People taking steroid inhalers or tablets for asthma are at a significantly increased risk of osteoporosis and fragile bones, according to new research.
Experts behind the study recommended that medics should ensure people take the drugs for as short a duration as possible and doses should be reduced if safe to do so.
They argued that the higher the cumulative dose and the longer the period of treatment, the greater the risks.
Researchers from the University of Nottingham, writing in the journal Thorax, looked at the use of inhaled (ICS) and oral (OCS) corticosteroids for controlling asthma.
They said research so far has proved inconclusive, and so analysed data on patients with asthma and either osteoporosis or fragility fractures.
The Clinical Practice Research Datalink (CPRD) Gold database, which covers more than 15.4 million UK patients, was used alongside hospital admissions data for July 2018.
The team compared people without osteoporosis and asthma and also looked at whether people were prescribed bisphosphonates to stave off osteoporosis, and whether they took bone strengthening vitamin D and calcium supplements.
The results suggested that people with asthma given two to three steroid tablet prescriptions in the previous 12 months were more likely to have osteoporosis.
Those given nine or more prescriptions and cumulative doses of 2,500mg or more had more than four times the risk of those who were not prescribed the steroids.
They were also more than twice as likely to suffer a fragility fracture.
Meanwhile, those given 11 or more prescriptions for inhaled steroids were 60% more likely to have osteoporosis and 31% more likely to have fragility fractures than those not prescribed these drugs.
The authors said they found it “disappointing” that only around half of patients prescribed steroid tablets and even fewer prescribed steroid inhalers were also prescribed bisphosphonates in the year leading up to a diagnosis of osteoporosis or fragility fracture.
They said: “Current guidelines on asthma do not fully cover the management of bone comorbidities and no specific bone protection guidance is given.
“Our results suggest that risk and prevention of osteoporosis and (fragility fractures) should be addressed explicitly in future guideline updates.
“Both (oral) and (inhaled) steroids are associated with an increased risk of osteoporosis and (fragility fracture) in people with asthma.
“The use of (these drugs) should be kept to the minimum necessary to treat symptoms and should be stepped down if symptoms and exacerbations are well managed.”
Around one in 11 children and one in 12 adults in the UK receive some treatment for asthma.
Andrew Whittamore, clinical lead for Asthma UK and the British Lung Foundation, and a practising GP, said: “This observational study adds to the growing body of evidence showing that, whilst oral steroids can be life-saving during an asthma attack, they can be debilitating for those who are prescribed them repeatedly, long term.
“Side-effects can range from osteoporosis, weight gain, mood swings and depression.
“Repeated use means that someone’s asthma is not well-controlled; for some it could even be a sign that they have severe asthma, the most serious and life-threatening form of the condition.
“It’s essential that people who fall into this category are referred to a specialist so they get the care they need, and, if eligible, access alternative treatments such as biologics which can transform their treatment.
“Preventer inhalers contain a low dose of steroids and if someone with asthma has been prescribed a preventer inhaler, and is using it correctly, they are less likely to need to take steroid tablets.
“It’s crucial that anyone with poorly controlled asthma should have their diagnosis, adherence, inhaler technique and triggers checked before increasing their inhaled corticosteroids dose.
“With services continuing to be stretched during the pandemic and with winter being the deadliest season for people with respiratory conditions, it’s even more vital that people with uncontrolled and severe asthma can access basic care and are put on the right treatments, helping to keep them out of hospital.”
Osteoporosis is a condition that weakens bones, making them fragile and more likely to break.
It develops slowly over several years and NHS data suggests it is mostly diagnosed when a fall or sudden impact causes a bone to fracture.