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1.
Nutr Metab Cardiovasc Dis ; 34(1): 188-197, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37798229

RÉSUMÉ

BACKGROUND AND AIMS: Retinal arteriolar narrowing and venular widening are associated with increased cardiovascular risk, even at young ages. Whether diet contributes to early microvascular changes in children is not widely explored. We explored the associations of frequency of healthy and unhealthy food group intake with retinal vessel calibers in black and white children. METHODS AND RESULTS: This study included school-aged (5-9 years) black (N = 433, 7.46 ± 0.98 years), and white (N = 403, 7.43 ± 0.82 years) children. Anthropometric and blood pressure measurements were taken, along with retinal vessel calibers (central retinal arteriolar (CRAE) and venular (CRVE) equivalents). Frequencies of food group intake were assessed using a food-frequency questionnaire. A factor analysis was performed to describe food group patters. Independent associations between retinal vessel calibers and frequencies of food group intake and food group patters were explored. In black children, cookies, cakes, and biscuits were associated with narrower arterioles (p < 0.05). In white children, cold sweetened beverages were associated with narrower arterioles (p = 0.02), whereas salty snacks were associated with narrower arterioles (p = 0.01) and wider venules (p < 0.05). Fruits were positively associated with CRAE (p = 0.03) in white children only. CONCLUSION: A higher frequency of unhealthy food group consumption was associated with retinal arteriolar narrowing and venular widening in both black and white children. However, fruit intake was shown beneficial for retinal microvascular health in white children only. Our findings may highlight the importance of promoting healthy eating patterns from early childhood which may reduce the risk of premature cardiovascular disease development.


Sujet(s)
Maladies cardiovasculaires , Vaisseaux rétiniens , Enfant , Humains , Enfant d'âge préscolaire , Adolescent , République d'Afrique du Sud/épidémiologie , Régime alimentaire , Artérioles , Consommation alimentaire , Veinules
2.
Int J Hosp Manag ; 114: 103550, 2023 Sep.
Article de Anglais | MEDLINE | ID: mdl-37388274

RÉSUMÉ

Airbnb was able to recover faster than hotels from the downturn caused by the COVID-19 pandemic. This research note examines whether Airbnb's success resulted from tourists feeling safer in Airbnbs due to their greater opportunities for social distancing. Nearly 9500 U.S. adults were surveyed between March 2020 and July 2021, and asked the degree to which they would be concerned about staying in a hotel or Airbnb, within the context of the pandemic. Very similar levels of concern were associated with both lodging types, even as this concern decreased as the pandemic unfolded. The similar levels of concern towards hotels and Airbnbs suggest that other factors better explain Airbnb's comparatively rapid recovery from the pandemic. Implications and suggestions for future research are discussed.

3.
BMJ Open ; 13(5): e068932, 2023 05 05.
Article de Anglais | MEDLINE | ID: mdl-37147093

RÉSUMÉ

OBJECTIVES: Assess the impact of single rooms versus multioccupancy accommodation on inpatient healthcare outcomes and processes. DESIGN: Systematic review and narrative synthesis. DATA SOURCES: Medline, Embase, Google Scholar and the National Institute for Health and Care Excellence website up to 17 February 2022. ELIGIBILITY CRITERIA: Eligible papers assessed the effect on inpatients staying in hospital of being assigned to a either a single room or shared accommodation, except where that assignment was for a direct clinical reason like preventing infection spread. DATA EXTRACTION AND SYNTHESIS: Data were extracted and synthesised narratively, according to the methods of Campbell et al. RESULTS: Of 4861 citations initially identified, 145 were judged to be relevant to this review. Five main method types were reported. All studies had methodological issues that potentially biased the results by not adjusting for confounding factors that are likely to have contributed to the outcomes. Ninety-two papers compared clinical outcomes for patients in single rooms versus shared accommodation. No clearly consistent conclusions could be drawn about overall benefits of single rooms. Single rooms were most likely to be associated with a small overall clinical benefit for the most severely ill patients, especially neonates in intensive care. Patients who preferred single rooms tended to do so for privacy and for reduced disturbances. By contrast, some groups were more likely to prefer shared accommodation to avoid loneliness. Greater costs associated with building single rooms were small and likely to be recouped over time by other efficiencies. CONCLUSIONS: The lack of difference between inpatient accommodation types in a large number of studies suggests that there would be little effect on clinical outcomes, particularly in routine care. Patients in intensive care areas are most likely to benefit from single rooms. Most patients preferred single rooms for privacy and some preferred shared accommodation for avoiding loneliness. PROSPERO REGISTRATION NUMBER: CRD42022311689.


Sujet(s)
Hospitalisation , Sécurité des patients , Nouveau-né , Humains , Hôpitaux , Patients hospitalisés , Solitude
4.
BMC Cardiovasc Disord ; 22(1): 403, 2022 09 09.
Article de Anglais | MEDLINE | ID: mdl-36085014

RÉSUMÉ

BACKGROUND: Left ventricular hypertrophy (LVH) is a marker of increased risk in developing future life-threatening cardiovascular disease (CVD), however, it is unclear how CVD risk factors, such as obesity, blood pressure (BP), and tobacco use, are associated with left ventricular (LV) remodeling and LVH in urban African populations. Therefore, we aimed to identify the prevalence of LVH as well as the health factors associated with LV remodeling and LVH, within black South African adult women and their pre-pubescent children. METHODS: Black female adults (n = 123; age: 29-68 years) and their children (n = 64; age: 4-10; 55% female) were recruited from the Birth to Twenty Plus Cohort in Soweto, South Africa. Tobacco and alcohol use, physical activity, presence of diabetes mellitus, heart disease, and medication were self-reported. Height, weight, and blood pressure were measured in triplicate to determine the prevalence of obesity and hypertension respectively. Echocardiography was used to assess LV mass at end-diastole, based on linear measurements, and indexed to body surface area to determine LVH. RESULTS: Hypertension and obesity prevalences were 35.8% and 59.3% for adults and 45.3% and 6.3% for children. Self-reported tobacco use in adults was 22.8%. LVH prevalence was 35.8% in adults (75% eccentric: 25% concentric), and 6.3% in children. Concentric remodeling was observed in 15.4% of adults, however, concentric remodeling was only found in one child. In adults, obesity [OR: 2.54 (1.07-6.02; p = 0.02)] and hypertension [3.39 (1.08-10.62; p = 0.04)] significantly increased the odds of LVH, specifically eccentric LVH, while concentric LVH was associated with self-reported tobacco use [OR: 4.58 (1.18-17.73; p = 0.03)]. Although no logistic regression was run within children, of the four children LVH, three had elevated blood pressure and the child with normal blood pressure was overweight. CONCLUSIONS: The association between obesity, hypertension, tobacco use, and LVH in adults, and the 6% prevalence of LVH in children, calls for stronger public health efforts to control risk factors and monitor children who are at risk.


Sujet(s)
Hypertension artérielle , Remodelage ventriculaire , Adulte , Sujet âgé , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Hypertension artérielle/complications , Hypertension artérielle/diagnostic , Hypertension artérielle/épidémiologie , Hypertrophie ventriculaire gauche/imagerie diagnostique , Hypertrophie ventriculaire gauche/épidémiologie , Hypertrophie ventriculaire gauche/étiologie , Mâle , Adulte d'âge moyen , Obésité , République d'Afrique du Sud/épidémiologie , Usage de tabac , Remodelage ventriculaire/physiologie
5.
BMJ Open ; 12(9): e059910, 2022 09 23.
Article de Anglais | MEDLINE | ID: mdl-36153021

RÉSUMÉ

OBJECTIVES: Cardiovascular disease is increasing in many low and middle-income countries, including those in Africa. To inform strategies for the prevention of cardiovascular disease in South Africa, we sought to determine the broad heritability of phenotypic markers of cardiovascular risk across three generations. DESIGN: A cross-sectional study conducted in a longitudinal family cohort. SETTING: Research unit within a tertiary hospital in a historically disadvantaged, large urban township of South Africa. PARTICIPANTS: 195 individuals from 65 biological families with all three generations including third-generation children aged 4-10 years were recruited from the longest running intergenerational cohort study in Africa, the Birth to Twenty Plus cohort. All adults (grandparents and parents) were female while children were male or female. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was heritability of blood pressure (BP; brachial and central pressures). Secondary outcomes were heritability of arterial stiffness (pulse wave velocity), carotid intima media thickness (cIMT) and left ventricular mass indexed to body surface area (LVMI). RESULTS: While no significant intergenerational relationships of BP or arterial stiffness were found, there were significant relationships in LVMI across all three generations (p<0.04), and in cIMT between grandparents and parents (p=0.0166). Heritability, the proportion of phenotypic trait variation attributable to genetics, was estimated from three common statistical methods and ranged from 23% to 44% for cIMT and from 21% to 39% for LVMI. CONCLUSIONS: Structural indicators of vascular health, which are strong markers of future clinical cardiovascular outcomes, transmit between generations within African families. Identification of these markers in parents may be useful to trigger assessments of preventable risk factors for cardiovascular disease in offspring.


Sujet(s)
Maladies cardiovasculaires , Hypertension artérielle , Rigidité vasculaire , Adulte , Pression sanguine/génétique , Artère brachiale , Maladies cardiovasculaires/complications , Maladies cardiovasculaires/épidémiologie , Maladies cardiovasculaires/génétique , Épaisseur intima-média carotidienne , Enfant , Enfant d'âge préscolaire , Études de cohortes , Études transversales , Femelle , Humains , Mâle , Analyse de l'onde de pouls , Facteurs de risque , République d'Afrique du Sud/épidémiologie
6.
Heart Lung Circ ; 31(10): 1376-1384, 2022 Oct.
Article de Anglais | MEDLINE | ID: mdl-35868966

RÉSUMÉ

OBJECTIVE: Identifying individuals at increased risk of early vascular ageing (EVA) is paramount to inform intervention and prevention strategies and curb the increasing burden of cardiovascular disease. METHODS: We stratified and phenotyped pre-screened young apparently healthy South African adults (20-30 yrs) (n=1,041) into vascular ageing profile groups based on carotid femoral pulse wave velocity (cfPWV) percentiles (healthy vascular ageing [HVA]; average vascular ageing [AVA] and EVA). We further compared various anthropometric, cardiovascular (CV), oxidative stress and lifestyle risk factors and determined factor scores to explore associations between CV measures and factor clusters to explore associations in those at risk of EVA. RESULTS: Young adults in the EVA group displayed marked phenotypic characteristics in terms of anthropometry, CV, and lifestyle risk factors, even though cfPWV were within healthy ranges. Blood pressure (brachial and central) and cfPWV were all incrementally higher across all three vascular ageing groups (p-trend ≤0.011). Hypertension, lifestyle risk factors such as self-reported smoking and alcohol consumption were all highest in the EVA group (p-trend ≤0.046). Additionally, in the EVA group only, cfPWV (adj. R2=0.028; ß=0.171; p=0.042) associated positively with Factor 2 (oxidative stress and antioxidant capacity). No associations existed between Factor 1 (basic lipids) and any anthropometric or CV measures (p>0.050). CONCLUSION: Young adults with higher cfPWV presented with a less favourable vascular profile and more unhealthy lifestyle behaviours compared to groups with lower cfPWV. In the EVA group, cfPWV positively associated with a cluster of oxidative stress and antioxidant capacity. Early lifestyle behaviours may have the ability to modify the balance between oxidants and antioxidants, potentially contributing to early onset arterial stiffness.


Sujet(s)
Analyse de l'onde de pouls , Rigidité vasculaire , Vieillissement , Antioxydants , Pression sanguine/physiologie , Humains , Lipides , Oxydants , Facteurs de risque , Rigidité vasculaire/physiologie , Jeune adulte
8.
Atherosclerosis ; 350: 51-57, 2022 06.
Article de Anglais | MEDLINE | ID: mdl-35490596

RÉSUMÉ

BACKGROUND AND AIMS: Childhood obesity and high blood pressure (BP) are main determinants for cardiovascular disease development with regional and ethnic differences. Narrower arteriolar (CRAE) and wider venular (CRVE) retinal vessel diameters are sensitive markers of early vascular compromise in children. We aimed to compare retinal vessel diameters and investigate associations and odds ratios with body mass index (BMI) and BP in a multi-national/ethnic childhood study. METHODS: BMI, systolic (SBP) and diastolic BP (DBP) were screened in 929 black and white South African (SA) and 1171 Swiss children (aged 5-9 years). Retinal assessments were performed using a retinal vessel analyzer to determine CRAE and CRVE. RESULTS: Black SA children had wider CRVE compared to white SA and Swiss children (all p < 0.001). However, BMI or BP was not associated with CRVE in black SA children. Higher BMI and BP associated with narrower CRAE in all children, except for BMI in black SA children, in whom narrower CRAE was found for every unit increase in SBP (ß = -0.199 µm, p = 0.001) and DBP (ß = -0.312 µm, p < 0.001). Obesity (OR:1.38[1.01; 1.89]), hypertension (OR:1.90[1.53; 2.36]) and black ethnicity (OR:1.50[1.18; 1.92]) increased the likelihood for arteriolar narrowing. CONCLUSIONS: Black SA children presented with wider retinal venules compared to their white SA and Swiss peers, which was unexplained by conventional risk factors. The overall risk of arteriolar narrowing was driven by obesity, hypertension and ethnicity. Our findings indicate the importance to differentiate cardiovascular risk by microvascular phenotype in different populations and ethnicity early in life.


Sujet(s)
Hypertension artérielle , Obésité pédiatrique , Pression sanguine/physiologie , Enfant , Enfant d'âge préscolaire , Ethnies , Humains , Hypertension artérielle/diagnostic , Hypertension artérielle/épidémiologie , Obésité pédiatrique/diagnostic , Obésité pédiatrique/épidémiologie , Phénotype , Vaisseaux rétiniens
9.
J Hypertens ; 40(1): 65-75, 2022 01 01.
Article de Anglais | MEDLINE | ID: mdl-34285149

RÉSUMÉ

BACKGROUND: Carotid-femoral pulse wave velocity (PWV) is the gold-standard noninvasive measure of arterial stiffness. Data comparing tonometry-based devices such as the SphygmoCor XCEL to simpler brachial-cuff-based estimates of PWV, such as from the Mobil-O-Graph in African populations are sparse. We therefore aimed to compare PWV measured by the Mobil-O-Graph and the SphygmoCor XCEL device in a sample of South African women and children. METHODS: Women (n = 85) 29 years [interquartile range (IQR): 29-69] and their children/grandchildren (n = 27) 7 years (IQR: 4-11) were recruited for PWV measurement with Mobil-O-Graph and SphygmoCor XCEL on the same day. Wilcoxon signed-rank test, regression analysis, spearman correlation and Bland-Altman plots were used for PWV comparison between devices. RESULTS: For adults, the SphygmoCor XCEL device had a significantly higher PWV (7.3 m/s, IQR: 6.4-8.5) compared with the Mobil-O-Graph (5.9 m/s, IQR: 5.0-8.1, P = 0.001) with a correlation coefficient of 0.809 (P ≤ 0.001). Bland--Altman analysis indicated an acceptable level of agreement but significant bias (mean difference PWV: 0.90 ±â€Š1.02 m/s; limits of agreement: -1.10 to 2.90). The odds of having a PWV difference more than 1 m/s decreased with a higher age [odds ratio (OR): 0.95, 95% confidence interval (95% CI) = 0.92-0.98] and increased with greater height (OR: 1.10, 95% CI = 1.01-1.21, P = 0.03) in multivariable analysis. In children, the Bland-Altman indicated an excellent level of agreement (-0.03 ±â€Š0.63 m/s; limits of agreement: -1.26 to 1.21), but no correlation was found (rs = 0.08, P = 0.71). CONCLUSION: Particularly in younger and taller women, the Mobil-O-Graph significantly underestimated PWV compared with the SphygmoCor. Although no correlation was found between the two devices for children, further research is required due to the small sample size. Furthermore, the clinical value of both methods in young African populations requires further investigation.


Sujet(s)
Analyse de l'onde de pouls , Rigidité vasculaire , Adulte , Pression sanguine , Artère brachiale , Vitesse de l'onde de pouls carotido-fémorale , Enfant , Femelle , Humains
10.
J Hypertens ; 40(1): 136-142, 2022 01 01.
Article de Anglais | MEDLINE | ID: mdl-34857706

RÉSUMÉ

OBJECTIVES AND METHODS: Hypertension is a growing health concern in childhood populations and individuals of African descent. As the kidneys play a significant role in blood pressure regulation, we compared alpha-1 microglobulin (A1M) as a marker of proximal tubular function between young healthy black and white children (n = 957; aged: 5-9 years) and explored its association with blood pressure. RESULTS: The black children had higher levels of A1M (P < 0.001) and higher DBP (P < 0.001) when compared with their white counterparts. In multiple regression analysis, SBP (adj. R2 = 0.173, ß = 0.151; P < 0.001) and DBP (adj. R2 = 0.110, ß = 0.179; P < 0.001) associated positively with A1M in the black children. In binary logistic regression, each standard deviation increase in A1M increased the odds of having elevated blood pressure by 28% (P = 0.002) in the black group, independent of age, sex, BMI z-score and body height. No significance was reached in the white children. CONCLUSION: Our findings highlight the importance of a marker of proximal tubular function, especially in children of black ethnicity, in the setting of elevated blood pressure. Early childhood screening for elevated blood pressure remains essential in order to promote primary prevention of hypertension and early onset kidney damage in children.


Sujet(s)
Hypertension artérielle , Adolescent , , Pression sanguine , Taille , Enfant , Enfant d'âge préscolaire , Ethnies , Humains
11.
BMJ Open ; 11(12): e052455, 2021 12 20.
Article de Anglais | MEDLINE | ID: mdl-34930736

RÉSUMÉ

OBJECTIVES: Assess whether impactibility modelling is being used to refine risk stratification for preventive health interventions. DESIGN: Systematic review. SETTING: Primary and secondary healthcare populations. PAPERS: Articles published from 2010 to 2020 on the use or implementation of impactibility modelling in population health management, reported with the terms 'intervenability', 'amenability', and 'propensity to succeed' (PTS) and associated with the themes 'care sensitivity', 'characteristic responders', 'needs gap', 'case finding', 'patient selection' and 'risk stratification'. INTERVENTIONS: Qualitative synthesis to identify themes for approaches to impactibility modelling. RESULTS: Of 1244 records identified, 20 were eligible for inclusion. Identified themes were 'health conditions amenable to care' (n=6), 'PTS modelling' (n=8) and 'comparison or combination with clinical judgement' (n=6). For the theme 'health conditions amenable to care', changes in practice did not reduce admissions, particularly for ambulatory care sensitive conditions, and sometimes increased them, with implementation noted as a possible issue. For 'PTS modelling', high costs and needs did not necessarily equate to high impactibility and targeting a larger number of individuals with disorders associated with lower costs had more potential. PTS modelling seemed to improve accuracy in care planning, estimation of cost savings, engagement and/or care quality. The 'comparison or combination with clinical judgement' theme suggested that models can reach reasonable to good discriminatory power to detect impactable patients. For instance, a model used to identify patients appropriate for proactive multimorbid care management showed good concordance with physicians (c-statistic 0.75). Another model employing electronic health record scores reached 65% concordance with nurse and physician decisions when referring elderly hospitalised patients to a readmission prevention programme. However, healthcare professionals consider much wider information that might improve or impede the likelihood of treatment impact, suggesting that complementary use of models might be optimum. CONCLUSIONS: The efficiency and equity of targeted preventive care guided by risk stratification could be augmented and personalised by impactibility modelling.


Sujet(s)
Gestion de la santé de la population , Santé de la population , Sujet âgé , Hospitalisation , Humains , Services de médecine préventive , Qualité des soins de santé
12.
J Hypertens ; 39(11): 2190-2199, 2021 11 01.
Article de Anglais | MEDLINE | ID: mdl-34620809

RÉSUMÉ

BACKGROUND: Obesity and hypertension prevalence among children are a concern, with limited evidence available on sex and ethnic differences in childhood blood pressure. We aimed to determine the number of children with hypertension and obesity to identify unique adiposity and blood pressure characteristics by sex and ethnicity, and to estimate the odds of having elevated blood pressure with increasing adiposity. METHODS: We included 1062 healthy children (5-9 years of age) in an observational school-based study in South Africa. Pediatric validated automated devices were used to measure brachial blood pressure and performed pulse wave analysis to assess central hemodynamics. Standard anthropometry was carried out to determine body composition and demographic questionnaires were completed. RESULTS: Almost 20% of children were overweight/obese and 14.1% had elevated blood pressure or hypertension (22.8%). Ethnic differences included greater adiposity in white compared with black children (all P < 0.0001), but higher DBP and total vascular resistance in black compared with white children (both P < 0.05). DBP and total vascular resistance were also higher in girls than boys (both P < 0.01). A 51-60% increased risk of developing elevated blood pressure was observed for 1SD (standard deviation) increase of sex-specific BMI [1.60 (1.4-1.8); P < 0.0001] and waist/height ratio [1.51 (1.3-1.7); P < 0.0001]. CONCLUSION: Unique sex and ethnic differences in body composition and blood pressure exist in prepubescent children, with overweight/obesity increasing the risk of elevated blood pressure. Our findings support primary prevention strategies to combat the growing burden of hypertension and obesity-related diseases in youth. TRIAL REGISTRATION: The study is registered on ClinicalTrials.gov (NCT04056377).


Sujet(s)
Hypertension artérielle , Adolescent , Pression sanguine , Indice de masse corporelle , Enfant , Études transversales , Femelle , Humains , Hypertension artérielle/épidémiologie , Mâle , Obésité/épidémiologie , Prévalence , Facteurs de risque , République d'Afrique du Sud/épidémiologie
13.
Front Sports Act Living ; 3: 702922, 2021.
Article de Anglais | MEDLINE | ID: mdl-34458726

RÉSUMÉ

We currently find ourselves living in precarious times, with old and new social inequities on the rise due to the challenges associated with an unprecedented rise of global migration and neoliberalism, amplified in our post COVID-19 world. Research has demonstrated that there is a high correlation between inequality at the societal level and the overall health and wellbeing of individuals within those societies. We believe that school health and physical education (HPE) has a significant role to play in addressing and acting on social inequities that impact on the wellbeing of both students and society as a whole. Based on the findings of an international research project called EDUHEALTH which explored pedagogies for social justice in school health and physical education (HPE) across Sweden, Norway and New Zealand, this paper aims to highlight the addressing of (in)equality and student wellbeing through HPE practice. In particular, the paper presents nine different but complementary pedagogies for social justice that we believe can improve individual, collective, and societal wellbeing. We conclude by proposing that, if adopted across a whole school curriculum, these nine pedagogies for social justice could form the basis of a holistic school-wide community approach aimed at improving both student and societal wellbeing.

14.
Afr J Emerg Med ; 11(3): 372-377, 2021 Sep.
Article de Anglais | MEDLINE | ID: mdl-34367899

RÉSUMÉ

A changing climate will have demonstrable effects on health and healthcare systems, with specific and disproportionate effects on communities in Africa. Emergency care systems and providers have an opportunity to be at the forefront of efforts to combat the worst health effects from climate change. The 2020 African Conference on Emergency Medicine, under the auspices of the African Federation for Emergency Medicine, convened its first ever workshop on the topic of climate change and human health. Structured as a full day virtual course, the didactic sections were available for both live and asynchronous learning with more than 100 participants enrolled in the course. The workshop introduced the topic of the health effects of climate as they relate to emergency care in Africa and provided a forum to discuss ideas regarding the way forward. Lectures and focused discussions addressed three broad themes related to: health impacts, health care delivery, and advocacy. To our knowledge, this is the first workshop for health professionals to cover topics specific to emergency care, climate change, and health in Africa. The results of this workshop will help to guide future efforts aimed at advancing emergency care approaches in Africa with regard to medical education, research, and policy. AFRICAN RELEVANCE: •Climate-related extreme weather events are adversely affecting health and health care delivery in African countries.•African organisations, cities, and nations have taken positive steps to adapt and build climate resilience.•There are opportunities for emergency care professionals and scholars to continue to expand, and lead, climate and health education, research, and policy initiatives on the continent.

15.
United European Gastroenterol J ; 9(7): 809-818, 2021 09.
Article de Anglais | MEDLINE | ID: mdl-34431615

RÉSUMÉ

BACKGROUND & AIMS: Nitric oxide, a major inhibitory nonadrenergic, noncholinergic neurotransmitter that relaxes smooth muscle, may be implicated in the pathophysiology of visceral hypersensitivity in irritable bowel syndrome (IBS). Impaired bioavailability of the nitric oxide precursor molecule L-arginine and higher concentrations of methylarginines (endogenous inhibitors of nitric oxide synthesis) are known to impair nitric oxide synthesis in numerous gastrointestinal cell types. We therefore examined serum concentrations of L-arginine and the methylarginines in a nested case-control study, to assess whether these factors are associated with adult IBS. METHODS: Data on clinical characteristics, methylarginines, and L-arginine (measured using LC-MS/MS) were collected from a random population-based cohort of Australian adults (median age = 64 years; IQR = 60-70). Cases of IBS, defined according to Rome III criteria (N = 156), and controls (N = 332) were identified from within the cohort at the 5-year follow-up. RESULTS: In adjusted logistic regression analyses, L-arginine, asymmetric dimethylarginine, symmetric dimethylarginine, L-arginine/asymmetric dimethylarginine ratio, and Kessler-10 psychological distress scores were significantly associated with IBS (p < 0.05). [Correction added on 18 September 2021, after first online publication: In the preceding sentence, the value (p > 0.05) has been changed to (p < 0.05)]. Similar results were found for IBS subtypes. Higher serum L-arginine concentration had the strongest association with IBS diagnosis, with an odds ratio of 9.03 for those with serum L-arginine at the 75th (84 µmol/L) versus 25th (46 µmol/L) percentile (95% CI: 5.99-13.62). L-arginine had the best discriminative ability with a bias-adjusted area under the receiver operator characteristic curve of 0.859. CONCLUSIONS: Higher serum concentrations of L-arginine and endogenous methylarginines are strongly associated with IBS in adults.


Sujet(s)
Arginine/analogues et dérivés , Arginine/sang , Syndrome du côlon irritable/sang , Monoxyde d'azote/biosynthèse , Sujet âgé , Sujet âgé de 80 ans ou plus , Marqueurs biologiques/sang , Études cas-témoins , Études de cohortes , Femelle , Humains , Syndrome du côlon irritable/diagnostic , Syndrome du côlon irritable/psychologie , Modèles logistiques , Mâle , Adulte d'âge moyen , Odds ratio , Détresse psychologique , Courbe ROC
17.
Microvasc Res ; 137: 104180, 2021 09.
Article de Anglais | MEDLINE | ID: mdl-34015274

RÉSUMÉ

AIMS: Plasminogen activator inhibitor-1 (PAI-1), traditionally associated with fibrinolysis, is increasingly implicated in impaired vascular function. However, studies on its association with microvascular function are limited to the cutaneous and coronary microvascular beds in older and diseased individuals. To better understand its potential involvement in the early stages of disease development, we investigated the associations of retinal vasodilatory responses to flicker light with PAI-1 activity (PAI-1act) in young and healthy individuals. METHODS: We included healthy Black and White women and men (n = 518; aged 20-30 years), and measured plasma PAI-1act and retinal vasodilatory responses to flicker light provocation. We also collected demographic and lifestyle data, measured blood pressure, anthropometry, blood lipids, inflammatory and other biomarkers. RESULTS: In multivariate regression analyses, maximal retinal venular dilation associated independently and inversely with PAI-1act (adj. R2 = 0.11; ß = -0.15; p = 0.001) in the total group. In exploratory subgroup analyses, this association remained in White women (adj. R2 = 0.07; ß = -0.23; p = 0.005), and was more robust with younger age and lower blood pressure and in non-smokers, but also with greater central adiposity, higher low-density lipoprotein cholesterol and inflammation (all p < 0.05). CONCLUSIONS: Our data suggest that in young individuals, PAI-1 may already be associated with subclinical microvascular dysfunction.


Sujet(s)
Inhibiteur-1 d'activateur du plasminogène/sang , Vaisseaux rétiniens/physiologie , Vasodilatation , Veinules/physiologie , Adulte , Facteurs âges , Marqueurs biologiques/sang , Maladies cardiovasculaires/sang , Maladies cardiovasculaires/diagnostic , Maladies cardiovasculaires/physiopathologie , Études transversales , Femelle , Volontaires sains , Humains , Lumière , Mâle , Stimulation lumineuse , Valeur prédictive des tests , Facteurs de risque , République d'Afrique du Sud , Jeune adulte
18.
Microcirculation ; 28(6): e12714, 2021 08.
Article de Anglais | MEDLINE | ID: mdl-34008905

RÉSUMÉ

OBJECTIVE: Lifestyle risk factors vary between socioeconomic status (SES) groups and may influence cardiovascular function differently. The retinal microvasculature allows for monitoring early changes in cardiovascular health, and therefore, we investigated whether retinal vessel calibers associate differently with modifiable risk factors in different SES groups. METHODS: We included 1064 young adults (aged 20-30 years) grouped by low and high SES. The central retinal artery and vein equivalents (CRAE, CRVE) were determined from fundus images captured using the Dynamic Retinal Vessel Analyzer (Imedos Systems GmbH, Jena, Germany). We collected anthropometry, self-reported alcohol consumption, and biochemical data. RESULTS: Retinal vessel calibers did not differ between SES groups (p ≥ .80) after adjusting for sex and ethnicity. Unique independent associations were observed in the low SES group, where CRAE (ß = 0.08, p = .042) and CRVE (ß = .14, p = .001) associated positively with cotinine and body mass index, respectively. In the high SES group, CRAE (ß = -0.09, p = .027) associated negatively with alcohol consumption. CONCLUSION: At young ages, retinal vessel calibers associated differently with modifiable lifestyle risk factors within each SES group. Our data highlight the importance of detecting adverse lifestyle risk factors among young adults from diverse socioeconomic settings to improve prevention of cardiovascular disease.


Sujet(s)
Artère centrale de la rétine , Vaisseaux rétiniens , Adulte , Humains , Mode de vie , Facteurs de risque , Facteurs socioéconomiques , Jeune adulte
19.
Pharmaceutics ; 13(3)2021 Feb 27.
Article de Anglais | MEDLINE | ID: mdl-33673552

RÉSUMÉ

Raman spectroscopy has proven valuable for determining the composition of manufactured drug products, as well as identifying counterfeit drugs. Here we present a simple method to determine the active pharmaceutical ingredient (API) mass percent in a sample that does not require knowledge of the identities or relative mass percents of the inactive pharmaceutical ingredients (excipients). And further, we demonstrated the ability of the method to pass or fail a manufactured drug product batch based on a calculated acceptance value in accordance with the US Pharmacopeia method for content uniformity. The method was developed by fitting the Raman spectra of 30 Claritin® tablets with weighted percentages of the Raman spectrum of its API, loratadine, and a composite spectrum of the known excipients. The mean loratadine mass of 9.79 ± 40 mg per 100 mg tablet compared favorably to the 10.21 ± 0.63 mg per 100 mg tablet determined using high-performance liquid chromatography, both of which met the acceptance value to pass the 10 mg API product as labelled. The method was then applied to a generic version of the Claritin product that employed different excipients of unknown mass percents. A Raman spectrum representative of all excipients was created by subtracting the API Raman spectrum from the product spectrum. The Raman spectra of the 30 generic tablets were then fit with weighted percents of the pure loratadine spectrum and the created excipient spectrum, and used to determine a mean API mass for the tablets of 10.12 ± 40 mg, again meeting the acceptance value for the 10 mg API product. The data suggest that this simple method could be used to pass or fail manufactured drug product batches in accordance with the US Pharmacopeia method for content uniformity, without knowledge of the excipients.

20.
Nutr Metab Cardiovasc Dis ; 31(4): 1071-1080, 2021 04 09.
Article de Anglais | MEDLINE | ID: mdl-33549447

RÉSUMÉ

BACKGROUND AND AIMS: Heart rate variability (HRV) is a main determinant of autonomic function and related to the development of hypertension and cardiovascular (CV) disease. Hypertension develops in black populations at an earlier age, which could be due to differences in the autonomic nervous system activity and sodium/potassium handling in black and white populations. We investigated whether HRV is associated with 24 h urinary sodium and potassium excretion and blood pressure (BP) in a young bi-ethnic cohort. METHODS AND RESULTS: We examined 423 black and 483 white healthy adults (aged 24.5 ± 3.1 years) for 24 h HRV, including standard deviation of normal RR intervals (SDNN) reflecting autonomic variations over time, and root mean square of successive differences (RMSSD) reflecting parasympathetic activity. We measured 24 h urinary sodium and potassium concentration and BP. The black group had lower SDNN and potassium excretion as well as higher RMSSD, sodium and Na/k ratio compared to the white group (all p < 0.05). Only in black individuals, urinary potassium excretion was independently and negatively associated with SDNN (ß[95% CI];-0.26[-0.50;-0.02]ms) and RMSSD (-0.14[-0.27;-0.01]ms, p < 0.05). One unit increase in sodium/potassium (Na/K) ratio was associated with higher SDNN (ß[95% CI]; 3.04[0.89; 5.19]ms) and RMSSD (1.60[0.41; 2.78]ms) in the black cohort only (both p < 0.001). In both groups elevated 24 h diastolic BP was associated with lower RMSSD (p < 0.05). CONCLUSION: Lower potassium excretion and higher Na/K ratio related independently to higher HRV in young and healthy black adults. A better ethnic-specific understanding of sodium and potassium handling is required as part of preventive cardiology, especially in black individuals. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03292094; URL: https://clinicaltrials.gov/ct2/show/NCT03292094.


Sujet(s)
, Pression sanguine , Disparités de l'état de santé , Rythme cardiaque , Hypertension artérielle/ethnologie , Potassium/urine , Élimination rénale , , Adulte , Facteurs âges , Système nerveux autonome/physiopathologie , Études transversales , Femelle , Volontaires sains , Humains , Hypertension artérielle/physiopathologie , Hypertension artérielle/urine , Mâle , Natriurèse , Études prospectives , Appréciation des risques , Facteurs de risque , Sodium/urine , République d'Afrique du Sud/épidémiologie , Jeune adulte
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