The number of adults diagnosed with arthritis has risen at least 40% between 2004 and 2020, according to research by Keele University.
Inflammatory arthritis consists of several conditions which cause joint pain and swelling.
Its three main types - rheumatoid arthritis, psoriatic arthritis, and axial spondyloarthritis - cause long-term pain and disability and have high costs to the UK economy.
In 2020 over 1% of adults and over 2.5% of those aged over 65 years in England had a diagnosis of one of these conditions.
Lead author, Dr Ian Scott said: “Our findings have significant implications for the NHS in England. Many studies have shown that the earlier people with inflammatory arthritis receive specialist treatment the better they do, and it is very important that people with new onset inflammatory arthritis or suffering a flare of their arthritis are seen quickly. Organising NHS services to enable this is vital.
“Our results show that these conditions are more common in people aged over 65 years. This highlights the need to consider older people when planning arthritis NHS services.
“We need to particularly make sure that the widespread move to online healthcare does not adversely affect older people with arthritis, as other studies have shown they are less likely to use the internet and have the essential digital skills to access it independently.”
Watch: Nine-year-old uses her juvenile arthritis to help others with disease
Read more: Ulrika Jonsson on her arthritis pain
Scott says that the increase in prevalence is probably due to people living longer, with the death rate of patients with rheumatoid arthritis having dropped sharply, according to previous research.
Better record-keeping in GP surgeries and changes to diagnosis criteria probably also played a part, Scott suggested.
The study was published in The Lancet Regional Health – Europe and looked at the proportion of adults in England with a diagnosis of one of these three conditions in each year from 2004 to 2020.
The research team looked at data from a large GP database - the Clinical Practice Research Datalink Aurum - which currently includes information from over 1,400 GP practices across 20% of England.
They looked at data from 2004 to 2020, to understand how the prevalence of inflammatory arthritis diagnoses have changed in that time.
Deborah Alsina, chief executive of the charity Versus Arthritis told The Times, “These conditions can have a huge impact on someone’s life such as reducing their ability to work, care for their family or even live independently. Yet all too often they are dismissed as ‘just a few aches and pains’.”
Alsina said a rise in diagnosis should not be alarming because it meant more people would get treatment, leading to assessment of linked conditions, such as heart disease or osteoporosis.
“It is essential that people know the symptoms of inflammatory arthritis and tell their GP. A quick diagnosis can help to avoid joint damage.”