Endocrine Abstracts

Background: Previous studies have found reduced health-related quality of life and employability in patients with autoimmune Addison’s disease (AAD). However, there are no large studies examining the economic cost of illness for the individual.

Objective: To study differences in income and work loss between patients with AAD and matched comparators.

Methods: In this cross-sectional study we linked the Swedish Addison Register and several Swedish national health registers to identify individuals of working age (18–64 years) with AAD and comparators from the general population, matched 1:5 by sex, age and region of residence. The study outcomes were taxable earnings, disposable income and mean annual days of work loss (sick leave or disability pension) during 2019. Quantile regression was used to calculate adjusted median differences in taxable earnings and disposable income (adjusted for age and sex), while linear regression was used to obtain adjusted mean differences in work loss days.

Results: We identified 1140 patients with AAD and 5700 comparators (51.6% female), with mean age 46.1 years. Type 1 diabetes was present in 15.7% of patients with AAD and 1.1% of the comparators. We found no significant difference in taxable earnings (P=0.48) or disposable income (P=0.43) between patients with AAD and their matched comparators. However, patients with AAD had significantly higher mean annual work loss, adjusted mean difference 14.4; 95% CI, 8.6–20.3 days, P<0.001. Subgroup analysis revealed that patients with short education (<9 years) or co-existence of type 1 diabetes had lower taxable earnings (P=0.02 and P=0.006), lower disposable income (P=0.007 and P=0.02) and higher mean annual work loss (P=0.004 and P<0.001).

Conclusion: Overall, patients with AAD have more work loss, but similar taxable earnings and disposable incomes compared to matched population comparators. One possible explanation is that the Swedish social welfare system partly compensates for the work loss financially. However, patients with AAD with lower levels of education or co-existent type 1 diabetes appear to be socioeconomically vulnerable.