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Nevin Manimala Statistics

Accuracy tradeoffs between individual bone and joint-level statistical shape models of knee morphology

Med Eng Phys. 2024 Aug;130:104203. doi: 10.1016/j.medengphy.2024.104203. Epub 2024 Jul 4.

ABSTRACT

Statistical shape models (SSMs) are useful tools in evaluating variation in bony anatomy to assess pathology, plan surgical interventions, and inform the design of orthopaedic implants and instrumentation. Recently, by considering multiple bones spanning a joint or the whole lower extremity, SSMs can support studies investigating articular conformity and joint mechanics. The objective of this study was to assess tradeoffs in accuracy between SSMs of the femur or tibia individually versus a combined joint-level model. Three statistical shape models were developed (femur-only, tibia-only, and joint-level) for a training set of 179 total knee arthroplasty (TKA) patients with osteoarthritis representing both genders and several ethnicities. Bone geometries were segmented from preoperative CT scans, meshed with triangular elements, and registered to a template for each SSM. Principal component analysis was performed to determine modes of variation. The statistical shape models were compared using measures of compactness, accuracy, generalization, and specificity. The generalization evaluation, assessing the ability to describe an unseen instance in a leave-one-out analysis, showed that errors were consistently smaller for the individual femur and tibia SSMs than for the joint-level model. However, when additional modes were included in the joint-level model, the errors were comparable to the individual bone results, with minimal additional computational expense. When developing more complex SSMs at the joint, lower limb, or whole-body level, the use of an error threshold to inform the number of included modes, instead of 95 % of the variation explained, can help to ensure accurate representations of anatomy.

PMID:39160028 | DOI:10.1016/j.medengphy.2024.104203

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Nevin Manimala Statistics

Combining robotics and functional electrical stimulation for assist-as-needed support of leg movements in stroke patients: A feasibility study

Med Eng Phys. 2024 Aug;130:104216. doi: 10.1016/j.medengphy.2024.104216. Epub 2024 Aug 3.

ABSTRACT

PURPOSE: Rehabilitation technology can be used to provide intensive training in the early phases after stroke. The current study aims to assess the feasibility of combining robotics and functional electrical stimulation (FES), with an assist-as-needed approach to support actively-initiated leg movements in (sub-)acute stroke patients.

METHOD: Nine subacute stroke patients performed repetitions of ankle dorsiflexion and/or knee extension movements, with and without assistance. The assist-as-needed algorithm determined the amount and type of support needed per repetition. The number of repetitions and range of motion with and without assistance were compared with descriptive statistics. Fatigue scores were obtained using the visual analogue scale (score 0-10).

RESULTS: Support was required in 44 % of the repetitions for ankle dorsiflexion and in 5 % of the repetitions of knee extension, The median fatigue score was 2.0 (IQR: 0.2) and 4.0 (IQR: 1.5) for knee and ankle, respectively, indicating mild to moderate perceived fatigue.

CONCLUSION: This study demonstrated the feasibility of assist-as-needed assistance through combined robotic and FES support of leg movements in stroke patients. It proved particularly useful for ankle dorsiflexion. Future research should focus on implementing this approach in a clinical setting, to assess clinical applicability and potential effects on leg function.

PMID:39160022 | DOI:10.1016/j.medengphy.2024.104216

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Nevin Manimala Statistics

Efficacy and safety of sequential therapy with subcutaneous belimumab and one cycle of rituximab in patients with systemic lupus erythematosus: the phase 3, randomised, placebo-controlled BLISS-BELIEVE study

Ann Rheum Dis. 2024 Aug 19:ard-2024-225686. doi: 10.1136/ard-2024-225686. Online ahead of print.

ABSTRACT

OBJECTIVES: Disease activity control in patients with systemic lupus erythematosus (SLE) with corticosteroid and immunosuppressant withdrawal is a treatment goal. We evaluated whether this could be attained with sequential subcutaneous belimumab (BEL) and one cycle of rituximab (RTX).

METHODS: In this phase 3, double-blind BLISS-BELIEVE trial (GSK Study 205646), patients with active SLE initiating subcutaneous BEL 200 mg/week for 52 weeks were randomised to intravenous placebo (BEL/PBO) or intravenous RTX 1000 mg (BEL/RTX) at weeks 4 and 6 while stopping concomitant immunosuppressants/tapering corticosteroids; standard therapy for 104 weeks (BEL/ST; reference arm) was included.

PRIMARY ENDPOINT: proportion of patients achieving disease control (SLE Disease Activity Index-2000 (SLEDAI-2K) ≤2; without immunosuppressants; prednisone equivalent ≤5 mg/day) at week 52 with BEL/RTX versus BEL/PBO. Major (alpha-controlled) secondary endpoints: proportion of patients with clinical remission (week 64; clinical SLEDAI-2K=0, without immunosuppressants/corticosteroids); proportion of patients with disease control (week 104). Other assessments: disease control duration, anti-dsDNA antibody, C3/C4 and B cells/B-cell subsets.

RESULTS: The modified intention-to-treat population included 263 patients. Overall, 16.7% (12/72) of BEL/PBO and 19.4% (28/144) of BEL/RTX patients achieved disease control (OR (95% CI) 1.27 (0.60 to 2.71); p=0.5342) at week 52. For major secondary endpoints, differences between BEL/RTX and BEL/PBO were not statistically significant. Anti-dsDNA antibodies and most assessed B cells/B-cell subsets were lower with BEL/RTX versus BEL/PBO. Mean disease control duration through 52 weeks was significantly greater with BEL/RTX versus BEL/PBO.

CONCLUSIONS: BEL/RTX showed no superiority over BEL/PBO for most endpoints analysed; however, it led to significant improvements in disease activity markers compared with BEL/PBO. Further investigation of combination treatment is warranted.

TRIAL REGISTRATION NUMBER: NCT03312907.

PMID:39159997 | DOI:10.1136/ard-2024-225686

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Nevin Manimala Statistics

Identifying impaired mental health in diabetes: a cross-sectional study in general practice

BJGP Open. 2024 Aug 19:BJGPO.2024.0045. doi: 10.3399/BJGPO.2024.0045. Online ahead of print.

ABSTRACT

BACKGROUND: Type two diabetes (T2D) is linked to impaired mental health. International guidelines emphasise the importance of including psychological aspects in diabetes care. Yet, no systematic approach has been implemented to assess mental health in patients with T2D in general practice.

AIM: To evaluate the mental health of patients with T2D in general practice, and to investigate the effectiveness of asking patients about their well-being by using a single-item question compared to the WHO five-item Well-being Index (WHO-5).

DESIGN & SETTING: Cross-sectional study, including 230 patients with T2D in Danish general practice from 1 May 2023 to 31 January 2024.

METHOD: Eligible patients were recruited at the annual chronic care consultation. They answered a single-item question on well-being and four validated measures of general well-being (WHO-5), depression (PHQ-9), anxiety (GAD-7), and diabetes distress (PAID-5).

RESULTS: Overall, 32% of patients expressed symptoms of impaired mental health. Notably, the WHO-5 identified 53% of these patients, whereas only 12% was identified through the single-item question. Importantly, among the patients exhibiting symptoms of impaired mental health, those identified by the WHO-5 displayed statistically significantly lower mental health scores across all measures (except PAID-5) compared to those not identified by the WHO-5.

CONCLUSION: A significant proportion of patients with T2D in general practice are affected by mental health issues. Our findings indicate that a single-item question may not sufficiently detect these issues, highlighting the importance of incorporating tools like the WHO-5 to offer a more comprehensive approach in diabetes care.

PMID:39159990 | DOI:10.3399/BJGPO.2024.0045

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Nevin Manimala Statistics

Development and Psychometric Analysis of the Physician and Nurse Brain Drain Attitude Scale

J Nurs Meas. 2024 Aug 19:JNM-2024-0041.R1. doi: 10.1891/JNM-2024-0041. Online ahead of print.

ABSTRACT

Background and Purpose: The Physician and Nurse Brain Drain Attitude Scale measures healthcare professionals’ attitudes toward brain drain, which affects healthcare systems in developing countries. Methods: The scale was developed using the methodologies proposed by Timothy R. Hinkin and Robert F. DeVellis, including qualitative research, expert evaluations, and exploratory and confirmatory factor analyses, with a sample of physicians and nurses from İzmir, Türkiye. Results: The scale comprises two factors: push and pull factors, demonstrating high reliability and confirmed validity through statistical tests indicating good fit and discriminant validity. Negative attitudes toward brain drain were linked to lower job satisfaction. Conclusions: This validated scale provides a crucial tool for understanding healthcare professionals’ perspectives on migration and its contributing factors.

PMID:39159963 | DOI:10.1891/JNM-2024-0041

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Nevin Manimala Statistics

Treatment Options for Signet Ring Cell Carcinoma of the Urinary Bladder: A Population-Based Study

Cancer Control. 2024 Jan-Dec;31:10732748241278485. doi: 10.1177/10732748241278485.

ABSTRACT

OBJECTIVES: Signet ring cell carcinoma (SRCC) of the urinary bladder is a rare and highly aggressive form of bladder cancer, with no widely agreed-upon treatment strategy. The aim of this study was to identify important factors influencing patient prognosis and to assess how various treatment approaches affect survival outcomes.

METHODS: A retrospective study was conducted using data from the Surveillance, Epidemiology, and End Results (SEER) Program, including patients with bladder primary SRCC who were presented between 2000 and 2017. Univariate and multivariate Cox regression models were used to examine the impact of various factors on cancer-specific survival (CSS) and overall survival (OS). Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were applied to homogenize both groups. The impact of different treatment regimens on patient CSS and OS was analyzed using the Kaplan-Meier method.

RESULTS: A total of 33 cases of non-muscular invasive SRCC and 210 cases of muscular invasive SRCC were included in this study. Multivariate analysis identified race, TNM stage, and surgical method as independent variables influencing both OS and CSS. In non-muscle invasive bladder SRCC patients, radical cystectomy showed no CSS benefit compared to transurethral resection of bladder tumors (P = 0.304). For muscle invasive SRCC, patients who underwent partial cystectomy had better OS and CSS compared to those who underwent radical cystectomy (P = 0.019, P = 0.024). However, after conducting a PSM analysis, the differences between the two surgical outcomes were not statistically significant (P = 0.504, P = 0.335). Lymphadenectomy, chemotherapy, and radiation did not show any benefit to the prognosis of patients.

CONCLUSION: This study identified race, TNM stage, and surgical approach as significant independent predictors for SRCC outcomes. Simple radical cystectomy and partial cystectomy proved to be effective treatments for SRCC. The optimal treatment option still needs to be supported by a number of prospective research trials.

PMID:39159955 | DOI:10.1177/10732748241278485

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Nevin Manimala Statistics

Association of Uterine Leiomyoma with Type 2 Diabetes Mellitus in Young Women: A Population-Based Cohort Study

Diabetes Metab J. 2024 Aug 19. doi: 10.4093/dmj.2023.0444. Online ahead of print.

ABSTRACT

BACKGROUND: We investigated the association between uterine leiomyoma (UL) and incident type 2 diabetes mellitus (T2DM) in young women.

METHODS: A nationwide population-based cohort study of 2,541,550 women aged between 20 and 40 years was performed using the National Health Information Database. Cox proportional hazards models were used to analyze the risk of incident T2DM according to the presence of UL and myomectomy.

RESULTS: The mean age was 29.70 years, and mean body mass index was 21.31 kg/m2. Among 2,541,550 participants, 18,375 (0.72%) women had UL. During a median 7.45 years of follow-up, 23,829 women (0.94%) were diagnosed with T2DM. The incidence of T2DM in women with UL (1.805/1,000 person-years) was higher than in those without UL (1.289/1,000 person-years). Compared with women without UL, women with UL had a higher risk of incident T2DM (hazard ratio, 1.216; 95% confidence interval [CI], 1.071 to 1.382). Women with UL who did not undergo myomectomy had a 1.505 times (95% CI, 1.297 to 1.748) higher risk for incident T2DM than women without UL. However, women with UL who underwent myomectomy did not have increased risk for incident T2DM.

CONCLUSION: Young women with UL were associated with a high risk of incident T2DM. In addition, myomectomy seemed to attenuate the risk for incident T2DM in young women with UL.

PMID:39159920 | DOI:10.4093/dmj.2023.0444

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Nevin Manimala Statistics

Insights of infected Schwann cells extinction and inherited randomness in a stochastic model of leprosy

Math Biosci. 2024 Aug 17:109281. doi: 10.1016/j.mbs.2024.109281. Online ahead of print.

ABSTRACT

Investigating disease progression, transmission of infection and impacts of Multidrug Therapy (MDT) to inhibit demyelination in leprosy involves a certain amount of difficulty in terms of the in-built uncertain complicated and complex intracellular cell dynamical interactions. To tackle this scenario and to elucidate a more realistic, rationalistic approach of examining the infection mechanism and associated drug therapeutic interventions, we propose a four-dimensional ordinary differential equation-based model. Stochastic processes has been employed on this deterministic system by formulating the Kolmogorov forward equation introducing a transition state and the quasi-stationary distribution, exact distribution analysis have been investigated which allow us to estimate an expected time to extinction of the infected Schwann cells into the human body more prominently. Additionally, to explore the impact of uncertainty in the key intracellular factors, the stochastic system is investigated incorporating random perturbations and environmental noises in the disease dissemination, proliferation and reinfection rates. Rigorous numerical simulations validating the analytical outcomes provide us significant novel insights on the progression of leprosy and unravelling the existing major treatment complexities. Analytical experiments along with the simulations utilizing Monte-Carlo method and Euler-Maruyama scheme involving stochasticity predicts that the bacterial density is underestimated due to the recurrence of infection and suggests that maintaining a drug-efficacy rate in the range 0.6-0.8 would be substantially efficacious in eradicating leprosy.

PMID:39159890 | DOI:10.1016/j.mbs.2024.109281

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Nevin Manimala Statistics

Circular code identified by the codon usage

Biosystems. 2024 Aug 17:105308. doi: 10.1016/j.biosystems.2024.105308. Online ahead of print.

ABSTRACT

Since 1996, circular codes in genes have been identified thanks to the development of 6 statistical approaches: trinucleotide frequencies per frame (Arquès and Michel, 1996), correlation functions per frame (Arquès and Michel, 1997), frame permuted trinucleotide frequencies (Frey and Michel, 2003, 2006), advanced statistical functions at the gene population level (Michel, 2015) and at the gene level (Michel, 2017). All these 3-frame statistical methods analyse the trinucleotide information in the 3 frames of genes: the reading frame and the 2 shifted frames. Notably, codon usage does not allow for the identification of circular codes (Michel, 2020). This has been a long-standing problem since 1996, hindering biologists’ access to circular code theory. By considering circular code conditions resulting from code theory, particularly the concept of permutation class, and building upon previous statistical work, a new statistical approach based solely on the codon usage, i.e. a 1-frame statistical method, surprisingly reveals the maximal C3 self-complementary trinucleotide circular code X in bacterial genes and in average (bacterial, archaeal, eukaryotic) genes, and almost in archaeal genes. Additionally, a new parameter definition indicates that bacterial and archaeal genes exhibit codon usage dispersion of the same order of magnitude, but significantly higher than that observed in eukaryotic genes. This statistical finding may explain the greater variability of codes in eukaryotic genes compared to bacterial and archaeal genes, an issue that has been open for many years. Finally, biologists can now search for new (variant) circular codes at both the genome level (across all genes in a given genome) and the gene level using only codon usage, without the need for analysing the shifted frames.

PMID:39159879 | DOI:10.1016/j.biosystems.2024.105308

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Nevin Manimala Statistics

Immersive and Nonimmersive Virtual Reality-Assisted Active Training in Chronic Musculoskeletal Pain: Systematic Review and Meta-Analysis

J Med Internet Res. 2024 Aug 19;26:e48787. doi: 10.2196/48787.

ABSTRACT

BACKGROUND: Virtual reality (VR) in different immersive conditions has been increasingly used as a nonpharmacological method for managing chronic musculoskeletal pain.

OBJECTIVE: We aimed to assess the effectiveness of VR-assisted active training versus conventional exercise or physiotherapy in chronic musculoskeletal pain and to analyze the effects of immersive versus nonimmersive VR on pain outcomes.

METHODS: This systematic review of randomized control trials (RCTs) searched PubMed, Scopus, and Web of Science databases from inception to June 9, 2024. RCTs comparing adults with chronic musculoskeletal pain receiving VR-assisted training were included. The primary outcome was pain intensity; secondary outcomes included functional disability and kinesiophobia. Available data were pooled in a meta-analysis. Studies were graded using the Cochrane Risk-of-Bias Tool version 2.

RESULTS: In total, 28 RCTs including 1114 participants with some concerns for a high risk of bias were identified, and 25 RCTs were included in the meta-analysis. In low back pain, short-term outcomes measured post intervention showed that nonimmersive VR is effective in reducing pain (standardized mean difference [SMD] -1.79, 95% CI -2.72 to -0.87; P<.001), improving disability (SMD -0.44, 95% CI -0.72 to -0.16; P=.002), and kinesiophobia (SMD -2.94, 95% CI -5.20 to -0.68; P=.01). Intermediate-term outcomes measured at 6 months also showed that nonimmersive VR is effective in reducing pain (SMD -8.15, 95% CI -15.29 to -1.01; P=.03), and kinesiophobia (SMD -4.28, 95% CI -8.12 to -0.44; P=.03) compared to conventional active training. For neck pain, immersive VR reduced pain intensity (SMD -0.55, 95% CI -1.02 to -0.08; P=.02) but not disability and kinesiophobia in the short term. No statistical significances were detected for knee pain or other pain regions at all time points. In addition, 2 (8%) studies had a high risk of bias.

CONCLUSIONS: Both nonimmersive and immersive VR-assisted active training is effective in reducing back and neck pain symptoms. Our study findings suggest that VR is effective in alleviating chronic musculoskeletal pain.

TRIAL REGISTRATION: PROSPERO CRD42022302912; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=302912.

PMID:39159449 | DOI:10.2196/48787