No excess fracture risk with inhaled steroids for childhood asthma
Use of inhaled corticosteroids (ICSs) for childhood asthma was not associated with an increased risk of bone fractures compared with nonuse, allaying concern that ICS may adversely affect bone health similarly to systemic corticosteroids, a new study suggests.
“Use of inhaled ICS for the treatment of paediatric asthma should not be limited based on fear of fracture,” urged the researchers.
The population-based nested case-control study used health administrative databases to identify 3,884 cases of children (aged 2–18 years) diagnosed with asthma and had a fracture after diagnosis. They were matched to four fracture-free controls with asthma (n=15,536) according to birth date, sex, and age of asthma diagnosis. [JAMA Pediatr 2017;doi:10.1001/jamapediatrics.2017.3579]
The participants were classified into four categories of ICS use, depending on when they filled their prescription prior to the index date: current user (90 days prior), recent user (91–180 days prior), past user (181–365 days), or no use.
Based on a multivariable regression analysis, having a fracture after being diagnosed with asthma was not significantly associated with current ICS use (adjusted odds ratio [OR], 1.07; p=0.20), recent ICS use (OR, 0.96; p=0.53), or past ICS use (OR, 1.00; p=0.86) compared with nonuse, after adjusting for sociodemographic factors and use of other medication.
However, the risk of fracture was increased by 17 percent (OR, 1.17; p=0.01) with the use of systemic steroids vs nonuse in the past 1 year. The magnitude of increase was even larger in a subgroup analysis of girls only (OR, 1.25), while the effect was not statistically significant in the boy subgroup.
“There was also evidence of a potential dose effect of systemic corticosteroids, as only those children in the highest dose category had increased odds of fracture compared with no use,” noted the researchers.
Children with the highest estimated prednisone or daily equivalent dose (>30 mg) had a 41 percent increased risk of fracture vs nonuse (OR, 1.41; p=0.002), while there were no significant associations at lower doses.
“Clinicians using ICSs to optimize the control of childhood asthma should be reassured by the lack of association with fractures; fear of fracture is not a reason to limit the therapeutic use of ICSs,” cautioned the researchers.
“Furthermore, asthma control with ICSs might decrease the likelihood of asthma exacerbations requiring systemic corticosteroid use, so wider appropriate use of ICSs may potentially lead to a reduced fracture risk,” they added.
As the study is based on administrative databases, data on individual-level risk factors were unavailable, such as physical activity, nutrition (vitamin D and calcium levels), and disease severity.
The researchers called for future studies to look into the role of asthma severity and fracture risk, “as some of the increased risk associated with systemic corticosteroids may be due to the underlying illness itself.”