Predictors of Citations in Neurosurgical Research: A 5-Year Follow-Up.

BACKGROUND: Citation rates are an important measure for the impact of articles. This study is the most comprehensive analysis of predictors for scientific neurosurgical research articles. METHODS: Scientific articles published in 13 neurosurgical journals in 2015 were selected. Data collected included article subject, level of evidence (LOE), journal impact factor (IF), authorship, contributing centers, and study design. Citation counts were collected for each article in Web of Science (WoS) and Google Scholar (GS) 2.5 and 5 years after publication and Scopus 5 years after publication. A generalized linear mixed-effects model using the predictors of search engine, LOE, number of centers, number of authors, and IF was constructed to predict total citation count at 5 years. RESULTS: A total of 2867 articles generated 39,190 citations in WoS, 61,682 in GS, and 43,481 in Scopus. The median number of citations per article was 10 (interquartile range [IQR], 14) in WoS, 15 (IQR, 20) in GS, and 11 (IQR, 15) in Scopus. On average, for every 1 citation in WoS, Scopus and GS identified 1.11 and 1.58 citations, respectively. Significant predictors of citation count in all databases 5 years after publication included search engine, LOE, number of centers, number of authors, number of countries, journal IF, and the month of publication (P < 0.05). The article subject (e.g., tumor or spine) did not significantly predict citation counts. CONCLUSIONS: In the most thorough analysis of citation predictors in the neurosurgical literature, search engine, LOE, number of centers, number of authors, number of countries, journal impact factor, and month of publication influenced citations 5 years after publication.

Predictors of Citations in Neurosurgical Research.

OBJECTIVE: The number of citations an article receives is an important measure of impact for published research. There are limited published data on predictors of citations in neurosurgery research. We aimed to analyze predictors of citations for neurosurgical articles. METHODS: All articles published in 14 neurosurgical journals in the year 2015 were examined and data collected about their features. The number of citations for each article was tallied using both Web of Science (WoS) and Google Scholar (GS) 2.5 years after their publication in print. Negative binomial regression was then performed to determine the relationship between article features and citation counts for scientific articles. RESULTS: A total of 3923 articles were analyzed, comprising 2867 scientific articles (72.6%) and 1056 nonscientific (editorial, commentary, etc.) articles (27.4%). At 2.5 years, scientific articles had a median [interquartile range] number of citations per article of 3.0 [6.0] and 7.0 [9.0] found in WoS and GS, respectively; nonscientific articles had accumulated median 0.0 [2.0] in both WOS and GS. Articles with the study topic "Spine" had the highest citation count at 4.0 [5.0] and 8.0 [10.0] in WoS and GS, respectively. Significant predictors of citation count in scientific articles were level of evidence, number of centers, number of authors, and impact factor. CONCLUSIONS: This is the largest investigation analyzing predictors of citations in the neurosurgical literature. Factors found to be most influential on citation rates in scientific articles included the study's level of evidence, number of participating centers, number of authors, and the publishing journal's impact factor.

Utility of cerebrospinal fluid lactate in aneurysmal subarachnoid hemorrhage.

BACKGROUND: An external ventricular drain (EVD) treats hydrocephalus in patients with aneurysmal subarachnoid hemorrhage (aSAH). This study examines the utility of cerebrospinal fluid (CSF) lactate collected from an EVD as a proposed biomarker to predict patient outcome and vasospasm/delayed cerebral ischemia. METHODS: Consecutive adults admitted to Wake Forest Baptist Medical Center from 2010 to 2015 with aSAH were identified through the electronic medical record, and clinical variables were collected and analyzed for correlation with incidence of vasospasm and discharge outcome. RESULTS: In all, 51 patients with aSAH and an EVD had CSF lactate measured which ranged from 1.9 to 6.2 mmol/L, with a median value of 3.2 mmol/L. Vasospasm based on transcranial Doppler assessment occurred in 29 patients (57%), of which 20 (45%) were clinically symptomatic. Good outcome (discharge to home/acute rehab) occurred in 35 patients (69%). Sixteen patients (31%) had an unfavorable outcome (died/discharged to nursing homes/long-term acute care facility). In multivariate regression analysis, unfavorable outcome at discharge (P = 0.02), elevated CSF protein (P = 0.04), and admission Hunt and Hess score 3-5 (P = 0.05) were significantly associated with higher CSF lactate. The risk of symptomatic vasospasm increased with lactate in univariate analysis, but did not reach statistical significance (P = 0.077). CONCLUSION: The measurement of the CSF biochemical markers using an EVD is feasible and safe. We found that elevated CSF lactate correlates with patient outcome. Larger prospective studies are needed to test the validity of this finding and for understanding the underlying pathophysiologic mechanisms.

A multicenter study evaluating the frequency and time requirement of mechanical thrombectomy.

INTRODUCTION: There are few published data evaluating the incidence of mechanical thrombectomy among stroke centers or the times at which they occur. METHODS: A multicenter retrospective study was performed to identify all patients undergoing emergent thrombectomy for acute ischemic stroke during a 3-month period (June through August 2016). Consultations that did not undergo thrombectomy were not included. RESULTS: Ten institutions participated in the study. During the 92-day study period, a total of 189 patients underwent mechanical thrombectomy. The average number of procedures per hospital over the study period was 18.9 (average of 0.2 cases per day per or 75.6 cases per year). This ranged from 0.09 cases per day at the lowest volume center to 0.49 cases per day at the highest volume center. Procedures were more common on weekdays (p<0.001) and during non-work hours (p<0.001). The most common period for thrombectomy procedures was between 20:00 and 21:00 hours. The median time from notification to groin puncture was 84 min (IQR 56-145 min) and from puncture to closure was 57 min (IQR 33-80 min). The median time from imaging completion to procedural start was 52 min longer for non-work hours than during work hours (p<0.001). There were no differences in procedural length based on day of the week or time of day. CONCLUSIONS: These findings indicate that the majority of mechanical thrombectomy cases occur during non-work hours, with associated off-hours delays, which has important operational implications for hospitals implementing stroke call coverage.

A Pilot Study of the Level of Evidence and Collaboration in Published Neurosurgical Research.

OBJECTIVE: Large-scale studies analyzing neurosurgical published research are lacking. This pilot study was designed to assess feasibility of an ongoing annual neurosurgical literature and research analysis of published articles in English-language neurosurgery journals. METHODS: All scientific articles published during 2015 in the print version of 14 English-language neurosurgery journals were reviewed individually. RESULTS: During 2015, 4065 articles were published in 14 neurosurgical journals. Of these, 1116 (27.5%) were nonscientific articles and were excluded from the analysis, and 2949 scientific articles were analyzed. Of these, 2% and 8.5% of publications met criteria for levels of evidence 1 and 2, respectively. One third of published manuscripts (33.2%) were retrospective chart reviews. There were 1742 different centers (mean 1.95 centers per article; range, 1-19) represented in 2949 articles from 67 countries (mean 1.23 countries per article; range, 1-12). Multicenter collaboration was present in 47.5% of published articles, and international collaboration was present in 17.5%. The highest numbers of U.S. author international collaborations were with Canada (70 collaborations), China (33 collaborations) and Italy (25 collaborations). Data for levels of evidence, multicenter collaborations, and international collaborations are presented for each individual journal and subject within neurosurgery. CONCLUSIONS: This pilot analysis provides a descriptive assessment of levels of evidence and collaboration based on journal, general subject matter, and subcategories of subject allowing for comparison. This methodology may be used on an annual basis to establish neurosurgery publication trends and to identify underrepresented areas of research within the specialty.

Psoriasis, Depression, and Inflammatory Overlap: A Review.

Psoriasis has an enormous impact on patients' lives and is frequently associated with depression. Depression in psoriasis may be attributed, at least in part, to elevated proinflammatory cytokines rather than the psychosocial impact of psoriasis itself. Biologics that target inflammatory cytokines treat the clinical manifestations of psoriasis, but may also play a role in reducing associated depression. Multiple biologics have decreased symptoms of depression during clinical trials in psoriasis; however, these studies used a variety of depression screening tools, which limits comparison. Furthermore, it is difficult to distinguish whether improved depression is the result of the direct anti-inflammatory effect of the biologic, or the indirect effect of improved psoriasis leading to better psychological status. Future studies evaluating depression in patients with psoriasis could benefit from a standardized depression screening tool to mitigate discrepancies and facilitate comparison across treatment types. Here, we highlight the inflammatory overlap between psoriasis and depression by examining the pathophysiology of depression, and reviewing psoriasis clinical studies that assessed depression as an outcome measure.