Endocrine Abstracts

Context: Secondary adrenal insufficiency (SAI) has been identified in over 22% of adults using inhaled corticosteroids (ICS).¹ This has been co-related with the total daily dose and type of ICS along with individual genetic susceptibility among the subjects using ICS.^1,2 Our recent paper suggested that 2.8% of adults with euvolaemic hyponatremia admitted to the hospital had ICS related SAI.³

Objective: To determine prevalence of SAI among chronic users of ICS in India along with determining the association of SAI with the type and total daily dose of ICS and baseline clinical clues to the presence of SAI.

Methods: Adult patients using ICS for over 4 weeks were included after informed consent from among patients seen in medical and respiratory clinics of a tertiary care hospital in India. Critically unwell patients, those who received oral or intravenous steroids in the past 6 months and those already having SAI were excluded. Baseline ICS dose and type were converted to fluticasone dose equivalents as per National Asthma Education Expert panel and classified as having high (>1gm/day), moderate (0.5-1gm/day) or mild(<0.5gm/day) exposure.⁴Baseline demography and presence of symptoms suggestive of SAI was recorded. An Acton Prolongatum™ Stimulation test (APST) was done on all patients to evaluate SAI.⁵ A cut-off cortisol value of <18 mg/dL after 60 min of APST was used to diagnose SAI.

Results: Seventy-five patients (F43:M32) with a mean age of 54.9±15 years were included and underwent APST testing. Among them 34 (45.3%) had SAI. There was no difference in the prevalence of SAI with type or dosing of ICS (1.0±0.4 vs. 1.1±0.4gm/day p-value=0.2). Clinically patients with asthma (52.9%) had more SAI than those with chronic obstructive airway disease (23.5%) (p-value=0.04). Among symptoms those with baseline nausea had more prevalent SAI (9.7% vs.29.4%, p-value=0.03). There was a suggestion that longer use of ICS (3.3±3.5 vs 4.7±3.7 years, p-value=0.07) was associated with more SAI.

Conclusion: Among patients who are on long-term ICS around 45% have SAI, which may require appropriate replacement during stressful periods. Clinically patients with chronic asthma, those with longer use of ICS and those who have nausea may be more likely to have SAI. The dose and type of ICS was not associated with the presence of AI.

References: 1. Lancet Respir Med. 2018; 6: 442-450 2. Arch Intern Med. 1999;159(9):941-955. 3. Endocr Connect. 2021;10(12):1623-1631. 4. Eur Respir J. 2013; 42: 79–86 5. Eur J Endocrinol. 2019;181(6):639-645.