Inclusion Criteria:  Age 30-60 years Admission between 01/09/2020 - 31/12/2021 Clinically suspected or Confirmed COVID-19 Reverse Transcription-Polymerase Chain Reaction (RT-PCR) test confirmed COVID-19 on admission No history of hypertension or current drug treatment for hypertension  Controls  Age 30-60 No history of hypertension No antihypertensive drugs Confirmed RT-PCR test negative and admission through Queen Elizabeth University Hospital immediate assessment unit and acute receiving units 01/04/2020 to 31/12/2021 or no history of SARS-CoV-2 infection or COVID-19  Exclusion Criteria:  Inability to give informed consent/lack of capacity Non-English, Arabic, Polish or Urdu speakers BMI >40 eGFR <60 ml/min Pregnancy History of  Cancer within 5 years Persistent atrial fibrillation Severe illness, at investigator discretion Prescription of BP lowering drugs Oral Corticosteroid (chronic use) Immunosuppressive agents Oral NSAIDs (chronic use)