Association between serum cystatin C levels and the severity or potential risk factors of acute ischemic stroke.

OBJECTIVE: We sought to investigate whether serum cystatin C levels are correlated with either stroke severity or with potential risk factors of acute ischemic stroke. METHODS: 171 patients with acute ischemic stroke and 99 control subjects with minor, unrelated diseases with stroke were included in this retrospective study. Serum cystatin C levels were determined in all subjects. Serum concentrations of several vascular risk factors in stoke patients were determined by biochemical assays. The severity of strokes was scored via the National Institutes of Health Stroke Scale (NIHSS). RESULTS: Serum cystatin C levels were significantly increased in patients with acute ischemic stroke compared with control subjects (1.26 ± 0.34 mg/L vs. 0.78 ± 0.24 mg/L, p < 0.001).When analyzed in quartiles of serum cystatin C levels, concentrations were low (<0.75 mM) for 5 stroke patients (2.92%), intermediate (0.75-1 mM) for 42 patients (24.56%), high (1-1.25 mM) for 45 patients (26.32%), and very high (>1.25 mM) for 79 patients (46.20%). However, serum cystatin C levels were not correlated with NIHSS scores, serum total cholesterol, high-density lipoprotein, low-density lipoprotein, apolipoprotein a, or apolipoprotein b levels. Further, serum cystatin C concentrations in stroke patients were not correlated with the presence of intracranial arterial stenosis, hypertension, or diabetes. CONCLUSION: Our study suggests that there is a close relationship between cystatin C and acute ischemic stroke, independently of conventional risk factors. But the levels of cystatin C are not correlated with the stroke severity.

Changes in Olfactory Bulb Volume in Parkinson's Disease: A Systematic Review and Meta-Analysis.

OBJECTIVE: The changes in olfactory bulb (OB) volume in Parkinson's disease (PD) patients have not yet been comprehensively evaluated. The purpose of this meta-analysis was to explore whether the OB volume was significantly different between PD patients and healthy controls. METHODS: PubMed and Embase were searched up to March 6, 2015 with no language restrictions. Two independent reviewers screened eligible studies and extracted data on study characteristics and OB volume. Additionally, a systematic review and meta-analysis using a random-effects model were conducted. Publication bias was determined by using funnel plots and Begg's and Egger's tests. Subgroup analyses were performed to assess possible sources of heterogeneity. RESULTS: Six original case-control studies of 216 PD patients and 175 healthy controls were analyzed. The pooled weighted mean difference (WMD) in the OB volume between the PD patients and the healthy participants was -8.071 for the right OB and -10.124 for the left OB; these values indicated a significant difference among PD patients compared with healthy controls. In addition, a significant difference in the lateralized OB volume was observed in PD patients, with a pooled WMD of 1.618; these results indicated a larger right OB volume than left OB volume in PD patients. In contrast, no difference in the lateralized OB volume was found in healthy controls. No statistical evidence of publication bias among studies was found based on Egger's or Begg's tests. Sensitivity analyses revealed that the results were consistent and robust. CONCLUSIONS: Overall, both the left and the right OB volume were significantly smaller in PD patients than in healthy controls. However, significant heterogeneity and an insufficient number of studies underscore the need for further observational research.