Relationship between Kidney Dysfunction, Stroke Severity, and Outcomes in a Nigerian Tertiary Hospital: A Prospective Study

BACKGROUND

Stroke is a common neurologic disease associated with fatal outcomes. Kidney dysfunction may be an important predictor of stroke severity and outcome.

AIM

To determine the relationship between kidney dysfunction at admission and stroke severity and 30-day outcome.

MATERIALS AND METHODS

This was a prospective study that involved 150 stroke patients. Stroke severity at admission was assessed using the National Institutes of Health Stroke Scale (NIHSS). Renal dysfunction was assessed by the presence of albuminuria and or reduced glomerular filtration rate (GFR) at admission. Neurological outcome was assessed using mortality, modified Rankin Scale (mRS), and Glasgow Outcome Scale (GCS).

RESULTS

The mean age of the study participants was 61.0 ± 13.2 years. Renal dysfunction was present in 66% of the participants while the case fatality rate of stroke was 26%. Poor neurological outcome at 30 days was found in 44.1% of survivors. Those with albuminuria had lower GCS (P = 0.041), lower GFR (P = 0.004), higher mRS score on day 14 (P = 0.041) and day 30 (P = 0.032), and higher NIHSS score (P = 0.034). Independent predictors of 30-day mortality were albuminuria (Adjusted Odd Ratio (AOR) 3.60, 95%CI: 1.07-12.17) and increasing NIHSS score (AOR = 1.15, 95%CI: 1.04-1.28). Lower GCS (P < 0.001), elevated white blood cells (P = 0.003), serum creatinine (P = 0.048), and NIHSS score (P < 0.001) were associated with poor neurological outcome. NIHSS score was the only significant predictor of neurologic outcome (AOR: 1.25; CI: 1.11-1.41; P ≤ 0.001).

CONCLUSIONS

Kidney dysfunction was associated with stroke severity and mortality. However, it was not an independent predictor of neurological outcome.

The Efficacy and Safety of Roxadustat for Anemia in Patients With Chronic Kidney Disease: A Meta-Analysis

Background: Chronic kidney disease (CKD) is a global public health problem, and anemia is a common complication in CKD patients. Roxadustat (FG-4592) is an oral hypoxia-inducible factor (HIF) stabilizer. Roxadustat has been shown in studies to keep up with and increase hemoglobin better than placebo or erythropoietin. The purpose of this meta-analysis was to assess the efficacy and safety of roxadustat.

Methods: We searched CBM, CNKI, VIP, Wanfang Database, PubMed, Cochrane Library, Embase, and Web of Science for randomized controlled trials of roxadustat for the treatment of anemia in CKD patients. The papers were screened using rigorous criteria and their quality was assessed using the Cochrane 5.1.0 assessment manual for randomized controlled trials (RCTs). RevMan 5.3 was used to extract and synthesize data for meta-analysis.

Results: There were 8 RCTs (7 articles) in all, and 1,364 patients with chronic kidney disease anemia were involved. The overall quality of the studies included was satisfactory. The meta-analysis findings revealed that roxadustat can considerably enhance hemoglobin, transferrin, and total iron binding capacity (TIBC) in both dialysis-dependent (DD) and non-dialysis-dependent (NDD) patients: Hemoglobin (Hb): DD: [SMD = 0.23, 95% CI (0.01, 0.44), p = 0.04], NDD: [SMD = 2.08, 95% CI (1.23, 2.93) p < 0.000001]; transferrin: DD: [SMD = 0.78, 95% CI (0.24, 1.32), p = 0.004], NDD: [SMD = 1.37, 95% CI (0.76, 1.98), p < 0.0001]; TIBC: DD [SMD = 0.97, 95% CI (0.64, 1.29), p < 0.00001], NDD [SMD = 1.34, 95% CI (0.9, 1.78), p < 0.00001]. After roxadustat therapy, patients’ serum iron levels were considerably higher in the dialysis group than in the control group, but there was no significant change in the NDD group [SMD = 0.42, 95% CI (0.27, 0.57), p < 0.00001]. In the NDD group, hepcidin, ferritin, and transferrin saturation (TSAT) were significantly reduced after roxadustat treatment: Hepcidin [SMD = −1.59, 95% CI (−2.69, −0.49), p = 0.005], ferritin [SMD = −0.51, 95% CI (−0.72, 0.3) p < 0.00001], TSAT [SMD = −0.41, 95% CI (−0.62, 0.2), p < 0.0001]. In terms of safety, adverse events (AE) [SMD = 1.08, 95% CI (0.98, 1.18) p = 0.11] and serious adverse events (SAE) [SMD = 1.32, 95% CI (0.97, 1.9) p = 0.08] were not significantly different between the two groups.

Conclusion: Roxadustat can improve anemia in NDD patients with chronic kidney disease, and its short-term safety was comparable to that of the comparison group.

Prevalence and risk factors of microalbuminuria in patients with lacunar infarction

Objectives: To investigate the prevalence and risk factors for microalbuminuria in patients with lacunar infarction. Methods: 702 lacunar infarction patients and 234 controls were recruited in this study, the concentration of urinary albumin and clinical characteristics were collected for each participant. We analyzed the prevalence of microalbuminuria in lacunar infarction patients, as well as the risk factors of microalbuminuria in patients with lacunar infarction. Results: The prevalence of microalbuminuria in patients with lacunar infarction was 32.8%, which was significantly higher than that in controls (9.8%, P＜0.001). Multiple linear regression analysis indicated that age, alcohol abuse, fasting blood glucose, systolic blood pressure, and triglyceride were positively associated with albumin/creatinine ratio levels. Multiple logistic regression analysis indicated that age (odds ratio [OR] = 1.067, 95% confidence interval [CI] = 1.029 to 1.105), alcohol abuse (OR = 3.001, 95% CI = 1.668 to 5.398), fasting blood glucose (OR = 2.014, 95% CI = 1.794 to 2.260), and systolic blood pressure (OR = 1.033, 95% CI = 1.010 to 1.056) were the independent risk factors for microalbuminuria in acute lacunar infarction patients, with high sensitivity, specificity, positive predictive value, and negative predictive value. Receiver operating characteristic curve analysis showed that the area under the curve for age, systolic blood pressure, and fasting blood glucose were 0.618 (cutoff value, 63.5 years; sensitivity, 54.8%; and specificity, 62.9%), 0.736 (cutoff level, 149.5 mmHg; sensitivity, 78.3%; and specificity, 61.2%) and 0.893 (cutoff value, 7 mmol/L; sensitivity, 92.2%; and specificity, 86%), respectively. Conclusion: Lacunar infarction was associated with higher microalbuminuria prevalence. Age, alcohol abuse, fasting blood glucose, and systolic blood pressure were individually significant and correlated factors of microalbuminuria in patients with lacunar infarction. More attention should be provided to this group of patients.

Stroke risk and outcomes in patients with chronic kidney disease or end-stage renal disease: Two nationwide studies

Background and aims

Because the risk and outcomes of stroke in patients with chronic kidney disease (CKD) or end-stage renal disease (ESRD) were unclear, we evaluated these risks using a retrospective cohort study and a nested cohort study.

Methods

We used Taiwan’s National Health Insurance Research Database to identify 1378 patients aged ≥20 years who had ESRD in 2000–2004. An age- and sex-matched CKD cohort (n = 5512) and a control cohort (n = 11,024) were selected for comparison. Events of incident stroke were considered as outcome during the follow-up period in 2000–2013, and we calculated adjusted hazard ratios (HR) and 95% CIs of stroke associated with CKD or ESRD. We further used matching procedure with propensity score to estimate the risk of stroke for control group, CKD patients, and EDRD patients. A nested cohort study of 318,638 hospitalized stroke patients between 2000 and 2010 also was conducted to analyze the impact of CKD and ESRD on post-stroke mortality.

Results

Before propensity-score matching, the incidences of stroke for controls, CKD patients and ESRD patients were 6.57, 13.3, and 21.7 per 1000 person-years, respectively. Compared with control group, the adjusted HRs of stroke were 1.49 (95% CI, 1.32–1.68) and 2.39 (95% CI, 1.39–2.87) for people with CKD or ESRD respectively, and were significantly higher in both sexes and every age group. After propensity-score matching, the HRs of stroke for patients with CKD and ESRD were 1.51 (95% CI 1.24–1.85) and 2.08 (95% CI 1.32–3.26), respectively, during the follow-up period. Among hospitalized stroke patients, adjusted rate ratio (RR) of post-stroke mortality in CKD and ESRD cohorts were 1.44 (95% CI, 1.33–1.56) and 2.62 (95% CI, 2.43–2.82) respectively compared with control.

Conclusions

CKD and ESRD patient groups thus faced significantly higher risk of stroke and post-stroke mortality. Risk factor identification and preventive strategies are needed to minimize stroke risk and post-stroke mortality in these vulnerable patient groups.

Anemia increases the mortality risk in patients with stroke: A meta-analysis of cohort studies

The impact of anemia on the outcome of patients with stroke remains inconsistent. We performed a meta-analysis of cohort studies to assess the mortality risk in stroke patients with and without anemia. Systematic searches were conducted in the PubMed, China National Knowledge Infrastructure, Web of Science and Wanfang databases to identify relevant studies from inception to November 2015. The estimated odds ratio with a 95% confidence interval was pooled. subgroup analyses and sensitivity analyses were also conducted. We used Begg’s funnel plot and Egger’s test to detect the potential publication bias. Thirteen cohort studies with a total of 19239 patients with stroke were included in this meta-analysis. The heterogeneity among studies was slight (I² = 59.0%, P = 0.031). The results from a random-effect model suggest that anemia is associated with an increased mortality risk in patients with stroke (adjusted odds ratio = 1.39, 95% confidence interval: 1.22–1.58, P < 0.001). The subgroup analyses are consistent with the total results. This meta-analysis of 13 cohort studies finds that anemia increases the mortality risk in patients with stroke. Future studies should perform longer follow-up to confirm this finding and explore its possible mechanism.

Serum Uric Acid Levels and Outcomes After Acute Ischemic Stroke

Previous studies assessing the association between serum uric acid levels and neurological outcome after acute ischemic stroke reported conflicting results. A systematic review and meta-analysis were conducted to assess the impact of serum uric acid levels on outcome after acute ischemic stroke. Pubmed, Embase, Web of Science, and Google scholar were searched through September 26, 2014 to identify eligible published or unpublished studies on the association between serum uric acid levels and outcome after acute ischemic stroke. Hazard ratio (HR) for poor outcome or mean differences of serum uric acid levels with 95% confidence intervals (95% CIs) were pooled using meta-analysis. The primary outcome was occurrence of poor outcomes, while the secondary outcome was the mean differences of serum uric acid levels in patients with good or poor outcomes. Ten eligible studies with a total of 8131 acute ischemic stroke patients were included into the meta-analysis. Compared with low serum uric acid level, high serum uric acid level was associated better outcome after acute ischemic stroke (HR = 0.77, 95% CI 0.68-0.88, P = 0.0001). Sensitivity analysis further identified the prognostic role of serum uric acid levels on outcome after acute ischemic stroke. Patients with good outcomes had a higher serum uric acid level compared with those with poor outcome (mean difference = 30.61 μmol/L, 95% CI 20.13-41.08, P < 0.00001). There was no obvious risk of publication bias in the meta-analysis. This meta-analysis supports that serum uric acid level has a protective effect on neurological outcome after acute ischemic stroke. High uric acid level at the onset is a biomarker of better prognosis in patients with acute ischemic stroke.

A cohort study of patients with anemia on admission and fatality after acute ischemic stroke

Reduced blood hemoglobin levels may impair oxygen delivery to the brain and hinder neurological improvement. We prospectively registered consecutively hospitalized Chinese patients with acute ischemic stroke within 24 hours of symptom onset to investigate whether anemia on admission influences case fatality and functional outcome of acute ischemic stroke at 12 months. Anemia was defined as a blood hemoglobin level of < 120 g/L for women, and < 130 g/L for men. We also performed a meta-analysis of the current cohort and previously published studies. We included 1176 patients, of whom 351 patients (29.8%) had anemia. Age (odds ratio [OR]=1.02, 95% confidence interval [CI]: 1.01-1.03), history of hemorrhagic stroke (OR=3.34, 95% CI: 1.17-9.56), alcohol consumption (OR=0.59, 95% CI: 0.38-0.92), and estimated glomerular filtration rate < 60 mL/minute per 1.73 m(2) (OR=1.34, 95% CI: 1.00-1.80) were the independent predictors of anemia. After adjustment for potential confounders, anemia on admission was shown to be an independent predictor of death at discharge and at 12 months (OR=1.66, 95% CI, 1.08-2.56; OR=1.56, 95% CI, 1.05-2.31). A meta-analysis of six included studies involving 3810 participants confirmed that anemia on admission was an independent predictor of death at the end of follow-up (OR=1.67, 95% CI, 1.25-2.08). Further studies are required to confirm these findings.