Background Renal impairement in spondyloarthritis (SpA), although uncommon, may include secondary renal amyloidosis (AA type), non-steroidal anti-inflammatory drug (NSAID) nephropathy, and glomerulonephritis. Data on the prevalence of renal impairement in SpA are relatively rare and usually come from small or retrospective studies.
Objectives To assess the prevalence and associations of renal dysfunction in patients with SpA.
Methods COMOSPA was an international (22 participating countries from four continents) multicentric study on comorbidities in SpA. Renal function was assessed from the estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease (MDRD) equation. SpA characteristics, risk factors for renal impairment were collected. NSAID use was assessed by the currently (last 3 months) intake. Logistic regression models were constructed from variables which were significantly associated with an eGFR of <60ml/min/1.73m2 or clinically relevant.
Results Of the 3984 recruited patients, after excluding of outliers and patients for whom eGFR was not available, 2098 (52.6%) were analysed (male gender: 63.5%; age: 45.3 years; disease duration: 8.6 years; HLAB27+: 53.7%; BASDAI: 3.6/10). A total of 153 patients (5.2%, mean age 53.6 years) had an eGFR <60 ml/min/m2. In univariate analysis, renal impairment was associated with age (p<0.001), HLAB27 positivity (p<0.001), several cardiovascular risk factors (history of hypertension [p<0.001], systolic blood pressure [p=0.03], diabetes [p=0.005] and the Framingham Risk score [p<0.001]), disease activity scores (BASDAI [p=0.001], ASDAS-CRP [p<0.001]), functionnal parameters (BASFI [p<0.001], HAQ [p<0.001]), inflammatory biomarkers (ESR and CRP, both p<0.001), but not with disease duration, disease sevrity (bamboo spine, hip replacement) or NSAID current intake.
Conclusions Renal impairment is not rare in SpA and is associated with age, disease severity and inflammation but not with cardiovascular risk factors or NSAID currently use.
Disclosure of Interest None declared