Tag: statistics

J Gerontol A Biol Sci Med Sci. 2021 Nov 10:glab339. doi: 10.1093/gerona/glab339. Online ahead of print.

ABSTRACT

BACKGROUND: Several guidelines have suggested alternative glycemic markers for hemoglobin A1c among older adults with limited life expectancy or multiple coexisting chronic illnesses. We evaluated associations between fructosamine, albumin-corrected fructosamine (AlbF) and fasting plasma glucose (FPG) and mortality in the diabetic and non-diabetic subpopulations, compared which marker better predicts mortality among participants aged 80 and above.

METHODS: Included were 2,238 subjects from the Healthy Ageing and Biomarkers Cohort Study (2012-2018) and 207 participants had diabetes at baseline. Multivariable Cox proportional hazards regression models investigated the associations of fructosamine, AlbF, FPG and all-cause, cardiovascular disease (CVD), and non-CVD mortality in the diabetic and non-diabetic subpopulations. Restricted cubic splines (RCS) explored potential non-linear relations. C-statistic, integrated discrimination improvement (IDI) and net reclassification improvement (NRI) evaluated the additive value of different glycemic markers to predict mortality.

RESULTS: Overall, 1,191 deaths were documented during 6,793 person-years of follow-up. In the linear model, per unit increases of fructosamine, AlbF and FPG were associated with higher risk of mortality in non-diabetic participants, with hazard ratios of 1.02 (1.00, 1.05), 1.27 (1.14, 1.42) and 1.04 (0.98, 1.11) for all-cause mortality, and 1.04 (1.00, 1.07), 1.38 (1.19, 1.59) and 1.10 (1.01, 1.19) for non-CVD mortality, respectively. Comparisons indicated AlbF better predicts all-cause and non-CVD mortality in non-diabetic participants with significant improvement in IDI and NRI.

CONCLUSIONS: Higher concentrations of fructosamine, AlbF, and FPG were associated with higher risk of all-cause or non-CVD mortality among very elderly where AlbF may constitute an alternative prospective glycemic predictor of mortality.

PMID:34758092 | DOI:10.1093/gerona/glab339

Mod Rheumatol. 2021 Sep 20:roab009. doi: 10.1093/mr/roab009. Online ahead of print.

ABSTRACT

OBJECTIVES: Previous studies suggest that exposure to inflammation in infancy may increase the risk for attention-deficit and hyperactivity disorder (ADHD). We studied the ADHD manifestations among 124 familial Mediterranean fever (FMF) patients and examined the relationship between FMF patient characteristics and ADHD.

METHODS: Clinical, demographic, and genetic data were abstracted from patients’ medical records and supplemented by information obtained during clinic visits. ADHD manifestations were assessed using the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) questionnaire.

RESULTS: ADHD was diagnosed in 42 (32.8%) FMF patients, a rate significantly higher than in unselected populations (∼8%). A majority (n = 27, 64.3%) had combined inattentive, hyperactive-impulsive manifestations. Eight (19%) had predominantly hyperactive-impulsive, and seven (16.6%) had predominantly inattentive symptoms. FMF patients with severe manifestations reported more ADHD symptoms. FMF patients with ADHD symptoms were less adherent to their treatment regimen, with only 61.9% of the patients with ADHD symptoms adhering to colchicine therapy compared to 92.7% of the patients without ADHD symptoms.

CONCLUSION: The high prevalence of ADHD characteristics in children with FMF may support the neuroimmune hypothesis that chronic inflammation increases the risk for ADHD. Children with FMF should be screened for ADHD as its presence may adversely affect adherence to treatment.

PMID:34758078 | DOI:10.1093/mr/roab009

PLoS One. 2021 Nov 10;16(11):e0259574. doi: 10.1371/journal.pone.0259574. eCollection 2021.

ABSTRACT

INTRODUCTION: Rheumatoid arthritis(RA) and osteoarthritis(OA) patients showed systemic manifestations that may lead to a reduction in muscle strength, muscle mass and, consequently, to a reduction in functionality. On the other hand, moderate intensity resistance training(MIRT) and high intensity resistance training(HIRT) are able to improve muscle strength and muscle mass in RA and OA without affecting the disease course. However, due to the articular manifestations caused by these diseases, these patients may present intolerance to MIRT or HIRT. Thus, the low intensity resistance training combined with blood flow restriction(LIRTBFR) may be a new training strategy for these populations.

OBJECTIVE: To perform a systematic review with meta-analysis to verify the effects of LIRTBFR on muscle strength, muscle mass and functionality in RA and OA patients.

MATERIALS AND METHODS: A systematic review with meta-analysis of randomized clinical trials(RCTs), published in English, between 1957-2021, was conducted using MEDLINE(PubMed), Embase and Cochrane Library. The methodological quality was assessed using Physiotherapy Evidence Database scale. The risk of bias was assessed using RoB2.0. Mean difference(MD) or standardized mean difference(SMD) and 95% confidence intervals(CI) were pooled using a random-effects model. A P<0.05 was considered statistically significant.

RESULTS: Five RCTs were included. We found no significant differences in the effects between LIRTBFR, MIRT and HIRT on muscle strength, which was assessed by tests of quadriceps strength(SMD = -0.01[-0.57, 0.54], P = 0.96; I² = 58%) and functionality measured by tests with patterns similar to walking(SMD = -0.04[-0.39, 0.31], P = 0.82; I² = 0%). Compared to HIRT, muscle mass gain after LIRTBFR was reported to be similar. When comparing LIRTBFR with low intensity resistance training without blood flow restriction(LIRT), the effect LIRTBFR was reported to be higher on muscle strength, which was evaluated by the knee extension test.

CONCLUSION: LIRTBFR appears to be a promising strategy for gains in muscle strength, muscle mass and functionality in a predominant sample of RA and OA women.

PMID:34758045 | DOI:10.1371/journal.pone.0259574

PLoS Negl Trop Dis. 2021 Nov 10;15(11):e0009890. doi: 10.1371/journal.pntd.0009890. eCollection 2021 Nov.

ABSTRACT

INTRODUCTION: Soil transmitted helminth (STH) infections cause one of the most prevalent diseases in man. STHs disproportionately impact socio-economically disadvantaged communities including minority indigenous populations. This systematic review aimed to quantify the prevalence of STH infection within minority indigenous populations of the South-East Asia and Western Pacific Regions.

METHODS: The systematic review was conducted in accordance with The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines following a published protocol. A random effects meta-analysis was used to estimate the pooled prevalence of STH infection, and meta-regression analysis was used to quantify associations with study characteristics. Where comparative data were available, sub-group analysis was conducted to evaluate the risk of STH infection in minority indigenous people relative to other population groups. The heterogeneity between studies was evaluated visually using Forest plots and was assessed quantitatively by the index of heterogeneity (I2) and Cochran Q-statistics.

RESULTS: From 1,366 unique studies that were identified, 81 were included in the final analysis. The pooled prevalence of infection within minority indigenous populations was 61.4% (95% CI 50.8, 71.4) for overall STH infection; 32.3% (95% CI 25.7, 39.3) for Ascaris.lumbricoides; 43.6% (95% CI 32.6, 54.8) for Trichuris.trichiura; 19.9% (95% CI 15.7, 24.5) for hookworm and 6.3% (95% CI 3.2, 10.2) for Strongyloides.stercoralis. A significant increase in T. trichiura prevalence was observed over time. The stratified analysis showed that the prevalence of infection for STH overall and for each STH species were not significantly different in minority indigenous participants compared to other populations groups.

CONCLUSION: The prevalence of STH infection is high within minority indigenous populations across countries at very different levels of socio-economic development. The increasing prevalence of T. trichiura calls for the implementation of more effective therapies and control strategies.

PMID:34758024 | DOI:10.1371/journal.pntd.0009890

PLoS Negl Trop Dis. 2021 Nov 10;15(11):e0009924. doi: 10.1371/journal.pntd.0009924. eCollection 2021 Nov.

ABSTRACT

The World Health Organization (WHO) endorsed diagnosis of leprosy (also known as Hansen’s disease) entirely based on clinical cardinal signs, without microbiological confirmation, which may lead to late or misdiagnosis. The use of slit skin smears is variable, but lacks sensitivity. In 2017-2018 during the ComLep study, on the island of Anjouan (Union of the Comoros; High priority country according to WHO, 310 patients were diagnosed with leprosy (paucibacillary = 159; multibacillary = 151), of whom 263 were sampled for a skin biopsy and fingerstick blood, and 260 for a minimally-invasive nasal swab. In 74.5% of all skin biopsies and in 15.4% of all nasal swabs, M. leprae DNA was detected. In 63.1% of fingerstick blood samples, M. leprae specific antibodies were detected with the quantitative αPGL-I test. Results show a strong correlation of αPGL-I IgM levels in fingerstick blood and RLEP-qPCR positivity of nasal swabs, with the M. leprae bacterial load measured by RLEP-qPCR of skin biopsies. Patients with a high bacterial load (≥50,000 bacilli in a skin biopsy) can be identified with combination of counting lesions and the αPGL-I test. To our knowledge, this is the first study that compared αPGL-I IgM levels in fingerstick blood with the bacterial load determined by RLEP-qPCR in skin biopsies of leprosy patients. The demonstrated potential of minimally invasive sampling such as fingerstick blood samples to identify high bacterial load persons likely to be accountable for the ongoing transmission, merits further evaluation in follow-up studies.

PMID:34758041 | DOI:10.1371/journal.pntd.0009924

J Acquir Immune Defic Syndr. 2021 Dec 15;88(5):448-456. doi: 10.1097/QAI.0000000000002811.

ABSTRACT

INTRODUCTION: Recent studies project thousands of additional AIDS-related deaths because of COVID-19-related disruptions in HIV care. However, the extent to which disruptions in care have materialized since the start of the pandemic is not well understood.

METHODS: We use electronic health records to investigate how the pandemic has affected clinic visits, patients’ antiretroviral therapy (ART) supply, and viral suppression for a cohort of 14,632 HIV clients from a large HIV clinic in Kampala, Uganda. We complement this with an analysis of electronically measured longitudinal ART adherence data from a subcohort of 324 clients.

RESULTS: Clinic visits decreased by more than 50% after a national lockdown started. The risk of patients running out of ART on a given day increased from 5% before the lockdown to 25% 3 months later (Relative Risk Ratio of 5.11, 95% confidence interval: 4.99 to 5.24) and remained higher than prelockdown 6 months later at 13% (Relative Risk Ratio of 2.60; 95% confidence interval: 2.52 to 2.70). There was no statistically significant change in electronically measured adherence or viral suppression.

CONCLUSION: We document substantial gaps in HIV care after the start of the COVID-19 pandemic in Uganda. This suggests that measures to improve access should be explored as the pandemic persists. However, ART adherence was unaffected for the subcohort for whom we measured electronic adherence. This suggests that some clients may have stockpiles of ART tablets from previous prescriptions that allowed them to keep taking their medication even when they could not visit the clinic for ART refills.

PMID:34757973 | DOI:10.1097/QAI.0000000000002811

J Neural Eng. 2021 Nov 10. doi: 10.1088/1741-2552/ac387f. Online ahead of print.

ABSTRACT

OBJECTIVE: The efficacy of an adopted feature extraction method directly affects the classification of the electromyographic (EMG) signals in myoelectric control applications. Most methods attempt to extract the dynamics of the multi-channel EMG signals in the time domain and on a channel-by-channel, or at best pairs of channels, basis. However, considering multi-channel information to build a similarity matrix has not been taken into account.

APPROACH: Combining methods of long and short-term memory (LSTM) and dynamic temporal warping (DTW), we developed a new feature, called spatio-temporal warping (STW), for myoelectric signals. This method captures the spatio-temporal relationships of multi channels EMG signals.

MAIN RESULTS: Across four online databases, we show that in terms of average classification error and standard deviation values, the STW feature outperforms traditional features by 5% to 17%. In comparison to the more recent deep learning models, e.g. convolutional neural networks (CNN), STW outperformed by 5% to 18%. Also, STW showed enhanced performance when compared to the CNN+LSTM model by 2% to 14%. All differences were statistically significant with a large effect size.

SIGNIFICANCE: This feasibility study provides evidence supporting the hypothesis that spatio-temporal warping of the EMG signals can enhance the classification accuracy in an explainable way when compared to recent deep learning methods. Future work includes real-time implementation of the method and testing for prosthesis control.

PMID:34757954 | DOI:10.1088/1741-2552/ac387f

Phys Med Biol. 2021 Nov 10. doi: 10.1088/1361-6560/ac383f. Online ahead of print.

ABSTRACT

Breathing interplay effects in Intensity Modulated Proton Therapy (IMPT) arise from the interaction between target motion and the scanning beam. Assessing the detrimental effect of interplay and the clinical robustness of several mitigation techniques requires statistical evaluation procedures that take into account the variability of breathing during dose delivery. In this study, we present such a statistical method to model intra-fraction respiratory motion based on breathing signals and assess clinical relevant aspects related to the practical evaluation of interplay in IMPT such as how to model irregular breathing, how small breathing changes affect the final dose distribution, and what is the statistical power (number of different scenarios) required for trustworthy quantification of interplay effects. First, two data-driven methodologies to generate artificial patient-specific breathing signals are compared: a simple sinusoidal model, and a precise probabilistic deep learning model generating very realistic samples of patient breathing. Second, we investigate the highly fluctuating relationship between interplay doses and breathing parameters, showing that small changes in breathing period result in large local variations in the dose. Our results indicate that using a limited number of samples to calculate interplay statistics introduces a bigger error than using simple sinusoidal models based on patient parameters or disregarding breathing hysteresis during the evaluation. We illustrate the power of the presented statistical method by analyzing interplay robustness of 4DCT and Internal Target Volume (ITV) treatment plans for a 8 lung cancer patients, showing that, unlike 4DCT plans, even 33 fraction ITV plans systematically fail to fulfill robustness requirements.

PMID:34757958 | DOI:10.1088/1361-6560/ac383f

J Am Vet Med Assoc. 2021 Dec 15:1-5. doi: 10.2460/javma.20.05.0291. Online ahead of print.

ABSTRACT

OBJECTIVE: To characterize features of myxomatous mitral valve disease (MMVD) in Miniature Schnauzers and Yorkshire Terriers.

ANIMALS: 69 Miniature Schnauzers and 65 Yorkshire Terriers, each with MMVD.

PROCEDURES: Medical record data for each dog were collected; the study period was January 2007 through December 2016. If available, radiographic data were evaluated, and a vertebral heart scale score was assigned for each dog. Statistical analysis was performed with Student t and Fisher exact tests.

RESULTS: Compared with Yorkshire Terriers, the prevalence of MMVD was significantly higher in Miniature Schnauzers and affected dogs were significantly younger at the time of diagnosis. Miniature Schnauzers were significantly more likely to have mitral valve prolapse and syncope, compared with Yorkshire Terriers. Yorkshire Terriers were significantly more likely to have coughing and have had previous or current treatment with cardiac medications, compared with Miniature Schnauzers. There was no statistical difference between breeds with regard to abnormally high vertebral heart scale scores or radiographic evidence of congestive heart failure.

CONCLUSIONS AND CLINICAL RELEVANCE: With regard to MMVD, features of the disease among Miniature Schnauzers and Yorkshire Terriers were similar, but there were also a few discernable differences between these 2 breeds and from historical findings for dogs with MMVD of other breeds. Clinical signs at the time of diagnosis differed between the 2 breeds, which may have reflected concurrent breed-specific conditions (sick sinus syndrome or airway disease [eg, tracheal collapse]). Future work should include prospective studies to provide additional information regarding the natural progression of MMVD in these dog breeds.

PMID:34757932 | DOI:10.2460/javma.20.05.0291

J Am Vet Med Assoc. 2021 Dec 15:1-6. doi: 10.2460/javma.20.07.0420. Online ahead of print.

ABSTRACT

OBJECTIVE: To characterize the signalment, clinical signs, clinical pathological and histologic findings, and outcome in 8 related Bracchi Italiani with proteinuric kidney disease.

ANIMALS: 8 client-owned Bracchi Italiani.

PROCEDURES: Health records submitted to the Bracco Italiano Health Foundation and the Bracco Italiano Club of America between 2012 and 2019 were reviewed for dogs with evidence of nephropathy for which histologic diagnoses were obtained. Pedigree, signalment, clinical signs, diagnostic test results (including microscopic examination of kidney tissue samples collected ante- or postmortem), and outcome were acquired. Results were presented as descriptive statistics.

RESULTS: The most common clinical sign in affected dogs was inappetence. All dogs were proteinuric, and 4 dogs were azotemic. Seven dogs developed clinical signs of kidney disease and were euthanized a median of 75 days postdiagnosis. Six dogs had glomerular amyloidosis, and 1 dog each had nephrosclerosis and nonamyloidotic fibrillar glomerulopathy.

CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that the clinical presentation may vary in affected dogs, and proteinuria in young or middle-aged Bracchi Italiani should raise the concern for hereditary nephropathy. Prognosis is likely poor once clinical signs are noted.

PMID:34757934 | DOI:10.2460/javma.20.07.0420