Headaches Attributed to Disorders of Homeostasis

Headaches attributed to disorders of homeostasis include those different headache types associated with metabolic and systemic diseases. These are headache disorders occurring in temporal relation to a disorder of homeostasis including hypoxia, high altitude, airplane travel, diving, sleep apnea, dialysis, autonomic dysreflexia, hypothyroidism, fasting, cardiac cephalalgia, hypertension and other hypertensive disorders like pheochromocytoma, hypertensive crisis, and encephalopathy, as well as preeclampsia or eclampsia. The proposed mechanism behind the causation of these headache subtypes including diagnostic criteria, evaluation, treatment, and overall management will be discussed.

A16 UNMET HEALTHCARE NEEDS AMONG PEOPLE WITH INFLAMMATORY BOWEL DISEASE: A NATIONAL CROSS-SECTIONAL POPULATION-REPRESENTATIVE STUDY

Background

Inflammatory bowel disease (IBD) is a chronic inflammatory disease primarily affecting the gastrointestinal tract. Despite treatment with the current standards of care, many IBD patients experience relapsing, remitting, and disabling bowel symptoms and significant disease complications. Ensuring patients have adequate access to high quality multidisciplinary healthcare is vital for the short- and long-term wellbeing of IBD patients.

Purpose

(1) Compare unmet healthcare needs of people with and without IBD. (2) Determine whether accessing regular medical care mediates the association between IBD and unmet healthcare needs. (3) Describe the reasons for unmet healthcare needs among people with and without IBD.

Method

We used the 2014 Canadian Community Health Survey, a population-representative national cross-sectional survey conducted by Statistics Canada. Respondents with a non-IBD bowel disorder or aged 18 or younger were excluded. Survey weights were used for descriptive statistics. We used multilevel logistic regression to compare perceived unmet healthcare needs among individuals with and without IBD, clustering by health region and controlling for age, immigration status, race, home ownership, marital status, annual household income, education level, and number of chronic conditions (0, 1, 2+). In a second model, we additionally controlled for having a regular family doctor, having consulted a specialist, and having consulted a psychologist to assess if regularly accessing medical care mediated the association between IBD and unmet healthcare needs. Individuals reporting unmet healthcare needs were asked about the reasons for their unmet healthcare needs. Responses are summarized with weighted percentages, plotted in a bar graph.

Result(s)

Among the 690 IBD and 62,832 non-IBD eligible survey respondents, 16.7% of people with IBD had an unmet healthcare need within the past 12 months, compared with 10.3% of those without IBD (OR 1.39, 95% CI 1.12 to 1.74). Additionally adjusting for regular access to medical care slightly attenuated the association between IBD and unmet healthcare needs (OR 1.29, 95% CI 1.03 to 1.62). Reasons for unmet healthcare needs differed among those with and without IBD (Figure). Specifically, doctors believing that care was unnecessary and the cost of care were more likely to be the reason people with IBD had an unmet healthcare need.

Image

Conclusion(s)

People with IBD are more likely to have an unmet healthcare need that was partially mediated by access to healthcare professionals. Our work highlights the need for further research into the types of unmet healthcare needs experienced by people living with IBD. This underscores the need for multidisciplinary healthcare teams to address the increased burden of unmet healthcare needs in the IBD population.

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None

Disclosure of Interest

G. Postill: None Declared, E. Benchimol Consultant of: Hoffman La-Roche Limited and Peabody & Arnold LLP for matters unrelated to medications used to treat inflammatory bowel disease. Dr. Benchimol has also acted as a consultant for McKesson Canada and the Dairy Farmers of Ontario for matters unrelated to medications used to treat inflammatory bowel disease., J. Im: None Declared, A. Tang: None Declared, E. Kuenzig: None Declared

A177 RISK OF VENOUS THROMBOEMBOLISM IN COVID-19 PATIENTS WITH INFLAMMATORY BOWEL DISEASE: A POPULATION-BASED MATCHED COHORT STUDY

Background

Venous thromboembolism (VTE), is associated with significant morbidity and mortality. Inflammation increases the risk of VTE, and it is a well-recognised complication of both inflammatory bowel disease (IBD) and COVID-19.

Purpose

To compare the risk of VTE among individuals with and without IBD following a positive COVID-19 test.

Method

Using health administrative data from Ontario, Canada we conducted a retrospective matched cohort study.All Ontario residents with a positive SARS-CoV-2 PCR test between January 1,2020 and December 30,2021 who had been diagnosed with IBD prior to their COVID-19 infection (identified using a validated algorithm) were matched to 5 individuals without IBD based on year of birth, sex, mean neighbourhood income quintile, date of positive COVID-19 test, and rural/urban residence. Individuals with a cancer diagnosis in the 5 years prior to their first COVID-19 positive test were excluded. Individuals were followed from positive COVID-19 PCR test until VTE event, death, migration out of Ontario or March 31, 2022.VTEs were identified from emergency department or hospitalization data using ICD-10 codes. Incidence rate of VTEs among individuals with IBD were assessed at 1, 6 and 12 months. Proportional cause-specific hazards models compared the risk of VTEs in people with and without IBD, treating death as a competing risk and controlling for vaccination status (2^nd dose ≥14 days prior to positive COVID-19 test) and a history of VTE (VTE in the 5 years prior to infection).

Result(s)

There were 4293 people with IBD (44% Crohn’s disease, mean age ±SD 46.1±17.2 y) matched to 20,207 with out IBD (mean age 45.3±16.8 y) with a positive SARS-CoV-2 PCR test. Within 1 month of a positive COVID-19 test, the crude incidence rate of VTE in individuals with IBD was 4.77(95%CI, 4.75-4.80) per 100,000 person-days compared to 8.25(95%CI, 8.20-8.30) per 100,000 among people without IBD.Within 6 months, these rates were 1.86(95%CI, 1.86-1.87) and 2.12(95%CI, 2.11-2.12) per 100,000 person-days among people with and without IBD, respectivley. Within 12 months, these rates were 1.59(95% CI, 1.58-1.59) and 1.42(95% CI, 1.42-1.42) per 100,000 person-days among people with and without IBD, respectively.After adjusting for vaccination status and history of VTE there was no difference in the risk of VTE for people with and without IBD (HR 1.08, 95%CI, 0.64 to 1.83).

Conclusion(s)

IBD patients with COVID-19 were not more likely to experience a VTE infection compared with the general popluation. The risk of VTE was highest soon after COVID-19 and declined thereafter.

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None

Disclosure of Interest

None Declared

Perceptions and correlates of distress due to the COVID-19 pandemic and stress management strategies among people with diabetes: a mixed methods study

Background

Greater risk of adverse health outcomes and public health measures have increased distress among people with diabetes during the coronavirus-2019 (COVID-19) pandemic. The objectives of this study were to explore how the experiences of people with diabetes during the COVID-19 pandemic differ according to sociodemographic characteristics and identify diabetes-related psychosocial correlates of COVID distress.

Methods

Patients with type 1 or 2 diabetes were recruited from clinics and community health centres in Toronto, Ontario, as well as patient networks. Participants were interviewed to explore the experiences of people with diabetes with varied sociodemographic and clinical identities, with respect to wellness (physical, emotional, social, financial, occupational), level of stress and management strategies. Multiple linear regression was used to assess the relationships between diabetes distress, diabetes self-efficacy and resilient coping with COVID distress.

Results

Interviews revealed that specific aspects of psychosocial wellness affected by the pandemic, and stress and illness management strategies utilized by people with diabetes differed based on socioeconomic status, gender, type of diabetes and race. Resilient coping (β=−0.0517; 95% confidence interval [CI], −0.0918 to −0.0116; p=0.012), diabetes distress (β=0.0260; 95% CI, 0.0149 to 0.0371; p<0.0001) and diabetes self-efficacy (β=−0.0184; 95% CI, −0.0316 to −0.0052; p=0.007) were significantly associated with COVID distress.

Conclusions

Certain subgroups of people with diabetes have experienced a disproportionate amount of COVID distress. Assessing correlates of COVID distress among people with diabetes will help inform interventions such as diabetes self-management education to address the psychosocial distress caused by the pandemic.

The protective association between statins use and adverse outcomes among COVID-19 patients: A systematic review and meta-analysis

INTRODUCTION

Statins may reduce a cytokine storm, which has been hypothesized as a possible mechanism of severe COVID-19 pneumonia. The aim of this study was to conduct a systematic review and meta-analysis to report on adverse outcomes among COVID-19 patients by statin usage.

METHODS

Literatures were searched from January 2019 to December 2020 to identify studies that reported the association between statin usage and adverse outcomes, including mortality, ICU admissions, and mechanical ventilation. Studies were meta-analyzed for mortality by the subgroups of ICU status and statin usage before and after COVID-19 hospitalization. Studies reporting an odds ratio (OR) and hazard ratio (HR) were analyzed separately.

RESULTS

Thirteen cohorts, reporting on 110,078 patients, were included in this meta-analysis. Individuals who used statins before their COVID-19 hospitalization showed a similar risk of mortality, compared to those who did not use statins (HR 0.80, 95% CI: 0.50, 1.28; OR 0.62, 95% CI: 0.38, 1.03). Patients who were administered statins after their COVID-19 diagnosis were at a lower risk of mortality (HR 0.53, 95% CI: 0.46, 0.61; OR 0.57, 95% CI: 0.43, 0.75). The use of statins did not reduce the mortality of COVID-19 patients admitted to the ICU (OR 0.65; 95% CI: 0.26, 1.64). Among non-ICU patients, statin users were at a lower risk of mortality relative to non-statin users (HR 0.53, 95% CI: 0.46, 0.62; OR 0.64, 95% CI: 0.46, 0.88).

CONCLUSION

Patients administered statins after COVID-19 diagnosis or non-ICU admitted patients were at lower risk of mortality relative to non-statin users.

Oral cannabinoid for the prophylaxis of chemotherapy-induced nausea and vomiting-a systematic review and meta-analysis

INTRODUCTION

Chemotherapy-induced nausea and vomiting (CINV) is a burdensome adverse event frequently associated with chemotherapy treatment of cancer. Evidence suggests that cannabinoid CB2 receptors are present in brainstem neurons, and thus, there may exist a role for cannabinoids to counter CINV. The aim of this paper is to conduct a systematic review and meta-analysis of the efficacy and safety of oral cannabinoids compared with other treatments as documented in randomized controlled trials (RCTs).

METHODS

A literature search was conducted using Ovid MEDLINE up until December 31, 2018; Embase Classic and Embase up until 2018 week 53; and Cochrane Central Register of Controlled Trials up until November 2018. Study data were extracted and included in this meta-analysis if they reported on at least one of the following efficacy endpoints: no nausea and no vomiting, no nausea, and no vomiting. The Mantel-Haenszel method and random effects analysis model were used, to generate odds ratio (OR) and accompanying 95% confidence intervals (CI).

RESULTS

In the setting of prophylactic treatment against both nausea and vomiting, oral cannabinoid was more efficacious than placebo or other studied antiemetic treatments. When controlling for vomiting, oral cannabinoid was equally as efficacious as others. Against nausea, oral cannabinoid was equally as effective as other treatments. A greater percentage of patients administered oral cannabinoid for CINV experienced dysphoria, euphoria, and sedation.

CONCLUSION

Although there exists some evidence suggesting that oral cannabinoids may have a role in controlling for emesis from a neurophysiological perspective, these conclusions are currently not mirrored in the published RCTs to date. However, there exists only a limited number of RCTs, comparisons with older treatment regimens and a lack of standard reporting practice across published literature. Further RCTs should investigate the efficacy and safety of oral cannabinoids, to secure a better picture of the efficacy of oral cannabinoids against CINV.

Inter-rater reliability in performance status assessment between clinicians and patients: a systematic review and meta-analysis

INTRODUCTION

Performance status is an essential consideration for clinical practice and for patient eligibility for clinical trials in oncology. Assessment of performance status is traditionally done by clinicians, but there is an increasing interest in patient-completed assessment. The aim of this systematic review and meta-analysis was to summarise inter-rater concordance between patient and clinician ratings of performance status.

METHODS

A search strategy was developed and executed in the databases of Ovid MEDLINE, Embase and Cochrane Central Register of Controlled Trials, from inception until 15 August 2019. Articles were eligible for inclusion if there was mention of both (1) use of performance status tool Karnofsky Performance Status (KPS) or Eastern Cooperative Oncology Group Performance Status (ECOG), and (2) assessment of performance status by both clinicians and patients. Pearson correlation coefficients were calculated for each study and were meta-analysed according to a random-effect analysis model. Analyses were conducted using Comprehensive Meta-Analysis (V.3) by Biostat.

RESULTS

Sixteen articles were included in our review, reporting on a cumulative sample size of 6619 patients. The quality of evidence was moderate, as determined by the GRADE tool.Concordance ranged from fair to moderate for both the KPS and ECOG tools. The Pearson correlation coefficient was 0.449 for KPS and 0.584 for ECOG.

CONCLUSIONS

There is fair to moderate concordance of patient and clinician performance status ratings. Future studies should examine the reasoning behind clinician and patient ratings to better understand discrepancies between ratings.

Single vs multiple fraction palliative radiation therapy for bone metastases: Cumulative meta-analysis

INTRODUCTION

There has been a long-standing debate regarding the efficacy of single fraction radiotherapy (SFRT) compared to multiple fraction radiotherapy (MFRT); many systematic reviews and meta-analyses have been conducted to resolve the debate and suggested SFRT is equally as effective as MFRT. Given the adequate amalgamated sample size that exists, it is difficult to appreciate the need for further RCTs. The aim of this paper was to conduct a cumulative meta-analysis to determine whether further trials will be of value to the meta-conclusion. This paper also assessed publication quality.

METHODS

A total of 29 studies were used in our meta-analysis. Comprehensive Meta-Analysis (Version 3) by Biostat was used to conduct a cumulative meta-analysis. The Cochrane Risk of Bias assessment tool was employed to assess study quality of the included RCTs. Funnel plots were generated using Review Manager (RevMan 5.3) by Cochrane IMS, to visually assess for publication bias.

RESULTS

All but one endpoint, overall response rates in assessable patients, maintained the same meta-conclusion over publication time; published studies did not change the amalgamated scientific conclusion of existing literature. Additional studies have simply confirmed pre-existing conclusions and refined the point estimate of the efficacy estimate. The majority of included studies have low risk of bias.

CONCLUSION

In conclusion, the meta-conclusion has remained consistent over time - SFRT is equally as efficacious as MFRT. Recent studies have had little impact on the overall conclusion, and given the vast amount of resources to execute a randomized trial, future resources should not be used to repeat these studies, and can be better allocated to test other hypotheses.

Identification of a new HLA-A*11 allele, A*11:251N

The new allele, A*11:251N, differs from A*11:01:01 by insertion of two nucleotides at position 204-205.

Identification of the novel HLA-B*15:18:01:04 in a Korean individual

HLA-B*15:18:01:04 differs from HLA-B*15:18:01:02 by single nucleotide substitution at position 2176 (G > A).

HLA-B*40:302, a novel allele identified by sequence-based typing in a Korean individual

B*40:302 differs from B*40:02:01:01 by a single nonsynonymous nucleotide substitution at codon 81 (CCG→CTG).

Identification of a novel allele, HLA-A*02:01:131, by full-length genomic sequencing

The HLA-A*02:01:131 allele differs by a single nucleotide at codon 236 compared with HLA-A*02:01:01:01.

HLA-DPB1*519:01, a new allele identified by sequence-based typing in a Korean individual

The new allele DPB1*519:01 showed one nucleotide difference with DPB1*13:01:01 at codon 234 (GTG/ATG).

Identification of a novel allele, HLA-C*02:02:33, by full-length genomic sequencing

The HLA-C*02:02:33 allele differs by a single nucleotide at codon 215 compared with HLA-C*02:02:02:01.

A novel allele, HLA-C*14:02:01:03, identified by full-length genomic sequencing

The HLA-C*14:02:01:03 differs by a single nucleotide at intron 5 (2157 C>T) compared with C*14:02:01:01.

Identification of a novel allele, HLA-C*01:135, by full-length genomic sequencing

The HLA-C*01:135 allele differs by a single nucleotide at codon 265 compared with HLA-C*01:02:01:01.

Identification of a novel HLA-B allele, HLA-B*55:81

The new allele, B*55:81, differs from B*55:02:01:02 by 2 nucleotide substitutions in codon 116 (TTA → TAC).

Novel deletion mutation of HLA-B*40:02 gene in acquired aplastic anemia

Despite prevalence of clonal evolution in patients with aplastic anemia (AA), somatic mutation of human leukocyte antigen (HLA) gene is rarely reported. Herein, we reported a case of acquired AA (aAA) harboring a new four-base-pair deletion mutation within exon 4 of HLA-B*40:02 leading to frameshift and premature stop codon. The HLA-B*40:02 mutant allele was detected in the patient's peripheral blood sample not in patient's buccal epithelial cells. The patient received allogenic hematopoietic stem cell transplantation (HSCT) from HLA-matched sibling donor. On day 30 after HSCT, the mutant HLA allele was not detected by high-resolution sequence-based HLA typing. Serial chimerism analyses showed mixed chimeric status indicative of coexisting donor and recipient hematopoietic cells. Our data could provide additional support in view of pathophysiology of aAA that somatic mutation of HLA-B*40:02 allele is one of the possible origin of clonal escape to evade immune attack in patient with aAA.

Identification of a novel allele, HLA-A*26:01:01:03N, by full-length genome sequencing

The HLA-A*26:01:01:03N allele shows a single nucleotide difference compared with HLA-A*26:01:01:01 in intron 4(1846 G>A).

Large spin-orbit coupling and helical spin textures in 2D heterostructure [Pb2BiS3][AuTe2]

Two-dimensional heterostructures with strong spin-orbit coupling have direct relevance to topological quantum materials and potential applications in spin-orbitronics. In this work, we report on novel quantum phenomena in [Pb2BiS3][AuTe2], a new 2D strong spin-orbit coupling heterostructure system. Transport measurements reveal the spin-related carrier scattering is at odds with the Abrikosov-Gorkov model due to strong spin-orbit coupling. This is consistent with our band structure calculations which reveal a large spin-orbit coupling gap of εso = 0.21 eV. The band structure is also characterized by helical-like spin textures which are mainly induced by strong spin-orbit coupling and the inversion symmetry breaking in the heterostructure system.

Unattended Hospital and Home Sleep Apnea Testing Following Cerebrovascular Events

BACKGROUND

Home sleep apnea testing (HSAT) is an alternative to polysomnography for the detection of obstructive sleep apnea (OSA). We assessed the feasibility of HSAT as an unattended screening tool for patients with a stroke or transient ischemic attack (TIA).

AIMS

The primary outcome was the feasibility of unattended HSAT, as defined by analyzability of the data. Secondary outcomes included determining (1) predictors of obtaining nonanalyzable sleep data and (2) time to OSA detection and continuous positive airway pressure (CPAP) initiation.

METHODS

In this single-center prospective observational study, inpatients or outpatients who had sustained a stroke or TIA were screened for OSA using the ApneaLink Plus ambulatory sleep monitor in their home or hospital room.

RESULTS

There were 102 patients who completed unattended sleep monitoring. Mean age was 68.7 ± 13.7 years, 55.9% were male, 57.8% were outpatients, and 77.5% had a stroke (22.5% with TIA). Eighty-two (80.4%) patients obtained four or more hours of analyzable sleep data. Functional dependence (defined as a modified Rankin Scale of >2) and elevated body mass index were independently associated with obtaining nonanalyzable data. OSA was detected in 63.4% (52 of 82) of patients and, of those, 34 of 52 (65.4%) initiated CPAP therapy. The mean time from study recruitment to HSAT was 1.7 days (median: 1, interquartile range [IQR]: 2) and CPAP was initiated on average within 62.7 days of recruitment (median: 53, IQR: 30).

CONCLUSIONS

Unattended HSAT can be feasibly implemented after stroke or TIA. This method facilitates rapid diagnosis and management of OSA in both the outpatient and inpatient settings.

Effects of dietary mixture of garlic (Allium sativum), coriander (Coriandrum sativum) and probiotics on immune responses and caecal counts in young laying hens

This study was conducted to evaluate the effects of a combined mixture of phytogenic extracts (garlic and coriander) and probiotics on growth performance and immune responses in laying hens based on the results of in vitro studies to screen for immunomodulatory potency of each ingredient. Several parameters of immunomodulatory potency were estimated using lamina propria leucocytes (LPLs) isolated from rat intestinal mucosa tissue. Results show that the combined mixture enhanced LPLs proliferation, increased LPL-mediated cytotoxicity against YAC-1 tumour cells, and decreased lipopolysaccharide (LPS)-induced cytokine production including tumour necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in LPLs. For in vivo study, laying hens (n = 50/each diet group) were fed with control diet, a diet containing antibiotics (0.01% per kg feed) or the combined mixture (0.02% per kg feed) for 21 days. The dietary combined mixture improved egg production (p < 0.05) but not growth performance and carcass traits. Interestingly, the patterns of suppressing plasma IFN-γ productions during inflammation by LPS injection and decreasing caecal E. coli counts in the combined mixture group were comparable to those in the antibiotics group. Taken together, our results suggested that the 0.02% of combined mixture of phytogenic extracts and probiotics as ingredients has potential immunomodulatory effects in laying hens.

CLASSIFICATION OF CROPLANDS THROUGH FUSION OF OPTICAL AND SAR TIME SERIES DATA

Many satellite sensors including Landsat series have been extensively used for land cover classification. Studies have been conducted to mitigate classification problems associated with the use of single data (e.g., such as cloud contamination) through multi-sensor data fusion and the use of time series data. This study investigated two areas with different environment and climate conditions: one in South Korea and the other in US. Cropland classification was conducted by using multi-temporal Landsat 5, Radarsat-1 and digital elevation models (DEM) based on two machine learning approaches (i.e., random forest and support vector machines). Seven classification scenarios were examined and evaluated through accuracy assessment. Results show that SVM produced the best performance (overall accuracy of 93.87%) when using all temporal and spectral data as input variables. Normalized Difference Water Index (NDWI), SAR backscattering, and Normalized Difference Vegetation Index (NDVI) were identified as more contributing variables than the others for cropland classification.

Identifying obstructive sleep apnea after stroke/TIA: evaluating four simple screening tools

OBJECTIVE

Despite its high prevalence and unfavorable clinical consequences, obstructive sleep apnea (OSA) often remains underappreciated after cerebrovascular events. The purpose of our study was to evaluate the clinical utility of four simple paper-based screening tools for excluding OSA after stroke or transient ischemic attack (TIA).

PATIENTS/METHODS

Sixty-nine inpatients and outpatients with stroke or TIA during the past 180 days completed the 4-Variable screening tool (4V), STOP-BAG questionnaire (ie, STOP-BANG questionnaire without the neck circumference measurement), Berlin questionnaire, and the Sleep Obstructive apnea score optimized for Stroke (SOS). They subsequently underwent objective testing using a portable sleep monitoring device. Cutoffs were selected to maximize sensitivity and exclude OSA (AHI ≥ 10) in ≥10% of the cohort.

RESULTS

The mean age was 68.3 ± 14.2 years and 47.8% were male. Thirty-two patients (46.4%) were found to have OSA. Male sex, body mass index (BMI), and atrial fibrillation were independent predictors of OSA. Among the screening tools, the 4V had the greatest area under the curve (AUC) of 0.688 (p = 0.007); the sensitivity was 96.9% for a cutoff of <6. The STOP-BAG also significantly detected OSA with an AUC of 0.677 (p = 0.012); the sensitivity was 93.8% for a cutoff of <2. Scores on the 4V and STOP-BAG were significantly correlated with the AHI.

CONCLUSIONS

The 4V and STOP-BAG questionnaire may aid clinicians with ruling out OSA within 180 days of stroke/TIA. Due to the atypical presentation of poststroke/TIA OSA, these tools are only moderately predictive; objective testing should still be used for OSA diagnosis in this population.

Atomic and electronic structures of amorphous Ge(2)Sb(2)Te(5); melt-quenched versus ideal glasses

To investigate an amorphous structure of Ge(2)Sb(2)Te(5) that satisfies the 8-N rule (so-called 'ideal glass'), we perform alternative melt-quench simulations on Si(2)As(2)Se(5) and replace atoms in the final structure with Ge-Sb-Te. The resulting structures have salient features of the 8-N rule such as the tetrahedral configuration for all Ge atoms and the localized Te lone pairs at the valence top. In addition, the average Ge-Te and Sb-Te distances are in good agreement with experiment. The energetic stability of the ideal glass supports the existence of this amorphous structure that is distinct from the melt-quenched glass. From the analysis of electronic structures and optical dielectric constants, it is concluded that the electronic character of the melt-quenched amorphous Ge(2)Sb(2)Te(5) lies in between the resonant p-bonding of the crystalline phase and the covalent bonding of the ideal glass.

The practice of physical medicine and rehabilitation in subSaharan Africa and Antarctica: a white paper or a black mark?

AIM

The medical specialty of physical medicine and rehabilitation (PM&R) has had a proven impact on persons with disability and on healthcare systems. Documents such as The White Book on Physical and Rehabilitation Medicine in Europe have been important in defining the scope of practice within various regions. However on some continents the practice has not been well defined. The aim of this paper was to explore the practice of PM&R in subSaharan Africa and Antarctica.

METHODS

Medline searches, membership data searches, fax survey of medical schools, Internet searches, and interviews with experts.

RESULTS

The continents are dissimilar in terms of climate and government; However, both Antarctica and subSaharan Africa have no PM&R training programs, no professional organizations, no specialty board requirements, and no practicing physicians in the field. Since there are no known disabled children on Antarctica and adults are airlifted to world-class health care, the consequences of this deficit are minimal there. However the 788,000,000 permanent residents of subSaharan Africa including approximately 78 million persons with disability are left unserved.

CONCLUSIONS

Antarctica is doing fine. Africa is in a crisis. Local medical schools, hospitals doctors, and persons with disability; along with foreign volunteers, aid groups, and policymakers can impact the crisis. However government specifically national ministries of health is ultimately responsible for the health and wellbeing of citizens.

Estimation of mass transport parameters of gases for quantifying CH4 oxidation in landfill soil covers

Methane (CH(4)), which is one of the most abundant anthropogenic greenhouse gases, is produced from landfills. CH(4) is biologically oxidized to carbon dioxide, which has a lower global warming potential than methane, when it passes through a cover soil. In order to quantify the amount of CH(4) oxidized in a landfill cover soil, a soil column test, a diffusion cell test, and a mathematical model analysis were carried out. In the column test, maximum oxidation rates of CH(4) (V(max)) showed higher values in the upper part of the column than those in the lower part caused by the penetration of O(2) from the top. The organic matter content in the upper area was also higher due to the active microbial growth. The dispersion analysis results for O(2) and CH(4) in the column are counter-intuitive. As the upward flow rate of the landfill gas increased, the dispersion coefficient of CH(4) slightly increased, possibly due to the effect of mechanical dispersion. On the other hand, as the upward flow rate of the landfill gas increased, the dispersion coefficient of O(2) decreased. It is possible that the diffusion of gases in porous media is influenced by the counter-directional flow rate. Further analysis of other gases in the column, N(2) and CO(2), may be required to support this hypothesis, but in this paper we propose the possibility that the simulations using the diffusion coefficient of O(2) under the natural condition may overestimate the penetration of O(2) into the soil cover layer and consequently overestimate the oxidation of CH(4).

Linker-free directed assembly of high-performance integrated devices based on nanotubes and nanowires

Advanced electronic devices based on carbon nanotubes (NTs) and various types of nanowires (NWs) could have a role in next-generation semiconductor architectures. However, the lack of a general fabrication method has held back the development of these devices for practical applications. Here we report an assembly strategy for devices based on NTs and NWs. Inert surface molecular patterns were used to direct the adsorption and alignment of NTs and NWs on bare surfaces to form device structures without the use of linker molecules. Substrate bias further enhanced the amount of NT and NW adsorption. Significantly, as all the processing steps can be performed with conventional microfabrication facilities, our method is readily accessible to the present semiconductor industry. We use this method to demonstrate large-scale assembly of NT- and NW-based integrated devices and their applications. We also provide extensive analysis regarding the reliability of the method.

Three-day regimen of fluorouracil and cisplatin combination chemotherapy for persistence, metastatic or recurrent uterine cervical cancer

15049

Background: The five-day infusion of FP(5-fluorouracil, cisplatin) combination therapy is one of the most popular regimens for advanced cervical cancer, which has yield a 50∼60% response rate. There is some variance in the FP combination, for example, longer infusion of FP requiring longer hospitalization as well as causing more discomfort to the patients. This study was designed to assess the therapeutic effect and toxicities of three day regimen of FP combination chemotherapy instead of five day regimen for disseminated or recurrent cervical cancer. Methods: From July 1996 through April 2001, 39 patients with advanced or recurrent cervical cancer were enrolled in the study. The regimen consisted of continuous 12-hour infusion of 5-FU(5-fluorouracil) at 1000 mg/m2/day plus bolus infusion of cisplatin at 25mg/m2/day for 3 days. The treatment was repeated every 3 weeks. Results: Thirty five patients with a median age of 53 years were evaluable for response during the median follow up of 21.5 months. The response rate was 45.7% (4 CR and 12 PR), and the median duration of the overall survival was 45 months. Toxicity was acceptable with no treatment related mortality. Neutropenia in grade 3 or more was seen in 16% with 4 febrile episodes throughout a total 232 cycles. It did not appear alopecia and gastointestinal trouble in grade 3 or more. Conclusions: These results revealed that the toxicity of 3 day regimen of 5-FU and cisplatin is acceptable and the efficacy comparable to that of 5 day regimen.

No significant financial relationships to disclose.

Muscle oxygen desaturation is related to whole body VO2 during cross-country ski skating

Previous research has demonstrated that blood flow and subsequent O2 desaturation (OD) in exercising muscle is related to the static component during exercise. In speed skating, increased OD is dissociated from whole body VO2 and heart rate (HR) when the skater increases the static component by 'sitting low'. This phenomenon was evaluated in cross-country skiers by manipulating speed and incline during treadmill roller skiing. Eight male cross-country skiers (22.4 +/- 3.2 yrs old) randomly performed constant incline- and constant speed-based protocols in which increased load was manipulated in five 4min stages by treadmill incline or speed change, respectively. A strong relationship (r = 0.83) was observed between VO2 and % OD while blood volume change (deltaBV) was minimal. Unexpectedly, no HR/ VO2 or HR/OD shifts were observed between protocols. The % OD response, in relation to blood lactate values, during submaximal exercise was very similar to that of VO2. The lack of an observed greater desaturation at higher inclines suggests that the expected static load may be attenuated by an increased contribution of poling. The strong relationship of % OD to whole body VO2 may be attributed to O2 dissociation in the capillary bed of the muscle to meet aerobic energy demand and is independent of blood flow dynamics during cross-country ski skating.

Hemoglobin/myoglobin oxygen desaturation during Alpine skiing

PURPOSE

To investigate muscle blood volume (BV) change and hemoglobin/myoglobin oxygen desaturation (OD) during simulated giant slalom (GS) and slalom (SL) Alpine ski racing.

METHODS

Joint angle, BV, OD, and heart rate (HR) were evaluated during GS and SL events in 30 junior elite skiers ages 9--17 yr (13.5 +/- 2.3). Subjects were stratified by ski class and age: group I, J1 and J2, ages 15--18 yr (16.8 +/- 0.8); group II, J3, 13--14 yr (13.6 +/- 0.7); and group III, J4 and J5, 9--12 yr (11.5 +/- 1.2). Near-infrared spectrophotometry (NIRS) was used to measure BV and OD in the capillary bed of the vastus lateralis during trials. Maximal OD was determined during thigh cuff ischemia (CI). Quadriceps cross-sectional area (CSA) was estimated by skin-fold and thigh circumference.

RESULTS

Joint angles were smaller (P < 0.05) during GS than SL for ankle (83.8 +/- 11.9 degrees; 98.6 +/- 15.7 degrees ), knee (107.4 +/- 14.9 degrees; 118.3 +/- 18.0 degrees ), and hip (98.8 +/- 14.3 degrees; 107.5 +/- 16.2 degrees ). BV reduction from rest to peak exercise (Delta BV) was 30% greater (P < 0.05) during the GS than SL, whereas Delta OD was 33% greater (P < 0.05) during GS. Delta OD, relative to CI OD, was greater for all subjects during GS (79.2 +/- 3.7%) than SL (65.7 +/- 4.4%). This pattern continued within groups; group II displayed the greatest relative desaturation (82.9 +/- 7.6%). CSA was larger in older skiers (92.5 +/- 21.6; 72.5 +/- 12.3; 65.3 +/- 21.2 cm(2)) and correlated with Delta OD (P < 0.05).

CONCLUSION

The larger reduction in BV (Delta BV change) and greater OD when skiers assumed lower posture during GS than SL may be related to greater effective static load secondary to higher percent of maximal voluntary contraction and is consistent with compromised blood flow to working muscle.

Self-reported symptoms and exercise-induced asthma in the elite athlete

PURPOSE

The purpose of this study was to compare self-reported symptoms for exercise-induced asthma (EIA) to postexercise challenge pulmonary function test results in elite athletes.

METHODS

Elite athletes (N = 158; 83 men and 75 women; age: 22 +/- 4.4 yr) performed pre- and post-exercise spirometry and were grouped according to postexercise pulmonary function decrements (PFT-positive, PFT-borderline, and PFT-normal for EIA). Before the sport/environment specific exercise challenge, subjects completed an EIA symptoms-specific questionnaire.

RESULTS

Resting FEV1 values were above predicted values (114--121%) and not different between groups. Twenty-six percent of the study population demonstrated >10% postexercise drop in FEV1 and 29% reported two or more symptoms. However, the proportion of PFT-positive and PFT-normal athletes reporting two or more symptoms was not different (39% vs. 41%). Postrace cough was the most reported symptom, reported significantly more frequently for PFT-positive athletes (P < 0.05). Sensitivity/specificity analysis demonstrated a lack of effectiveness of self-reported symptoms to identify PFT-positive or exclude PFT-normal athletes. Postexercise lower limit reference ranges (MN-2SDs) were determined from normal athletes for FEV1, FEF25--75% and PEF to be -7%, -12.5%, and -18%, respectively.

CONCLUSION

Although questionnaires provide reasonable estimates of EIA prevalence among elite cold-weather athletes, the use of self-reported symptoms for EIA diagnosis in this population will likely yield high frequencies of both false positive and false negative results. Diagnosis should include spirometry using an exercise/environment specific challenge in combination with the athlete's history of asthma symptoms.

Incidence of exercise-induced bronchospasm in Olympic winter sport athletes

PURPOSE

The purpose of this project was to determine the incidence of exercise-induced bronchospasm (EIB) among U.S. Olympic winter sport athletes.

METHODS

Subjects included female and male members of the 1998 U.S. Winter Olympic Team from the following sports: biathlon, cross-country ski, figure skating, ice hockey, Nordic combined, long-track speedskating, and short-track speedskating. Assessment of EIB was conducted in conjunction with an "actual competition" (Olympic Trials, World Team Trials, World Cup Event, U.S. National Championships) or a "simulated competition" (time trial, game), which served as the exercise challenge. Standard spirometry tests were performed preexercise and at 5, 10, and 15 min postexercise. An athlete was considered EIB-positive based on a postexercise decrement in FEV1 > or = 10%.

RESULTS

For the seven sports evaluated on the 1998 U.S. Winter Olympic Team, the overall incidence of EIB across all sports and genders was 23%. The highest incidence of EIB was found in cross-country skiers, where 50% of the athletes (female = 57%; male = 43%) were diagnosed with EIB. Across the seven sports evaluated, the prevalence of EIB among the female and male athletes was 26% and 18%, respectively. Among those individuals found to be EIB-positive were athletes who won a team gold medal, one individual silver medal, and one individual bronze medal at the Nagano Winter Olympics.

CONCLUSIONS

These data suggest that: 1) EIB is prevalent in several Olympic winter sports and affects nearly one of every four elite winter sport athletes; 2) the winter sport with the highest incidence of EIB is cross-country skiing; 3) in general, EIB is more prevalent in female versus male elite winter sport athletes; and 4) athletes may compete successfully at the international level despite having EIB.