Predictors of hospital outcomes among patients with posterior reversible encephalopathy syndrome

Occipital cerebral microbleeds as a predictor of intracranial hemorrhage in posterior reversible encephalopathy syndrome

BACKGROUND AND OBJECTIVES

Intracranial hemorrhage (ICH), which often occurs in cases of posterior reversible encephalopathy syndrome (PRES), is regarded as a significant predictor of poor disease outcomes. While ICH and cerebral microbleeds (CMBs) can occur due to uncontrolled hypertension, the relationship between these conditions remains unclear.

METHODS

This retrospective case-control study categorized PRES patients according to the presence of ICH on the day of symptom onset. The presence of CMBs or intracranial bleeding was assessed using gradient echo (GRE), susceptibility-weighted imaging (SWI), and computed tomography (CT) scans. CMBs and intracranial hemorrhage were classified according to size (≥5 mm). The brain was divided into nine regions, with the four areas excluding the fronto-parieto-occipito-temporal lobe and the cerebellum grouped as deep structures. Mediation analysis was conducted to evaluate the potential causal relationship in which ICH may mediate the association between the presence of CMBs and complete remission.

RESULTS

The study included 165 patients with PRES, among whom 19 (11.52 %) presented with ICH. The maximal systolic blood pressure at the time of PRES occurrence was not significantly different between PRES patients with ICH and those without (180.0 ± 20.8 mmHg vs. 183.5 ± 29.2 mmHg, p = 0.53). However, PRES cases with ICH exhibited a higher prevalence of CMBs in the parietal and occipital lobes (parietal lobe: 9 [52.9 %] vs. 27 [21.3 %], p = 0.005; occipital lobe: 8 [47.1 %] vs. 15 [11.8 %], p < 0.001). Logistic regression analysis revealed that the presence of CMBs in the occipital lobe was positively associated with the presence of ICH in PRES (odds ratio = 10.71, 95 % CI 1.44-79.63, p = 0.020).

DISCUSSION

This study suggests that in PRES, ICH may occur due to a vulnerable endothelium in the occipital lobe. Furthermore, cases with CMBs in the occipital lobe may experience ICH as a complication of PRES.

Frequency of ischaemic stroke and intracranial haemorrhage in patients with reversible cerebral vasoconstriction syndrome (RCVS) and posterior reversible encephalopathy syndrome (PRES) - A systematic review

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS) may cause ischaemic stroke and intracranial haemorrhage. The aim of our study was to assess the frequency of the afore-mentioned outcomes.

METHODS

We performed a PROSPERO-registered (CRD42022355704) systematic review and meta-analysis accessing PubMed until 7 November 2022. The inclusion criteria were: (1) original publication, (2) adult patients (≥18 years), (3) enrolling patients with PRES and/or RCVS, (4) English language and (5) outcome information. Outcomes were frequency of (1) ischaemic stroke and (2) intracranial haemorrhage, divided into subarachnoid haemorrhage (SAH) and intraparenchymal haemorrhage (IPH). The Cochrane Risk of Bias tool was used.

RESULTS

We identified 848 studies and included 48 relevant studies after reviewing titles, abstracts and full text. We found 11 studies on RCVS (unselected patients), reporting on 2746 patients. Among the patients analysed, 15.9% (95% CI 9.6%-23.4%) had ischaemic stroke and 22.1% (95% CI 10%-39.6%) had intracranial haemorrhage. A further 20.3% (95% CI 11.2%-31.2%) had SAH and 6.7% (95% CI 3.6%-10.7%) had IPH. Furthermore, we found 28 studies on PRES (unselected patients), reporting on 1385 patients. Among the patients analysed, 11.2% (95% CI 7.9%-15%) had ischaemic stroke and 16.1% (95% CI 12.3%-20.3%) had intracranial haemorrhage. Further, 7% (95% CI 4.7%-9.9%) had SAH and 9.7% (95% CI 5.4%-15%) had IPH.

CONCLUSIONS

Intracranial haemorrhage and ischaemic stroke are common outcomes in PRES and RCVS. The frequency reported in the individual studies varied considerably.