Cortical microinfarcts along the Alzheimer’s disease continuum in adults with Down syndrome ‐ an update

Abstract

AbstractBackgroundCortical microinfarcts (CMI) are emerging biomarkers of vascular damage associated with cognitive decline and are frequent in sporadic AD (sAD) patients. However, no study assessed CMI in Down syndrome (DS), a genetically determined form of AD. Therefore, we aimed to assess CMI’s frequency in adults with DS, sAD, and cognitively unimpaired euploid controls and its relationship with age, sex, clinical status, and APOE ε4 carriership.MethodCross‐sectional study. We included 175 participants with 3T‐MRI: 64 with DS (39 asymptomatic [aDS], 11 prodromal AD [pDS], and 14 AD‐dementia [dDS]), 62 with sAD (41 prodromal AD, 21 AD dementia), and 49 controls. A neuroradiologist blind to participants’ data visually analyzed the 3T‐MRI images following a validated protocol to detect CMI (Figure 1). We compared CMI’s prevalence in the different clinical groups along the AD continuum in DS and sAD, in APOE ε4 carriers vs. non‐carriers, and males vs. females using Chi‐square, Mann‐Whitney, or Kruskal‐Wallis tests when appropriate.ResultCMI’s prevalence was 7.8% in DS (5.1% in aDS, 21.4% in pDS, and 0% in dDS [p = 0.085]), 17.7% in sAD (22.0% in prodromal AD and 9.5% in AD dementia [p = 0.389]), and 10.2% in controls (p = 0.207). CMI frequency increased with age in DS, sAD, and controls (Table 1). Regarding sex, CMI’s frequency was 10% in men and 5.9% in women with DS (p = 0.884), and 27.3% in men and 12.5% in women with sAD (p = 0.267). In controls, CMIs’ frequency was 10% in men and 10.3% in women (p = 1.000). Regarding APOEε4 carriership, CMI’s prevalence was 21.4% in APOEε4 carriers and 9.1% in non‐carriers in sAD (p = 0.428), 8.7% in carriers and 6.0% in non‐carriers in DS (p = 1.000), and 8.3% in carriers and 8.6% in non‐carriers controls (p = 1.000) (Table 2).ConclusionCMI’s prevalence increased with age, but was not different in DS, sporadic AD, and controls. Also, sex and APOEε4 carriership did not impact the prevalence of CMI in the three study groups.