratory disease

Increased risk of COVID-19-related hospitalisation or death: relative effect >1 to <2 for asthma and chronic obstructive pulmonary disease

Evidence

A population-based cohort study using data from the UK Biobank (n=492,768) reported that adults with asthma had a higher risk of severe COVID-19, which was driven by the increased risk in patients with nonallergic asthma (OR 1.48, 95% CI 1.15 to 1.92). In contrast, the risk of severe COVID-19 was not significantly elevated in patients with allergic asthma (OR 1.29, 95% CI 0.96 to 1.74).76 

A population-based cohort study using data from 1,205 general practices in England examined the association between pre-existing respiratory disease and outcomes related to severe COVID-19. People with chronic obstructive pulmonary disease (COPD) had an increased risk of hospital admission (HR 1.54, 95% CI 1.45 to 1.63), and death due to COVID-19 (HR 1.54, 95% CI 1.4 to 1.63). Admission to ICU was rare across the cohort. For people with COPD there was no strong evidence of increased risk of ICU admission compared to the overall cohort (HR 0.89, 95% CI 0.68 to 1.17). People with active asthma (HR 1.18, 95% CI 1.13 to 1.24) and severe asthma (HR 1.29, 95% CI 1.22 to 1.37) had an increased risk of hospitalisation but no evidence of increased risk of death due to COVID-19; active asthma (HR 1.05, 95% CI 0.91 to 1.15), severe asthma (HR 1.08, 95% CI 0.98 to 1.19). Severe asthma was associated with increased risk of ICU admission (HR 1.30, 95% CI 1.08 to 1.58).77 

A study of UK patients admitted to hospital (n=75,463) explored the association between COVID-19 mortality, underlying respiratory comorbidity (asthma or chronic pulmonary disease) and treatments. In patients aged over 50 with asthma those using inhaled corticosteroids (ICS) had a reduced risk of mortality compared to patients without respiratory disease (HR 0.86, 95% CI 0.80 to 0.92) whilst asthma patients in this group not using ICS had a risk of in-hospital mortality which was not different to those without respiratory disease (HR 0.97, 95% CI 0.89 to 1.05). For patients aged over 50 with chronic pulmonary disease both those not using ICS (HR 1.16, 95% CI 1.12 to 1.22) and those using ICS (HR 1.10, 95% CI 1.04 to 1.16) had a significantly increased risk of in-hospital mortality when compared with those without respiratory disease.78 

A prospective cohort study linked vaccination status, primary care records, COVID-19 testing, hospitalisation and mortality data in Scotland to assess the frequency of adverse COVID-19 outcomes in people receiving at least one vaccine dose. Data from December 2020 to April 2021 were included. Having asthma was associated with increased risk of the composite outcome of COVID-19-related hospitalisation or death (RR 1.19, 95% CI 1.01 to 1.40).45 

Congenital heart disease

Risk may depend on physiological consequences of the abnormality

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital admissions found no evidence that congenital heart disease as an independent risk factor was associated with contracting COVID-19 and subsequent hospitalisation and death for either men or women.25 

Congestive heart failure

Increased risk of COVID-19-related hospitalisation or death: relative effect >1 to <2

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital admissions found that congestive heart failure was significantly associated with contracting COVID-19 and subsequent hospitalisation and death for both men and women.25 

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with death due to COVID-19 and hospital admission as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, the cause-specific COVID-19 hospital admission rate in patients with heart failure was increased compared with those with no heart failure (HR 1.37, 95% CI 1.18 to 1.60). Cause-specific COVID-19-related death was also increased (HR 1.43, 95% CI 1.25 to 1.63).35 

A prospective cohort study linked vaccination status, primary care records, COVID-19 testing, hospitalisation and mortality data in Scotland to assess the frequency of adverse COVID-19 outcomes in people receiving at least one vaccine dose. Data from December 2020 to April 2021 were included. Having heart failure was associated with increased risk of the composite outcome of COVID-19-related hospitalisation or death (RR 1.69, 95% CI 1.35 to 2.08).45 

Coronary heart disease

Increased risk of COVID-19-related hospitalisation or death: relative effect >1 to <2

An observational study of 10,926 deaths due to COVID-19 in England found that death due to COVID-19 was significantly associated with chronic heart disease (hazard ratio (HR) 1.17, 95% CI 1.12 to 1.22).11 

A case-control study of 4,272 severe COVID-19 cases and 36,948 controls in Scotland found that severe disease was significantly associated with other heart disease (RR 1.33, 95% CI 1.23 to 1.46) but not with ischaemic heart disease (relative risk (RR) 1.08, 95% CI 0.98 to 1.20).33  

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital admissions found that coronary heart disease was significantly associated with death for both men and women but hospitalisation only for women.25  

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with death due to COVID-19 and hospital admission as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, the cause-specific COVID-19 hospital admission rate in patients with coronary heart disease was increased compared with those with no coronary heart disease (HR 1.30, 95% CI 1.16 to 1.46). Cause-specific COVID-19-related death was also increased (HR 1.18, 95% CI 1.07 to 1.32).35 

A prospective cohort study linked vaccination status, primary care records, COVID-19 testing, hospitalisation and mortality data in Scotland to assess the frequency of adverse COVID-19 outcomes in people receiving at least one vaccine dose. Data from December 2020 to April 2021 were included. Having coronary heart disease was associated with increased risk of the composite outcome of COVID-19-related hospitalisation or death (RR 1.51, 95% CI 1.31 to 1.73). 45  

Diabetes

Increased risk of COVID-19-related hospitalisation or death: relative effect ≥2 

Evidence

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital admissions found that both type 1 and type 2 diabetes were significantly associated with COVID-19-related death. The HR for death in women with type 1 diabetes was 4.02 (95% CI 2.07 to 7.82) whilst for type 2 diabetes it was 6.29 (95% CI 4.08 to 9.70). A similar pattern of findings was reported for death in men and for COVID-19-related hospital admissions in both sexes.25  

An observational study of 10,926 deaths due to COVID-19 in England distinguished diabetes with glycated haemoglobin (HbA1c) above and below 58 mmol/mol and diabetes with no recent measure. It found that death due to COVID-19 was significantly associated with all diabetes with those patients with HbA1c below 58 mmol/mol having the lowest risk (HR 1.31, 95% CI 1.24 to 1.37). Those with HbA1c equal to or above 58 mmol/mol had a HR of 1.95 (95% CI 1.83 to 2.08) and those without a recent measurement HR 1.90 (95% CI 1.72 to 2.09).11  

A case-control study of 4,272 severe COVID-19 cases and 36,948 controls in Scotland found that severe disease was significantly associated with both type 1 (RR 1.56, 95% CI 1.05 to 2.32) and type 2 diabetes (RR 1.42, 95% CI 1.29 to 1.56).33 

A population level cohort study in England (n= 61,414,470) identified inhospital deaths with COVID-19 and examined the association with type 1 and type 2 diabetes. When adjusted for age, sex, deprivation and some comorbidities both type 1 and type 2 diabetes were associated with significantly greater odds of death due to COVID-19 (OR 2.86, 95% CI 2.58 to 3.8 and OR 1.80, 95% CI 1.75 to 1.86, respectively).66 

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with death due to COVID-19 and hospital admission as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, the cause-specific COVID-19 hospital admission rate in patients with type 2 diabetes and HbA1c ≥59 mmol/mol increased compared with those with no type 2 diabetes (HR 1.76, 95% CI 1.50 to 2.05). Cause-specific COVID-19- related death was also increased (HR 1.43, 95% CI 1.21 to 1.70). A similar pattern was seen for those with HbA1c <59 mmol/mol.35 

A prospective cohort study linked vaccination status, primary care records, COVID-19 testing, hospitalisation and mortality data in Scotland to assess the frequency of adverse COVID-19 outcomes in people receiving at least one vaccine dose. Data from December 2020 to April 2021 were included. Having diabetes was associated with increased risk of the composite outcome of COVID-19-related hospitalisation or death, for type 2 diabetes (RR 1.81, 95%CI 1.58 to 2.07), and type 1 diabetes (RR 1.26, 95% CI 0.54 to 2.44) respectively. The association was not statistically significant for type 1 diabetes.45 

Frailty

Increased risk of COVID-19-related hospitalisation or death: relative effect ≥2 

Evidence

A retrospective comparative cohort study explored the association between frailty in UK Biobank participants (n=383,845) and severe COVID-19 leading to hospitalisation or death between March 2020 and June 2020. Adjustments were made for sociodemographic factors such as age and gender and lifestyle factors including smoking and alcohol intake. When compared with participants whose physiological status was measured as robust, mild frailty and moderate/severe frailty were associated with greater risk of adverse COVID-19 outcomes (RR 1.46, 95% CI 1.26 to 1.71 and RR 2.43, 95% CI 1.91 to 3.10, respectively).74  

A cohort study conducted at ten hospitals in the UK and one in Italy found that the OR for day-7 mortality for patients with a clinical frailty score of 7–9 where a score of 5 or more indicates frailty and 9 indicates patients are terminally ill (compared to a score of 1–2) was 3.12 (95% CI 1.56 to 6.24).75 

Hypertension

Conflicting evidence depending on level of blood pressure control

A large observational study of 10,926 deaths due to COVID-19 in England found that death due to COVID-19 was negatively associated with high blood pressure or diagnosed hypertension (HR 0.89, 95% CI 0.85 to 0.93). A post-hoc analysis indicated that hypertension was associated with a higher risk of COVID-19-related death up to the age of 70 years and a lower risk above the age of 70.11  

A retrospective cohort study conducted in the first phase of the pandemic (January 2020 to August 2020) examined the risk of COVID-19-related death in people according to their blood pressure control. When adjusting for all known covariates individuals with stage 1 uncontrolled hypertension had a lower risk of COVID-19-related death when compared to those with well-controlled blood pressure (OR 0.76, 95% CI 0.62 to 0.92). For participants with moderately raised blood pressure and stage 2 or above uncontrolled blood pressure there was no evidence of any significant association with COVID-19-related death.48 

Immunosuppressive conditions

Increased risk of COVID-19-related hospitalisation or death: relative effect ≥2 for HIV/AIDS

Evidence

A case-control study of 4,272 severe COVID-19 cases and 36,948 controls in Scotland found that severe disease was significantly associated with immune deficiency or suppression (RR 1.67, 95% CI 1.10 to 2.52).33 

A population-based retrospective analysis in the UK reported that, when adjusted for age, sex, ethnicity, deprivation and selected comorbidities, people living with human immunodeficiency virus (HIV) (n=27,480) were at greater risk of COVID-19-related death than people who did not have HIV (n=17,282,905) (HR 2.30, 95% CI 1.55 to 3.41).67 

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with COVID-19-related death as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, cause-specific COVID-19-related death in patients with HIV/acquired immune deficiency syndrome (AIDS) was increased compared with those with no HIV/AIDS (HR 3.29, 95% CI 1.05 to 10.29). Severe combined immunodeficiency was not statistically significantly associated with COVID-19-related mortality (HR 1.31, 95% CI 0.33 to 5.27). In this study COVID-19-related mortality was increased for patients receiving grade B chemotherapy (HR 3.63, 95% CI 2.57 to 5.12) and grade C chemotherapy (HR 4.30, 95% CI 1.06 to 17.51).35 

Outcomes for people with COVID-19 and an immunosuppressive condition may be impacted by the pharmacological therapies used to manage their condition.31 Some immunosuppressive conditions and therapies may be associated with reduced vaccine effectiveness (see section 5). 

Inflammatory bowel disease

No additional risk of COVID-19-related hospitalisation or death

Evidence

In a multinational cohort of consecutive patients with COVID-19 attending specialist inflammatory bowel disease centres between February 2020 and June 2020 (n=17 UK) the authors concluded that the risk of COVID19 mortality for patients with inflammatory bowel disease was similar to that for the general population.81  

Learning disabilities

Increased risk of COVID-19-related hospitalisation or death: relative effect ≥2 for learning disabilities, including Down’s Syndrome

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital admissions found that learning disabilities were associated with contracting COVID-19 and subsequent hospitalisation and death for both men and women. The risk of death for individuals with Down’s Syndrome was found to be high compared to those without any learning disabilities; HR for death in men 9.8 (95% CI 4.62 to 20.78), and in women OR 32.55 (95% CI 18.13 to 58.42).25,63 

A follow-up study in vaccinated individuals similarly reported that for people with Down’s Syndrome the condition specific hazard ratio for death due to COVID-19 was 12.68 (95% CI 4.68 to 34.38). For COVID19 hospital admission the condition specific HR was 2.55 (95% CI 0.63 to 10.28).35 

A population-based cohort study provided data on the association between being on the GP learning disability register in NHS England and COVID-19 outcomes during the second wave of the pandemic (September 2020 to February 2021). When compared with adults not on the register there was an increased risk of COVID-19-related hospital admission (HR 4.32, 95% CI 4.05 to 4.61) and death (HR 7.22, 95% CI 6.41 to 8.13). Associations were greatest for those whose disability was classed as severe to profound and those in residential care. Children (<16 years) on the register had an increased risk of COVID-19-related hospital admission (HR 9.18, 95% CI 5.89 to 14.29). There were insufficient data to analyse the effects on COVID-related deaths in children.64

 

Multimorbidity

Increased risk of COVID-19-related hospitalisation or death: relative effect ≥2 

Evidence

A UK retrospective cohort study (n=2,217) examined the association between number of comorbidities and COVID-19-related death in hospitalised patients during the first phase of the pandemic (March to May 2020). When compared with no comorbidities, having 1–2 comorbid conditions increased the risk of death (HR 1.7, 95% CI 1.3 to 2.2) as did having three or more comorbid conditions (HR 2.3, 95% CI 1.7 to 3.0).61 

A retrospective single cohort study provided Scottish data on the risk of death with COVID-19 in double vaccinated people who received their positive test in the community (n=53 deaths). When adjusted for age, sex and deprivation, those with 3–4 comorbidities (HR 4.75, 95% CI 1.69 to 13.39) or >5 comorbidities had increased risk of death when compared to those with no comorbidities (HR 10.01, 95% CI 3.15 to 31.79).62 

In a retrospective cohort study using UK Biobank data (n= 360,283) people with multimorbidity (two or more conditions) were more likely to be admitted with severe COVID-19 when compared with those with no recorded comorbidity (OR 1.91, 95% CI 1.70 to 2.15). Diagnostic clusters containing asthma and hypertension had the lowest risk (OR 1.29, 95% CI 1.03 to 1.60) and those containing chronic kidney disease and diabetes were associated with the highest risk (OR 4.93, 95% CI 3.36 to 7.22).32 

A prospective cohort study linked vaccination status, primary care records, COVID-19 testing, hospitalisation and mortality data in Scotland to assess the frequency of adverse COVID-19 outcomes in people receiving at least one vaccine dose. Data from December 2020 to April 2021 were included. Multimorbidity (including care home residence) was associated with increased risk of the composite outcome of COVID-19-related hospitalisation or death. When compared with people with no comorbidities, those having five or more comorbidities had RR 4.24 (95% CI 3.34 to 5.39).45 

Neurological conditions

Increased risk of COVID-19-related hospitalisation or death: relative effect ≥2

An observational study of 10,926 deaths due to COVID-19 in England found that death due to COVID-19 was significantly associated with stroke or dementia (HR 2.16, 95% CI 2.06 to 2.27) and other neurological conditions (HR 2.58, 95% CI 2.38 to 2.79).11 

A case-control study of 4,272 severe COVID-19 cases and 36,948 controls in Scotland found that severe disease was significantly associated with neurological conditions (except epilepsy) or dementia (RR 2.00, 95% CI 1.81 to 2.21).33 

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital admissions found that dementia, epilepsy and cerebral palsy were significantly associated with contracting COVID-19 and subsequent hospitalisation and death for men and women. Parkinson’s Disease was significantly associated with hospitalisation for both sexes but only with death for men.25 

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with death due to COVID-19 and hospital admission as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, the cause-specific COVID-19 hospital admission rate in patients was increased for those with dementia (HR 2.07, 95% CI 1.79 to 2.39), Parkinson’s disease (HR 1.47, 95% CI 1.06 to 2.03), epilepsy (HR 1.70, 95% CI 1.32 to 2.20), and rare neurological conditions (HR 2.30, 95% CI 1.44 to 3.65). Rare neurological conditions encompassed motor neurone disease, multiple sclerosis, myasthenia gravis, or Huntington’s disease. A similar pattern was observed with death due to COVID-19 where there was a statistically significant increase when compared to people without neurological conditions for all groups except those with epilepsy (HR 1.13, 95% CI 0.85 to 1.50).35 

A prospective cohort study linked vaccination status, primary care records, COVID-19 testing, hospitalisation and mortality data in Scotland to assess the frequency of adverse COVID-19 outcomes in people receiving at least one vaccine dose. Data from December 2020 to April 2021 were included. Having a chronic neurological conditions was associated with increased risk of the composite outcome of COVID-19-related hospitalisation or death (RR 1.27, 95% CI 0.58 to 2.37). This was not statistically significant. Having dementia was associated with increased risk of the composite outcome of COVID-19-related hospitalisation or death (RR 5.32, 95% CI 4.57 to 6.18).45 

Peripheral vascular disease

Increased risk of COVID-19-related hospitalisation or death: relative effect >1 to <2

Evidence

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital admissions found that peripheral vascular disease was significantly associated with contracting COVID-19 and subsequent hospitalisation and death for both men and women.25 

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with death due to COVID-19 and hospital admission as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, the cause-specific COVID-19 hospital admission rate in patients with peripheral vascular disease was increased (not statistically significant) compared with those with no peripheral vascular disease (HR 1.20, 95% CI 0.97 to 1.48). Cause-specific COVID-19-related death was also increased (HR 1.31, 95% CI 1.09 to 1.57).35 

 

Previous history of COVID-19

Reduced risk of COVID-19-related hospitalisation or death

Evidence

A prospective cohort study linked vaccination status, primary care records, COVID-19 testing, hospitalisation and mortality data in Scotland to assess the frequency of adverse COVID-19 outcomes in people receiving at least one vaccine dose. Data from December 2020 to April 2021 were included. Having a previous history of COVID-19 infection was associated with reduced risk of the composite outcome of COVID-19- related hospitalisation or death (RR 0.40, 95% CI 0.29 to 0.54). 45 

Obesity

Increased risk of COVID-19-related hospitalisation or death: relative effect >1 to <2

Evidence

An observational study of 10,926 deaths due to COVID-19 in England found that death due to COVID-19 was significantly associated with obesity. The HR for BMI of 30–34.9 kg/m2 was 1.05 (95% CI 1.00 to 1.11), 35–39.9 was 1.40 (95% CI 1.30 to 1.52) and 40 kg/m2 or over was 1.92 (95% CI 1.72 to 2.13) all compared with BMI <30 kg/m2.11

A prospective cohort study (n=6,910,695) conducted using English GP practice data explored the association between last recorded BMI and hospital admission, ICU admission and death related to COVID-19. This study examined the full range of BMI rather than focusing on obesity (BMI >30). When adjusted for confounders including age, sex, socioeconomic status, comorbidities and ethnicity each excess BMI unit above a BMI of 23 kg/m2 was associated with increased risk of hospital admission (HR 1.05, 95% CI 1.05 to 1.05), ICU admission (HR 1.10, 95% CI 1.09 to 1.10), and death (HR 1.04, 95% CI 1.04 to 1.05). There was a statistically significant interaction between BMI and age and ethnicity, with higher HR per kg/m2 above BMI 23 kg/m2 for younger people (age 20–39) compared with older people (age 80-100) and black people when compared with white people. The authors concluded that even a small increase in BMI above 23 kg/m2 is a risk factor for adverse COVID-19 outcomes.79 

A UK prospective study using hospital admission data (n=65,932) from February 2020 to October 2020 explored the impact of obesity on COVID-19 outcomes, including ICU admission, ventilation, and death. Obesity (objectively measured or by clinical opinion) was consistently associated with admission to critical care, mechanical ventilation, and mortality in all ethnic groups. For all outcomes, the association with obesity was strongest in black ethnicities. For example, in white ethnicities, the OR for mortality in those with obesity compared with those without obesity was OR 1.23 (95% CI 1.15 to 1.32) whereas it was OR 1.98 (95% CI 1.46 to 2.68) for black ethnicities.58 

Rheumatic diseases

Increased risk of COVID-19-related hospitalisation or death: relative effect >1 to <2 for rheumatoid arthritis, psoriatic arthritis and systemic lupus erythematosus

Evidence

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital admissions found that rheumatoid arthritis (RA) and systematic lupus erythematosus were significantly associated with contracting COVID-19 and subsequent hospitalisation for both sexes and death for women.25 

An observational study of 10,926 deaths in England found that death related to COVID-19 was significantly associated with rheumatoid arthritis, psoriatic arthritis or lupus (HR 1.19, 95% CI 1.11 to 1.27).11  

A case-control study used UK Biobank data to compare COVID-19 outcomes for people with RA (n=5,409) and people without RA (n=467,730). For people diagnosed with COVID-19, RA was associated with increased risk of death when adjusted for other conditions (OR 1.89, 95% CI 1.19 to 3.02). 80  

Severe mental illness

Increased risk of COVID-19-related hospitalisation or death: relative effect ≥2

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital admissions found that severe mental illness was associated with contracting COVID-19 and subsequent hospitalisation (HR 1.37, 95% CI 1.28 to 1.47) and death in women (HR 1.29, 95% CI 1.15 to 1.45). Data for men were similar.25 

A UK Biobank cohort study conducted during the first phase of the pandemic (January 2020 to July 2020) explored the association between prepandemic psychiatric diagnoses (recorded between 2006 and 2010) and COVID-19 outcomes. When adjusted for age, sex, ethnicity, socioeconomic factors and chronic diseases those with a psychiatric diagnosis had increased risk of COVID-19 hospitalisation (OR 1.55, 95% CI 1.34 to 1.78) and COVID-19-related death (OR 2.03, 95% CI 1.59 to 2.59). Odds ratios were highest for psychotic disorders but small numbers led to uncertainty around estimates.68 

A matched case-control study (n=4,251 cases, 36,738 controls) conducted in Scotland examined the association between polypharmacy and severe COVID-19 defined as admission to critical care or death. Severe COVID-19 was strongly associated with the increasing number of non-cardiovascular drug classes dispensed. There was a large effect estimate for patients prescribed antipsychotic agents compared with those prescribed non-antipsychotic agents (RR 2.80, 95% CI 2.24 to 3.51).69 

Sickle cell disease

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital
admissions found that sickle cell disease was significantly associated with COVID-19-related hospitalisation and death for both sexes.25

A similar but more recent study also found that that sickle cell disease was associated with increased risk of both COVID-19-related hospitalisation (HR 4.11, 95% CI 2.98 to 5.66) and COVID-19-related death (HR 2.55, 95% CI 1.36 to 4.75).65  

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with COVID-19-related death as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, cause-specific COVID-19-related death in patients with sickle cell disease was increased compared with those with no sickle cell disease (HR 7.73, 95% CI 1.07 to 55.83).35 

Stroke

Increased risk of COVID-19-related hospitalisation or death: relative effect >1 to <2

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with death due to COVID-19 and hospital admission as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, the cause-specific COVID-19 hospital admission rate in patients with stroke was increased compared with those with no stroke (HR 1.15, 95% CI 1.01 to 1.32). Cause-specific COVID-19-related death was also increased (HR 1.21, 95% CI 1.08 to 1.36).35 

Thromboembolism

Increased risk of COVID-19-related hospitalisation or death: relative effect >1 to <2

A population-based cohort study using primary care data from over 6 million patients in the UK with 4,384 deaths and 10,776 hospital admissions found that thromboembolism was significantly associated with contracting COVID-19 and subsequent hospitalisation or death for both men and women (HR 1.18, 95% CI 1.01 to 1.38).25  

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with death due to COVID-19 and hospital admission as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, the cause-specific COVID-19 hospital admission rate in patients with history of venous thromboembolism (VTE) was not significantly increased when compared with those with no prior VTE (HR 1.13, 95% CI 0.95 to 1.34). Cause-specific COVID-19-related death was increased (HR 1.45, 95% CI 1.26 to 1.67).35 

Transplants

Increased risk of COVID-19-related hospitalisation or death: relative effect ≥2

Evidence

A large observational study of 10,926 deaths due to COVID-19 in England found that death due to COVID-19 was significantly associated with organ transplant (HR 3.53, 95% CI 2.77 to 4.49).11 

A case-control study of 4,272 severe COVID-19 cases and 36,948 controls in Scotland found that severe disease was significantly associated with chronic kidney disease or being a transplant recipient (RR 2.88, 95% CI 2.13 to 3.89).33 

A prospective cohort study of vaccinated people (74% had two vaccine doses) in England explored variables associated with death due to COVID-19 and hospital admission as a derivation dataset to develop a risk prediction algorithm (QCovid3). When adjusted for factors including age, BMI, deprivation and background infection level, the cause-specific COVID-19 hospital admission rate in patients with recent bone marrow or solid organ transplantation ever increased compared with those with no transplant (HR 6.81, 95% CI 3.18 to 14.56). Cause-specific COVID-19- related death was also increased although there was low certainty around the estimate consistent with a lower or higher mortality rate (HR 2.49, 95% CI 0.62 to 10.08).35