Review/overview of pain in sickle cell disease

Deciphering Pain Experience in Adult Patients With Sickle Cell Disease: A Network Analysis of Pain-Related Factors in a Single French Sickle Cell Centre

BACKGROUND

Sickle cell disease (SCD) is the most prevalent inherited haemoglobinopathy characterised by chronic pain with acute painful episodes due to vaso-occlusion. The effective management of pain by adults with SCD influences their health outcomes. Opioids remain essential for most pain syndromes, but non-pharmacological interventions are preferred for daily pain due to the risk of addiction. However, their effectiveness is variable. Understanding the underlying processes associated with pain is crucial for developing more effective non-pharmacological strategies. This study aimed to enhance comprehension of the pain mechanisms in SCD to identify potential areas of action for effective non-pharmacological interventions.

METHOD

An evaluation was conducted on the severity and interference of pain, pain-related cognitions and emotions. We used network analysis to simultaneously examine the intricate relationships between these variables.

RESULTS

A pain intensity exceeding 4 at a steady state distinguishes a subgroup at elevated risk of negative pain-related emotions and cognitions. The network analysis revealed intricate interconnections, with three distinct subgroups of variables mimicking the Neuromatrix model (cognitive-evaluative, motivational-affective and sensory-discriminative subgroups). The derived directed acyclic graph suggests potential mechanisms between these three subgroups, with catastrophising having a pivotal role.

CONCLUSION

This study extends previous research by providing a comprehensive network analysis of pain-related variables in SCD, offering novel insights into the complex interplay between pain experience, cognitions and emotions. These findings have important clinical implications, as they suggest that targeting dysfunctional pain cognitions and/or negative emotions may be beneficial for improving pain management and quality of life in SCD.

SIGNIFICANCE STATEMENT

This study was the first to use network analyses to understand simultaneously multiple relationships between variables referring to pain, and pain-related negative emotions and cognitions in adults with SCD. Findings, providing support to the Neuromatrix model, offer novel insight to better understand pain and the associated negative emotions and cognition in SCD. The derived directed acyclic graph explored potential underlying psychological processes associated with pain that could be specifically targeted by future effective psychological interventions.

Factors associated with the occurrence of leg ulcers in people with sickle cell disease: A case-control study

AIM

To identify factors associated with the occurrence of leg ulcers in people with sickle cell disease.

METHODS

Unpaired case-control study, conducted in 11 specialized services, between August 2019 and April 2020. The convenience sample consisted of 262 people over 18 years of age, diagnosed with sickle cell disease, with 190 controls and 72 cases. To evaluate the possible factors associated with the occurrence of ulcers, both univariate and multivariate binary logistic regression models were used.

FINDINGS

The factors associated with the occurrence of leg ulcers were previously healed ulcers (odds ratio 48.48), presence of edema in the lower limbs (5.75), use of antibiotics in the last six months (3.08), daily rest (4.59), and use of compression stockings (6.24). Overweight (0.16), physical leisure (0.33), and domestic (0.37) activities were associated with a lower chance of occurrence of ulcers.

CONCLUSION

Identifying the factors that increase the likelihood of leg ulcers occurring in people with sickle cell disease adds to our knowledge of the subject, especially by determining factors that mitigate the occurrence of ulcers and that go beyond clinical variables.

Folic acid supplementation in children with sickle cell disease: a randomized double-blind noninferiority cross-over trial

BACKGROUND

Children with sickle cell disease (SCD) in Canada are routinely supplemented with folic acid to provide sufficient folate for the increased demands of erythropoiesis. However, with the mandatory folic acid fortification of refined grains and pharmacotherapies that extend the lifespan of sickled red blood cells (RBC), this clinical practice is in question.

OBJECTIVES

This study aims to determine the efficacy of folic acid supplementation by measuring the effect of 12 ± 1 wk of 1 mg/d folic acid, compared with placebo, on concentrations of RBC folate (primary outcome), serum folate, and 1-carbon-related metabolites, and clinical outcomes in children with SCD.

METHODS

In this double-blind randomized controlled noninferiority cross-over trial, 31 children with SCD, aged 2-19 y, were enrolled and randomly assigned (1:1 with blocks of 4) to 1 mg/d folic acid, the current standard of care, or a placebo for 12 ± 1 wk. After a 12 ± 1 wk washout period, treatments were reversed.

RESULTS

The mean [95% confidence interval (CI)] difference in endline RBC folate concentrations across treatments was -179 (-260, -99) nmol/L, with the lower boundary of the CI exceeding noninferiority but the upper boundary not (P = 0.0001; modified intention-to-treat). There was no significant difference in the number of participants who had RBC folate deficiency after each treatment (P = 0.059). No participants presented with serum folate deficiency (<7 nmol/L). There were no significant differences observed in 1-carbon metabolite concentrations (total homocysteine, S-adenosylhomocysteine, S-adenosylmethionine, vitamin B12, or methylmalonic acid), hematological measures, nor clinical outcomes (specifically acute pain episodes or megaloblastic changes) when individuals were supplemented with folic acid in comparison with placebo.

CONCLUSIONS

Despite mandatory food fortification and advances in the medical treatment of SCD, it appears that some children with this condition may still benefit from daily folic acid supplementation. Whether this translates to improved clinical outcomes remains uncertain. This trial was registered at clinicaltrials.gov as NCT04011345 (https://clinicaltrials.gov/study/NCT04011345).

Association of Unmet Social Needs With Disease-Related Outcomes in Pediatric Patients With Sickle Cell Disease

BACKGROUND

Social determinants of health (SDoH) are socioeconomic factors that influence health and well-being, though when unmet can greatly contribute to health disparities. Individuals with sickle cell disease (SCD) are at increased risk of mortality, disability, and healthcare utilization. However, there are limited data linking specific social needs with disease outcomes in this population. Therefore, we sought to identify the unmet needs in one institution and their association with healthcare utilization.

METHODS

Children with SCD and their guardians answered demographic and SDoH questionnaires during routine Sickle Cell Clinic appointments. We defined an unmet social need as any positive answer to the SDoH questionnaire. Disease outcome variables were electronic health record (EHR)-documented emergency department (ED) visits, hospitalizations, clinic appointment attendance, and guardian-reported acute SCD events in the previous year.

RESULTS

A total of 114 parent-guardian dyads participated, with 103 having complete data to analyze. In all, 52% of subjects reported at least one unmet social need with food insecurity (36%), trouble paying utility bills (28%), and unemployment (16%) being the most prevalent. Subjects with at least one unmet need had two times the rate of ED visits and/or hospitalizations and were 1.15 times more likely to have an SCD event in the past year. However, only the association with ED visits was statistically significant (p = 0.03).

CONCLUSION

Over half of subjects reported at least one unmet need; the most common being reliable access to food, which has the potential to impact health outcomes of sickle cell patients. Furthermore, unmet social needs are linked to healthcare utilization and SCD-related complications, supporting routine screening for SDoH in this population.

Cognitive considerations for adults with sickle cell disease completing the brief pain inventory

Introduction

Accurate assessment of pain severity is important for caring for patients with sickle cell disease (SCD). The Brief Pain Inventory was developed to address limitations of previous pain-rating metrics and is available in a short form (BPI-SF). However, the BPI-SF is a self-report scale dependent on patient comprehension and interpretation of items.

Objective

To examine patterns in how patients completed the BPI-SF and determine whether incorrectly completing the BPI-SF was related to cognitive functioning or education.

Methods

A secondary analysis was completed using data from a study examining brain aging and cognitive impairment in SCD. T-tests were performed to examine whether neurocognitive function (immediate and delayed memory, visuospatial skills, attention, and language), word reading, and years of education differed based on correct BPI-SF completion.

Results

The sample (n = 71) was 43.7% male, 98.6% African American or mixed race. Of that, 53.5% had sickle cell anemia, and the mean years of education was 13.6. Overall, 21.1% of participants (n = 15) incorrectly completed the BPI-SF pain severity items, and 57.7% completed the body map item incorrectly. Those who completed the severity items incorrectly had statistically significant differences in education. Group differences in neurocognitive function were no longer significant after familywise error rates were controlled for. Literacy was not associated with error rates.

Conclusion

Education level may influence patients' ability to correctly complete the BPI-SF. Findings suggest that careful consideration is warranted for use of the BPI in patients with SCD. Recommended revisions to the BPI include simplifying the language, shortening sentence length, and clearly specifying the timeframes.

The German sickle cell disease registry reveals a surprising risk of acute splenic sequestration and an increased transfusion requirement in patients with compound heterozygous sickle cell disease HbS/β-thalassaemia and no or low HbA expression

Patients with sickle cell disease (SCD) in Germany exhibit a substantial genetic diversity in the β-globin genotype. Data collected by the national German SCD registry reflect this diversity and allowed us to analyze the phenotypes associated with different SCD genotypes. Our study focused on 90 patients with HbS/β-thalassaemia (HbS/β-thal) and compared these to patients with HbSS and HbSC. Patients with HbS/β-thal were classified into three groups: HbS/β0-thal (no HbA), HbS/β+-thal (HbA < 14%), and HbS/β++-thal (HbA≥14%). In comparison to HbSS, patients with HbS/β++-thal had higher Hb-levels, lower hemolytic activity and rarely required red blood cell transfusions. HbS/β0-thal and HbS/β+-thal closely resembled each other and are jointly referred to as HbS/β0/+-thal. Compared to HbSS, patients with HbS/β0/+-thal experienced a similar frequency of vasoocclusive crises and degree of hemolysis. However, the frequency of red blood cell transfusions (0.6 vs. 0.39/year, p = .0049) and splenic sequestration crises (42.4 vs. 15.5% of patients, p = 3.799e-05) was higher in HbS/β0/+-thal than in HbSS, but close to zero in HbS/β++-thal. In conclusion, the level of HbA expression determines the phenotype of HbS/β+-thal. HbS/β-thal expressing no or little HbA is hematologically similar to HbSS, but causes a previously unknown high risk of splenic sequestration.

Unmet Need: Mechanistic and Translational Studies of Sickle Cell Disease Pain as a Whole-Person Health Challenge

Sickle cell disease (SCD) is a lifelong monogenic, autosomal-recessive blood disease that predominantly affects individuals of African descent and those who self-identify as Black or Hispanic. Common SCD pathophysiological processes include adhesion, hemolysis, hypoxia, ischemia, oxidative stress, and vaso-occlusion, which often lead to substantial comorbidities and complications. Pain is one of the most common and significant clinical complications for individuals with SCD. Despite advancements in understanding the pathophysiology of SCD, the ways in which SCD pathophysiological processes contribute to nociception and pain signaling, processing, and perception remain largely unclear. Pain management for individuals with SCD is complex and presents unique challenges that must be considered depending on the presenting pain type (eg, acute pain episode vs chronic pain). Racism, stigma (including stigma associated with opioid use), and limited resources present additional challenges. Limited research has been conducted on major clinical features of SCD pain such as its ischemic, inflammatory, and neuropathic components; on its transition from acute to chronic form and across the lifespan; and on factors influencing SCD pain perception. Research on and management of SCD pain requires a whole-person approach, bringing together investigators from multiple disciplines such as hematologists, organ biologists, pain experts, physiologists, neuroscientists, psychologists, geneticists, microbiologists, immunologists, behavioral scientists, and clinicians. Multidisciplinary cross-training, with different platforms for information dissemination and communication, could help promote basic, mechanistic, and translational research to inform the optimization of current treatment strategies and the development of novel therapies for SCD pain. PERSPECTIVE: This review presents the research challenges and negative impact of SCD pain, a grossly understudied condition in a highly underserved population. It also highlights the barriers and opportunities in SCD pain research and could help clinicians better understand current treatment strategies from the whole-person perspective.

Increased Delta and Theta Power Density in Sickle Cell Disease Individuals with Chronic Pain Secondary to Hip Osteonecrosis: A Resting-State Eeg Study

PURPOSE

Identify the presence of a dysfunctional electroencephalographic (EEG) pattern in individuals with sickle cell disease (SCD) and hip osteonecrosis, and assess its potential associations with depression, anxiety, pain severity, and serum levels of brain-derived neurotrophic factor (BDNF).

METHODS

In this cross-sectional investigation, 24 SCD patients with hip osteonecrosis and chronic pain were matched by age and sex with 19 healthy controls. Resting-state EEG data were recorded using 32 electrodes for both groups. Power spectral density (PSD) and peak alpha frequency (PAF) were computed for each electrode across Delta, Theta, Alpha, and Beta frequency bands. Current Source Density (CSD) measures were performed utilizing the built-in Statistical nonparametric Mapping Method of the LORETA-KEY software.

RESULTS

Our findings demonstrated that SCD individuals exhibited higher PSD in delta and theta frequency bands when compared to healthy controls. Moreover, SCD individuals displayed increased CSD in delta and theta frequencies, coupled with decreased CSD in the alpha frequency within brain regions linked to pain processing, motor function, emotion, and attention. In comparison to the control group, depression symptoms, and pain intensity during hip abduction were positively correlated with PSD and CSD in the delta frequency within the parietal region. Depression symptoms also exhibited a positive association with PSD and CSD in the theta frequency within the same region, while serum BDNF levels showed a negative correlation with CSD in the alpha frequency within the left insula.

CONCLUSION

This study indicates that individuals with SCD experiencing hip osteonecrosis and chronic pain manifest a dysfunctional EEG pattern characterized by the persistence of low-frequency PSD during a resting state. This dysfunctional EEG pattern may be linked to clinical and biochemical outcomes, including depression symptoms, pain severity during movement, and serum BDNF levels.

Quality of life and psychosocial impact on patients with blood disorders: An empirical study from patients' perspectives in Saudi Arabia

STUDY PURPOSE

this study aims to analyze QOL and psychosocial impact on patients with blood disorders.

METHODS

A cross-sectional survey design is adopted in this study. The survey questionnaire included SF-36 form for measuring quality of life (QOL), along with psychosocial impact assessment scale. Adult patients with different types of blood disorders were recruited for the survey. Out of the 417 responses received, 389 were considered for data analysis and the remaining were avoided due to incomplete data.

RESULTS

In terms of psychosocial impact scales, the highest mean is observed for financial stress (4.09 ± 1.22), followed by social exclusion (3.76 ± 1.19) and relationship challenges (3.31 ± 1.18). Among the QOL scales, the highest mean was observed for pain (3.81 ± 1.17), followed by physical functioning (3.68 ± 1.12). Statistically significant differences (p < 0.05) were observed among the participants groups characterized by age and type of disorder. Strong positive correlations between social exclusion and general health (r = 0.513), as well as pain and relationship challenges (r = 0.735) were observed.

CONCLUSION

Given the existing challenges in social exclusion, poor awareness, and support there is a need to develop comprehensive and personalized treatment plans integrating physical and mental support, awareness creation, and financial support.

Sickle Cell Disease in Brazil: Current Management

Sickle cell disease (SCD) comprises inherited red blood cell disorders due to a mutation in the β-globin gene (c20A > T, pGlu6Val) and is characterized by the presence of abnormal hemoglobin, hemoglobin S, hemolysis, and vaso-occlusion. This mutation, either in a homozygous configuration or in compound states with other β-globin mutations, leads to polymerization of hemoglobin S in deoxygenated conditions, causing modifications in red blood cell shape, particularly sickling. Vaso-occlusive crisis (VOC) is the hallmark of the disease, but other severe complications may arise from repeated bouts of VOCs. SCD is considered a global health problem, and its incidence has increased in some areas of the world, particularly the Americas and Africa. Management of the disease varies according to the region of the world, mainly due to local resources and socioeconomic status. This review aimed to describe more recent data on SCD regarding available treatment options, especially in Brazil. New treatment options are expected to be available to all patients, particularly crizanlizumab, which is already approved in the country.

Evaluating the feasibility of delivering a pain management programme for adults living with sickle cell disease

Background

Pain is the prominent feature of sickle cell disease (SCD) and negatively affects quality of life. Delivery of pain management programmes (PMPs) has been suggested in clinical guidelines for pain management in SCD; however, further evidence of the feasibility and effectiveness of PMPs in this population is needed. This study explored the feasibility of delivering a sickle cell pain management programme (SCPMP) for adults within a haemoglobinopathies service.

Methods

A single arm, repeated-measures observational design was used to determine feasibility of delivering the SCPMP at one study site. Primary feasibility outcomes were recruitment, completion of treatment and outcome measures, satisfaction, credibility and acceptability to participants. Secondary feasibility outcomes were treatment outcomes and processes, frequency of vaso-occlusive crisis (VOC) and healthcare utilisation.

Results

Four of five feasibility criteria were met. Annual recruitment of eight participants to a SCPMP was not achieved. Twenty-nine people began a SCPMP during the study period. Twenty-five (86.2%) participants attended ≥5/8 sessions and 21(84%) programme completers provided all end of programme questionnaires. Mean scores of >7 on ten-point scales were seen across satisfaction and credibility questions. At least moderate (Hedges g >0.5) effect sizes were seen in pre-post SCPMP measures of pain interference, anxiety, depression, self-efficacy, pain-related worry and acceptance. A small (Hedges g 0.4) effect size was seen in HRQoL. Following SCPMP attendance, mean frequency of self-reported VOC and hospital admissions reduced.

Conclusions

This study suggests that, given an adequate source of referrals, a SCPMP is feasible to deliver and appears acceptable and credible to participants. Exploration of influences on recruitment, such as barriers to group interventions, would be illuminating, prior to investigating feasibility of an adequately powered randomised-controlled trial.

Malnutrition in sickle cell anemia: Prevalence, impact, and interventions: A Review

Sickle Cell Anemia (SCA) is a hereditary hemoglobinopathy characterized by chronic hemolytic anemia, vaso-occlusive events, and a wide range of clinical complications. Malnutrition, often an underexplored aspect of this complex condition, plays a critical role in disease management and overall patient well-being. This publication provides a comprehensive review of the prevalence, impact, and interventions related to malnutrition in individuals with SCA. A thorough literature review reveals the multifaceted challenges faced by SCA patients in maintaining adequate nutrition. The pathophysiology of SCA, involving chronic inflammation, oxidative stress, and hypermetabolism, contributes to increased nutritional requirements and altered dietary patterns. Factors such as reduced appetite, nutrient malabsorption, dietary restrictions, and socioeconomic disparities further exacerbate the risk of malnutrition. Malnutrition is a prevalent issue among individuals with SCA, affecting patients of different age groups and disease severities. Nutritional deficiencies, including vitamins, minerals, and essential nutrients, are common in this population. The impact of malnutrition on disease outcomes is significant, with associations between nutrient status and complications such as pain crises, infections, and impaired quality of life. This paper also reviews nutritional interventions aimed at addressing malnutrition in SCA patients. While dietary counseling, supplementation, and personalized nutrition plans have shown promise in improving nutritional status, challenges such as patient adherence and access to healthcare must be addressed to optimize their effectiveness.

Management of diabetes mellitus patients with sickle cell anemia: Challenges and therapeutic approaches

The coexistence of diabetes mellitus (DM) and sickle cell anemia (SCA) poses significant challenges in clinical management due to the complex interactions and overlapping complications associated with both conditions. Managing diabetes in individuals with SCA requires a comprehensive approach that addresses the unique physiological and pathological aspects of both diseases. This paper reviews the challenges encountered in the management of DM in patients with SCA and explores therapeutic strategies and approaches to optimize patient care. Challenges in the management of DM in individuals with SCA stem from several factors, including the impact of hemoglobin variants on glycemic control assessment, increased susceptibility to infections, altered immune response, and complications associated with both diseases. Moreover, the coexistence of SCA and DM heightens the susceptibility to infections due to compromised immune function, emphasizing the need for vigilant preventive measures, including vaccinations and close monitoring for infectious complications. Close collaboration among healthcare providers specializing in diabetes, hematology, and other relevant fields is crucial for developing comprehensive care plans. Individualized treatment strategies that balance glycemic control, pain management, and preventive care are essential to mitigate complications and optimize the overall health outcomes of patients with both DM and SCA. In conclusion, managing diabetes in the context of SCA necessitates a nuanced and patient-centered approach. By addressing the challenges and employing tailored therapeutic strategies, healthcare providers can improve the quality of life and health outcomes for individuals affected by both conditions.

Unraveling the Complexity of Vaso-Occlusive Crises in Sickle Cell Disease: Insights from a Resource-Limited Setting

Background/Objectives: This study investigated vaso-occlusive crises (VOCs) in sickle cell disease in Lubumbashi, Democratic Republic of Congo, aiming to understand the disease complexities amidst limited resources. With sickle cell hemoglobinopathies on the rise in sub-Saharan Africa, this nine-year study explored factors associated with VOCs and hematological components. Methods: This study comprised 838 patients, analyzing VOCs and hematological changes over time. Demographic characteristics and blood composition changes were carefully categorized. A total of 2910 crises were observed and managed, with analyses conducted on severity, localization, and age groups using statistical methods. Results: The majority of crises were mild or moderate, primarily affecting osteoarticular regions. Statistical analysis revealed significant disparities in crisis intensity based on location and age. The association between blood samples and the number of comorbidities was investigated. Significant positive associations were found for all parameters, except monocytes, indicating a potential link between blood variables and complication burden. Survival analysis using Cox regression was performed to predict the probability of experiencing a second crisis. No significant effects of medication or localization were observed. However, intensity (p < 0.001), age (p < 0.001), and gender (p < 0.001) showed significant effects. Adjusted Hazard Ratios indicated increased risk with age and male gender and reduced risk with mild or severe crisis intensity compared to light. Conclusions: This research sheds light on the complexities of VOCs in resource-limited settings where sickle cell disease is prevalent. The intricate interplay between clinical, laboratory, and treatment factors is highlighted, offering insights for improved patient care. It aims to raise awareness of patient challenges and provide valuable information for targeted interventions to alleviate their burden.

Implications of climatic change on sickle cell anemia: A review

Sickle cell anemia (SCA) is a hereditary blood disorder characterized by abnormal hemoglobin, causing red blood cells to assume a sickle shape, leading to various complications. Climate change has emerged as a significant global challenge, influencing environmental conditions worldwide. This paper explores the implications of climatic variations on the prevalence, management, and outcomes of SCA. Climate change affects weather patterns, leading to altered temperatures, increased frequency of extreme weather events, and variations in humidity levels. These changes can have a profound impact on individuals living with SCA. High temperatures exacerbate the symptoms of SCA, potentially triggering painful vaso-occlusive crises due to dehydration and increased blood viscosity. Conversely, cold temperatures may induce vaso-occlusion by causing blood vessels to constrict. Changes in rainfall patterns might also affect water accessibility, which is crucial for maintaining adequate hydration, particularly in regions prone to droughts. The management of SCA is multifaceted, involving regular medical care, hydration, and avoiding triggers that could precipitate a crisis. Adverse weather events and natural disasters can disrupt healthcare infrastructure and access to essential medications and resources for SCA patients, especially in vulnerable communities. To mitigate the implications of climatic change on SCA, interdisciplinary strategies are essential. These strategies may include enhancing healthcare systems' resilience to climate-related disruptions, implementing adaptive measures to address changing environmental conditions, and promoting public awareness and education on managing SCA amidst climate variability. In conclusion, climatic variations pose significant challenges for individuals with SCA, affecting the prevalence, management, and outcomes of the disease.

Gut microbiota dysbiosis alters chronic pain behaviors in a humanized transgenic mouse model of sickle cell disease

ABSTRACT

Pain is the most common symptom experienced by patients with sickle cell disease (SCD) throughout their lives and is the main cause of hospitalization. Despite the progress that has been made towards understanding the disease pathophysiology, major gaps remain in the knowledge of SCD pain, the transition to chronic pain, and effective pain management. Recent evidence has demonstrated a vital role of gut microbiota in pathophysiological features of SCD. However, the role of gut microbiota in SCD pain is yet to be explored. We sought to evaluate the compositional differences in the gut microbiota of transgenic mice with SCD and nonsickle control mice and investigate the role of gut microbiota in SCD pain by using antibiotic-mediated gut microbiota depletion and fecal material transplantation (FMT). The antibiotic-mediated gut microbiota depletion did not affect evoked pain but significantly attenuated ongoing spontaneous pain in mice with SCD. Fecal material transplantation from mice with SCD to wild-type mice resulted in tactile allodynia (0.95 ± 0.17 g vs 0.08 ± 0.02 g, von Frey test, P < 0.001), heat hyperalgesia (15.10 ± 0.79 seconds vs 8.68 ± 1.17 seconds, radiant heat, P < 0.01), cold allodynia (2.75 ± 0.26 seconds vs 1.68 ± 0.08 seconds, dry ice test, P < 0.01), and anxiety-like behaviors (Elevated Plus Maze Test, Open Field Test). On the contrary, reshaping gut microbiota of mice with SCD with FMT from WT mice resulted in reduced tactile allodynia (0.05 ± 0.01 g vs 0.25 ± 0.03 g, P < 0.001), heat hyperalgesia (5.89 ± 0.67 seconds vs 12.25 ± 0.76 seconds, P < 0.001), and anxiety-like behaviors. These findings provide insights into the relationship between gut microbiota dysbiosis and pain in SCD, highlighting the importance of gut microbial communities that may serve as potential targets for novel pain interventions.

Vaso-occlusive crisis pain intensity, frequency, and duration: which best correlates with health-related quality of life in adolescents and adults with sickle cell disease?

ABSTRACT

In a cross-sectional analysis of baseline data from a randomized clinical trial, we studied 198 adolescents and adults aged 15+ with sickle cell disease. Interest was in assessing the relative strengths of the relationship of vaso-occlusive crisis (VOC) pain domains of intensity, frequency, and duration, with health-related quality of life (HRQOL). Variation in psychosocial, physical function, and pain expression domains of HRQOL was partially explained by frequency, intensity, and duration of VOC pain, separately and together, over and above differences in age, sex, genotype, and organ system damage. However, no single domain measure accounted for more than an additional partial R2 of 12.5% alone. Vaso-occlusive crisis pain frequency explained the most variation, when simultaneously considering VOC intensity and duration, except for stiffness , where duration was most predictive. Yet VOC pain intensity, and even VOC duration, also contributed to variability in HRQOL. We recommend that for most purposes, because all 3 VOC pain domains contribute to variability in HRQOL, all 3 domains should be assessed and interventions should be targeted to improve all 3 domains to maximize HRQOL outcomes (Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT02197845 ).

Analysis of AVPR1A, thermal and pressure pain thresholds, and stress in sickle cell disease

Aim

In patients with sickle cell disease (SCD), negative physical and emotional experiences result from intense chronic and acute pain episodes, but factors underlying these, and their interactions, are not well understood. The arginine vasopressin receptor 1a gene (AVPR1A) single nucleotide polymorphism rs10877969 has been previously associated with aspects of acute pain and stress related pain. In this study, we tested for associations between this SNP, thermal and pressure pain thresholds, clinical pain, and stress in people with SCD.

Methods

150 adults enrolled with SCD completed pain intensity measures (Average Pain Intensity, API) and the Perceived Stress Questionnaire (PSQ). Thermal and pressure pain threshold data were available from quantitative sensory testing (QST), and rs10877969 genotypes were obtained.

Results

In models adjusted for age and gender, between rs10877969 genotypes, we observed no significant differences in thermal (cold, p = 0.66; heat, p = 0.91) and mechanical (pressure, p = 0.33) pain thresholds. The association of rs10877969 with API (p = 0.09) was borderline, but non-significant with PSQ (p = 0.51). The correlation between clinical pain and environmental stress was significant, r = 0.18, p = 0.024, however, the interaction of genotype and PSQ was not significant (p = 0.63).

Conclusion

Clinical and experimental pain were not significantly associated with the rs10877969 genotype. The rs10877969 genotype did not moderate the correlation between environmental stress and clinical pain in this population. However, a trend toward a protective T allele effect on average pain rating in SCD warrants future exploration of this SNP/gene in SCD.

New Iron Metabolic Pathways and Chelation Targeting Strategies Affecting the Treatment of All Types and Stages of Cancer

There is new and increasing evidence from in vitro, in vivo and clinical studies implicating the pivotal role of iron and associated metabolic pathways in the initiation, progression and development of cancer and in cancer metastasis. New metabolic and toxicity mechanisms and pathways, as well as genomic, transcription and other factors, have been linked to cancer and many are related to iron. Accordingly, a number of new targets for iron chelators have been identified and characterized in new anticancer strategies, in addition to the classical restriction of/reduction in iron supply, the inhibition of transferrin iron delivery, the inhibition of ribonucleotide reductase in DNA synthesis and high antioxidant potential. The new targets include the removal of excess iron from iron-laden macrophages, which affects anticancer activity; the modulation of ferroptosis; ferritin iron removal and the control of hyperferritinemia; the inhibition of hypoxia related to the role of hypoxia-inducible factor (HIF); modulation of the function of new molecular species such as STEAP4 metalloreductase and the metastasis suppressor N-MYC downstream-regulated gene-1 (NDRG1); modulation of the metabolic pathways of oxidative stress damage affecting mitochondrial function, etc. Many of these new, but also previously known associated iron metabolic pathways appear to affect all stages of cancer, as well as metastasis and drug resistance. Iron-chelating drugs and especially deferiprone (L1), has been shown in many recent studies to fulfill the role of multi-target anticancer drug linked to the above and also other iron targets, and has been proposed for phase II trials in cancer patients. In contrast, lipophilic chelators and their iron complexes are proposed for the induction of ferroptosis in some refractory or recurring tumors in drug resistance and metastasis where effective treatments are absent. There is a need to readdress cancer therapy and include therapeutic strategies targeting multifactorial processes, including the application of multi-targeting drugs involving iron chelators and iron-chelator complexes. New therapeutic protocols including drug combinations with L1 and other chelating drugs could increase anticancer activity, decrease drug resistance and metastasis, improve treatments, reduce toxicity and increase overall survival in cancer patients.

Sickle cell disease chronic joint pain: Clinical assessment based on maladaptive central nervous system plasticity

Chronic joint pain (CJP) is among the significant musculoskeletal comorbidities in sickle cell disease (SCD) individuals. However, many healthcare professionals have difficulties in understanding and evaluating it. In addition, most musculoskeletal evaluation procedures do not consider central nervous system (CNS) plasticity associated with CJP, which is frequently maladaptive. This review study highlights the potential mechanisms of CNS maladaptive plasticity related to CJP in SCD and proposes reliable instruments and methods for musculoskeletal assessment adapted to those patients. A review was carried out in the PubMed and SciELO databases, searching for information that could help in the understanding of the mechanisms of CNS maladaptive plasticity related to pain in SCD and that presented assessment instruments/methods that could be used in the clinical setting by healthcare professionals who manage chronic pain in SCD individuals. Some maladaptive CNS plasticity mechanisms seem important in CJP, including the impairment of pain endogenous control systems, central sensitization, motor cortex reorganization, motor control modification, and arthrogenic muscle inhibition. Understanding the link between maladaptive CNS plasticity and CJP mechanisms and its assessment through accurate instruments and methods may help healthcare professionals to increase the quality of treatment offered to SCD patients.

Prevalence of people with sickle cell disease and leg ulcers in Brazil: Socioeconomic and clinical overview

Objective

To identify the prevalence of people with leg ulcers resulting from sickle cell disease, as well as to describe the clinical, social, economic, and demographic conditions of these people.

Method

Descriptive study, carried out at the Minas Gerais Hematology and Hemotherapy Center Foundation. The study population consisted of individuals over the age of 18 with a diagnosis of sickle cell disease in the State of Minas Gerais, Brazil. Data collection was performed from August 2019 to April 2020 through interviews. For the prevalence calculation, a census was taken of 5,379 people over the age of 18 with sickle cell disease, 77 of whom had active leg ulcers. Descriptive data analysis was performed using SPSS software (version 20.0, Chicago, IL, USA).

Results

The prevalence of people with leg ulcers in Minas Gerais, Brazil was 1.4%. Of the 72 respondents, the average age was 39 years (range 18–64 years), 41.7% were single, 48.6% said they were black, 84.7% lived in their own house, 38.9% were retired, 61.1% had an income of one minimum wage. The median years of education was 10.5, 50% cited the church as a place for leisure activities, 79.2% denied smoking. Regarding pain, the median score was 3, the median baseline hemoglobin was 7.7 g/dL, and 91.7% had the HbSS genotype. The median age of the first ulcer was 18 years, 77.8% of active ulcers were recurrent, and 59.7% had only one active ulcer. The median time of existence of the ulcer was 3 years. The ulcer prevented 80.6% of people from doing some activity. Prejudice was experienced by 48.6% of the participants.

Conclusion

The estimated prevalence of leg ulcers was lower than what it reported in the literature, however, the recurrence and the duration of ulcers were high. These findings bring reflection about the assistance to people with leg ulcer.

Prevalence of neuropathic pain in adolescents with sickle cell disease: A single-center experience

BACKGROUND

Neuropathic pain (NP) has been previously explored in adolescents with sickle cell disease (SCD). This study aims to describe the prevalence of NP in adolescents with SCD at a single institution and to explore associated risk factors.

PROCEDURE

We used the painDETECT questionnaire, one of the few pain phenotyping questionnaires validated for adolescents. We also evaluated the relationships between painDETECT scores and frequency of acute care visits and admissions for pain in the previous 12 months, and age, respectively. Patients 12-18 years old were surveyed from June to July 2019. A retrospective approach was used to answer the remaining research questions.

RESULTS

Eighty-one and seven surveys were completed in the outpatient and inpatient settings, respectively. PainDETECT scores suggestive of NP were more prevalent in inpatient surveys than in outpatient surveys. The difference between the mean painDETECT scores of each group was significant when using a general linear mixed model. Most inpatients surveyed had ≥3 pain events in the previous 12 months. Further, older age and increased number of pain events in the previous 12 months were independently associated with higher painDETECT scores.

CONCLUSIONS

Overall, in our opinion, NP is not being evaluated for and treated sufficiently in pediatric SCD, especially in the setting of inpatient acute vaso-occlusive crisis. Age and number of acute pain events/admissions in the previous 12 months can be used to identify patients likely to be at risk for NP. It is important to continue to identify NP and develop NP-targeting treatment plans.

Nursing Education for the Acute Care Nurse on Pain Mechanisms of Sickle Cell Disease

Background It is unknown whether nurses' knowledge about pain among patients with sickle cell disease (SCD) reflects the current standard of care. The authors evaluated changes in nurses' knowledge and simulated practice behavior after a continuing education program. Method Inpatient nurses completed an e-learning program on SCD pain; a pretest and a posttest with the same 10 questions; and two patient cases with four pain intervention options at the posttest. Results On the pretest, the mean percentage of correct answers was 83% (SD = 13%). The mean percentage of correct answers increased by 12% (p < .0001) on the posttest. For the first simulated patient case, 100% (n = 31) of the nurses selected an appropriate pain intervention option based on the patient-reported pain score. For the second simulated patient case, 84% (n = 26) did so. Conclusion Increased knowledge does not always translate into simulated practice change. The reasons for this are unknown, but they could include implicit bias from exposure to patients who have high use of acute care, although the minority of patients with SCD fit this description. [J Contin Educ Nurs. 2022;53(3):137-144.].

Main Complications during Pregnancy and Recommendations for Adequate Antenatal Care in Sickle Cell Disease: A Literature Review

Sickle cell disease (SCD) is the most common monogenic disease worldwide, with a variable prevalence in each continent. A single nucleotide substitution leads to an amino-acid change in the β-globin chain, altering the normal structure ofhemoglobin, which is then called hemoglobin S inherited in homozygosity (HbSS) or double heterozygosity (HbSC, HbSβ), and leads to chronic hemolysis, vaso-occlusion, inflammation, and endothelium activation. Pregnant women with SCD are at a higher risk of developing maternal and perinatal complications. We performed a narrative review of the literature considering SCD and pregnancy, the main clinical and obstetrical complications, the specific antenatal care, and the follow-up for maternal and fetal surveillance. Pregnant women with SCD are at a higher risk of developing clinical and obstetric complications such as pain episodes, pulmonary complications, infections, thromboembolic events, preeclampsia, and maternal death. Their newborns are also at an increased risk of developing neonatal complications: fetal growth restriction, preterm birth, stillbirth. Severe complications can occur in patients of any genotype. We concluded that SCD is a high-risk condition that increases maternal and perinatal morbidity and mortality. A multidisciplinary approach during pregnancy and the postpartum period is key to adequately diagnose and treat complications.

A polygenic score for acute vaso-occlusive pain in pediatric sickle cell disease

Individuals with monogenic disorders can experience variable phenotypes that are influenced by genetic variation. To investigate this in sickle cell disease (SCD), we performed whole-genome sequencing (WGS) of 722 individuals with hemoglobin HbSS or HbSβ0-thalassemia from Baylor College of Medicine and from the St. Jude Children's Research Hospital Sickle Cell Clinical Research and Intervention Program (SCCRIP) longitudinal cohort study. We developed pipelines to identify genetic variants that modulate sickle hemoglobin polymerization in red blood cells and combined these with pain-associated variants to build a polygenic score (PGS) for acute vaso-occlusive pain (VOP). Overall, we interrogated the α-thalassemia deletion -α3.7 and 133 candidate single-nucleotide polymorphisms (SNPs) across 66 genes for associations with VOP in 327 SCCRIP participants followed longitudinally over 6 years. Twenty-one SNPs in 9 loci were associated with VOP, including 3 (BCL11A, MYB, and the β-like globin gene cluster) that regulate erythrocyte fetal hemoglobin (HbF) levels and 6 (COMT, TBC1D1, KCNJ6, FAAH, NR3C1, and IL1A) that were associated previously with various pain syndromes. An unweighted PGS integrating all 21 SNPs was associated with the VOP event rate (estimate, 0.35; standard error, 0.04; P = 5.9 × 10-14) and VOP event occurrence (estimate, 0.42; standard error, 0.06; P = 4.1 × 10-13). These associations were stronger than those of any single locus. Our findings provide insights into the genetic modulation of VOP in children with SCD. More generally, we demonstrate the utility of WGS for investigating genetic contributions to the variable expression of SCD-associated morbidities.

Targeting Neutrophil Adhesive Events to Address Vaso-Occlusive Crisis in Sickle Cell Patients

Neutrophils are essential to protect the host against invading pathogens but can promote disease progression in sickle cell disease (SCD) by becoming adherent to inflamed microvascular networks in peripheral tissue throughout the body. During the inflammatory response, leukocytes extravasate from the bloodstream using selectin adhesion molecules and migrate to sites of tissue insult through activation of integrins that are essential for combating pathogens. However, during vaso-occlusion associated with SCD, neutrophils are activated during tethering and rolling on selectins upregulated on activated endothelium that line blood vessels. Recently, we reported that recognition of sLex on L-selectin by E-selectin during neutrophil rolling initiates shear force resistant catch-bonds that facilitate tethering to endothelium and activation of integrin bond clusters that anchor cells to the vessel wall. Evidence indicates that blocking this important signaling cascade prevents the congestion and ischemia in microvasculature that occurs from neutrophil capture of sickled red blood cells, which are normally deformable ellipses that flow easily through small blood vessels. Two recently completed clinical trials of therapies targeting selectins and their effect on neutrophil activation in small blood vessels reveal the importance of mechanoregulation that in health is an immune adaption facilitating rapid and proportional leukocyte adhesion, while sustaining tissue perfusion. We provide a timely perspective on the mechanism underlying vaso-occlusive crisis (VOC) with a focus on new drugs that target selectin mediated integrin adhesive bond formation.

PROFILE OF WOMEN WITH LEG ULCERS DUE TO SICKLE CELL DISEASE

Objective: to characterize the profile of women with leg ulcers resulting from sickle cell disease treated at a public health institution in Brazil. Method: historical cohort study conducted in the outpatient sector with a sample of women with sickle cell disease and leg ulcer, followed from 1998 to 2014. The data were extracted from the medical record and included sociodemographic, clinical and ulcer-related variables, and underwent descriptive statistical analysis. Results: of the 17 women, 64.7% were cured, 58.8% were aged between 30 and 39 years, 64.7% declared themselves brown, 70.6% were without partners, 41.2% had incomplete elementary education, 52, 9% had an income of 2 to 3 minimum wages, 70.6% were eutrophic and 82.4% used vitamin supplements. Women had a total of 29 ulcers, 52.9% had a single ulcer, 41.4% were located in the malleolar region, 55.17% were between 2 and 36 months, all classified as stage 3. The treatment was with coverings and Unna’s boot. Conclusion: the women received care from specialist nurses and most were cured with up to eight months of follow-up, which required a nursing consultation, including clinical evaluation, topical treatment and application of compression therapy.

PERFIL DE MULHERES COM ÚLCERAS DA PERNA DECORRENTES DE DOENÇA FALCIFORME

Objetivo:caracterizar o perfil de mulheres com úlceras da perna decorrentes da doença falciforme atendidas em uma instituição pública de saúde do Brasil. Método: estudo de coorte histórica realizado no setor ambulatorial com amostra de mulheres com doença falciforme e úlcera da perna, acompanhadas de 1998 a 2014. Os dados foram extraídos do prontuário e contemplaram variáveis sociodemográficas, clínicas e relacionadas à úlcera, e passaram por análise estatística descritiva. Resultados: das 17 mulheres, 64,7% obtiveram cura, 58,8% tinham idade entre 30 e 39 anos, 64,7% se autodeclaram pardas, 70,6% estavam sem parceiros, 41,2% possuíam ensino fundamental incompleto, 52,9% tinham renda de 2 a 3 salários mínimos, 70,6% eram eutróficas e 82,4% faziam uso de suplementos vitamínicos. As mulheres apresentaram o total de 29 úlceras, 52,9% tinham úlcera única, 41,4% localizadas na região maleolar, 55,17% com existência entre 2 e 36 meses, todas classificadas em estágio 3. O tratamento foi com coberturas e bota de Unna. Conclusão: as mulheres receberam cuidados de enfermeiros especialistas e a maioria obteve a cura com até oito meses de acompanhamento que demandou a consulta de enfermagem, contemplando a avaliação clínica, o tratamento tópico e aplicação da terapia de compressão.

Considerations for Cannabis Use to Treat Pain in Sickle Cell Disease

Pain in Sickle Cell Disease (SCD) is a major comorbidity and unique with acute pain due to recurrent and episodic vaso-occlusive crises as well as chronic pain, which can span an individual's entire life. Opioids are the mainstay treatment for pain in SCD. Due to recent health crises raised by adverse effects including deaths from opioid use, pain management in SCD is adversely affected. Cannabis and its products are most widely used for pain in multiple conditions and also by patients with SCD on their own. With the availability of "Medical Cannabis" and approval to use cannabis as medicine across majority of States in the United States as well as over-the-counter preparations, cannabis products are being used increasingly for SCD. The reliability of many of these products remains questionable, which poses a major health risk to the vulnerable individuals seeking pain relief. Therefore, this review provides up to date insights into available categories of cannabis-based treatment strategies, their mechanism of action and pre-clinical and clinical outcomes in SCD. It provides evidence for the benefits and risks of cannabis use in SCD and cautions about the unreliable and unvalidated products that may be adulterated with life-threatening non-cannabis compounds.

Iron and Chelation in Biochemistry and Medicine: New Approaches to Controlling Iron Metabolism and Treating Related Diseases

Iron is essential for all living organisms. Many iron-containing proteins and metabolic pathways play a key role in almost all cellular and physiological functions. The diversity of the activity and function of iron and its associated pathologies is based on bond formation with adjacent ligands and the overall structure of the iron complex in proteins or with other biomolecules. The control of the metabolic pathways of iron absorption, utilization, recycling and excretion by iron-containing proteins ensures normal biologic and physiological activity. Abnormalities in iron-containing proteins, iron metabolic pathways and also other associated processes can lead to an array of diseases. These include iron deficiency, which affects more than a quarter of the world's population; hemoglobinopathies, which are the most common of the genetic disorders and idiopathic hemochromatosis. Iron is the most common catalyst of free radical production and oxidative stress which are implicated in tissue damage in most pathologic conditions, cancer initiation and progression, neurodegeneration and many other diseases. The interaction of iron and iron-containing proteins with dietary and xenobiotic molecules, including drugs, may affect iron metabolic and disease processes. Deferiprone, deferoxamine, deferasirox and other chelating drugs can offer therapeutic solutions for most diseases associated with iron metabolism including iron overload and deficiency, neurodegeneration and cancer, the detoxification of xenobiotic metals and most diseases associated with free radical pathology.