Increased blood pressure variability following acute stroke is associated with poor long-term outcomes: a systematic review.

BACKGROUND: Blood pressure variability (BPV) in acute ischemic stroke (AIS) may be of prognostic significance. However, methodological heterogeneity of studies may contribute to inconsistent findings, and study findings are therefore not readily comparable. We investigated study methodologies which have assessed the long-term outcomes (≥7 days) of BPV post-AIS. MATERIALS AND METHODS: The literature search was conducted in OVID Medline, Embase, The Cochrane Library, and Web of Science following a predefined search strategy. Two reviewers independently assessed study eligibility and quality, and source data were extracted. RESULTS: Of 2044 studies identified, 19 observational studies and one case-control study were included; seven studies were additionally included. Twenty-two studies obtained good risk of bias ratings. Key findings were methodological heterogeneity and significant variability in the reporting of key criteria. Twenty-four studies reported intervals between blood pressure assessments; although 19 studies reported the monitoring device used, only eight studies reported the number of blood pressure measurements taken per visit. The majority measured supine blood pressure (n=13), and eight studies reported whether this was in the hemiparetic or unaffected arm. Sixteen studies defined BPV using SD and seven studies used only a single blood pressure parameter to quantify BPV. Increased BPV was associated with poorer neurological and functional outcomes, and death (n=23); other unfavorable outcomes included irregularly shaped lacunar infarcts, and impaired cognition (n=3). CONCLUSION: Methodological heterogeneity is frequently observed in studies, primarily because of incomplete study reporting. However, increased BPV is associated with adverse long-term outcomes. There is a need for prospective studies investigating BPV post-AIS to report full methodologies according to standardized criteria.