Category: Nevin Manimala

Genet Epidemiol. 2021 May 19. doi: 10.1002/gepi.22385. Online ahead of print.

ABSTRACT

Recently, Mendelian Randomization (MR) has gained in popularity as a concept to assess the causal relationship between phenotypes in genetic association studies. An extension of standard MR methodology, the MR Steiger approach, has recently been developed to infer the causal direction between two phenotypes in prospective studies. Through simulation studies, we examined and quantified the ability of the MR Steiger approach to determine the causal direction between two phenotypes (i.e., effect direction). Through simulation studies, our results show that the MR Steiger approach may fail to correctly identify the direction of causality. This is true, especially in the presence of pleiotropy. We also applied the MR Steiger method to the COPDGene study, a case-control study of chronic obstructive pulmonary disease (COPD) in current and former smokers, to examine the role of smoking on lung function. We have created an R package on Github called reverseDirection which runs simulations for user-specified scenarios to examine when the MR Steiger approach can correctly determine the causal direction between two phenotypes in any user specified scenario. In summary, our results emphasize the importance of caution when the MR Steiger approach is used in to infer the direction of causality.

PMID:34008876 | DOI:10.1002/gepi.22385

Arq Bras Cardiol. 2021 May;116(5):959-967. doi: 10.36660/abc.20200115.

ABSTRACT

BACKGROUND: For patients with ST-segment elevation myocardial infarction (STEMI) that are suffering from subsequent coronary microvascular functional and structural obstruction (CMVO), no specific and definitive therapeutic approaches of attenuation have been proven valid in up-to-date large-scale tests, which highlights the urge to address its early recognition.

OBJECTIVES: This study aimed to compare the performance of two clinical risk scores with an objective measurement of CMVO during percutaneous coronary intervention (PCI) with STEMI.

METHODS: The Index of Microcirculatory Resistance (IMR) measurement was conducted and the baseline clinical and angiographic parameters were also recorded. The patients were divided into MO (Microvascular obstruction) or NMO (Non-microvascular obstruction) groups according to the post-procedure IMR value. The CMVO risk was evaluated for all participants by SAK and ATI predictive scores, respectively. Each system was calculated by summing the scores of all variables. The receiver operator characteristic (ROC) curves and the area under the curve (AUC) of two risk models were used to evaluate the discriminatory performance. An echocardiography was performed seven days after the procedure to evaluate left ventricular ejection fraction (LVEF). A two-sided P-value of <0.05 was considered statistically significant.

RESULTS: Among the 65 eligible STEMI patients, 48 patients were allocated in the NMO group and 17 in the MO group, with a CMVO incidence of 26.15%. There was no significant difference in the AUC between both scores. The LVEF evaluated for the NMO group was higher than that of MO group.

CONCLUSION: Both SAK and ATI scores performed well in estimating CMVO risk after primary PCI for STEMI patients.

PMID:34008822 | DOI:10.36660/abc.20200115

J Biomech Eng. 2021 May 19. doi: 10.1115/1.4051213. Online ahead of print.

ABSTRACT

The relationship between three-dimensional shape and patellofemoral mechanics is complicated. The Wiberg patella classification is a method of distinguishing shape differences in the axial plane of the patella that can be used to connect shape differences to observed mechanics. This study uses a statistical shape model to relate the Wiberg patella classification to patella height and investigates its role in force distribution within the patellofemoral joint. The Wiberg Type I patella is shortest and has a more symmetrical medial and lateral facet while the Type III patella is longest with a larger lateral facet compared to medial. We generated patellofemoral morphologies from the statistical shape model and integrated them into a musculoskeletal model with a twelve degrees-of-freedom knee. We simulated an overground walking trial with these morphologies and recorded patellofemoral mechanics and ligament forces. An increase in patellar ligament force corresponded with an increase in patella height. Wiberg Type III patellas had a sharper patella apex which related to lower ratios of quadriceps tendon forces to patellar ligament forces. The change in pivot point of the patella affects the ratio of forces as well as the patellofemoral reaction force. This study provides a better understating of how patella morphology affects fundamental patella mechanics which may help identify at-risk populations for pathology development.

PMID:34008841 | DOI:10.1115/1.4051213

Arq Bras Cardiol. 2021 May;116(5):879-886. doi: 10.36660/abc.20200231.

ABSTRACT

BACKGROUND: Body mass index (BMI) is the most commonly used index to categorize a person as obese or non-obese, which is subject to important limitations.

OBJECTIVE: To evaluate the direct effect of BMI on cardiovascular outcomes among participants without central obesity.

METHODS: This analysis included 14,983 males and females aged 45-75 years from the Atherosclerosis Risk in Communities Study (ARIC). BMI was measured as general obesity, and waist circumference (WC), waist-to-hip ratio (WHR) and hip circumference as central obesity. Targeted maximum likelihood estimation (TMLE) was used to estimate the total effects (TEs) and the controlled direct effects (CDEs). The proportion of TE that would be eliminated if all participants were non-obese regarding central obesity was computed using the proportion eliminated (PE) index. P <0.05 was considered statistically significant. Analyses were performed in the TMLE R package.

RESULTS: The risk of cardiovascular outcomes attributed to BMI was significantly reversed by eliminating WHR obesity (p<0.001). The proportion eliminated of BMI effects was more tangible for non-obese participants regarding WC (PE=127%; 95%CI (126,128)) and WHR (PE=97%; 95%CI (96,98)) for coronary heart disease (CHD), and WHR (PE=92%; 95%CI (91,94)) for stroke, respectively. With respect to sex, the proportion eliminated of BMI effects was more tangible for non-obese participants regarding WHR (PE=428%; 95%CI (408,439)) for CHD in males, and WC (PE=99%; 95%CI (89,111)) for stroke in females, respectively.

CONCLUSION: These results indicate different potential effects of eliminating central obesity on the association between BMI and cardiovascular outcomes for males and females. (Arq Bras Cardiol. 2021; 116(5):879-886).

PMID:34008807 | DOI:10.36660/abc.20200231

Arq Bras Cardiol. 2021 May;116(5):908-916. doi: 10.36660/abc.20190726.

ABSTRACT

BACKGROUND: In the last decade, the number of cardiac electronic devices has risen considerably and consequently the occasional need for their removal. Concurrently, the transvenous lead removal became a safe procedure that could prevent open-heart surgery.

OBJECTIVE: The primary objective of this study was to describe the successful performance and the complication rates of pacemaker removals in a Brazilian public hospital. Our secondary aim was to describe the variables associated to successes and complications.

METHODS: A retrospective case series was conducted in patients submitted to pacemaker removal in a Brazilian public hospital from January 2013 to June 2018. Removal, explant, extraction, success and complication rates were defined by the 2017 Heart Rhythm Society Guideline. Categorical variables were compared using x2 or Fisher’s tests, while continuous variables were compared by unpaired tests. A p-value of 0.05 was considered statistically significant.

RESULTS: Cardiac device removals were performed in 61 patients, of which 51 were submitted to lead extractions and 10 to lead explants. In total, 128 leads were removed. Our clinical success rate was 100% in the explant group and 90.2% in the extraction one (p=0.58). Major complications were observed in 6.6% patients. Procedure failure was associated to older right ventricle (p=0.05) and atrial leads (p=0,04). Procedure duration (p=0.003) and need for blood transfusion (p<0,001) were associated to more complications.

CONCLUSION: Complications and clinical success were observed in 11.5% and 91.8% of the population, respectively. Removal of older atrial and ventricular leads were associated with lower success rates. Longer procedures and blood transfusions were associated with complications.

PMID:34008813 | DOI:10.36660/abc.20190726

Arq Bras Cardiol. 2021 May;116(5):928-937. doi: 10.36660/abc.20190356.

ABSTRACT

BACKGROUND: Although non-ischemic troponin elevation is frequently seen in patients admitted to the emergency department (ED), consensus regarding its management is lacking.

OBJECTIVES: This study aimed to characterize patients admitted to the ED with non-ischemic troponin elevation and to identify potential mortality predictors in this population.

METHODS: This retrospective observational study included ED patients with a positive troponin test result between June and July of 2015. Patients with a clinical diagnosis of acute coronary syndrome (ACS) were excluded. Data on patient demographics and clinical and laboratory variables were extracted from medical records. Follow-up data were obtained for 16 months or until death occurred. The statistical significance level was 5%.

RESULTS: Troponin elevation without ACS was found in 153 ED patients. The median (IQR) patient age was 78 (19) years, 80 (52.3%) were female and 59(38.6%) died during follow-up. The median (IQR) follow-up period was 477(316) days. Survivors were significantly younger 76 (24) vs. 84 (13) years; p=0.004) and featured a higher proportion of isolated troponin elevation (without creatine kinase or myoglobin elevation) in two consecutive evaluations: 48 (53.9%) vs. 8 (17.4%), p<0.001. Survivors also presented a lower rate of antiplatelet treatment and same-day hospitalization. In the multivariate logistic regression with adjustment for significant variables in the univariate analysis, isolated troponin elevation in two consecutive evaluations showed a hazard ratio= 0.43 (95%CI 0.17-0.96, p=0.039); hospitalization, previous antiplatelet treatment and age remained independently associated with mortality.

CONCLUSIONS: Isolated troponin elevation in two consecutive measurements was a strong predictor of survival in ED patients with troponin elevation but without ACS.

PMID:34008817 | DOI:10.36660/abc.20190356

Cad Saude Publica. 2021 May 17;37(5):e00169020. doi: 10.1590/0102-311X00169020. eCollection 2021.

ABSTRACT

The Satisfaction with Life Scale (SWLS) was originally proposed in the English language to measure the individual’s overall perception in relation to life. The study aims to evaluate the psychometric properties of SWLS when applied to young adults and estimate the influence of demographic characteristics on life satisfaction, in a non-probabilistic sample of young adult individuals (18 to 35 years) of both sexes in Araraquara, São Paulo State, Brazil. We assessed the fit of SWLS to the data by confirmatory analysis, using the comparative fit index (CFI), Tucker-Lewis index (TLI), and standardized root mean square residual (SRMR). Reliability was estimated by the alpha ordinal coefficient and omega. Factor invariance was estimated by multigroup analysis, with CFI test of statistical difference (ΔCFI). Comparison of the mean scores on satisfaction with life according to sex, age, economic stratum, and employment status was performed with analysis of variance (ANOVA). Participation included 2,170 individuals (females: 67.8%; age: 22.09 years). The model’s fit to the different samples was adequate (CFI = 0.981-0.998; TLI = 0.962-0.996; SRMR = 0.026-0.040; omega = 0.842-0.869; alpha = 0.862-0.889). Strict invariance was seen for the target variables. Life satisfaction was greater among individuals in higher economic strata. The data obtained with SWLS were valid, reliable, and invariant between samples with different sex, age, economic strata, and employment status. Life satisfaction was greater among individuals from higher economic strata and did not differ by sex, age, or employment status.

PMID:34008787 | DOI:10.1590/0102-311X00169020

J Appl Oral Sci. 2021 May 17;29:e20200787. doi: 10.1590/1678-7757-2020-0787. eCollection 2021.

ABSTRACT

OBJECTIVE: To define the subgingival microbial profile associated with Stage II generalized periodontitis using next-generation sequencing and to determine the relative abundance of novel periodontal pathogens and bacterial complexes.

METHODOLOGY: Subgingival biofilm samples were collected from 80 subjects diagnosed with Stage II generalized periodontitis. Bacterial DNA was extracted, and 16S rRNA-based bacterial profiling via next-generation sequencing was carried out. The bacterial composition and diversity of microbial communities based on the age and sex of the patients were analyzed. The bacterial species were organized into groups: bacterial complexes (red, orange, purple, yellow, and green), novel periodontal pathogens, periodontal health-related species, and unclassified periodontal species. The results were analyzed and statistically evaluated.

RESULTS: The highest number of bacteria belonged to the phylum Bacteroidetes and Firmicutes. In terms of relative abundance, the orange complex represented 18.99%, novel bacterial species (Fretibacterium spp. and Saccharibacteria spp.) comprised 17.34%, periodontal health-related species accounted for 16.75% and unclassified periodontal species represented (Leptotrichia spp. and Selenomonas spp.) 15.61%. Novel periodontal pathogens had outweighed the periodontal disease-related red complex (5.3%). The one-sample z-test performed was statistically significant at p<0.05. The Beta diversity based on the unweighted UniFrac distance at the species level demonstrated a total variance of 15.77% based on age and 39.19% on sex, which was not statistically significant.

CONCLUSION: The bacterial species corresponding to the disease-related orange complex and novel periodontal pathogens are predominant in Stage II generalized periodontitis.

PMID:34008792 | DOI:10.1590/1678-7757-2020-0787

Arq Bras Cardiol. 2021 May;116(5):867-876. doi: 10.36660/abc.20190739.

ABSTRACT

BACKGROUND: In patients with acute myocardial infarction (MI), cardiogenic shock (CS), and multivessel disease (MVD) questions remain unanswered when it comes to intervention on non-culprit arteries.

OBJECTIVE: This article aims to 1) characterize patients with MI, CS and MVD included in the Portuguese Registry on Acute Coronary Syndromes (ProACS); 2) compare different revascularization strategies in the sample; 3) identify predictors of in-hospital mortality among these patients.

METHODS: Observational retrospective study of patients with MI, CS and MVD included in the ProACS between 2010 and 2018. Two revascularization strategies were compared: complete during the index procedure (group 1); and complete or incomplete during the index hospitalization (groups 2-3). The primary endpoint was a composite of in-hospital death or MI. Statistical significance was defined by a p-value <0.05.

RESULTS: We identified 127 patients with MI, CS, and MVD (18.1% in group 1, and 81.9% in groups 2-3), with a mean age of 7012 years, and 92.9% of the sample being diagnosed with ST-segment elevation MI (STEMI). The primary endpoint occurred in 47.8% of the patients in group 1 and 37.5% in group 2-3 (p = 0.359). The rates of in-hospital death, recurrent MI, stroke, and major bleeding were also similar. The predictors of in-hospital death in this sample were the presence of left ventricle systolic dysfunction on admission (OR 16.8), right bundle branch block (OR 7.6), and anemia (OR 5.2) (p ≤ 0.02 for both).

CONCLUSIONS: Among patients with MI, CS, and MVD included in the ProACS, there was no significant difference between complete and incomplete revascularization during the index hospitalization regarding the occurrence of in-hospital death or MI. (Arq Bras Cardiol. 2021; 116(5):867-876).

PMID:34008805 | DOI:10.36660/abc.20190739

Codas. 2021 May 14;33(3):e20190218. doi: 10.1590/2317-1782/20202019218. eCollection 2021.

ABSTRACT

PURPOSE: The aim of the study was to investigate the electroneurophysiological aspects of volunteers with temporomandibular disorders before and after performing isotonic exercises for pain relief and self-care guidelines.

METHODS: The study was a parallel controlled randomized controlled trial under protocol 1,680,920. The inclusion criteria were age between 18 and 60 years, muscle temporomandibular dysfunction with or without limitation of mouth opening and self-reported pain with scores between 4 and 10. The individuals were randomized into experimental group and control. Twenty-three volunteers participated in the study, most of then were female. Control group had 11 and experimental group 12 individuals. Dropouts occurred in both groups, two in the experimental group and three in the control group. Since there were an intergroup imbalance the power density was analysed just in experimental group. Electroencephalographic recording was performed before and after the interventions, using the 32-channel apparatus, with sample frequency of 600 Hz and impedance of 5 kΩ. The data were processed through the MATLAB computer program. The individual records filtered off-line, using bandpass between 0.5 and 50 Hz. Epochs of 1,710 ms were created and the calculation of the absolute power density calculated by means of the fast Fourier transform. The statistical approach was inferential and quantitative.

RESULTS: The alpha power density analyzed presented a difference, but not significant, when compared in the two moments.

CONCLUSION: According to this study, isotonic exercises performed to reduce pain provided a small increase in alpha power density in the left temporal, parietal and occipital regions.

PMID:34008769 | DOI:10.1590/2317-1782/20202019218