Supplementary Material for: Is Regular Screening for Intracranial Aneurysm Necessary in Patients with Autosomal Dominant Polycystic Kidney Disease? A Systematic Review and Meta-analysis

Background: The prevalence of intracranial aneurysm in patients with autosomal dominant polycystic kidney disease (ADPKD) is higher than that among the general population. We performed a systematic review and meta-analysis on the prevalence and natural history of intracranial aneurysm among patients with ADPKD. Methods: Medline, Embase, Web of Science and Scopus, from inception to July 2016, were searched for studies reporting the occurrence of intracranial aneurysms among participants with ADPKD. Two authors independently assessed the eligibility of all retrieved studies and extracted data. Information on the prevalence of intracranial aneurysms and their natural history in participants with ADPKD was collected from all included studies. Results: Fifteen studies with 1,490 participants with ADPKD were pooled to study about the prevalence of intracranial aneurysm in participants with ADPKD, and the prevalence rate was found to be 10% (95% CI 7-13%). Studies from China, Japan and Europe (Germany, Poland) reported a higher prevalence of intracranial aneurysm. Having a family history of haemorrhagic stroke or intracranial aneurysm was a risk factor for aneurysm occurrence. Twenty-three percent (95% CI 15-31%) of the participants had multiple aneurysms. Most of the aneurysms were small (<6 mm) and located in the anterior circulation. Five studies with 171 participants (83 with 106 aneurysms at baseline and 88 without) were analyzed to understand the natural history of aneurysms, with an incidence of aneurysm growth, new aneurysm and aneurysm rupture of 1.84% (followed up for 435 person-years), 0.57% (1,227 person-years) and 0.13% (792 person-years) respectively. Conclusions: Screening for intracranial aneurysm is recommended in patients with ADPKD when there is a family history of haemorrhagic stroke or intracranial aneurysm and when they are from China, Japan or Europe (Germany, Poland). Based on existing data, regular imaging follow-up is not supported. High-quality, prospective studies are needed in the future.