New study of seven million records reveals who gets long COVID

First published by Macquarie University

A study of 7 million medical records found that in Australia, patients with long COVID are more likely to be women than men, or people aged 40-59 and those living in a high socioeconomic area. They usually have pre-existing health problems.

The findings, published by Macquarie University’s Australian Institute of Health Innovation in the Medical Journal of Australia, add key insights about the demographics and clinical profile of people most likely to be diagnosed with long COVID.

The global COVID pandemic was declared over by health authorities in 2023, but the impact of long COVID continues to pose a challenge to medical care and research.

Most people infected with SARS-CoV-2 (COVID) fully recover after a few weeks, but some patients face persistent symptoms for many months after the infection.

There is no universally agreed definition of long COVID, but common symptoms include shortness of breath, cough, chest pain, fatigue, brain fog, dizziness, abdominal pain or nausea and even organ damage.

The Australian Institute of Health and Welfare estimates up to 10 per cent of COVID patients will develop long COVID, imposing a significant burden on the health system and economy.

But the true frequency and factors associated with long COVID in Australia is poorly understood, impeding evidence-based interventions to treat and provide services to patients.

The Australian difference

Macquarie University researchers led by Professor Andrew Georgiou from the Australian Institute of Health Innovation set out to change that by analysing millions of patients records from general practitioners (GPs) in Sydney and Melbourne.

“Improving our understanding of long COVID, including who is being diagnosed, is vital to enhancing patient access to appropriate care, services and treatment,” Professor Georgiou says.

Overseas research suggests demographic factors and pre-existing conditions as potential risk factors of long COVID.

But Professor Georgiou said Australians experienced the pandemic differently from most other countries, with the majority of exposure to COVID occurring after vaccination and predominantly from the Omicron variant. This unique context suggests Australia should have a lesser burden of long COVID than overseas, but there is a lot more we need to find out, he says.

The study of 7 million medical records found that in Australia, patients with long COVID are more likely to be women than men, or were middle-aged, mostly living in a high socioeconomic area or those with pre-existing health problems.

We encourage GPs to listen to patients and to record symptoms of long COVID in medical records otherwise the condition will continue to be under-represented in health statistics.

Mental health, respiratory conditions such as asthma or emphysema, cancer or musculoskeletal conditions such as arthritis were among the chronic health conditions found in patients diagnosed with long COVID.

Uncertainty in making and documenting a definitive long COVID diagnosis while evidence of the condition is still emerging suggests the study almost certainly underrepresented the prevalence of the illness.

Good records crucial

Professor Georgiou says GP practices are at the frontline of identifying and managing long COVID.

“General practice plays a critical role in Australia’s response to long COVID, not least because that is the first place people go when they are unwell or concerned,” he says.

GP and a co-author of the study, Associate Professor Chris Pearce, also says GPs have a crucial role in unlocking the mysteries of long COVID and providing better care to patients.

“We encourage GPs to listen to patients and to record symptoms of long COVID in medical records otherwise the condition will continue to be under-represented in health statistics,” Associate Professor Pearce says.

“Better recording leads to better understanding and better treatments. GPs are at the forefront of managing long COVID and are struggling to understand this complex disease. The more information we have to help them, the better.”