Endocrine Abstracts

Context: Previous studies have suggested that infections are an important cause of death in patients with Addison’s disease, but epidemiological studies on the frequency of infections in this population are scarce.

Design and setting: We conducted a cohort study, using data from the Dutch PHARMO record linkage system, linking patients’ demographics and medical histories to the use of prescription drugs, diagnostic and therapeutic data from hospital and general practitioner records.

Participants: From a cohort of oral glucocorticoid users, 390 patients with Addison’s disease were identified by assessing concurrent use of glucocorticoids and mineralocorticoids using pharmacy dispensing records. A reference cohort (n=1933) with the same age and sex distribution was sampled from patients not using glucocorticoids.

Outcome measure: Incidence rates and incidence rate ratios (IRR) of infectious events and hospital admission for infection.

Results: The risk of infectious episodes among patients with Addison’s disease was 1.5 times higher compared to controls, yielding an overall incidence rate of 59.2/100 person-years, with a crude IRR of 1.61 (95% CI 1.51–1.72). The IRR decreased slightly to 1.58 (95% CI 1.47–1.70) after adjustment for confounding co-medication and -morbidity. Regarding hospital admission for infection we also found higher rates among Addison patients (3.8/100 person-years versus 0.8/100 person-years) with a crude and adjusted IRR of respectively 5.02 (95% CI 3.66–6.87) and 4.34 (95% CI 3.04–6.22).

Conclusion: Patients with Addison’s disease had an increased risk of infectious events and hospital admissions related to infection.