Diagnosis and risk factors for intracranial aneurysms in autosomal polycystic kidney disease: a cross-sectional study from the Genkyst cohort

Background Autosomal dominant polycystic kidney disease (ADPKD) is associated with an increased risk for developing intracranial aneurysms (IAs). We aimed to evaluate the frequency of diagnosis of IAs in the cross-sectional, population-based, Genkyst cohort, to describe ADPKD-associated IAs and to analyse the risk factors associated with the occurrence of IAs in ADPKD patients. Methods A cross-sectional study was performed in 26 nephrology centres from the western part of France. All patients underwent genetic testing for PKD1/PKD2 and other cystogenes. Results Among the 2449 Genkyst participants, 114 (4.65%) had a previous diagnosis of ruptured or unruptured IAs at inclusion, and similar to 47% of them had a positive familial history for IAs. Most aneurysms were small and saccular and located in the anterior circulation; 26.3% of the patients had multiple IAs. The cumulative probabilities of a previous diagnosis of IAs were 3.9%, 6.2% and 8.1% at 50, 60 and 70 years, respectively. While this risk appeared to be similar in male and female individuals <50 years, after that age, the risk continued to increase more markedly in female patients, reaching 10.8% versus 5.4% at 70 years. The diagnosis rate of IAs was >2-fold higher in PKD1 compared with PKD2, with no influence of PKD1 mutation type or location. In multivariate analysis, female sex, hypertension <35 years, smoking and PKD1 genotype were associated with an increased risk for diagnosis of IAs. Conclusions This study presents epidemiological data reflecting real-life clinical practice. The increased risk for IAs in postmenopausal women suggests a possible protective role of oestrogen.