Abstract
OBJECTIVES: Patients with SLE have an increased risk of comorbidities and impaired survival. We aimed to assess whether various thresholds of oral CS (OCS) can predict development of infections, comorbidities, malignancies and survival in SLE using data from national health registries in Sweden. METHODS: All incident SLE cases, age >18 years, in Sweden (n = 5309) between 2005 and 2020 and matched population controls (n = 26 545) were included and followed until 2020, a total of 257 942 patient years. Data from national registers were retrieved including information from the National Prescribed Drug Register. Risk factors were analysed using time-dependent Cox regression models. RESULTS: Compared with no OCS, >0 to <5.0 mg/day, 5.0-7.5 mg/day as well as >7.5 mg/day OCS predicted development of infections (pneumonia, influenza, herpes zoster and urinary tract infection), osteoporosis, osteonecrosis, gastroduodenal ulcers, cataracts, hypertension and mortality (all P < 0.05). OCS >0 to <5.0 mg/day was associated with lower hazard ratios for these comorbidities than higher doses of OCS. Fifteen years after diagnosis, 48% of patients were taking OCS at a median dose of 5.7 mg/day. A small reduction of OCS treatment 5 years after diagnosis in patients diagnosed with SLE 2006-10 compared with 2011-15 was observed, 49% vs 46% respectively (P = 0.039). CONCLUSION: Results highlight the potential harm associated with even low OCS dose treatment in SLE and the need to judiciously use OCS at the lowest possible dose to maximize efficacy and minimize harm.