Factors associated with early deterioration after spontaneous intracerebral hemorrhage: a systematic review and meta-analysis

Abstract

Background and purpose: Spontaneous intracerebral hemorrhage (ICH) is a devastating form of stroke with a poor prognosis overall. We conducted a systematic review and meta-analysis to identify and describe factors associated with early neurologic deterioration (END) after ICH.

Methods: We sought to identify any factor which could be prognostic in the absence of an intervention. The Cochrane Library, EMBASE, the Global Health Library, and PubMed were searched for primary studies from the years 1966 to 2012 with no restrictions on language or study design. Studies of patients who received a surgical intervention or specific experimental therapies were excluded. END was defined as death, or worsening on a reliable outcome scale within seven days after onset.

Results: 7,172 abstracts were reviewed, 1,579 full-text papers were obtained and screened. 14 studies were identified; including 2088 patients. Indices of ICH severity such as ICH volume (univariate combined OR per ml:1.37, 95%CI: 1.12-1.68), presence of intraventricular hemorrhage (2.95, 95%CI: 1.57-5.55), glucose concentration (per mmol/l: 2.14, 95%CI: 1.03-4.47), fibrinogen concentration (per g/l: 1.83, 95%CI: 1.03-3.25), and d-dimer concentration at hospital admission (per mg/l: 4.19, 95%CI: 1.88-9.34) were significantly associated with END after random-effects analyses. Whereas commonly described risk factors for ICH progression such as blood pressure, history of hypertension, and ICH growth were not.

Conclusions: This study summarizes the evidence to date on early ICH prognosis and highlights that the amount and distribution of the initial bleed at hospital admission may be the most important factors to consider when predicting early clinical outcomes.

Figure 1. Literature search flow.

Studies were excluded because they didn't appear to measure deterioration or adult ICH during abstract screening (n = 4229), full-text versions could not be obtained (n = 53), none of the >3000 words or phases for END could be found in the full-text (n = 1226), authors did not measure END in adult ICH patients (n = 264), a measure of risk could not be estimated (n = 47), all patients received an experimental or specific medical therapy or it was unclear (n = 12), patients received a surgical intervention before END was measured or it was unclear (n = 44), the prognostic factor was not defined (n = 1), END was not defined (n = 6), the reliability of the measure used to define END was poor or unclear (n = 1), the timing of the measurement of the prognostic variable or END was not defined or unclear (n = 109), the study was the only study to describe a specific prognostic factor (n = 1), or the study did not describe new data (n = 15).

Figure 2. Prognostic factors identified and their association with early neurologic deterioration (END).

Effect estimates are reported as odds ratios (OR) with 95% confidence intervals (CI). Subtotal denotes the overall combined random-effects OR for each given factor. Point estimates lying to the right of one suggest an increased odds of END per one unit increase in the reported units. Dichotomous factors are coded and reported as 1 vs. 0 (e.g. deep location = 1, lobar = 0). Confidence intervals (horizontal lines encompassing the point estimates) which cross one suggest no association. IVH denotes intraventricular extension. SAH denotes subarachnoid extension. The boxes surrounding the point estimates represents the relative weight each study has within the factor comparison; such that larger boxes represent greater weight in the overall combined estimates.