Application of machine learning algorithms to predict osteoporosis in postmenopausal women with type 2 diabetes mellitus

PURPOSE

The screening and diagnosis of osteoporosis in patients with type 2 diabetes mellitus (T2DM) based on bone mineral density remains challenging because of the limited availability and accessibility of dual-energy X-ray absorptiometry. We aimed to develop and validate models to predict the risk of osteoporosis in postmenopausal women with T2DM based on machine learning (ML) algorithms.

METHODS

This retrospective study included 303 postmenopausal women with T2DM. To develop prediction models for osteoporosis, we applied nine ML algorithms combined with demographic, clinical, and laboratory data. The least absolute shrinkage and selection operator were used to perform feature selection. We used the bootstrap resampling technique for model training and validation. To test the performance of the models, we calculated indices including the area under the receiver operating characteristic curve (AUROC), accuracy, sensitivity, specificity, positive predictive value, negative predictive value, F1 score, calibration curve, and decision curve analysis. Furthermore, we conducted fivefold cross-validation for parameter optimization and model validation. Feature importance was assessed using the SHapley additive explanation (SHAP).

RESULTS

We identified 10 independent predictors as the most valuable features. An AUROC of 0.616-1.000 was observed for nine ML algorithms. The extreme gradient boosting (XGBoost) model exhibited the best performance, outperforming conventional risk assessment tools and registering 0.993 in the training set, 0.798 in the validation set, and 0.786 in the test set for fivefold cross-validation. Using SHAP, we found that the explanatory variables contributed to the model and their relationship with osteoporosis occurrence. Furthermore, we developed a user-friendly tool for calculating the risk of osteoporosis.

CONCLUSIONS

With the integration of demographic and clinical risk factors, ML algorithms can accurately predict osteoporosis. The XGBoost model showed ideal performance. With the incorporation of these models in the clinic, patients may benefit from early osteoporosis diagnosis and treatment.

BA.5 bivalent booster vaccination enhances neutralization of XBB.1.5, XBB.1.16 and XBB.1.9 variants in patients with lung cancer

This study reports that most patients with NSCLC had a significant increase in the nAb response to the currently circulating Omicron variants after bivalent booster vaccination and had Ab titers comparable to healthy participants. Interestingly, though the durability of the nAb response persisted in most of the healthy participants, patients with NSCLC had significantly reduced nAb titers after 4-6 months of vaccination. Our data highlight the importance of COVID-19 bivalent booster vaccination as the standard of care for patients with NSCLC given the evolution of new variants of concern.

Enhanced IgG immune response to COVID-19 vaccination in patients with sickle cell disease

Patients with sickle cell disease (SCD) are considered to be immunocompromised, yet data on the antibody response to SARS-CoV-2 vaccination in SCD is limited. We investigated anti-SARS-CoV-2 IgG titres and overall neutralizing activity in 201 adults with SCD and demographically matched non-SCD controls. Unexpectedly, patients with SCD generate a more robust and durable COVID-19 vaccine IgG response compared to matched controls, though the neutralizing activity remained similar across both cohorts. These findings suggest that patients with SCD achieve a similar antibody response following COVID-19 vaccination compared to the general population, with implications for optimal vaccination strategies for patients with SCD.

Antibody binding and neutralization of live SARS-CoV-2 variants including BA.4/5 following booster vaccination of patients with B-cell malignancies

Non-Hodgkin lymphoma and chronic lymphocytic leukemia (NHL/CLL) patients elicit inadequate antibody responses after initial SARS-CoV-2 vaccination and remain at high risk of severe COVID-19 disease. We investigated IgG, IgA, and IgM responses after booster vaccination against recent SARS-CoV-2 variants including Omicron BA.5 in 67 patients. Patients had lower fold increase and total anti-spike binding titers after booster than healthy individuals. Antibody responses negatively correlated with recent anti-CD20 therapy and low B cell numbers. Antibodies generated after booster demonstrated similar binding properties against SARS-CoV-2 variants compared to those generated by healthy controls with lower binding against Omicron variants. Importantly, 43% of patients showed anti-Omicron BA.1 neutralizing antibodies after booster and all these patients also had anti-Omicron BA.5 neutralizing antibodies. NHL/CLL patients demonstrated inferior antibody responses after booster vaccination, particularly against Omicron variants. Prioritization of prophylactic and treatment agents and vaccination of patients and close contacts with updated vaccine formulations are essential.

Antibody Response to COVID-19 mRNA Vaccine in Patients With Lung Cancer After Primary Immunization and Booster: Reactivity to the SARS-CoV-2 WT Virus and Omicron Variant

PURPOSE

To examine COVID-19 mRNA vaccine-induced binding and neutralizing antibody responses in patients with non-small-cell lung cancer (NSCLC) to SARS-CoV-2 614D (wild type [WT]) strain and variants of concern after the primary 2-dose and booster vaccination.

METHODS

Eighty-two patients with NSCLC and 53 healthy volunteers who received SARS-CoV-2 mRNA vaccines were included in the study. Blood was collected longitudinally, and SARS-CoV-2-specific binding and neutralizing antibody responses were evaluated by Meso Scale Discovery assay and live virus Focus Reduction Neutralization Assay, respectively.

RESULTS

A majority of patients with NSCLC generated binding and neutralizing antibody titers comparable with the healthy vaccinees after mRNA vaccination, but a subset of patients with NSCLC (25%) made poor responses, resulting in overall lower (six- to seven-fold) titers compared with the healthy cohort (P = < .0001). Although patients age > 70 years had lower immunoglobulin G titers (P = < .01), patients receiving programmed death-1 monotherapy, chemotherapy, or a combination of both did not have a significant impact on the antibody response. Neutralizing antibody titers to the B.1.617.2 (Delta), B.1.351 (Beta), and in particular, B.1.1.529 (Omicron) variants were significantly lower (P = < .0001) compared with the 614D (WT) strain. Booster vaccination led to a significant increase (P = .0001) in the binding and neutralizing antibody titers to the WT and Omicron variant. However, 2-4 months after the booster, we observed a five- to seven-fold decrease in neutralizing titers to WT and Omicron viruses.

CONCLUSION

A subset of patients with NSCLC responded poorly to the SARS-CoV-2 mRNA vaccination and had low neutralizing antibodies to the B.1.1.529 Omicron variant. Booster vaccination increased binding and neutralizing antibody titers to Omicron, but antibody titers declined after 3 months. These data highlight the concern for patients with cancer given the rapid spread of SARS-CoV-2 Omicron variant.

Humoral Responses Against SARS-CoV-2 and Variants of Concern After mRNA Vaccines in Patients With Non-Hodgkin Lymphoma and Chronic Lymphocytic Leukemia

PURPOSE

Patients with non-Hodgkin lymphoma including chronic lymphocytic leukemia (NHL/CLL) are at higher risk of severe SARS-CoV-2 infection. We investigated vaccine-induced antibody responses in patients with NHL/CLL against the original SARS-CoV-2 strain and variants of concern including B.1.167.2 (Delta) and B.1.1.529 (Omicron).

MATERIALS AND METHODS

Blood from 121 patients with NHL/CLL receiving two doses of vaccine were collected longitudinally. Antibody binding against the full-length spike protein, the receptor-binding, and N-terminal domains of the original strain and of variants was measured using a multiplex assay. Live-virus neutralization against Delta, Omicron, and the early WA1/2020 strains was measured using a focus reduction neutralization test. B cells were measured by flow cytometry. Correlation between vaccine response and clinical factors was determined.

RESULTS

Mean anti-SARS-CoV-2 spike immunoglobulin G-binding titers were 85-fold lower in patients with NHL/CLL compared with healthy controls, with seroconversion occurring in only 67% of patients. Neutralization titers were also lower and correlated with binding titers (P < .0001). Treatment with anti-CD20-directed therapies within 1 year resulted in 136-fold lower binding titers. Peripheral blood B-cell count also correlated with vaccine response. At 3 months from last anti-CD20-directed therapy, B-cell count ≥ 4.31/μL blood around the time of vaccination predicted response (OR 7.46, P = .04). Antibody responses also correlated with age. Importantly, neutralization titers against Delta and Omicron were reduced six- and 42-fold, respectively, with 67% of patients seropositive for WA1/2020 exhibiting seronegativity for Omicron.

CONCLUSION

Antibody binding and live-virus neutralization against SARS-CoV-2 and its variants of concern including Delta and Omicron were substantially lower in patients with NHL/CLL compared with healthy vaccinees. Anti-CD20-directed therapy < 1 year before vaccination and number of circulating B cells strongly predict vaccine response.

Herpes simplex virus lymphadenitis is associated with tumor reduction in a chronic lymphocytic leukemia patient

BACKGROUND

Herpes simplex virus lymphadenitis (HSVL) is an unusual presentation of HSV reactivation in chronic lymphocytic leukemia (CLL) patients characterized by systemic symptoms and no herpetic lesions. The immune responses during HSVL have not been studied.

METHODS

Peripheral blood and lymph node samples of a patient with HSVL were obtained. HSV-2 viral load, antibody levels, B and T cell responses, cytokine levels, and tumor burden were measured.

RESULTS

This patient showed HSV-2 viremia for at least 6 weeks. During this period, she had a robust HSV-specific antibody response with neutralizing and antibody-dependent cellular phagocytosis activity. Activated (HLA-DR+, CD38+) CD4+ and CD8+ T cells increased 18-fold and HSV-specific CD8+ T cells were detected in the blood at higher numbers. HSV-specific B and T cell responses in the lymph node were also detected. Markedly elevated levels of pro-inflammatory cytokines in the blood were also observed. Surprisingly, a sustained decrease in CLL tumor burden without CLL-directed therapy was observed with this and also a prior episode of HSVL.

CONCLUSION

HSVL should be considered as part of the differential diagnosis in CLL patients who present with signs and symptoms of aggressive lymphoma transformation. An interesting finding was the sustained tumor control after 2 episodes of HSVL in this patient. This tumor burden reduction may be due to the HSV-specific response serving as an adjuvant for activating tumor-specific or bystander T cells. Studies in additional CLL patients are needed to confirm and extend these findings.

FUNDING

National Institutes of Health and Winship Cancer Institute.

Determinants of Neutralizing Antibody Response After SARS CoV-2 Vaccination in Patients With Myeloma

PURPOSE

Vaccine-induced neutralizing antibodies (nAbs) play a critical role in protection from SARS CoV-2. Patients with B-cell malignancies including myeloma are at increased risk of COVID-19-related mortality and exhibit variable serologic response to the vaccine. The capacity of vaccine-induced antibodies in these patients to neutralize SARS CoV-2 or its variants is not known.

METHODS

Sera from 238 patients with multiple myeloma (MM) undergoing SARS CoV-2 vaccination were analyzed. Antibodies against the SARS CoV-2 spike receptor-binding domain (RBD) and viral nucleocapsid were measured to detect serologic response to vaccine and environmental exposure to the virus. The capacity of antibodies to neutralize virus was quantified using pseudovirus neutralization assay and live virus neutralization against the initial SARS CoV-2 strain and the B1.617.2 (Delta) variant.

RESULTS

Vaccine-induced nAbs are detectable at much lower rates (54%) than estimated in previous seroconversion studies in MM, which did not monitor viral neutralization. In 33% of patients, vaccine-induced antispike RBD antibodies lack detectable neutralizing capacity, including against the B1.617.2 variant. Induction of nAbs is affected by race, disease, and treatment-related factors. Patients receiving mRNA1273 vaccine (Moderna) achieved significantly greater induction of nAbs compared with those receiving BNT162b2 (Pfizer; 67% v 48%, P = .006).

CONCLUSION

These data show that vaccine-induced antibodies in several patients with MM lack detectable virus-neutralizing activity. Vaccine-mediated induction of nAbs is affected by race, disease, vaccine, and treatment characteristics. These data have several implications for the emerging application of booster vaccines in immunocompromised hosts.

Novel role of estrogen receptor-α on regulating chondrocyte phenotype and response to mechanical loading

OBJECTIVE

In knee cartilage from patients with osteoarthritis (OA), both preserved cartilage and damaged cartilage are observed. In this study, we aim to compare preserved with damaged cartilage to identify the molecule(s) that may be responsible for the mechanical loading-induced differences within cartilage degradation.

METHODS

Preserved and damaged cartilage were harvested from the same OA knee joint. RNA Sequencing was performed to examine the transcriptomic differences between preserved and damaged cartilage cells. Estrogen receptor-α (ERα) was identified, and its function of was tested through gene knockin and knockout. The role of ERα in mediating chondrocyte response to mechanical loading was examined via compression of chondrocyte-laded hydrogel in a strain-controlled manner. Findings from the studies on human samples were verified in animal models.

RESULTS

Level of estrogen receptor α (ERα) was significantly reduced in damaged cartilage compared to preserved cartilage, which were observed in both human and mice samples. Knockdown of ESR1, the gene encoding ERα, resulted in an upregulation of senescence- and OA-relevant markers in chondrocytes. Conversely, knockin of ESR1 partially reversed the osteoarthritic and senescent phenotype of OA chondrocytes. Using a three-dimensional (3D) culture model, we demonstrated that mechanical overload significantly suppressed ERα level in chondrocytes with concomitant upregulation of osteoarthritic phenotype. When ESR1 expression was suppressed, mechanical loading enhanced hypertrophic and osteogenic transition.

CONCLUSION

Our study demonstrates a new estrogen-independent role of ERα in mediating chondrocyte phenotype and its response to mechanical loading, and suggests that enhancing ERα level may represent a new method to treat osteoarthritis.

Antibody response to SARS-CoV-2 mRNA vaccine in lung cancer patients: Reactivity to vaccine antigen and variants of concern

PURPOSE

We investigated SARS-CoV-2 mRNA vaccine-induced binding and live-virus neutralizing antibody response in NSCLC patients to the SARS-CoV-2 wild type strain and the emerging Delta and Omicron variants.

METHODS

82 NSCLC patients and 53 healthy adult volunteers who received SARS-CoV-2 mRNA vaccines were included in the study. Blood was collected longitudinally, and SARS-CoV-2-specific binding and live-virus neutralization response to 614D (WT), B.1.617.2 (Delta), B.1.351 (Beta) and B.1.1.529 (Omicron) variants were evaluated by Meso Scale Discovery (MSD) assay and Focus Reduction Neutralization Assay (FRNT) respectively. We determined the longevity and persistence of vaccine-induced antibody response in NSCLC patients. The effect of vaccine-type, age, gender, race and cancer therapy on the antibody response was evaluated.

RESULTS

Binding antibody titer to the mRNA vaccines were lower in the NSCLC patients compared to the healthy volunteers (P=<0.0001). More importantly, NSCLC patients had reduced live-virus neutralizing activity compared to the healthy vaccinees (P=<0.0001). Spike and RBD-specific binding IgG titers peaked after a week following the second vaccine dose and declined after six months (P=<0.001). While patients >70 years had lower IgG titers (P=<0.01), patients receiving either PD-1 monotherapy, chemotherapy or a combination of both did not have a significant impact on the antibody response. Binding antibody titers to the Delta and Beta variants were lower compared to the WT strain (P=<0.0001). Importantly, we observed significantly lower FRNT50 titers to Delta (6-fold), and Omicron (79-fold) variants (P=<0.0001) in NSCLC patients.

CONCLUSIONS

Binding and live-virus neutralizing antibody titers to SARS-CoV-2 mRNA vaccines in NSCLC patients were lower than the healthy vaccinees, with significantly lower live-virus neutralization of B.1.617.2 (Delta), and more importantly, the B.1.1.529 (Omicron) variant compared to the wild-type strain. These data highlight the concern for cancer patients given the rapid spread of SARS-CoV-2 Omicron variant.

Current assessment of parental and health professional perception of the colour of neonatal vomiting: Results of a scoping survey

PURPOSE

To determine current perceptions of doctors, nurses and parents for the colour of a neonatal vomit which should prompt an urgent surgical review.

METHODS

A voluntary scoping survey of parents/guardians of patients and non-surgical healthcare professionals was conducted with respondents asked to choose from 8 different selections in a colour swatch from pale yellow to dark green. A control group consisted of 13 paediatric surgeons. Data were analysed using the paired t test, Fishers exact test. A p value of < 0.05 was considered to be significant.

RESULTS

365 participants responded: 36% (131/365) parents, 18% (64/365) nurses and 46% (166/365) doctors. 4/365 (1%) did not state their role. 343 participants completed all questions and responses were analysed using total responses for each question. 82% (121/148) of doctors and 78% (50/64) of nurses had more than 3 years of post-graduate experience. Overall, 63% (227/361) of participants (100% paediatric surgeons, 78% other doctors, 75% nurses/midwives & 30% parents) considered dark and light green vomits to be a sign of intestinal obstruction. 67% (242/361) of participants (100% paediatric surgeons, 72% other doctors, 56% nurses/midwives and 62% parents) believed dark and light green vomiting needed an urgent surgical referral. There were significant differences between the control group and other groups in terms of whether the neonate could wait until the next day for a review; nursing staff (p = 0.0002), postnatal/midwifery (p =  < 0.0001), emergency medicine (p = 0.04), general practice (p = 0.002), neonatal (p = 0.0001) and paediatricians (p = 0.005). Only the neonatologists (p = 0.04), nursing staff (p = 0.001) and postnatal/midwifery (p = 0.004) believed that the neonate could have safe observation.

CONCLUSION

Although the perception that green vomiting is potentially serious is acknowledged by the majority of healthcare professionals surveyed, there is still a requirement for more targeted educational practices in nursing, midwifery and medical staff.

Influenza Vaccination Rates Among Patients With a History of Cancer: Analysis of the National Health Interview Survey

Background

Annual influenza vaccination is recommended for all patients with cancer, but vaccine uptake data by cancer type and time since diagnosis are limited. We sought to estimate vaccination rates across different cancer types in the United States and determine whether rates vary over time since diagnosis.

Methods

Vaccination rates in individuals with solid tumor and hematological malignancies were estimated using data from 59 917 individuals obtained by the 2016 and 2017 National Health Interview Survey conducted by the Centers for Disease Control and Prevention.

Results

An average of 64% of the 5053 individuals with self-reported cancer received the influenza vaccine. Vaccination rates in men and women with solid tumors (66.6% and 60.3%, respectively) and hematological malignancies (58.1% and 59.2%, respectively) were significantly higher compared to those without cancer (38.9% and 46.8%, respectively). Lower rates were seen in uninsured patients, those younger than 45 years of age, and in African Americans with hematological malignancies but not with solid tumors. Vaccine uptake was similar regardless of time since cancer diagnosis.

Conclusions

Influenza vaccination rates are higher in men and women with cancer but remain suboptimal, highlighting the need for additional measures to improve vaccine compliance and prevent complications from influenza across all cancer types.

Discontinuation Patterns and Cost Avoidance of a Pharmacist-Driven Methicillin-Resistant Staphylococcus aureus Nasal Polymerase Chain Reaction Testing Protocol for De-escalation of Empiric Vancomycin for Suspected Pneumonia

A pharmacist-driven methicillin-resistant Staphylococcus aureus (MRSA) nasal polymerase chain reaction (PCR)-based testing protocol with a 70% acceptance rate for vancomycin discontinuation within 24 hours of negative results significantly reduced unnecessary vancomycin use with an estimated cost avoidance of $40 per vancomycin course. We found high concordance (141 of 147, 96%) of culture-based versus PCR-based MRSA nasal screening.

Gene expression profiling-based risk prediction and profiles of immune infiltration in diffuse large B-cell lymphoma

The clinical risk stratification of diffuse large B-cell lymphoma (DLBCL) relies on the International Prognostic Index (IPI) for the identification of high-risk disease. Recent studies suggest that the immune microenvironment plays a role in treatment response prediction and survival in DLBCL. This study developed a risk prediction model and evaluated the model’s biological implications in association with the estimated profiles of immune infiltration. Gene-expression profiling of 718 patients with DLBCL was done, for which RNA sequencing data and clinical covariates were obtained from Reddy et al. (2017). Using unsupervised and supervised machine learning methods to identify survival-associated gene signatures, a multivariable model of survival was constructed. Tumor-infiltrating immune cell compositions were enumerated using CIBERSORT deconvolution analysis. A four gene-signature-based score was developed that separated patients into high- and low-risk groups. The combination of the gene-expression-based score with the IPI improved the discrimination on the validation and complete sets. The gene signatures were successfully validated with the deconvolution output. Correlating the deconvolution findings with the gene signatures and risk score, CD8+ T-cells and naïve CD4+ T-cells were associated with favorable prognosis. By analyzing the gene-expression data with a systematic approach, a risk prediction model that outperforms the existing risk assessment methods was developed and validated.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

FRI0450 MEASURES OF DISEASE SEVERITY PREDICT DISABILITY AND QUALITY OF LIFE DIFFERENTLY IN RHEUMATOID ARTHRITIS AND CHRONIC CHIKUNGUNYA DISEASE

Background:

Chronic rheumatological manifestations similar to those of rheumatoid arthritis (RA) have been described after chikungunya virus infection. However, the clinical significance of the symptoms and disease severity in the two conditions has not been directly compared.

Objectives:

To compare, using identical measures of disease severity and patient outcomes, the impact of disease severity measures and symptoms on outcomes in RA and chronic chikungunya disease.

Methods:

Forty patients with chronic chikungunya arthralgia two years post-infection and 40 matched patients with RA were enrolled in Roraima, Brazil. Twenty-eight joints were assessed for tenderness and swelling, a pain intensity visual analogue scale, musculoskeletal stiffness questionnaire, modified Health Assessment Questionnaire and the EuroQol EQ5D-5L quality of life assessment were completed. The importance of the various measures of disease severity were analysed using Spearman’s rank correlation and regression analysis.

Results:

Tender and swollen joint counts, pain and stiffness were all predictive of the HAQ disability index in RA, but only stiffness was significantly associated with disability in chikungunya patients (Table 1). Tender and swollen joint counts, pain and stiffness were predictive for all EQ5D quality of life domains (except anxiety/depression) in RA patients. In contrast, in chikungunya disease, tender joint counts were predictive only of usual daily activities; pain was predictive of impaired mobility, self-care and discomfort, while stiffness was predictive for the mobility and anxiety/depression domains (Figure 1). Swollen joint counts were not associated with any of the patient outcomes in chikungunya disease. Linear regression analysis confirmed (p=0.003) that the effect of swollen joint count on the HAQ disability index depends on the underlying disease.

Table 1.

Association of disease severity with HAQ disability index in rheumatoid and CHIKV+ arthritis

Severity measureRheumatoid arthritisCHIKV+ arthritisr (p)r (p)Tender joint count0.56 (0.0002)0.24 (0.14)Swollen joint count0.60 (<0.0001)0.002 (0.99)Joint pain (VAS)0.55 (0.0002)0.29 (0.07)Stiffness severity0.57 (0.0001)0.38 (0.02)Figure 1.

Association of disease severity with quality of life domains in rheumatoid and CHIKV+ arthritis

Conclusion:

The value of all the disease severity measures tested in RA were confirmed, but tender joint counts may have more limited value in the assessment of chronic chikungunya disease. Joint swelling appears to have little impact for chikungunya patients, while stiffness appears to be an important metric to quantify chikungunya arthritis disease severity.

Disclosure of Interests:

Hugh Watson Shareholder of: Sanofi, Employee of: Sanofi, Ramão Luciano Nogueira-Hayd: None declared, Maony Rodrigues-Moreno: None declared, Felipe Naveca: None declared, Giulia Calusi: None declared, Richard Amdur: None declared, Karol Suchowiecki: None declared, Gary S. Firestein: None declared, Gary Simon: None declared, Aileen Chang: None declared

0303 Heart Rate and Systolic Blood Pressure Increase During Experimental Sleep Restriction

Introduction

Experimental sleep restriction is associated with elevated daytime cardiac activity, including heart rate (HR) and blood pressure (BP). However, some studies have found changes in systolic (SBP) but not diastolic blood pressure (DBP) or found changes in neither. Although findings are mixed, there may be a dose-response effect of cumulative sleep loss on daytime cardiac activity, such that HR and BP increase above basal levels with additional nights of insufficient sleep. This study examined changes in cardiac activity during experimental sleep restriction.

Methods

We used multilevel models with random effects for individuals to analyze data from 15 healthy males (M=22.3 years old, SD=2.8) in an 11-day inpatient protocol consisting of three nights of 10-hour/night baseline sleep opportunity, five nights of sleep restriction (5-hour/night sleep opportunity), and then two recovery nights (10-hour/night sleep opportunity). HR and BP were measured approximately every two hours during wake.

Results

HR increased 0.75 beats/minute with each successive night of sleep restriction (SE=0.18, p&lt;0.001). HR was 5.13 beats/minute higher during the recovery condition than during baseline or sleep restriction (SE=1.05, p&lt;0.001). During sleep restriction only, HR was lower in the later morning and evening compared to the earliest morning timepoint of the day, F(10, 743)=10.44, p&lt;0.001. SBP increased 0.33 mmHg following each successive night of sleep restriction (SE=0.16, p=0.041); however, SBP was only marginally higher during the sleep restriction condition than during baseline (b=1.90, SE=1.09, p=0.082).

Conclusion

Our findings suggest that HR and SBP increase with each additional day of experimental sleep restriction, even after accounting for diurnal effects on HR and SBP. HR did not recover to baseline levels following a night of recovery sleep, suggesting that longer recovery sleep may be necessary to recover from a week of sleep restriction.

Support

Grant UL1TR000127 (Chang PI), Clinical and Translational Science Institute; College of Health and Human Development at Pennsylvania State University.

0296 Less Self-Reported Alertness and Motivation During Sleep Restriction are Associated with Decreased Attentional Performance

Introduction

Some individuals demonstrate more performance decrements on the psychomotor vigilance task (PVT) after sleep restriction (SR). We investigated whether individuals who reported less alertness and/or less motivation after SR demonstrated poorer performance on the PVT.

Methods

Fifteen healthy men (22.3±2.8 years) participated in a 10-night inpatient protocol with three nights of 10-hour baseline time in bed (TIB), five nights of SR (5-hour TIB), then two recovery (10-hour TIB) nights. Participants completed the 10-minute PVT (Joggle Research® battery) approximately every two hours during wake. Outcomes included number of false starts (&lt;100 ms reaction time, RT) and number of lapses (≥500 ms RT). Participants reported alertness and motivation levels after each PVT. Median splits were used to characterize changes in alertness (“sleepy,” n=8, versus “alert,” n=7) and motivation (“unmotivated,” n=7, versus “motivated,” n=8) from the last day of baseline to the last day of SR. Outcomes were analyzed in mixed models with the predictor day*alertness or day*motivation, excluding the first three baseline days to preclude practice effects.

Results

There were significant interactions between day and alertness (p=.025) and day and motivation (p=.043) for false starts. False starts followed a quadratic inverted-U shape across days in sleepy (b=-0.16, p=.003) and unmotivated (b=-0.16, p=.004) participants, but not in alert or motivated participants (p&gt;.05). There was a significant interaction between day and alertness for lapses (p=.008); lapses followed a quadratic inverted-U shape across days with a stronger effect in sleepy (b=-0.43, p&lt;.001) versus alert (b=-0.15, p=.031) participants. There was no interaction between day and motivation for lapses.

Conclusion

Participants reporting less alertness were more likely to make both false starts and lapses after SR; those reporting less motivation were more likely to make false starts, but not lapses. Findings suggest greater motivation is sufficient to preserve inhibitory control but not vigilance after sleep restriction. In contrast, greater alertness despite sleep restriction was sufficient to preserve inhibitory control and resulted in lower vigilance decrements.

Support

This study was funded by grant UL1TR000127 from the Clinical and Translational Science Institute and the College of Health and Human Development at the Pennsylvania State University (Chang PI).

0085 Vulnerability to Sleep Restriction is Associated with Decreased Working Memory Performance

Introduction

We investigated whether individuals with more lapses on the psychomotor vigilance task (PVT) after sleep restriction (SR) demonstrated poorer working memory compared to those with fewer PVT lapses.

Methods

Fifteen healthy men (22.3±2.8 years) participated in a 10-night inpatient protocol with three nights of 10-hour baseline time in bed (TIB), five nights of SR (5-hour TIB), then two recovery (10-hour TIB) nights. Participants completed the Visual Object Learning Task (VOLT) and Fractal 2-Back (F2B; visual n-back) measuring working memory and the PVT (Joggle Research® battery) approximately every two hours during wake. During the VOLT, participants indicated whether presented images had been shown previously. Outcomes included number of misses and false alarms. During the F2B, participants tapped the screen when an image appeared that had been shown 2 images previously. Outcomes included sensitivity and specificity. Median split of mean PVT lapses after the last night of SR was used to categorize participants into “vulnerable” (n=8) versus “resistant” (n=7) groups. Outcomes were analyzed in mixed models with the predictor day*vulnerability, excluding the first three baseline days to preclude practice effects.

Results

There was a significant interaction between day and attentional vulnerability for VOLT misses (p&lt;.001); misses increased linearly across days in vulnerable (b=.18, p&lt;.001) but not resistant (p=.956) participants. There was no interaction between day and vulnerability for VOLT false alarms, which did not change across days. There was a significant interaction between day and attentional vulnerability for F2B sensitivity (p=.002); sensitivity increased linearly across days in resistant (b=.02, p&lt;.001) but not in vulnerable (p=.273) participants. There was no interaction between day and vulnerability for F2B specificity, which did not change across days.

Conclusion

Performance on the VOLT decreased in vulnerable participants only; performance on the F2B improved in resistant participants likely due to practice effects not seen in vulnerable participants. Findings indicate vulnerability to attentional lapses after SR is a marker of vulnerability to working memory decrements.

Support

This study was funded by grant UL1TR000127 from the Clinical and Translational Science Institute (Chang PI) and the College of Health and Human Development at the Pennsylvania State University.

Machine learning prediction of survival in diffuse large B-cell lymphoma based on gene-expression profiling

8047

Background: The current clinical risk stratification of Diffuse Large B-cell Lymphoma (DLBCL) relies on the International Prognostic Index (IPI) comprising a limited number of clinical variables but is imperfect in the identification of high-risk disease. Our study aimed to: (1) develop a risk prediction model based on the genetic and clinical features; and (2) evaluate the model’s biological implications in association with the estimated profiles of immune infiltration. Methods: Gene-expression profiling was performed on 718 patients with DLBCL for which RNA sequencing data and clinical covariates were available by Reddy et al (2017). Unsupervised and supervised machine learning methods were used to discover and identify the best set of survival-associated gene signatures for prediction. A multivariate model of survival from these signatures was constructed in the training set and validated in an independent test set. The compositions of the tumor-infiltrating immune cells were enumerated using CIBERSORT for deconvolution analysis. Results: A four gene-signature-based score was developed that separated patients into high- and low-risk groups with a significant difference in survival in the training, validation and complete cohorts (p < 0.001), independently of the IPI. The combination of the gene-expression-based score with the IPI improved the discrimination on the validation and complete sets. The area-under-the-curve at 2 and 5 years increased from 0.71 and 0.69 to 0.75 and 0.74 in the validation set, respectively. Conclusions: By analyzing the gene-expression data with a systematic approach, we developed and validated a risk prediction model that outperforms existing risk assessment methods. Our study, which integrated the profiles of immune infiltration with prognostic prediction, unraveled important associations that have the potential to identify patients who could benefit from the various therapeutic interventions, as well as highlighting possible targets for new drugs.

Remaining challenges in predicting patient outcomes for diffuse large B-cell lymphoma

Introduction: Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma and is an aggressive malignancy with heterogeneous outcomes. Diverse methods for DLBCL outcomes assessment ranging from clinical to genomic have been developed with variable predictive and prognostic success.Areas covered: The authors provide an overview of the various methods currently used to estimate prognosis in DLBCL patients. Models incorporating cell of origin, genomic features, sociodemographic factors, treatment effectiveness measures, and machine learning are described.Expert opinion: The clinical and genetic heterogeneity of DLBCL presents distinct challenges in predicting response to therapy and overall prognosis. Successful integration of predictive and prognostic tools in clinical trials and in a standard clinical workflow for DLBCL will likely require a combination of methods incorporating clinical, sociodemographic, and molecular factors with the aid of machine learning and high-dimensional data analysis.