Underlying Health Conditions 

According to the NHS in the UK the underlying health conditions that increase the risk of a severe outcome of Covid-19 are:

High Risk (clinically extremely vulnerable)

People at high risk of a severe outcome from COVID-19 include those who:

  • have had an organ transplant

  • are having chemotherapy or antibody treatment for cancer, including immunotherapy

  • are having an intense course of radiotherapy (radical radiotherapy) for lung cancer

  • are having targeted cancer treatments that can affect the immune system (such as protein kinase inhibitors or PARP inhibitors)

  • have blood or bone marrow cancer (such as leukaemia, lymphoma or myeloma)

  • have had a bone marrow or stem cell transplant in the past 6 months, or are still taking immunosuppressant medicine

  • have been told by a doctor they you have a severe lung condition (such as cystic fibrosis, severe asthma or severe COPD(Chronic Obstructive Pulmonary Disease))

  • have a condition that means they have a very high risk of getting infections (such as SCID or sickle cell)

  • are taking medicine that makes them much more likely to get infections (such as high doses of steroids)

  • have a serious heart condition.

Moderate risk (clinically vulnerable)

COVID-19 is a new disease. Currently there are limited data and information about the impact of underlying medical conditions and whether they increase the risk for severe illness from COVID-19. Based on what is known at this time, people who might be at an increased risk for severe illness from COVID-19 are those who:

  • have a lung condition that's not severe (such as asthma, COPD, emphysema or bronchitis)

  • have heart disease (such as heart failure)

  • have diabetes

  • have chronic kidney disease

  • have liver disease (such as hepatitis)

  • have a condition affecting the brain or nerves (such as Parkinson's disease, motor neurone disease, multiple sclerosis or cerebral palsy)

  • have a condition that means they have a high risk of getting infections

  • are taking medicine that can affect the immune system (such as low doses of steroids)

  • are very obese (a BMI of 40 or above)

The CDC in the USA gives a similar list but lists smoking and hypertension (high blood pressure) as a moderate risk. 

Below show the statistics of comorbidities (more than one illness or disease at the same time) observed in COVID-19 patients in both Italy and New York which are very similar and both show Hypertension as the leading comorbidity followed by diabetes.  The study in New York as of April 6th showed that 86.2% of the states deaths involved at least one comorbidity.


A journal published in the NCBI (National Center for Biotechnological Information) in the US concluded the following:

Due to COVID-19 being a relatively new and understudied disease, the data available is limited. However, from the cases that emerged, it was observed that comorbidities increase the chances of infection. Based on current information and clinical expertise, the elderly, especially those in long-term care facilities, and people of any age with serious underlying medical conditions are at a greater risk of getting COVID-19. The elderly, a vulnerable population, with chronic health conditions such as diabetes and cardiovascular or lung disease are not only at a higher risk of developing severe illness but are also at an increased risk of death if they become ill. People with underlying uncontrolled medical conditions such as diabetes; hypertension; lung, liver, and kidney disease; cancer patients on chemotherapy; smokers; transplant recipients; and patients taking steroids chronically are at increased risk of COVID-19 infection.

A meta-analysis study on COVID-19 comorbidities, had a total of 1786 patients, of which 1044 were male and 742 were female with a mean age of 41 years old. The most common comorbidities identified in these patients were hypertension (15.8%), cardiovascular and cerebrovascular conditions (11.7%), and diabetes (9.4%). The less common comorbidities were coexisting infection with HIV and hepatitis B (1.5%), malignancy (1.5%), respiratory illnesses (1.4%), renal disorders (0.8%), and immunodeficiencies (0.01%).

Patients with moderate to severe asthma are at a disadvantage because this virus affects their respiratory tracts, leading to increased asthmatic attacks, pneumonia, and acute respiratory distress. According to the CDC’s morbidity and mortality weekly report, 34.6% of patients aged 18 to 49 years old have an underlying chronic lung disease, such as asthma.


Over 180 countries have been affected by COVID-19, resulting in mass death worldwide. As cases evolve globally, it has been noted that persons with underlying chronic illnesses are more likely to contract the virus and become severely ill.

Due to SARS CoV-2 being a relatively new virus, the data available is limited. However, patients with comorbidities have more deteriorating outcomes compared with patients without. COVID-19 patients with history of hypertension, obesity, chronic lung disease, diabetes, and cardiovascular disease have the worst prognosis and most often end up with deteriorating outcomes such as ARDS and pneumonia. Also, elderly patients in long-term care facilities, chronic kidney disease patients, and cancer patients are not only at risk for contracting the virus, but there is a significantly increased risk of death among these groups of patients.

Of the cases reported worldwide, symptoms of COVID-19 ranged from mild respiratory disease to severe illness, which requires intubation and mechanical ventilation. Since there is a period where the patient is asymptomatic, and the incubation period is between 2 and 14 days, it is difficult to establish an early diagnosis, much less curb the transmission of the infection if the patient is unknowingly exposed. However, within this period, if respiratory symptoms develop, it is important to seek immediate care.

Therefore, patients with comorbidities should take all necessary precautions to avoid getting infected with SARS CoV-2, as they usually have the worst prognosis.