Inhaled corticosteroids: Ocular safety and the hypothalamic-pituitary-adrenal axis

Abstract

Background: Inhaled corticosteroids (ICSs) effectively deliver corticosteroids to target sites in the lungs and reduce systemic effects compared with oral corticosteroids, but long-term systemic exposure from inhaled corticosteroids remains a concern.

Objective: To discuss ICS systemic effects on the eye and the hypothalamic-pituitary-adrenal (HPA) axis.

Methods: Relevant publications were used to augment discussion.

Results: The most common adverse effects of exogenous corticosteroids on the eye are secondary open-angle glaucoma and posterior subcapsular cataracts. Study findings conflict about whether ICS use is associated with increased risk of glaucoma or elevated intraocular pressure, but studies might not have addressed the question in the right population. Increased risk of glaucoma may be limited to a few susceptible individuals, such as individuals with a family history of glaucoma. Large population-based studies reveal that high daily doses or high lifetime exposure of ICSs is associated with a higher risk of posterior subcapsular cataracts. More research is needed to determine the risk from low to moderate doses during long periods. For the HPA axis, there are several measures for detecting systemic effects. Short-term measures are more sensitive for detecting the systemic effects of ICSs but have less predictive value in identifying clinically important adverse effects. Several studies have found that ICSs have a dose-dependent effects on cortisol suppression that can be used to estimate equivalent dosages among ICSs.

Conclusion: Because of systemic effects on the HPA axis, high doses of ICS should be avoided where possible. Adult patients undergoing high-dose or long-term ICS therapy should be monitored for cataracts.