Tag: statistics

Neurosurg Focus. 2021 Oct;51(4):E9. doi: 10.3171/2021.7.FOCUS21333.

ABSTRACT

OBJECTIVE: Cervical fractures in patients with ankylosing spondylitis can have devastating neurological consequences. Currently, several surgical approaches are commonly used to treat these fractures: anterior, posterior, and anterior-posterior. The relative rarity of these fractures has limited the ability of surgeons to objectively determine the merits of each. The authors present an updated systematic review and meta-analysis investigating the utility of anterior surgical approaches relative to posterior and anterior-posterior approaches.

METHODS: After a comprehensive literature search of the PubMed, Cochrane, and Embase databases, 7 clinical studies were included in the final qualitative and 6 in the final quantitative analyses. Of these studies, 6 compared anterior approaches with anterior-posterior and posterior approaches, while 1 investigated only an anterior approach. Odds ratios and 95% confidence intervals were calculated where appropriate.

RESULTS: A meta-analysis of postoperative neurological improvement revealed no statistically significant differences in gross rates of neurological improvement between anterior and posterior approaches (OR 0.40, 95% CI 0.10-1.59; p = 0.19). However, when analyzing the mean change in neurological function, patients who underwent anterior approaches had a significantly lower mean change in postoperative neurological function relative to patients who underwent posterior approaches (mean difference [MD] -0.60, 95% CI -0.76 to -0.45; p < 0.00001). An identical trend was seen between anterior and anterior-posterior approaches; there were no statistically significant differences in gross rates of neurological improvement (OR 3.05, 95% CI 0.84-11.15; p = 0.09). However, patients who underwent anterior approaches experienced a lower mean change in neurological function relative to anterior-posterior approaches (MD -0.46, 95% CI -0.60 to -0.32; p < 0.00001). There were no significant differences in complication rates between anterior approaches, posterior approaches, or anterior-posterior approaches, although complication rates trended lower in patients who underwent anterior approaches.

CONCLUSIONS: The results of this review and meta-analysis demonstrated the varying benefits of anterior approaches relative to posterior and anterior-posterior approaches in treatment of cervical fractures associated with ankylosing spondylitis. While reports demonstrated lower degrees of neurological improvement in anterior approaches, they may benefit patients with less-severe injuries if lower complication rates are desired.

PMID:34598150 | DOI:10.3171/2021.7.FOCUS21333

J Neurosurg. 2021 Oct 1:1-11. doi: 10.3171/2021.3.JNS204378. Online ahead of print.

ABSTRACT

OBJECTIVE: Visual deterioration after endoscopic endonasal transsphenoidal surgery (EETS) for sellar and parasellar masses is a rare but serious complication caused by either compressive or ischemic mechanisms. Timely diagnosis and intervention may restore vision if instituted appropriately. The associated risk factors and their relation to the success of intervention are not well understood.

METHODS: The authors examined a series of 1200 consecutive EETS cases performed by the senior author at Weill Cornell/NewYork-Presbyterian Hospital from 2010 to 2020. Cases with postoperative visual deterioration were identified. Pre- and postoperative clinical data, mechanism of visual decline, latency to intervention, and long-term visual outcome were retrospectively collected and analyzed with appropriate statistical methods.

RESULTS: Twenty-one patients (1.75%) complained of early postoperative visual deterioration. The most common pathology associated with postoperative visual loss was craniopharyngioma (7.69%), followed by meningioma (5.43%) and then pituitary adenoma (1.94%). Timely intervention restored vision in 81% of patients for a 0.33% rate of permanent visual deterioration. Average time to visual deterioration was 28.8 hours, and over 70% of patients experienced vision loss within the first 13 hours. Compressive etiology (n = 11), consisting of either hematoma (n = 8) or graft displacement (n = 3), occurred 7.3 hours and 70.3 hours after surgery, respectively, and was more common in adenomas. Acute postoperative visual deterioration was more common in firm closures (4.78%) compared with soft closures (1.03%; p = 0.0006). Ischemic etiology (n = 10) occurred 10.3 hours after surgery and was more common with craniopharyngiomas and meningiomas (p = 0.08). Sixteen patients (76.2%) underwent early reoperation to explore and decompress the optic apparatus. Vision was restored to baseline after reoperation in all 11 compressive cases, whereas 6/10 ischemic cases improved with supplemental oxygen and hypervolemic hypertensive therapy (p = 0.02). Fluid expansion from 8 to 16 hours (p = 0.034) and systolic blood pressure elevation from 32 to 48 hours (p = 0.05) after surgery were significantly higher in those ischemic patients who recovered some vision compared with those with persistent visual deficits.

CONCLUSIONS: Visual deterioration after EETS is a rare event but can be effectively treated if acted upon appropriately and in a timely fashion. Compressive etiology is reversible with early reoperation. Ischemic etiology can be successfully treated in roughly half of cases with supplemental oxygen and hypertensive hypervolemic therapy but may result in permanent visual deterioration if not instituted appropriately or if delayed with unnecessary exploratory surgery.

PMID:34598134 | DOI:10.3171/2021.3.JNS204378

Ultrasonics. 2021 Sep 20;119:106585. doi: 10.1016/j.ultras.2021.106585. Online ahead of print.

ABSTRACT

Grain boundary scattering-induced attenuation and phase-velocity dispersion of Rayleigh-type surface acoustic waves are studied with a time-domain finite-element method (FEM). The FEM simulation incorporates a realistic material model based on matching the spatial two-point correlation function of a Laguerre tessellation with that obtained from optical micrographs of a previously studied aluminum sample. Plane surface acoustic waves are excited in a multitude of statistically equivalent virtual polycrystals, and their surface displacement fields are averaged for subsequent extraction of the coherent-wave attenuation coefficient and phase velocity. Comparisons to previous laser-ultrasonic experiments, an analytical mean-field model, and the FEM results show good agreement in a broad frequency range from about 10 to 130MHz. Observed discrepancies between models and measurement reveal the importance of spatial averaging in the context of mean-field approaches and suggest improvement strategies for future experimental studies and advanced analytical models. A different attenuation power law for Rayleigh waves is found in the stochastic scattering regime compared to bulk acoustic waves.

PMID:34598096 | DOI:10.1016/j.ultras.2021.106585

Drug Alcohol Depend. 2021 Aug 28;228:108977. doi: 10.1016/j.drugalcdep.2021.108977. Online ahead of print.

ABSTRACT

BACKGROUND: Although national syndromic surveillance data reported declines in emergency department (ED) visits after the declaration of the national stay-at-home order for COVID-19, little is known whether these declines were observed for suspected opioid overdose.

METHODS: This interrupted time series study used syndromic surveillance data from four states participating in the HEALing Communities Study: Kentucky, Massachusetts, New York, and Ohio. All ED encounters for suspected opioid overdose (n = 48,301) occurring during the first 31 weeks of 2020 were included. We examined the impact of the national public health emergency for COVID-19 (declared on March 14, 2020) on trends in ED encounters for suspected opioid overdose.

RESULTS: Three of four states (Massachusetts, New York and Ohio) experienced a statistically significant immediate decline in the rate of ED encounters for suspected opioid overdose (per 100,000) after the nationwide public health emergency declaration (MA: -0.99; 95 % CI: -1.75, -0.24; NY: -0.10; 95 % CI, -0.20, 0.0; OH: -0.33, 95 % CI: -0.58, -0.07). After this date, Ohio and Kentucky experienced a sustained rate of increase for a 13-week period. New York experienced a decrease in the rate of ED encounters for a 10-week period, after which the rate began to increase. In Massachusetts after a significant immediate decline in the rate of ED encounters, there was no significant difference in the rate of change for a 6-week period, followed by an immediate increase in the ED rate to higher than pre-COVID levels.

CONCLUSIONS: The heterogeneity in the trends in ED encounters between the four sites show that the national stay-at-home order had a differential impact on opioid overdose ED presentation in each state.

PMID:34598100 | DOI:10.1016/j.drugalcdep.2021.108977

Comput Biol Med. 2021 Sep 17;138:104866. doi: 10.1016/j.compbiomed.2021.104866. Online ahead of print.

ABSTRACT

With the increasing number of samples, the manual clustering of COVID-19 and medical disease data samples becomes time-consuming and requires highly skilled labour. Recently, several algorithms have been used for clustering medical datasets deterministically; however, these definitions have not been effective in grouping and analysing medical diseases. The use of evolutionary clustering algorithms may help to effectively cluster these diseases. On this presumption, we improved the current evolutionary clustering algorithm star (ECA*), called iECA*, in three manners: (i) utilising the elbow method to find the correct number of clusters; (ii) cleaning and processing data as part of iECA* to apply it to multivariate and domain-theory datasets; (iii) using iECA* for real-world applications in clustering COVID-19 and medical disease datasets. Experiments were conducted to examine the performance of iECA* against state-of-the-art algorithms using performance and validation measures (validation measures, statistical benchmarking, and performance ranking framework). The results demonstrate three primary findings. First, iECA* was more effective than other algorithms in grouping the chosen medical disease datasets according to the cluster validation criteria. Second, iECA* exhibited the lower execution time and memory consumption for clustering all the datasets, compared to the current clustering methods analysed. Third, an operational framework was proposed to rate the effectiveness of iECA* against other algorithms in the datasets analysed, and the results indicated that iECA* exhibited the best performance in clustering all medical datasets. Further research is required on real-world multi-dimensional data containing complex knowledge fields for experimental verification of iECA* compared to evolutionary algorithms.

PMID:34598065 | DOI:10.1016/j.compbiomed.2021.104866

Leuk Res. 2021 Sep 25;110:106715. doi: 10.1016/j.leukres.2021.106715. Online ahead of print.

ABSTRACT

BACKGROUND: The prognostic value of platelet count in diffuse large B-cell lymphoma (DLBCL) has not been extensively investigated. We aimed to examine the association of pretreatment platelet count with disease features, and further examine the prognostic significance of platelet count in DLBCL treated with the R-CHOP regimen.

METHODS: Patients with DLBCL diagnosed between Jan 1 st, 2005 and Dec 31 st, 2018 at Cancer Hospital, Chinese Academy of Medical Sciences were retrospectively analyzed. Propensity score matching (PSM) was used to balance confounding factors.

RESULTS: A total of 1007 eligible patients who received frontline R-CHOP or R-CHOP-like regimens were included in this study. The optimal cutoff value of platelet count was 157 × 10⁹/L, as determined by the Maximally Selected Rank Statistics method. Patients with the platelet count ≤157 × 10⁹/L had significantly inferior overall survival (OS) (5-year OS, 44.4 % vs. 74.9 %, P < 0.001) and progression-free survival (PFS) (5-year PFS, 35.5 % vs. 65.9 %, P < 0.001) than those with the platelet count >157×10⁹/L. Multivariate analyses showed that pretreatment platelet count ≤ 157 × 10⁹/L was an adversely independent prognostic factor for OS (hazard ratio [HR] 1.960, 95 % confidence interval [CI] 1.418-2.709, P<0.001) and PFS (HR 1.443, 95 %CI 1.080-1.927, P = 0.013). The PSM analysis and subgroup analyses further confirmed the significantly negative impact of low platelet count on OS and PFS.

CONCLUSION: The pretreatment platelet count may be a simple, cost-effective and useful prognostic factor in DLBCL patients treated with frontline R-CHOP regimens. Further investigation is warranted to elucidate the biologic mechanism underlying the prognostic significance of platelet count in DLBCL.

PMID:34598076 | DOI:10.1016/j.leukres.2021.106715

Horm Behav. 2021 Sep 28;136:105063. doi: 10.1016/j.yhbeh.2021.105063. Online ahead of print.

ABSTRACT

Contemporary moral psychology explores the biological underpinnings of morality, including how neuromodulators influence moral judgment and decision making. Some studies suggest that higher circulating testosterone is associated with increased acceptance of sacrificial harm, such as killing one person to save five lives, consistent with utilitarian ethics and inconsistent with deontological ethics. However, most studies employ conventional analytic techniques that conflate concern about outcomes with reduced concern about sacrificial harm, many are statistically underpowered, and none examine potential regulating effects of cortisol. Therefore, we examined whether salivary concentrations of testosterone and cortisol jointly predict sacrificial dilemma judgments among a large sample of undergraduates (n = 199). We utilized an advanced cognitive modeling technique (process dissociation) to independently assess sensitivity to causing harm and maximizing outcomes, preregistering the prediction that higher testosterone would predict reduced harm-rejection rather than increased concern for outcomes, especially among people low in cortisol. However, neither testosterone, nor cortisol, nor their interaction predicted sacrificial dilemma response tendencies. Such findings raise questions about the robustness of past evidence suggesting links between testosterone and sacrificial dilemma judgments.

PMID:34598057 | DOI:10.1016/j.yhbeh.2021.105063

Cancer Treat Res Commun. 2021 Sep 25;29:100464. doi: 10.1016/j.ctarc.2021.100464. Online ahead of print.

ABSTRACT

INTRODUCTION: Cutaneous malignant melanoma (CMM) incidence has risen rapidly in the last 50 years. Poor progression and high mortality characterize CMM, making a thorough understanding of progression and associated factors essential for optimizing care.

AIMS: We assessed the association between the Neutrophil-to-Lymphocyte Ratio (NLR) and mortality in adults with CMM from an entirely mixed-race Hispanic population during 12 consecutive years of extensive follow-up.

MATERIAL & METHODS: We performed a retrospective cohort study in a tertiary hospital in Peru. NLR was categorized with a cutoff value higher or equal than 3. We collected demographic variables, laboratory results and treatments at baseline of follow-up. Cox regression analysis was performed, and we calculated crude and adjusted hazard ratios (HR) and their 95% confidence interval (95%CI).

RESULTS: The analysis was from 615 CMM cases, and there were 378 deaths. Most melanomas (63.6%) were acral lentiginous. The crude analysis showed that high NLR is a risk factor for mortality, HR = 2.52; 95%CI (2.03-3.14). High NRL ratio remains statistically significant after adjusting for confounding variables, aHR = 1.61; 95%CI (1.16-2.24). Other risk factors for mortality were clinical stages III and IV, older than 60 years, females and greater Breslow thickness.

CONCLUSIONS: We concluded that high NRL ratio is a risk factor for mortality and should be monitored in every patient who is diagnosed with malignant melanoma during their first blood count. It should then be carried out in follow-up controls for patients of clinical stage III and IV only, or in patients who present a relapse.

PMID:34598061 | DOI:10.1016/j.ctarc.2021.100464

J Psychosom Res. 2021 Sep 25;150:110629. doi: 10.1016/j.jpsychores.2021.110629. Online ahead of print.

ABSTRACT

BACKGROUND: The aims of this study were to investigate the stability of alexithymia from adolescence to young adulthood, as well as the association between alexithymia, peer relationships, and symptoms of depression and dissociation.

METHODS: The participants (n = 755, aged 13-18 years) were assessed with self-rated questionnaires and the 20-item Toronto Alexithymia Scale (TAS-20) at baseline in 2005 and on follow-up in 2011.

RESULTS: The changes in the TAS-20 total score (t = -12.26) and the scores for its subscales, difficulty identifying feelings (DIF) (t = -4.04), difficulty describing feelings (DDF) (t = -5.10), and externally oriented thinking (EOT) (t = -18.23), were statistically significant (p < 0.001). Effect sizes (Cohen’s d) for the change indicating absolute stability were small for DIF (-0.15) and DDF (-0.19), medium for TAS-20 total (-0.45), and large for EOT (-0.66) scores. Moderate correlations in test-retests with Spearman’s ρ (TAS-20 total 0.46, DIF 0.41, DDF 0.39, EOT 0.43) indicated relative stability, whereas low intraclass correlation coefficients (ICCs) (respectively 0.41, 0.39, 0.37, 0.37) indicated poor reliability of test-retests. In regression analyses, poor relationships with peers, loneliness, and symptoms of depression and dissociation at baseline associated with alexithymia at baseline and on follow-up. Unlike EOT, increases in the TAS-20 total, DIF, and DDF scores during the 6-year follow-up associated with baseline symptoms of depression and dissociation.

CONCLUSIONS: Alexithymia in adolescence is not always a reliable predictor of alexithymia in young adulthood. Mental health symptoms appear to affect the consistency of alexithymia during adolescent development.

PMID:34598049 | DOI:10.1016/j.jpsychores.2021.110629

J Neurol Sci. 2021 Sep 27;430:120009. doi: 10.1016/j.jns.2021.120009. Online ahead of print.

ABSTRACT

INTRODUCTION: Parkinson’s disease (PD) ranks the second most common neurodegenerative disease. Aside from genetic predisposition, many external factors such as traumatic brain injury and exposure of substances including pesticides also contribute to PD’s pathogenesis. Many previous studies observed the association between the use of β-adrenoceptor acting agents and risk of PD.

OBJECTIVE: To conduct systematic review and meta-analysis to summarize whether the use of β-agonist and β-antagonist agents were associated with risk of PD.

METHOD: We independently searched for published studies from EMBASE and MEDLINE databases from inception to February 2021. This meta-analysis includes 9 case-control studies and 1 cohort study meeting the eligibility criteria, with a total of 380,105 participants.

RESULTS: Overall β-antagonists use appeared to associate with increase PD risk with an odd ratio (OR) of 1.2 (95% CI 1.07-1.34). Propranolol and metoprolol had a statistically significant association with higher risk of PD: pooled OR was 1.67 (95% CI 1.22-2.29) and 1.07 (95% CI 1.03-1.1), respectively. On the other hand, β-agonists significantly inverse association with PD risk with OR of 0.88 (95% CI 0.85-0.92). Salbutamol unexpectedly showed no statistical significance in reduced risk of PD with a pooled risk ratio of 1.0 (95% CI 0.87-1.16).

CONCLUSION: Overall β-antagonists, including propranolol and metoprolol, were associated with an increased risk of PD, in contrast to β-agonists, which were associated with decreased the risk.

PMID:34598055 | DOI:10.1016/j.jns.2021.120009