While intracranial atherosclerotic disease (ICAD) is often cited in the context of its greater prevalence among patients in China and other parts of Asia, discussions at the recent BRAIN conference (2–4 December, London, UK) emphasised its relevance as an underlying—and also under-addressed—cause of ischaemic stroke across many global regions.
“If we can tackle this, and if we can get this right in the next 2–3 years, it’s going to be a big win for us,” BRAIN conference director Paul Bhogal (Royal London Hospital, London, UK) told NeuroNews, also commenting that ICAD is “absolutely” a globally relevant stroke aetiology.
Leonard Yeo (National University Health System, Singapore) was one of multiple speakers to highlight how “widespread” ICAD is across stroke populations, noting that it has a higher prevalence in Asian patients but is “not insignificant” among Caucasian patients. He relayed that current data suggest ICAD is present in 10% of Caucasian patients with ischaemic stroke, compared to 20–30% of patients across Asia and at least 40% in those in China specifically.
In addition, Yeo outlined a number of studies that have attempted to pinpoint the prevalence of symptomatic ICAD within specific countries, with research papers from 2014 indicating rates of 36% and 21.9% in India and Japan, respectively, and analyses from earlier this year suggesting a frequency as high as 25.2% in Brazil.
“We are seeing it more—because we are now looking for it more—in Europe too,” commented Tommy Andersson (Karolinska University Hospital, Stockholm, Sweden), who moderated the day’s first ICAD-focused session.
A later talk from Osama Zaidat (Mercy Hospital, Toledo, USA) helped to expand on this further. Citing a 2024 paper in the journal Stroke, Zaidat noted worldwide ICAD prevalence ranging from 56% in South Korea, 54% in Singapore, and 47% in Thailand, to 16% in Europe and 12% in the USA.
“I have been doing this for years and years, and it is a challenging disease,” he added, detailing that rates of ICAD recurrence are 10 times those seen in atrial fibrillation, before also asserting that “what’s really missing” from the current appreciation of ICAD is the fact that “not all lesions are the same”. “We are lumping them [in] together, but I think they are different.”
The session also saw Rashmi Saraf (King Edward Memorial Hospital, Mumbai, India) deliver insights on prevalence and treatments across the Indian subcontinent, broadly corroborating the study cited by Yeo in stating that 25–35% of her home country’s hyperacute stroke cases appear to be caused by underlying ICAD—a rate that is currently increasing in younger patient populations. She went on to report that approximately 2,000–2,500 angioplasties and stenting procedures are performed each year in India.
“We can’t wait just on medical management at our [high-volume] centre,” Saraf averred. “We are much more aggressive in treating them with angioplasty and stenting compared to the rest of the world, given the more extensive lesions with higher rates of recurrence.”
In addition, insights presented by Davor Pavlin-Premrl and Bruce Campbell (both University of Melbourne, Melbourne, Australia) revealed that, in Australia—a country thought to have a relatively low prevalence of underlying ICAD—the majority of cases are seen in patients with European ancestry.
The first day of the conference also saw Ameer Hassan (Valley Baptist Medical Center, Harlingen, USA) relay that ICAD is more common than many people assume in parts of the USA, attributing much of the 30% rate he observes at his centre to Texas’ “very large” Hispanic population.
As was borne out through much of the discussion at BRAIN 2024, Hassan reiterated that ICAD is a “problem area” in stroke treatment, with a lack of descriptive autopsy studies and effective animal models being among numerous contributing factors. The speaker commented that, in spite of this, the majority of neurovascular companies do not seem to feel ICAD represents a significant enough market to truly prioritise when it comes to product development.
However, Hassan—along with Zaidat, Ricardo Hanel (Baptist Neurological Institute, Jacksonville, USA) and others—was keen to emphasise that “we need better devices” in order to deliver more effective and individualised treatments in stroke patients with ICAD.
Some of the novel technologies currently being investigated in this space were showcased later in the day, with Satoshi Tateshima (University of California Los Angeles Medical Center, Los Angeles, USA) presenting a first-in-human (FIH) trial involving a self-expandable, temporary dilation system (TG Medical) and Andersson taking to the podium to discuss a stent device designed explicitly with ICAD cases in mind (Ceroflo).
