Time- and Race-Specific Haematological Reference Intervals for Healthy Volunteer Trials: A Retrospective Analysis of Pooled Data From Multiple Phase I Trials

White blood cell counts, ratios, and C-reactive protein among individuals with schizophrenia spectrum disorder and associations with long-term outcomes: a population-based study

BACKGROUND

Immune mechanisms are associated with adverse outcomes in schizophrenia; however, the predictive value of various peripheral immune biomarkers has not been collectively investigated in a large cohort before.

OBJECTIVE

To investigate how white blood cell (WBC) counts, ratios, and C-Reactive Protein (CRP) levels influence the long-term outcomes of individuals with schizophrenia spectrum disorder (SSD).

METHODS

We identified all adults in the Central Denmark Region during 1994-2013 with a measurement of WBC counts and/or CRP at first diagnosis of SSD. WBC ratios were calculated, and both WBC counts and ratios were quartile-categorized (Q4 upper quartile). We followed these individuals from first diagnosis until outcome of interest (death, treatment resistance and psychiatric readmissions), emigration or December 31, 2016, using Cox regression analysis to estimate adjusted hazard ratios (aHRs).

RESULTS

Among 6,845 participants, 375 (5.5 %) died, 477 (6.9 %) exhibited treatment resistance, and 1470 (21.5 %) were readmitted during follow-up. Elevated baseline levels of leukocytes, neutrophils, monocytes, LLR, NLR, MLR, and CRP increased the risk of death, whereas higher levels of lymphocytes, platelets, and PLR were associated with lower risk. ROC analysis identified CRP as the strongest predictor for mortality (AUC=0.84). Moreover, elevated levels of leukocytes, neutrophils, monocytes, LLR, NLR and MLR were associated with treatment resistance. Lastly, higher platelet counts decreased the risk of psychiatric readmissions, while elevated LLR increased this risk.

CONCLUSIONS

Elevated levels of WBC counts, ratios, and CRP at the initial diagnosis of SSD are associated with mortality, with CRP demonstrating the highest predictive value. Additionally, certain WBC counts and ratios are associated with treatment resistance and psychiatric readmissions.

Low energy availability increases immune cell formation of reactive oxygen species and impairs exercise performance in female endurance athletes

INTRODUCTION

The effects of low energy availability (LEA) on the immune system are poorly understood. This study examined the effects of 14 days of LEA on immune cell redox balance and inflammation at rest and in response to acute exercise, and exercise performance in female athletes.

METHODS

Twelve female endurance athletes (age: 26.8 ± 3.4 yrs, maximum oxygen uptake (V˙O2max): 55.2 ± 5.1 mL × min-1 × kg-1) were included in a randomized, single-blinded crossover study. They were allocated to begin with either 14 days of optimal energy availability diet (OEA, 52 ± 2 kcal × kg fat free mass (FFM)-1 × day-1) or LEA diet (22 ± 2 kcal × kg FFM-1 × day-1), followed by 3 days of refueling (OEA) with maintained training volume. Peripheral blood mononuclear cells (PBMCs) were isolated, and plasma obtained at rest before and after each dietary period. The PBMCs were used for analysis of mitochondrial respiration and H2O2 emission and specific proteins. Exercise performance was assessed on cycle by a 20-min time trial and time to exhaustion at an intensity corresponding to ∼110 % V˙O2max).

RESULTS

LEA was associated with a 94 % (P = 0.003) increase in PBMC NADPH oxidase 2 protein content, and a 22 % (P = 0.013) increase in systemic cortisol. LEA also caused an alteration of several inflammatory related proteins (P < 0.05). Acute exercise augmented H2O2 emission in PBMCs (P < 0.001) following both OEA and LEA, but to a greater extent following LEA. LEA also reduced the mobilization of white blood cells with acute exercise. After LEA, performance was reduced in both exercise tests (P < 0.001), and the reduced time trial performance remained after the 3 days of refueling (P < 0.001).

CONCLUSION

14 days of LEA in female athletes increased cortisol levels and had a pronounced effect on the immune system, including increased capacity for ROS production, altered plasma inflammatory proteome and lowered exercise induced mobilization of leukocytes. Furthermore, LEA resulted in a sustained impairment in exercise performance.

Racial differences in serological markers across the first year of injury in spinal cord injury: a retrospective analysis of a multi-center interventional study

STUDY DESIGN

Secondary analysis of a randomized, multi-center, placebo-controlled study(Sygen®).

OBJECTIVES

To evaluate racial differences in serological markers in individuals with spinal cord injury(SCI) across the first year of injury.

SETTING

Hospitals in North America.

METHODS

Serological markers (e.g.,cell count, liver, kidney, and pancreatic function, metabolism, and muscle damage) were assessed among 316 participants (247 White, 69 Black) at admission, weeks 1, 2, 4, 8, and 52 post-injury. Linear mixed models were employed to explore the main effects of time, race (Black vs. White), and their interaction, with adjustment of covariates such as study center, polytrauma, injury (level, completeness), treatment group, and sex.

RESULTS

A main effect of race was observed where White individuals had higher alanine transaminase, blood urea nitrogen(BUN), BUN/Creatinine ratio, sodium, and chloride, while Black individuals had higher calcium, total serum protein, and platelets. For markers with interaction effects, post-hoc comparisons showed that at week 52, White individuals had higher mature neutrophils, hematocrit, hemoglobin, mean corpuscular hemoglobin, albumin, and triglycerides, and Black individuals had higher amylase. Eosinophils, monocytes, red blood cells, aspartate aminotransferase, bilirubin, cholesterol, partial thromboplastin time, urine specific gravity, urine pH, CO2, and inorganic phosphorus did not differ between races.

CONCLUSIONS

Our results revealed racial differences in serological markers and underscores the importance of considering race as a determinant of physiological responses. Future studies are warranted to explore the causes and implications of these racial disparities to facilitate tailored clinical management and social policy changes that can improve health equity.

Hematologic and Oncologic Aspects of Sarcoidosis: Some of the Least Studied but Most Common Dilemmas

The hematologic system is frequently involved in sarcoidosis. Lymphopenia is the most common hematologic manifestation noted, although anemia and thrombocytopenia also occur. The etiology of these common manifestations can be direct granulomatous infiltration of bone marrow, lymph nodes, or spleen or related to immunologic dysfunction. Although not life threatening, these problems can lead to cytopenias requiring close monitoring in patients receiving a variety of disease treatments. The relationship between sarcoidosis and malignancy remains complex. However, some sarcoidosis patients are at increased risk for the development of malignancies, particularly lymphomas and gastrointestinal cancers. Conversely, cancer patients can experience an increase in the likelihood for the development of breast cancer and lymphomas.

Positive association between adiposity and inflammation in US adults: A cross-sectional study

Identification of biomarkers involved in multifaceted obesity-related inflammatory processes paired with reliable anthropometric measures of visceral adiposity is important for developing epidemiologic screening tools. This retrospective observational study used linear regression models to examine the association between inflammation and visceral fat in a nationally representative sample of 10 655 US adults. Inflammation was measured using a cumulative inflammation index (CII) generated from white blood cell ratios and uric acid. Intra-abdominal adiposity was assessed using sagittal abdominal diameter (SAD). Overall, 67.7%, 18.3%, and 13.9% of adults sampled were normoglycemic, prediabetic, and diabetic, with mean SAD of 21.7 ± 0.11 cm, 24.2 ± 0.14 cm, 26.0 ± 0.18 cm and CII of 4.3 ± 0.05, 4.7 ± 0.09, 5.1 ± 0.09, respectively. For each unit increase in SAD, CII was 0.12 higher (95% CI 0.10, 0.14) in US adults who were normoglycemic, 0.09 higher (95% CI 0.07, 0.12) in prediabetics and 0.10 higher (95% CI 0.07, 0.14) in diabetics. The association between SAD and CII was independent of diabetes status. These findings demonstrate an independent association between adiposity and inflammation, supporting increased visceral fat is associated with increased visceral-associated inflammation. Future studies are needed to define and characterise obesity-related inflammatory mediators and their role in chronic disease risk such as diabetes.

Difficult-to-treat asthma patients from ethnic minority groups in central England are at an enhanced risk of house dust mite sensitisation

BACKGROUND

House dust mite (HDM) is the most common sensitising allergen in asthma. Ethnic minority groups (EMGs) in the UK are more likely to live in deprived conditionings with a greater exposure to HDM and other aero-allergens.

AIM

To compare the ethnicity-based patterns of sensitisation to aero-allergens and the impact of ethnicity on clinical outcomes in patients with difficult-to-treat asthma (DTA).

METHODS

Data of patients with DTA were extracted from the registry of the Birmingham Regional Severe Asthma Service (BRSAS), which have a catchment population of 7.3million from Central England. Patients from White and EMG backgrounds were compared in terms of the prevalence of atopy, total serum immunoglobulin E (IgE), specific serum IgE (ssIgE) and asthma related clinical outcomes. Logistic regression analysis was conducted to explore ethnicity-based risk factors for HDM sensitisation.

RESULTS

A total of 1272 patients [White 1016 (79.9%), EMG 256 (20.1%) EMG] with a median age of 51 years (range 16-97) were included in the analysis. Patients from EMG were more likely (64%) to reside in the worst scale of index of multiple deprivation (IMD) than the White patients (25.5%), p < 0.0001. Positive HDM sensitisation was more prevalent in the EMG than in the White group [142/216 (66%) versus 375/842 (45%), p < 0.0001]. The median HDM ssIgE level was higher in the EMG than in the White group [3.0 KUA/L (IQR 0.06, 11.5) versus 0.1 (0.01, 3.0), p < 0.000001]. The odds ratio for positive sensitisation to HDM conveyed by the EMG status was 2.61 (95%CI, 1.8-3.8), p < 0.0001. Compared to the White group, the EMG had higher median total serum IgE [326 KU/L (115, 971) versus 114 (29.8, 434.8), p < 0.000001], higher blood eosinophil count (0.36 × 109 (0.18, 0.62) versus 0.23 (0.1,0.47), p < 0.000001), were marginally more atopic (79.2% vs. 75.6%, p = 0.098) and were less likely to being on maintenance oral corticosteroids (22% vs. 39.7%, p < 0.0001).

CONCLUSION

In this DTA cohort, positive HDM sensitisation was greater amongst the EMG than the White patients. The EMG status was a significant risk factor for HDM sensitisation.

Pre-Operative Neutrophil-to-Lymphocyte Ratio as a Predictor of Post-Operative Infectious Morbidity in Gynecologic Oncology Patients

Background: Neutrophil-to-lymphocyte ratio (NLR) has been described as a predictor of progression-free and overall survival, and in the field of peri-operative care it seems to be a factor that can help discriminate patients at risk of developing post-operative complications. In the present study we sought to determine whether NLR is useful as a biomarker in predictive models that aim to identify patients with gynecologic cancer undergoing surgery at risk of developing post-operative infectious morbidity. Patients and Methods: We designed a prospective cohort study that enrolled 208 patients with gynecologic cancer. Post-operative infectious morbidity was evaluated based on a 30-day follow-up interval from the procedure. Results: Forty-three patients (20.5%) developed post-operative infectious morbidity. Using an optimal cutoff value of 1.7 for the pre-operative NLR we observed that the sensitivity of the biomarker was 76.7% and the specificity 73.3% with a produced area under the curve of 0.760 (95% confidence interval [CI], 0.680-0.839). Univariable logistic regression indicated that NLR is a predictor of post-operative morbidity. Cox regression analysis revealed that NLR was the only factor that was associated with the timing of infectious morbidity (hazard ratio [HR], 1.339; 95% CI, 1.180-1.519; p < 0.001). Using random forest analysis and decision trees we achieved a diagnostic accuracy of the predictive model that exceeded 90%. Conclusions: Neutrophil-to-lymphocyte ratio may be a factor that could potentially help evaluate the risk of post-operative morbidity in patients with gynecologic cancer.

Assessment of immune cell profiles among post-menopausal women in the Women's Health Initiative using DNA methylation-based methods

BACKGROUND

Over the past decade, DNA methylation (DNAm)-based deconvolution methods that leverage cell-specific DNAm markers of immune cell types have been developed to provide accurate estimates of the proportions of leukocytes in peripheral blood. Immune cell phenotyping using DNAm markers, termed immunomethylomics or methylation cytometry, offers a solution for determining the body's immune cell landscape that does not require fresh blood and is scalable to large sample sizes. Despite significant advances in DNAm-based deconvolution, references at the population level are needed for clinical and research interpretation of these additional immune layers. Here we aim to provide some references for immune populations in a group of multi-ethnic post-menopausal American women.

RESULTS

We applied DNAm-based deconvolution to a large sample of post-menopausal women enrolled in the Women's Health Initiative (baseline, N = 58) or the ancillary Long Life Study (WHI-LLS, N = 1237) to determine the reference ranges of 58 immune parameters, including proportions and absolute counts for 19 leukocyte subsets and 20 derived cell ratios. Participants were 50-94 years old at the time of blood draw, and N = 898 (69.3%) self-identified as White. Using linear regression models, we observed significant associations between age at blood draw and absolute counts and proportions of naïve B, memory CD4+, naïve CD4+, naïve CD8+, memory CD8+ memory, neutrophils, and natural killer cells. We also assessed the same immune profiles in a subset of paired longitudinal samples collected 14-18 years apart across N = 52 participants. Our results demonstrate high inter-individual variability in rates of change of leukocyte subsets over this time. And, when conducting paired t tests to test the difference in counts and proportions between the baseline visit and LLS visit, there were significant changes in naïve B, memory CD4+, naïve CD4+, naïve CD8+, memory CD8+ cells and neutrophils, similar to the results seen when analyzing the association with age in the entire cohort.

CONCLUSIONS

Here, we show that derived cell counts largely reflect the immune profile associated with proportions and that these novel methods replicate the known immune profiles associated with age. Further, we demonstrate the value this methylation cytometry approach can add as a potential application in epidemiological studies.

Blood eosinophil count in the diagnosis of allergic-like rhinitis with chronic rhinosinusitis

BACKGROUND

Allergic rhinitis (AR) and nonallergic rhinitis (NAR) often are comorbid with chronic rhinosinusitis (CRS). Finding a convenient test that distinguishes these complex conditions is helpful for effective treatment. We aimed to analyse blood parameter differences between AR and NAR patients with/without CRS.

METHODS

Eight hundred thirteen patients, including AR and NAR with different conditions [CRS with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP)] were analysed in this retrospective study. Patients with a nasal deviation alone were included as healthy controls (HC). Receiver operating characteristic analysis was used to assess the value of blood parameters for diagnosing AR or NAR with/without CRS.

RESULTS

Compared to nonallergic-like rhinitis (HC, CRSwNP and CRSsNP), the blood eosinophil count was significantly increased in the allergic-like rhinitis groups, except for NAR-CRSsNP (AR, AR-CRSwNP, AR-CRSsNP, NAR and NAR-CRSwNP). The NAR-CRSsNP group had a higher level of eosinophils than the HC and CRSsNP groups. Among allergic-like rhinitis patients, eosinophils were higher in allergic-like rhinitis patients with CRSwNP (AR-CRSwNP and NAR-CRSwNP) than in allergic-like rhinitis patients without CRSwNP (AR, AR-CRSsNP, NAR and NAR-CRSsNP). However, no difference in blood eosinophils was observed between AR and NAR. There was also no difference among nonallergic-like rhinitis patients. Similar findings were found for the blood eosinophil proportion. Furthermore, the blood eosinophil count was a good predictor of allergic-like rhinitis, especially allergic-like rhinitis with CRSwNP.

CONCLUSION

The blood eosinophil count and proportion may be good diagnostic predictors of allergic-like rhinitis but cannot differentiate between AR and NAR. This indicator may be much better in predicting allergic-like rhinitis with CRSwNP.

Establishing pregnancy-specific haematological reference intervals in Ghana; a three-center cross-sectional study

BACKGROUND

Abnormal intra-pregnancy haematological variables are associated with adverse feto-maternal outcomes. However, the reference intervals (RIs) employed in sub-Saharan Africa to inform clinical decisions are generally imported. Since RIs are influenced by age, geographical location, and race, we hypothesized that context specific RIs should be established in Ghana to contextualize intra-pregnancy decision making.

METHODS

This cross-sectional study retrospectively retrieved data of 333 pregnant women with no known clinically determined intra-pregnancy complications; 22 participants in their first trimester (T1; 1-13 weeks), 177 in their T2 (14-27 weeks), and 132 in T3 (28-41 weeks). RIs for haematological parameters were non-parametrically determined at 2.5th and 97.5th percentiles in accordance with CLSI guidance document EP28-A3c. Two-sample comparisons were undertaken using Wilcoxon rank-sum tests whereas more than two-sample comparisons were undertaken using Kruskal-Wallis test. Statistical significance was set at p <0.05 under the two-tailed assumptions.

RESULTS

In accordance with WHO trimester-specific haemoglobin cutoffs, anaemia prevalence was a moderate (T1: 36.4%; 8/22 & T2: 31.6%; 56/177) to severe (T3:68.0%; 90/132) public health problem. Additionally, 9.3% (31/333) individuals had high gestational haemoglobin levels (Hb >13.0 g/dL). Moreover, haemoglobin (T2: 8.6-14.3 vs T3: 7.5-13.6 g/dL), MCH (T2: 22.5-69.8 vs T3: 21.6-31.9 pg), MCHC (T2: 30.2-51.8 g/L vs T3: 30.5-37.9 g/L), TWBC (T2: 4.0-13.4 vs T3: 4.1-13.0 x 109/L) required trimester specific RIs, compared to RBC (2.8-5.1 x 1012/L), MCV (66.2-100.2 fL), and platelet counts (106.3-388.3 x 109/L) that each required combined reference intervals.

CONCLUSIONS

The intra-pregnancy haematological RIs determined have appreciable lower limits; there is the need to determine context-specific thresholds for haematological variables predictive of positive and/or adverse maternal and infant health outcomes.

Association between peripheral blood cytopenia and cancer mortality: A race-specific risk factor for cancer death

BACKGROUND

Cytopenia is associated with cancer through mechanisms including clonal hematopoiesis and chronic inflammation. Cytopenia is more prevalent in Black people but its relationship with racial disparities in cancer mortality is unknown.

METHODS

Cytopenia was defined in 19,028 Black and White participants recruited between 2003 and 2007 for the REasons for Geographic and Racial Differences in Stroke cohort, based on age-, sex-, and race-adjusted ranges for blood counts. Cancer death was ascertained from Social Security Death and National Death Indexes. Multivariable Cox models estimated the risk of cancer mortality associated with cytopenia, adjusting for demographics (model1), anemia and cancer risk factors (model2), and socioeconomics (model3). Racial differences in the cytopenia-cancer death association were tested by cross-product interaction terms.

RESULTS

Cytopenia was identified in 383 (2%) participants, 250 (65%) White, and 113 (35%) Black people. With median follow-up 11.3 years, 1,224 (6.4%) cancer deaths occurred. Cytopenia was associated with increased risk of cancer mortality in model1 (HR = 1.57, 95%CI 1.15-2.24), model2 (HR = 1.67, 95%CI 1.22-2.30), and model3 (HR = 1.59, 95%CI 1.17-2.17). Participants with cytopenia had twofold increased cumulative incidence of cancer death (13% vs. 6.5%, p < 0.01). Race by cytopenia interaction terms showed higher HR for cancer death in Black compared to White participants: 2.01 versus 1.41 (p_interaction  = 0.016, model1), 2.12 versus 1.45 (p_interaction  = 0.009, model2), and 1.82 versus 1.44 (p_interaction  = 0.04, model3).

CONCLUSION

In this large, observational biracial prospective study, cytopenia was a risk factor for cancer death, with stronger association in Black than White people. Though race impacted the association of cytopenia with cancer mortality, cytopenia was not a mediator of the racial disparity in cancer mortality.

Personalized reference intervals: from theory to practice

Using laboratory test results for diagnosis and monitoring requires a reliable reference to which the results can be compared. Currently, most reference data is derived from the population, and patients in this context are considered members of a population group rather than individuals. However, such reference data has limitations when used as the reference for an individual. A patient's test results preferably should be compared with their own, individualized reference intervals (RI), i.e. a personalized RI (prRI).The prRI is based on the homeostatic model and can be calculated using an individual's previous test results obtained in a steady-state situation and estimates of analytical (CV_A) and biological variation (BV). BV used to calculate the prRI can be obtained from the population (within-subject biological variation, CV_I) or an individual's own data (within-person biological variation, CV_P). Statistically, the prediction interval provides a useful tool to calculate the interval (i.e. prRI) for future observation based on previous measurements. With the development of information technology, the data of millions of patients is stored and processed in medical laboratories, allowing the implementation of personalized laboratory medicine. PrRI for each individual should be made available as part of the laboratory information system and should be continually updated as new test results become available.In this review, we summarize the limitations of population-based RI for the diagnosis and monitoring of disease, provide an outline of the prRI concept and different approaches to its determination, including statistical considerations for deriving prRI, and discuss aspects which must be further investigated prior to implementation of prRI in clinical practice.

Diverse environmental perturbations reveal the evolution and context-dependency of genetic effects on gene expression levels

There is increasing appreciation that, in addition to being shaped by an individual's genotype and environment, most complex traits are also determined by poorly understood interactions between these two factors. So-called "genotype × environment" (G×E) interactions remain difficult to map at the organismal level but can be uncovered using molecular phenotypes. To do so at large scale, we used TM3'seq to profile transcriptomes across 12 cellular environments in 544 immortalized B cell lines from the 1000 Genomes Project. We mapped the genetic basis of gene expression levels across environments and revealed a context-dependent genetic architecture: The average heritability of gene expression levels increased in treatment relative to control conditions, and on average, each treatment revealed new expression quantitative trait loci (eQTLs) at 11% of genes. Across our experiments, 22% of all identified eQTLs were context-dependent, and this group was enriched for trait- and disease-associated loci. Further, evolutionary analyses suggested that positive selection has shaped G×E loci involved in responding to immune challenges and hormones but not to man-made chemicals. We hypothesize that this reflects a reduced opportunity for selection to act on responses to molecules recently introduced into human environments. Together, our work highlights the importance of considering an exposure's evolutionary history when studying and interpreting G×E interactions, and provides new insight into the evolutionary mechanisms that maintain G×E loci in human populations.

Normal B cell ranges in infants: A systematic review and meta-analysis

BACKGROUND

During the first year of life, B cell level is a valuable indicator of whether external factors, such as exposure to B cell depleting therapies, have an adverse impact on immune system development. However, there are no standard reference ranges of B cell levels in healthy infants by age.

OBJECTIVE

To estimate the normal range of B cell levels in infants, by age, during the first year of life, by pooling data from published studies.

METHODS

Studies reporting B cell levels measured using flow cytometry and CD19 markers in healthy infants were identified via a systematic literature review. Quality and feasibility assessments determined suitability for inclusion in meta-analyses by age group and/or continuous age. Means and normal ranges (2.5th-97.5th percentile) were estimated for absolute and percentage B cell levels. Sensitivity analyses assessed the impact of various assumptions.

RESULTS

Of 37 relevant studies identified, 28 were included in at least 1 meta-analysis. Means and normal ranges of B cell levels were found to be 707 (123-2324) cells/μL in cord blood, 508 (132-1369) cells/μL at age 0-1 month, 1493 (416-3877) cells/μL at age 1-6 months and 1474 (416-3805) cells/μL at age >6 months. The continuous age model showed that B cell levels peaked at week 26. Trends were similar for the percentage B cell estimates and in sensitivity analyses.

CONCLUSION

These meta-analyses provide the first normal reference ranges for B cell levels in infants, by week of age, during the first year of life.

Irradiation immunity interactions

The immune system can influence cancer development by both impeding and/or facilitating tumour growth and spread. A better understanding of this complex relationship is fundamental to optimise current and future cancer therapeutic strategies. Although typically regarded as a localised and immunosuppressive anti‐cancer treatment modality, radiation therapy has been associated with generating profound systemic effects beyond the intended target volume. These systemic effects are immune‐driven suggesting radiation therapy can enhance anti‐tumour immunosurveillance in some instances. In this review, we summarise how radiation therapy can positively and negatively affect local and systemic anti‐tumour immune responses, how co‐administration of immunotherapy with radiation therapy may help promote anti‐tumour immunity, and how the use of immune biomarkers may help steer radiation therapy‐immunotherapy personalisation to optimise clinical outcomes.

Benign ethnic neutropenia: an analysis of prevalence, timing and identification accuracy in two large inner-city NHS hospitals

BACKGROUND

Benign ethnic neutropenia (BEN) is the most common cause of chronic neutropenia seen in individuals of African, Middle Eastern and West Indian descent. This phenotype is broadly defined by an absolute neutrophil counts (ANC) below 1.8 × 10⁹ cells/L in the absence of other causes, without an increased risk of infection. BEN has been implicated as a potential source of disparity in patients treated with clozapine, the antipsychotic of choice in treatment-resistant schizophrenia. Our main objective was to examine the current level of BEN recognition in a cohort of patients treated with clozapine and the potential impact of unidentified BEN on the initiation and maintenance of clozapine treatment.

METHODS

This was an observational, retrospective analysis of patients registered with clozapine haematological monitoring systems in two large mental health trusts, chosen because they serve an ethnically diverse population. The first objective was to establish certified BEN prevalence in current users of clozapine. The second objective was to explore the stage of treatment at which BEN was identified. The third objective was to evaluate the extent of unrecognised BEN in patients registered on the Central Non-Rechallenge Database (CNRD), a database for patients whose haematological parameters fall below set thresholds when receiving clozapine treatment, meaning they cannot ordinarily be prescribed clozapine again.

RESULTS

The study population comprised of 2020 patients on the clozapine register. 111 patients were monitored under BEN criteria. BEN was mostly identified after a below threshold haematological result or clozapine rechallenge (68%) compared to at clozapine initiation (32%). Eight of the 18 (42%) black patients registered on the CNRD were classified as BEN after assessment by a haematologist. Of these 8 patients, none would have met CNRD criteria again if monitored with BEN criteria at clozapine initiation.

CONCLUSIONS

Current evidence suggests that BEN remains an uncommonly recognised haematological phenotype. Improved timely identification of BEN will reduce unnecessary interruption or discontinuation of clozapine treatment. Our results suggest consideration should also be given to determining BEN status prior to initiating clozapine. Moreover, adoption of current FDA BEN monitoring criteria in the UK may further reduce clozapine discontinuation due to perceived neutropenia as drug toxicity, particularly in treatment-refractory schizophrenia patients.

Persistence of Eosinophilic Asthma Endotype and Clinical Outcomes: A Real-World Observational Study

Purpose

Eosinophil count elevations are predictive of adverse outcomes in patients with asthma, yet little is known regarding longitudinal eosinophil patterns and their association with clinical outcomes. The goal of this study was to assess associations between longitudinal persistence of eosinophil elevations and both clinical outcomes and health care resource utilization (HCRU).

Methods

Data were extracted from 2 databases in the United Kingdom. Patients included were aged ≥13 years, had active asthma, and had ≥3 blood eosinophil count (BEC) recordings. Patients were categorized by BEC as: never high (all BEC ≤300 cells/µL), intermittently high (≥1 BEC >300 cells/µL but <75% of BEC >300 cells/µL), or persistently high (≥75% of BEC >300 cells/µL). Asthma exacerbations, asthma control (risk domain, overall, and full), and HCRU were evaluated for 12 months after the last BEC.

Results

The study population comprised 148,021 patients. Persistently high, intermittently high, and never high eosinophil patterns were detected in 13.6%, 40.5%, and 45.9% of patients, respectively. Patients with ≥1 elevated BEC were at greater risk for severe asthma exacerbations, regardless of whether the elevation was persistent (rate ratio [RR]: 1.28 [95% CI 1.24–1.33]; P < 0.001) or intermittent (RR: 1.24 [95% CI 1.21–1.27]; P < 0.001), compared with patients with no eosinophil elevations. Full asthma control was achieved by <25% of patients across eosinophil pattern groups, and HCRU did not appreciably differ, although patients with persistently high BEC had the shortest hospital stay duration among the groups.

Conclusion

These data suggest that elevated blood eosinophils, regardless of persistency, signify increased risk of severe asthma exacerbations.

Sex Differences in the Physiological Network of Healthy Young Subjects

Within human physiology, systemic interactions couple physiological variables to maintain homeostasis. These interactions change according to health status and are modified by factors such as age and sex. For several physiological processes, sex-based distinctions in normal physiology are present and defined in isolation. However, new methodologies are indispensable to analyze system-wide properties and interactions with the objective of exploring differences between sexes. Here we propose a new method to construct complex inferential networks from a normalization using the clinical criteria for health of physiological variables, and the correlations between anthropometric and blood tests biomarkers of 198 healthy young participants (117 women, 81 men, from 18 to 27 years old). Physiological networks of men have less correlations, displayed higher modularity, higher small-world index, but were more vulnerable to directed attacks, whereas networks of women were more resilient. The networks of both men and women displayed sex-specific connections that are consistent with the literature. Additionally, we carried out a time-series study on heart rate variability (HRV) using Physionet's Fantasia database. Autocorrelation of HRV, variance, and Poincare's plots, as a measure of variability, are statistically significant higher in young men and statistically significant different from young women. These differences are attenuated in older men and women, that have similar HRV distributions. The network approach revealed differences in the association of variables related to glucose homeostasis, nitrogen balance, kidney function, and fat depots. The clusters of physiological variables and their roles within the network remained similar regardless of sex. Both methodologies show a higher number of associations between variables in the physiological system of women, implying redundant mechanisms of control and simultaneously showing that these systems display less variability in time than those of men, constituting a more resilient system.

Risk of common infections in people with inflammatory bowel disease in primary care: a population-based cohort study

OBJECTIVE

To evaluate the risk of common infections in individuals with inflammatory bowel disease (IBD) [ulcerative colitis and Crohn's disease] compared with matched controls in a contemporary UK primary care population.

DESIGN

Matched cohort analysis (2014-2019) using the Royal College of General Practitioners Research and Surveillance Centre primary care database. Risk of common infections, viral infections and gastrointestinal infections (including a subset of culture-confirmed infections), and predictors of common infections, were evaluated using multivariable Cox proportional hazards models.

RESULTS

18 829 people with IBD were matched to 73 316 controls. People with IBD were more likely to present to primary care with a common infection over the study period (46% vs 37% of controls). Risks of common infections, viral infections and gastrointestinal infections (including stool culture-confirmed infections) were increased for people with ulcerative colitis and Crohn's disease compared with matched controls (HR range 1.12-1.83, all p<0.001). Treatment with oral glucocorticoid therapy, immunotherapies and biologic therapy, but not with aminosalicylates, was associated with increased infection risk in people with IBD. Despite mild lymphopenia and neutropenia being more common in people with IBD (18.4% and 1.9%, respectively) than in controls (6.5% and 1.5%, respectively), these factors were not associated with significantly increased infection risk in people with IBD.

CONCLUSION

People with IBD are more likely to present with a wide range of common infections. Health professionals and people with IBD should remain vigilant for infections, particularly when using systemic corticosteroids, immunotherapies or biologic agents.

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov (NCT03835780).

Lessons from my Elders on Recruitment and Retention into Health Research

In this brief report, the author shares lessons from Loretta Jones, MA and William Jenkins, PhD, two elders who shaped her research with communities that occupy intersecting marginalized categories. These lessons were echoed and amplified by the community panelists at the RCMAR workshop on recruitment and retention of diverse elders. They include centering the priorities of communities themselves, helping community members envision the types of positive transformations that research can help bring about, engaging and valuing the contributions of diverse sectors of the community, and recognizing the desire of aging individuals and communities to leave a legacy. Because heath care, research, and governmental institutions have engendered so much mistrust in racial/ethnic minority communities, researchers must learn first the particular histories and experience of the populations they intend to study. Equipped with this knowledge, cultural humility, and a willingness to listen, researchers can then use these strategies to earn the trust necessary for successful recruitment and retention in research.