Osteoarthritis, an old wine in a new bottle!

Osteoarthritis (OA) is the most common form of arthritis that has a major impact on patient morbidity and health care services. Despite its prevalence and impact, we do not have any effective management strategy to prevent or control their manifestations. Several decades of pharmacological development have failed to deliver a disease-modifying solution to OA. This editorial article outlines the lacunae in the research efforts of the past, the challenges that we are facing at present, and the exciting opportunities we have in the future for the management of OA. OA research has to be made more personalized concerning the phenotypic and endotypic disease variants. To begin with, robust disease classification criteria need to be defined for early OA, and biomarkers to detect such early diseases to aid in patient stratification. We also need to refine our clinical research design to make them more objective to meet the demands of the patient and the regulatory agencies. Embracing the current technologies such as artificial intelligence along with the use of genomic profiling from the omics platforms, the future of OA is more promising in developing appropriate management of OA.

[Influence of gender and place of residence differences on the evolution and mortality of ischemic cardiopathy in Catalonia: a population-based study.]

OBJECTIVE

Some bibliography supports a diagnostic and therapeutic delay in women with high cardiovascular risk. The objective of this paper was to know the incidence of cardiovascular disease (CVD) and mortality in a cohort with Metabolic Syndrome (MetS); analyze possible differences in gender and place of residence, regarding the performance of primary angioplasties in patients with ischemic heart disease (IHD).

METHODS

Population cohort study, with SIDIAP database (Sistema de Información para la Investigación en Atención Primaria), in primary care in Catalonia. We selected people of both sexes, between 35-75 years old, exempt from CVD at the beginning (2009), fulfilling MetS criteria (NCEP-ATPIII-National Cholesterol Education Program-Adult Treatment Panel III- criteria diagnoses). We performed descriptive statistics, and ANOVA and Chi-square test to evaluate differences between variables.

RESULTS

167,673 people met MetS criteria (5.2% of the population), 105,969 men (63.2%). 22% of the population belonged to rural areas. Those urban areas with the most socioeconomic differences (urban-1 and urban-5) exhibited the highest incidences of CVD and IHD. We registered 51,129 CVD (30.7%) of which 8,889 were acute myocardial infarctions (AMI) (5,3%) and 24,284 were IHD (14,5%). 1.758 primary angioplasties procedures were performed, 1,467 in men and 291 in women, representing, respectively, 4.4% and 0.9% (p<0.005).

CONCLUSIONS

The incidence of IHD and AMI in subjects with MetS is high in Catalonia. There is a difference in the angioplasties performed, according to sex and place of residence. Probably a practical implication would be to detect IHD in time in women with MetS, so that they can benefit from revascularization therapy in the same way as men.

Clinical Trial Design Innovations for Precision Medicine in Asthma

Severe asthma is a spectrum disorder with numerous subsets, many of which are defined by clinical history and a general predisposition for T2 inflammation. Most of the approved therapies for severe asthma have required clinical trial designs with population enrichment for exacerbation frequency and/or elevation of blood eosinophils. Moving beyond this framework will require trial designs that increase efficiency for studying nondominant subsets and continue to improve upon biomarker signatures. In addition to reviewing the current literature on biomarker-informed trials for severe asthma, this chapter will also review the advantages of master protocols and adaptive design methods for establishing the efficacy of new interventions in prospectively defined subsets of patients. The incorporation of methods that allow for data collection outside of traditional study visits at academic centers, called remote decentralized trial design, is a growing trend that may increase diversity in study participation and allow for enhanced resiliency during the COVID-19 pandemic. Finally, reaching the goals of precision medicine in asthma will require increased emphasis on effectiveness studies. Recent advances in real-world data utilization from electronic health records are also discussed with a view toward pragmatic trial designs that could also incorporate the evaluation of biomarker signatures.

A differential therapeutic consideration for use of corticosteroids according to established COVID-19 clinical phenotypes in critically ill patients

OBJECTIVE

To determine if the use of corticosteroids was associated with Intensive Care Unit (ICU) mortality among whole population and pre-specified clinical phenotypes.

DESIGN

A secondary analysis derived from multicenter, observational study.

SETTING

Critical Care Units.

PATIENTS

Adult critically ill patients with confirmed COVID-19 disease admitted to 63 ICUs in Spain.

INTERVENTIONS

Corticosteroids vs. no corticosteroids.

MAIN VARIABLES OF INTEREST

Three phenotypes were derived by non-supervised clustering analysis from whole population and classified as (A: severe, B: critical and C: life-threatening). We performed a multivariate analysis after propensity optimal full matching (PS) for whole population and weighted Cox regression (HR) and Fine-Gray analysis (sHR) to assess the impact of corticosteroids on ICU mortality according to the whole population and distinctive patient clinical phenotypes.

RESULTS

A total of 2017 patients were analyzed, 1171 (58%) with corticosteroids. After PS, corticosteroids were shown not to be associated with ICU mortality (OR: 1.0; 95% CI: 0.98-1.15). Corticosteroids were administered in 298/537 (55.5%) patients of "A" phenotype and their use was not associated with ICU mortality (HR=0.85 [0.55-1.33]). A total of 338/623 (54.2%) patients in "B" phenotype received corticosteroids. No effect of corticosteroids on ICU mortality was observed when HR was performed (0.72 [0.49-1.05]). Finally, 535/857 (62.4%) patients in "C" phenotype received corticosteroids. In this phenotype HR (0.75 [0.58-0.98]) and sHR (0.79 [0.63-0.98]) suggest a protective effect of corticosteroids on ICU mortality.

CONCLUSION

Our finding warns against the widespread use of corticosteroids in all critically ill patients with COVID-19 at moderate dose. Only patients with the highest inflammatory levels could benefit from steroid treatment.

Seasonal variation in antibiotic resistance genes and bacterial phenotypes in swine wastewater during three-chamber anaerobic pond treatment

Antibiotic resistance is a global public health concern. Antibiotic usage in pigs makes swine wastewater (SW) a reservoir for antibiotic resistance genes (ARGs). SW is usually stored and treated in a three-chamber anaerobic pond (3-CAP) in medium and small pig farms in northern China. However, the yet unexplored presence of ARGs in SW during 3-CAP treatment may result in ARGs spreading into the environment if farmers apply SW to farmland as a liquid organic fertilizer. This study investigated the profiles of and changes in ARGs in SW during its treatment in 3-CAP over four seasons and analyzed the correlation between ARGs and bacterial phenotypes, along with the physicochemical parameters of the water. The results revealed that ARG abundance decreased considerably after 3-CAP treatment in April (47%), October (47%), and December (62%) but increased in May (43%) and August (73%). The ARG copies in the influent and other SW samples increased significantly from 10⁷ copies/mL in April to 10⁹ copies/mL in October and were maintained in December. The increase in ARG abundance was not as rapid as the growth of the bacterial population, resulting in lower relative abundance in October and December. Bacterial communities possessed more sul1 and tetM genes, which were also positively correlated with mobile genetic elements. After the 3-CAP treatment, 16% of antibiotics and 60% of heavy metals were removed, and both had a weak correlation with ARGs. Predicted phenotypes showed that gram-positive (G⁺) and gram-negative (G^-) bacteria have different capacities for carrying ARGs. G⁺ bacteria carry more ARGs than G^- bacteria. This study revealed the persistence of ARGs in SW after 3-CAP treatment over different seasons. Applying SW in the proper month will mitigate ARG dissemination to the environment.

A differential therapeutic consideration for use of corticosteroids according to established COVID-19 clinical phenotypes in critically ill patients

Objective

To determine if the use of corticosteroids was associated with Intensive Care Unit (ICU) mortality among whole population and pre-specified clinical phenotypes.

Design

A secondary analysis derived from multicenter, observational study.

Setting

Critical Care Units.

Patients

Adult critically ill patients with confirmed COVID-19 disease admitted to 63 ICUs in Spain.

Interventions

Corticosteroids vs. no corticosteroids.

Main variables of interest

Three phenotypes were derived by non-supervised clustering analysis from whole population and classified as (A: severe, B: critical and C: life-threatening). We performed a multivariate analysis after propensity optimal full matching (PS) for whole population and weighted Cox regression (HR) and Fine-Gray analysis (sHR) to assess the impact of corticosteroids on ICU mortality according to the whole population and distinctive patient clinical phenotypes.

Results

A total of 2017 patients were analyzed, 1171 (58%) with corticosteroids. After PS, corticosteroids were shown not to be associated with ICU mortality (OR: 1.0; 95% CI: 0.98-1.15). Corticosteroids were administered in 298/537 (55.5%) patients of "A" phenotype and their use was not associated with ICU mortality (HR = 0.85 [0.55-1.33]). A total of 338/623 (54.2%) patients in "B" phenotype received corticosteroids. No effect of corticosteroids on ICU mortality was observed when HR was performed (0.72 [0.49-1.05]). Finally, 535/857 (62.4%) patients in "C" phenotype received corticosteroids. In this phenotype HR (0.75 [0.58-0.98]) and sHR (0.79 [0.63-0.98]) suggest a protective effect of corticosteroids on ICU mortality.

Conclusion

Our finding warns against the widespread use of corticosteroids in all critically ill patients with COVID-19 at moderate dose. Only patients with the highest inflammatory levels could benefit from steroid treatment.

Global Considerations in Asthma Treatment: Management in Low Resource Settings

Low-resource settings have a disproportionately higher burden of asthma due to factors that include environmental triggers, access to healthcare, availability of medications, and uncoordinated health systems. The application of guideline-based management can vary, which further impacts the treatment delivered. This chapter aims to outline the global landscape of asthma management, including cultural and social factors, with suggestions for interventions.

Sepsis biomarkers and diagnostic tools with a focus on machine learning

Over the last years, there have been advances in the use of data-driven techniques to improve the definition, early recognition, subtypes characterisation, prognostication and treatment personalisation of sepsis. Some of those involve the discovery or evaluation of biomarkers or digital signatures of sepsis or sepsis sub-phenotypes. It is hoped that their identification may improve timeliness and accuracy of diagnosis, suggest physiological pathways and therapeutic targets, inform targeted recruitment into clinical trials, and optimise clinical management. Given the complexities of the sepsis response, panels of biomarkers or models combining biomarkers and clinical data are necessary, as well as specific data analysis methods, which broadly fall under the scope of machine learning. This narrative review gives a brief overview of the main machine learning techniques (mainly in the realms of supervised and unsupervised methods) and published applications that have been used to create sepsis diagnostic tools and identify biomarkers.

The Italian severe/uncontrolled asthma registry (RItA): A 12-month clinical follow-up

BACKGROUND

follow-up studies on registries of severe/uncontrolled asthma (SUA) patients are scanty.

OBJECTIVE

to analyze baseline and follow-up characteristics of SUA patients and their longitudinal patterns.

METHODS

180 adult patients (age ≥15 yrs) were investigated at baseline and 12-month follow-up through the Italian SUA registry (RItA). Latent transition analysis (LTA) was performed to detect cross-sectional SUA phenotypes and longitudinal patterns. Risk factors for longitudinal patterns were assessed through logistic regression.

RESULTS

a significant/borderline improvement of asthma control outcomes in the last 2-4 weeks emerged at follow-up with respect to baseline for: daily activities limitations (Δ -16%), frequent diurnal symptoms (Δ -25%), uncontrolled asthma symptoms according to ACT (Δ -26%). Last 12-month use of oral corticosteroids was less frequent at follow-up than at baseline (Δ -25%). Health status improvement was confirmed by lung function test results. Through LTA, two longitudinal patterns were detected considering last 12-month control outcomes: "persistence/worsening" (53.9%), "under control/improvement" (46.1%). A lower likelihood of having "persistence/worsening" SUA was exhibited by patients under anti-IgE (OR 0.38, 95% CI 0.17-0.84) and inhaled corticosteroids-bronchodilator association treatment (OR 0.13, 95% CI 0.01-1.26, borderline value), while a higher likelihood was shown by older age at first asthma diagnosis (OR 1.04, 95% CI 1.01-1.07).

CONCLUSION

the implementation of a SUA registry, the availability of patient-level data and the application of an innovative longitudinal analysis allowed to observe a general improvement in asthma control, one year after baseline, and a lower risk of SUA "persistence/worsening" in patients under anti-IgE and regular ICS-bronchodilator association use.

Latent class analysis of imaging and clinical respiratory parameters from patients with COVID-19-related ARDS identifies recruitment subphenotypes

BACKGROUND

Patients with COVID-19-related acute respiratory distress syndrome (ARDS) require respiratory support with invasive mechanical ventilation and show varying responses to recruitment manoeuvres. In patients with ARDS not related to COVID-19, two pulmonary subphenotypes that differed in recruitability were identified using latent class analysis (LCA) of imaging and clinical respiratory parameters. We aimed to evaluate if similar subphenotypes are present in patients with COVID-19-related ARDS.

METHODS

This is the retrospective analysis of mechanically ventilated patients with COVID-19-related ARDS who underwent CT scans at positive end-expiratory pressure of 10 cmH₂O and after a recruitment manoeuvre at 20 cmH₂O. LCA was applied to quantitative CT-derived parameters, clinical respiratory parameters, blood gas analysis and routine laboratory values before recruitment to identify subphenotypes.

RESULTS

99 patients were included. Using 12 variables, a two-class LCA model was identified as best fitting. Subphenotype 2 (recruitable) was characterized by a lower PaO₂/FiO₂, lower normally aerated lung volume and lower compliance as opposed to a higher non-aerated lung mass and higher mechanical power when compared to subphenotype 1 (non-recruitable). Patients with subphenotype 2 had more decrease in non-aerated lung mass in response to a standardized recruitment manoeuvre (p = 0.024) and were mechanically ventilated longer until successful extubation (adjusted SHR 0.46, 95% CI 0.23-0.91, p = 0.026), while no difference in survival was found (p = 0.814).

CONCLUSIONS

A recruitable and non-recruitable subphenotype were identified in patients with COVID-19-related ARDS. These findings are in line with previous studies in non-COVID-19-related ARDS and suggest that a combination of imaging and clinical respiratory parameters could facilitate the identification of recruitable lungs before the manoeuvre.

Development and validation of novel sepsis subphenotypes using trajectories of vital signs

PURPOSE

Sepsis is a heterogeneous syndrome and identification of sub-phenotypes is essential. This study used trajectories of vital signs to develop and validate sub-phenotypes and investigated the interaction of sub-phenotypes with treatment using randomized controlled trial data.

METHODS

All patients with suspected infection admitted to four academic hospitals in Emory Healthcare between 2014-2017 (training cohort) and 2018-2019 (validation cohort) were included. Group-based trajectory modeling was applied to vital signs from the first 8 h of hospitalization to develop and validate vitals trajectory sub-phenotypes. The associations between sub-phenotypes and outcomes were evaluated in patients with sepsis. The interaction between sub-phenotype and treatment with balanced crystalloids versus saline was tested in a secondary analysis of SMART (Isotonic Solutions and Major Adverse Renal Events Trial).

RESULTS

There were 12,473 patients with suspected infection in training and 8256 patients in validation cohorts, and 4 vitals trajectory sub-phenotypes were found. Group A (N = 3483, 28%) were hyperthermic, tachycardic, tachypneic, and hypotensive. Group B (N = 1578, 13%) were hyperthermic, tachycardic, tachypneic (not as pronounced as Group A) and hypertensive. Groups C (N = 4044, 32%) and D (N = 3368, 27%) had lower temperatures, heart rates, and respiratory rates, with Group C normotensive and Group D hypotensive. In the 6,919 patients with sepsis, Groups A and B were younger while Groups C and D were older. Group A had the lowest prevalence of congestive heart failure, hypertension, diabetes mellitus, and chronic kidney disease, while Group B had the highest prevalence. Groups A and D had the highest vasopressor use (p < 0.001 for all analyses above). In logistic regression, 30-day mortality was significantly higher in Groups A and D (p < 0.001 and p = 0.03, respectively). In the SMART trial, sub-phenotype significantly modified treatment effect (p = 0.03). Group D had significantly lower odds of mortality with balanced crystalloids compared to saline (odds ratio (OR) 0.39, 95% confidence interval (CI) 0.23-0.67, p < 0.001).

CONCLUSION

Sepsis sub-phenotypes based on vital sign trajectory were consistent across cohorts, had distinct outcomes, and different responses to treatment with balanced crystalloids versus saline.

Data-driven clustering approach to identify novel phenotypes using multiple biomarkers in acute ischaemic stroke: A retrospective, multicentre cohort study

BACKGROUND

Acute ischaemic stroke (AIS) is a highly heterogeneous disorder and warrants further investigation to stratify patients with different outcomes and treatment responses. Using a large-scale stroke registry cohort, we applied data-driven approach to identify novel phenotypes based on multiple biomarkers.

METHODS

In a nationwide, prospective, 201-hospital registry study taking place in China between August 01, 2015 and March 31, 2018, the patients with AIS who were over 18 years of age and admitted to the hospital within 7 days from symptom onset were included. 92 biomarkers were included in the analysis. In the derivation cohort (n=9539), an unsupervised Gaussian mixture model was applied to categorize patients into distinct phenotypes. A classifier was developed using the most important biomarkers and was applied to categorize patients into their corresponding phenotypes in an validation cohort (n=2496). The differences in biological features, clinical outcomes, and treatment response were compared across the phenotypes.

FINDINGS

We identified four phenotypes with distinct characteristics in 9288 patients with non-cardioembolic ischaemic stroke. Phenotype 1 was associated with abnormal glucose and lipid metabolism. Phenotype 2 was characterized by inflammation and abnormal renal function. Phenotype 3 had the least laboratory abnormalities and small infarct lesions. Phenotype 4 was characterized by disturbance in homocysteine metabolism. Findings were replicated in the validation cohort. In comparison with phenotype 3, the risk of stroke recurrence (adjusted hazard ratio [aHR] 2.02, 95% confidence intervals [CI] 1.04-3.94), and mortality (aHR 18.14, 95%CI 6.62-49.71) at 3-month post-stroke were highest in phenotype 2, followed by phenotype 4 and phenotype 1, after adjustment for age, gender, smoking, drinking, history of stroke, hypertension, diabetes mellitus, dyslipidemia, and coronary heart disease. The Monte Carlo simulation showed that the patients with phenotype 2 could benefit from high-intensity statin therapy.

INTERPRETATION

A data-driven approach could aid in the identification of patients at a higher risk of adverse clinical outcomes following non-cardioembolic ischaemic stroke. These phenotypes, based on different pathophysiology, can suggest individualized treatment plans.

FUNDING

Beijing Natural Science Foundation (grant number Z200016), Beijing Municipal Committee of Science and Technology (grant number Z201100005620010), National Natural Science Foundation of China (grant number 82101360, 92046016, 82171270), Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (grant number 2019-I2M-5-029).

Understanding decision-making and educational need in the management of pediatric patients with moderate-to-severe asthma: analysis of a US-based clinician survey

BACKGROUND

Asthma creates a substantial burden on the pediatric healthcare system, particularly by those with moderate-to-severe disease. As few studies have been published specific to clinician evaluation and management of this population, this analysis serves to begin to identify educational needs and potential clinical impact.

METHODS

We conducted a case-based survey of US general pediatric (n = 227), allergy (n = 158), and pediatric pulmonology (n = 70) clinicians to understand the current approach to management of pediatric patients with moderate-to-severe asthma.

RESULTS

Results show inconsistencies in guideline adherence, identification of disease severity and control, referral practices, and knowledge of phenotypes, which may impact clinical decision making. While most clinicians refer to guidelines when managing pediatric patients with moderate-to-severe asthma, there is no preferred set, and they find the guidelines to be moderately useful. General pediatricians are more likely than specialists to have difficulty distinguishing control and severity and may not be familiar with the concept of asthma phenotype. Most surveyed pediatricians indicated they refer patients to a specialist, but did not always do so in the cases. Clinicians have little consensus on the best approach to manage patients with uncontrolled symptoms after optimized therapy. Many clinicians may have uncertainty about how elevated eosinophils or FeNO could affect patient management. Further, there may be gaps in incorporating parents and pediatric patients into shared decision-making in their care.

CONCLUSIONS

Understanding the needs of those managing patients with moderate-to-severe asthma is critical to developing effective continuing education activities to improve patient outcomes.

Implementation of individualised polygenic risk score analysis: a test case of a family of four

Background

Polygenic risk scores (PRS) have been widely applied in research studies, showing how population groups can be stratified into risk categories for many common conditions. As healthcare systems consider applying PRS to keep their populations healthy, little work has been carried out demonstrating their implementation at an individual level.

Case presentation

We performed a systematic curation of PRS sources from established data repositories, selecting 15 phenotypes, comprising an excess of 37 million SNPs related to cancer, cardiovascular, metabolic and autoimmune diseases. We tested selected phenotypes using whole genome sequencing data for a family of four related individuals. Individual risk scores were given percentile values based upon reference distributions among 1000 Genomes Iberians, Europeans, or all samples. Over 96 billion allele effects were calculated in order to obtain the PRS for each of the individuals analysed here.

Conclusions

Our results highlight the need for further standardisation in the way PRS are developed and shared, the importance of individual risk assessment rather than the assumption of inherited averages, and the challenges currently posed when translating PRS into risk metrics.

Defining the Phenotypes for Heart Failure With Preserved Ejection Fraction

PURPOSE OF REVIEW

Heart failure with preserved ejection fraction (HFpEF) imposes a significant burden on society and healthcare. The lack in efficacious therapies is likely due to the significant heterogeneity of HFpEF. In this review, we define various phenotypes based on underlying comorbidities or etiologies, discuss phenotypes arrived at by novel methods, and explore therapeutic targets.

RECENT FINDINGS

A few studies have used machine learning methods to uncover sub-phenotypes within HFpEF in an unbiased manner based on clinical features, echocardiographic findings, and biomarker levels. We synthesized the literature and propose three broad phenotypes: (1) young, with few comorbidities, usually obese and with low natriuretic peptide levels, (2) obese with substantive cardiometabolic burden and comorbidities and impaired ventricular relaxation, (3) old, multimorbid, with high rates of atrial fibrillation, renal and coronary artery disease, chronic obstructive pulmonary disease, and left ventricular hypertrophy. We also propose potential therapeutic strategies for these phenotypes.

The coronal alignment technique impacts deviation from native knee anatomy after total knee arthroplasty

PURPOSE

The aim of this study was to analyze and quantify the changes in native coronal alignment of a population of TKA patients according to different alignment goals.

METHODS

Five hundred and twenty TKAs were analyzed. The following angles were measured using an image-free navigation system prior to prosthetic implantation: medial femorotibial mechanical angle without stress and with maximum manual stress to reduce the deformity, medial distal femoral mechanical angle, medial proximal tibial mechanical angle. The native angles were derived from the osteoarthritic knee angles using a validated correction technique, and the overall, femoral and tibial coronal phenotypes were defined. Five different coronal alignment techniques were simulated: mechanical (MA), restricted mechanical (RMA), anatomical (AA), kinematic (KA) and restricted kinematic (RKA). The overall, femoral and tibial coronal phenotypes were compared before and after TKA. The primary endpoint was the binary criterion of whether or not TKA restored the natural overall phenotype. Secondary endpoints were the binary criteria of whether or not the natural femoral and tibial phenotypes were restored by TKA. The rates of restored and non restored phenotypes were compared with a Chi-square test at a 0.05 level of significance, with post hoc tests between all pairs of techniques at a 0.01 level of significance.

RESULTS

The overall phenotype was restored significantly differently by the five alignment techniques: 15% for MA, 23% for RMA, 2% for AA, 100% for KA and 79% for RKA (p < 0.001). There was a significant difference between each of the technique pairs (p < 0.01 to p < 0.001), except for the mechanical alignment-restricted mechanical alignment pair. The femoral phenotype was restored significantly differently by the five alignment techniques: 37% for MA, 58% for RMA, 19% for AA, 100% for KA and 85% for RKA (p < 0.001). The tibial phenotype was restored significantly differently by the five alignment techniques: 36% for MA, 36% for RMA, 17% for AA, 100% for KA and 88% for RKA (p < 0.001). There was a significant difference between each pair of techniques for both femoral and tibial phenotypes (p < 0.01 to p < 0.001).

CONCLUSION

Except for the kinematic alignment technique, the various alignment techniques induce significant changes in the pre-arthritic anatomy of the TKA patient. The surgeon must be aware of these modifications. The clinical relevance of this alteration still needs to be defined.

LEVEL OF EVIDENCE

III.

Valgus arthritic knees can be classified into nine phenotypes

PURPOSE

It is not shown whether anatomical variations exist in valgus arthritic limbs as to support individualized component and limb alignment. The null hypothesis was that there was no phenotypic variation of coronal femoro-tibial morphology in valgus knees. The aim was to determine whether distinct phenotypes of valgus knees could be identified to help surgical planning and classifying valgus knees for outcome studies.

METHODS

Full-leg weight-bearing radiographs of 233 knees (182 preoperative; 51 of contralateral arthritic knee) were measured for HKA (hip-knee-ankle angle), VCA (valgus correction angle), mLDFA (lateral mechanical distal femoral angle), aLDFA (lateral anatomical distal femoral angle), MPTA (medial proximal tibial angle), MNSA (medial neck shaft angle), TAMA (angle between tibial mechanical and anatomical axes), and TBA (tibial bowing angle).

RESULTS

Nine phenotypes were identified encompassing all 233 knees which could be clubbed into 4 broad types. Type 1 Neutral knees (12.5%) had almost normal values (mean VCA 5.3°, mLDFA 86.9°, aLDFA 81.1°). Type 2 'Intra-articular valgus' (22.7%) showed lateral compartment bone loss (mean mLDFA 83.9°; MPTA 90.2°). Type 3 'Extra-articular valgus' (35.2%) had extra-articular deformity: 3a showed valgus femoral bowing (mean VCA 2.7°); 3b valgus tibial bowing; 3c showed valgus tibial bowing with lateral femoral condyle wear (mean mLDFA 84.3°). Type 4 'Varus' type (29.6%) had features of varus knees: 4a had varus femoral bowing (VCA 8.3°); distal femur in 4b was akin to varus knees (mean mLDFA 89.3°) with lateral tibial bone loss (mean MPTA 91.2°). 4c had varus tibial bowing and deficient lateral femoral condyle (mLDFA 83.7°). 4d had varus tibial bowing and lateral tibial bone loss (mean MPTA 89.8°).

CONCLUSIONS

The study identified four broad groups of valgus arthritic knees with nine phenotypes based on coronal plane variations in femoro-tibial morphology. This study may be of value in planning and performing corrective osteotomies, and planning the optimal position of femoral and tibial components in unicompartmental and total knee arthroplasty. The classification presented in this study may aid in categorizing valgus knees for outcome studies.

LEVEL OF EVIDENCE

IV.

New insights into macrophage subsets in atherosclerosis

Macrophages in atherosclerotic patients are notably plastic and heterogeneous. Single-cell RNA sequencing (Sc RNA-seq) can provide information about all the RNAs in individual cells, and it is used to identify cell subpopulations in atherosclerosis (AS) and reveal the heterogeneity of these cells. Recently, some findings from Sc RNA-seq experiments have suggested the existence of multiple macrophage subsets in atherosclerotic plaque lesions, and these subsets exhibit significant differences in their gene expression levels and functions. These cells affect various aspects of plaque lesion development, stabilization, and regression, as well as plaque rupture. This article aims to review the content and results of current studies that used RNA-seq to explore the different types of macrophages in AS and the related molecular mechanisms as well as to identify the potential roles of these macrophage types in the pathogenesis of atherosclerotic plaques. Also, this review listed some new therapeutic targets for delaying atherosclerotic lesion progression and treatment based on the experimental results.

Seven phenotypes of varus osteoarthritic knees can be identified in the coronal plane

PURPOSE

Recommendations for resecting distal femur and proximal tibia in mechanical and anatomical alignment techniques are standardized. Kinematic alignment propagates individualizing resection planes. Whether significant variation exists, to warrant departure from standardized resection planes, has not been shown thus far in a large cohort of knees and with a wide range of varus deformity. The null hypothesis of this study was that there was no phenotypic variation in varus osteoarthritic knees. The aim of this paper was to determine whether distinct phenotypes could be identified, based on variations in coronal femoral and tibial morphology, which could aid in surgical planning and categorizing varus knees for future studies.

METHODS

2129 full-leg weightbearing radiographs were analyzed (1704 preoperative; 425 of contralateral arthritic knee). Measurements made were of HKA (hip-knee-ankle angle), VCA (valgus correction angle), mLDFA (lateral mechanical distal femoral angle), aLDFA (lateral anatomical distal femoral angle), MPTA (medial proximal tibial angle), MNSA (medial neck shaft angle), TAMA (angle between tibial mechanical and anatomical axes), and TPDR (percentage length of tibia proximal to extra-articular deformity).

RESULTS

Seven distinct types were identified covering 2021 knees, reducible to 4 broad phenotypes: 11% were Type 1 'Neutral' knees showing values close to reported normal knees (mean VCA 5.5°, mLDFA 87°, aLDFA 81°). 38% were Type 2 'Intra-articular varus' with medial intra-articular bone loss (mean mLDFA 90.9°, MPTA 85.4°, VCA of 5.7°). 41% were Type 3 'Extra-articular varus' with extra-articular deformity (EAD). Type 3a had proximal tibial EAD; Type 3b had tibial diaphyseal EAD; Type 3c had femoral EAD (mean VCA 8.7°, HKA 166°), and severe medial bone loss (mean mLDFA 92°, MPTA 83°). 9% were Type 4 'Valgoid type' with features of valgus knees: Type 4a had medial femoral bowing (mean VCA 2.9°); Type 4b had significant distal femoral valgus (mean mLDFA 85.3°, aLDFA 78.6°).

CONCLUSIONS

The null hypothesis that there was no phenotypic variation in varus osteoarthritic knees was rejected as considerable variation was found in coronal morphology of femur and tibia. Four broad phenotypic groups could be identified. Plane of the knee joint articular surface was quite variable. This has relevance to planning and performance of corrective osteotomies, unicompartmental and total knee arthroplasty.

LEVEL OF EVIDENCE

III, retrospective cohort study.

Occupational and environmental exposures in the Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis (GRADS) study

INTRODUCTION

Sarcoidosis is a granulomatous disorder thought to be caused by exposures in genetically susceptible individuals. This study investigated whether specific exposures were associated with different sarcoidosis phenotypes.

METHODS

Extensive demographic, occupational and environmental exposure data was analyzed from subjects enrolled in the NHLBI Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis (GRADS) study.

RESULTS

In patients with sarcoidosis, radiation exposure was significantly associated with an increased risk of cardiac sarcoidosis versus non-cardiac sarcoidosis. No exposures were significantly associated with pulmonary only disease versus extrapulmonary disease with or without pulmonary involvement, Scadding Stage II/III/IV versus Scadding Stage 0/I, acute or remitting disease versus non-acute or non-remitting disease, nor chronic versus non-chronic disease. Although not reaching statistically significance after adjustment for multiple comparisons, there were a number of exposures associated with specific disease phenotypes, including exposures where relationships to sarcoidosis have previously been described such as rural exposures and pesticide exposures.

CONCLUSIONS

Radiation exposure may be a risk factor for cardiac sarcoidosis. Other exposures may also be associated with specific phenotypes and should be further explored. The study was limited by small groups of exposed subjects for individual exposures and multiple comparisons. The development of novel and innovative exposure assessment tools is needed.

Functional knee phenotypes of OA patients undergoing total knee arthroplasty are significantly more varus or valgus than in a non-OA control group

PURPOSE

The aim of this study was to analyse the coronal alignment of a large population of patients undergoing total knee arthroplasty using a modern classification of the knee phenotypes found in a population of non-osteoarthritic individuals.

METHODS

Five hundred and four navigated total knee arthroplasties were included in the OA group. The following angles were measured with a computer image-free navigation system: mechanical femorotibial angle measured on the medial side without stress and with maximum manual stress to reduce deformation, and medial distal femoral mechanical angle. The native medial distal femoral and medial proximal tibial angles (coronal orientation of the femoral or tibial joint line after correction of wear) were calculated. The data were analysed as categorical data. These data were then compared with those published in a non-arthritic population, considered as a control non-OA group. The main criterion was the percentage of subjects with normal overall coronal alignment, defined by the association of a normal native medial distal femoral angle and a normal native medial proximal tibial angle. The secondary criteria were the percentages of subjects with normal medial femorotibial mechanical angle, normal native medial distal femoral angle and normal native medial proximal tibial angle. The influence of gender on primary and secondary criteria in the study group was analysed. The most frequent phenotypes in the study group were identified.

RESULTS

Normal overall coronal alignment was found in 66 patients in the OA group (12.7%) and 76 patients in the non-OA-group (24.7%) (p < 0.01 after adjustment by gender). There were fewer normal patients in the OA-group than in the non-OA-group for medial femorotibial mechanical angle, native medial distal femoral angle and native medial proximal tibial angle. In females, there were significantly fewer normal medial femorotibial mechanical angle. In males, there were significantly more cases with native medial distal femoral varus and in females more cases with native medial distal femoral valgus. There was no significant influence of gender on native medial proximal tibial angle. There was a wider distribution of the phenotypes in the OA-group than in the non-OA-group.

CONCLUSION

The distribution of functional phenotypes of the knee in patients undergoing total knee arthroplasty is different from those found in a reference non-osteoarthritic population.

LEVEL OF EVIDENCE

Level III-retrospective cohort study.

When Asthma and Chronic Obstructive Pulmonary Disease Overlap; Current Knowledge and Unmet Needs

Asthma and chronic obstructive pulmonary disease (COPD) are common diseases that often overlap. The term asthma-COPD overlap (ACO) has been used to define this entity but there remain several speculations on its exact definition, impact, pathophysiology, and clinical features. Patients with ACO have greater morbidity than those with asthma or COPD alone, but the information on the best therapeutic approach to this group of patients is still limited. Current treatment recommendations rely on expert opinions, roundtable discussions, and strategy documents. It is prudent to examine existing knowledge about ACO and determine the path for future research.

Characteristics of inflammatory bowel diseases in patients with concurrent immune-mediated inflammatory diseases

Patients with inflammatory bowel disease (IBD) are more likely to have concurrent immune-mediated inflammatory diseases (IMIDs) than those without IBD. IMIDs have been observed to alter the phenotype and outcomes of IBD in recent studies. Several studies have found that IBD patients with concurrent IMIDs may have more extensive or severe disease phenotypes, and are considered to be at increased risk of requiring biologics and IBD-related surgeries, suggesting that having multiple IMIDs is a poor prognostic factor for IBD. Furthermore, IBD patients with primary sclerosing cholangitis and Takayasu arteritis are reported to have unique endoscopic phenotypes, suggesting concurrent IMIDs can influence IBD phenotype with specific intestinal inflammatory distributions. In this review, we discuss the pathogenesis, disease phenotypes, and clinical outcomes in IBD patients with concomitant IMIDs.

Effects of light intensity, temperature, and salinity in allelopathic interactions between coexisting Synechococcus sp. phenotypes

Organisms from the Synechococcus genus constitute one of the major contributors to oceanic primary production, broadly distributed in waters with wide range of environmental conditions. This work investigated the influence of abiotic factors (temperature, irradiance, and salinity) on the strength of allelopathic interactions between different phenotypes of picoplanktonic cyanobacteria of the genus Synechococcus sp. (Type 1, Type 2, and Type 3a) employing mixed cultures and cell-free filtrate assays. The response variables studied were population growth and content of photosynthetic pigments: chlorophyll a (Chl a), carotenoids (Car), phycocyanin (PC), phycoerythrin (PE), and allophycocyanin (APC). Temperature was shown to be the most significant abiotic factor impacting the allelopathy of Synechococcus sp. phenotypes, with the Type 2 most significantly impacted. Irradiance also had a significant effect, having the largest effect on allelopathy of Type 3a phenotype. Changes in salinity had the greatest effect on allelopathy of Type 1. Our study has shown the significant influence of temperature, irradiance, and salinity on the strength of allelopathic compounds secreted by Synechococcus sp. phenotypes, with temperature the most significantly affecting allelopathic properties. Moreover, we discovered that the allelopathic response to changing environmental factors is highly phenotype-specific. This differential response of allelopathy could help different phenotypes of Synechococcus sp. to coexist in the water column.

Phenotype-Genotype Analysis Based on Molecular Classification in 135 Children With Mitochondrial Disease

OBJECTIVES

Over the past decades, mitochondrial disease classification has been mainly based on molecular defects. We aim to analyze phenotype-genotype correlation of mitochondrial disorders according to molecular classification.

METHODS

In this cohort study, we identified 135 individuals diagnosed with mitochondrial disorders, and all patients were divided into four subgroups based on molecular functions: the Respiratory Chain group (including subunits and assembly proteins in the respiratory chain), the Protein Synthesis group (including mitochondrial RNA metabolism, mitochondrial translation), the mitcohindrial DNA (mtDNA) Replication group, and the Others group (including cofactors, homeostasis, substrates, and inhibitors).

RESULTS

We found that in China, patients with the mtDNA variant constituted a large percentage of mitochondrial disease and were associated with a male preponderance in the Respiratory Chain group, whereas those in the Protein Synthesis group showed a relatively later onset and higher serum lactate level. In contrast, patients with nuclear DNA variants were younger at onset, with no specific lactate or cranial imaging features, especially in the Others group, which contained several mitochondrial diseases with corresponding treatment.

CONCLUSION

The mtDNA was recommended to detect first in patients with typical lactate and cranial imaging features. A broader consideration and detection are necessary for a better prognosis in an atypical patient.