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1.
Artigo em Espanhol | PAHO-IRIS | ID: phr-52467

RESUMO

[RESUMEN]. La hipertensión arterial es una causa modificable muy prevalente de enfermedades cardiovasculares, accidentes cerebrovasculares y muerte. Medir con exactitud la presión arterial es fundamental, dado que un error de medición de 5 mmHg puede ser motivo para clasificar incorrectamente como hipertensas a 84 millones de personas en todo el mundo. En la presente declaración de posición se resumen los procedimientos para optimizar el desempeño del observador al medir la presión arterial en el consultorio, con atención especial a los entornos de ingresos bajos o medianos, donde esta medición se ve complicada por limitaciones de recursos y tiempo, sobrecarga de trabajo y falta de suministro eléctrico. Es posible reducir al mínimo muchos errores de medición con una preparación adecuada de los pacientes y el uso de técnicas estandarizadas. Para simplificar la medición y prevenir errores del observador, deben usarse tensiómetros semiautomáticos o automáticos de manguito validados, en lugar del método por auscultación. Pueden ayudar también la distribución de tareas, la creación de un área específica de medición y el uso de aparatos semiautomáticos o de carga solar. Es fundamental garantizar la capacitación inicial y periódica de los integrantes del equipo de salud. Debe considerarse la implementación de programas de certificación de bajo costo y fácilmente accesibles con el objetivo de mejorar la medición de la presión arterial.


[ABSTRACT]. High blood pressure (BP) is a highly prevalent modifiable cause of cardiovascular disease, stroke, and death. Accurate BP measurement is critical, given that a 5-mmHg measurement error may lead to incorrect hypertension status classification in 84 million individuals worldwide. This position statement summarizes procedures for optimizing observer performance in clinic BP measurement, with special attention given to low-to-middle-income settings, where resource limitations, heavy workloads, time constraints, and lack of electrical power make measurement more challenging. Many measurement errors can be minimized by appropriate patient preparation and standardized techniques. Validated semi-automated/automated upper arm cuff devices should be used instead of auscultation to simplify measurement and prevent observer error. Task sharing, creating a dedicated measurement workstation, and using semi-automated or solar-charged devices may help. Ensuring observer training, and periodic re-training, is critical. Low-cost, easily accessible certification programs should be considered to facilitate best BP measurement practice.


[RESUMO]. A hipertensão é uma causa altamente prevalente de doença cardiovascular, acidente vascular cerebral e morte. A medição precisa da pressão arterial (PA) é um aspecto crítico, uma vez que erros de mensuração da ordem de 5 mmHg podem levar a uma classificação incorreta do status de hipertensão em 84 milhões de pessoas em todo o mundo. O presente posicionamento resume os procedimentos para otimizar o desempenho do observador (o indivíduo responsável pela mensuração da PA) na mensuração clínica da PA, com atenção especial para contextos de baixa a média renda, onde recursos limitados, cargas de trabalho pesadas, restrições de tempo e falta de energia elétrica tornam mais desafiadora a tarefa de medir a PA. Muitos erros de mensuração podem ser minimizados pela preparação adequada do paciente e pelo uso de técnicas padronizadas. Para simplificar a mensuração e evitar erros do observador, devem-se utilizar dispositivos semiautomatizados ou automatizados validados, com manguito para braço, ao invés de auscultação. O compartilhamento de tarefas, a criação de uma estação de trabalho dedicada à mensuração e o uso de dispositivos semiautomatizados ou com carga solar podem ajudar. É essencial que seja assegurado o treinamento e retreinamento periódico do observador. Programas de certificação de baixo custo e de fácil acesso devem ser considerados para facilitar a adoção das melhores práticas na mensuração da PA.


Assuntos
Pressão Arterial , Equipamentos de Medição , Consenso , Saúde Global , Hipertensão , Oscilometria , Pressão Arterial , Equipamentos de Medição , Consenso , Saúde Global , Hipertensão , Oscilometria , Pressão Arterial , Equipamentos de Medição , Saúde Global , Hipertensão , Oscilometria
2.
Obes Surg ; 30(10): 3776-3783, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32495072

RESUMO

PURPOSE: Obesity clearly increases cardiovascular risk, often inducing high blood pressure (BP), impaired left ventricular (LV) function, and increased arterial stiffness. Intensive weight loss and bariatric surgery induce improvement in hypertension and diabetes for morbid obesity. Carotid artery haemodynamics is a powerful prognostic indicator for stroke and cognitive decline independent of BP. The aim of this study was to evaluate the impact of a 3-stage bariatric strategy of diet, bariatric surgery, and consequent weight loss on carotid haemodynamics and cardiac diastolic function. MATERIAL AND METHODS: This prospective study included 26 patients (45 ± 10 years, 4 men) with severe obesity undergoing bariatric surgery without comorbidities (hypertension, diabetes, etc.). Anthropometry, BP, Doppler echocardiography, and common carotid haemodynamics by ultrasound were measured at three times: (1) baseline, (2) after 1-month diet (post-diet), and (3) 8 months after surgery (post-surgery). The lnDU-loop method was used to estimate local carotid pulse wave velocity (ncPWV). RESULTS: Baseline BMI was 47.9 ± 7.1 kg/m2 and reduced by 5% and 30% post-diet and post-surgery, respectively. BP decreased only post-diet, without pulse pressure change. However, ncPWV, 6.27 ± 1.35 m/s at baseline, was significantly reduced by 10% and 23% post-diet and post-surgery, respectively, also adjusted for BP changes. The E/A ratio rose from 0.95 ± 0.20 to 1.27 ± 0.31 (p < 0.005), without change in LV geometry or mass, while heart rate and cardiac output fell substantially. CONCLUSION: Weight loss following diet and bariatric surgery is associated with reduced carotid arterial stiffness and improved LV diastolic function. Diet and bariatric surgery are effective treatments for morbid obesity with its concomitant adverse cardiovascular effects.

3.
BMC Public Health ; 20(1): 712, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32423390

RESUMO

BACKGROUND: To evaluate the association between weight misperception and psychological symptoms in the Determinants of young Adults Social well-being and Health (DASH) longitudinal study. METHODS: A longitudinal sample of 3227 adolescents, in 49 secondary schools in London, aged 11-16 years participated in 2002/2003 and were followed up in 2005/2006. A sub-sample (N = 595) was followed up again at ages 21-23 years in 2012/2013. An index of weight misperception was derived from weight perception and measured weight. Psychological well- being was measured using the Strengths and Difficulties Questionnaire at 11-16 years and the General Health Questionnaire at 21-23 years. Associations with weight misperception was assessed using regression models, adjusted for socio-economic and lifestyle factors. RESULTS: White British males and females were more likely than ethnic minority peers to report accurate perceptions of measured weight. At 11-13y, 46% females and 38% males did not have an accurate perception of their measured weight. The comparable figures at 14-16y were 42 and 40%. Compared with male adolescents, more females perceived themselves as overweight or were unsure of their weight but measured normal weight, and this was more pronounced among Indians, Pakistanis and Bangladeshis. At 14-16y, more males perceived themselves as underweight but measured normal weight, and this was more pronounced among Indians. Compared with those who had an accurate perception of their normal weight, a higher likelihood of probable clinically-relevant psychological symptoms was observed among those who measured normal weight but perceived themselves to be underweight (females Odds Ratio (OR) = 1.87 95% CI 1.03-3.40; males OR = 2.34 95% CI 1.47-3.71), overweight (females only OR = 2.06 95% CI 1.10-3.87), or unsure of their weight (males only OR = 1.61 95% CI 1.04-2.49). Among females, the association was driven by internalising rather than externalising symptoms. An accurate perception of overweight was associated with higher psychological symptoms in adolescence and early 20s. Ethnic specific effects were not evident. CONCLUSION: Weight misperception may be an important determinant of psychological symptoms in young people, with an accurate perception of normal weight status being protective. Culturally targeted interventions should be considered to promote healthy perceptions of body image.

4.
Arterioscler Thromb Vasc Biol ; 40(5): 1044-1054, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32237903

RESUMO

Early vascular aging reflects increased arterial stiffness of central blood vessels at young chronological ages and powerfully predicts cardiovascular events and mortality, independent of routine brachial blood pressure and other risk factors. Since ethnic disparities exist in routine blood pressure, in hypertension and cardiovascular outcomes, this review evaluates major studies comparing arterial stiffness through the life course between different ethnic groups or races (which have no biological definition)-in children, adolescents, young, and middle-aged adults and the very elderly. Most report that compared with white European-origin samples, populations of black African descent have increased central arterial stiffness throughout different life stages, as well as a more rapid increase in arterial stiffness at young ages. Exceptions may include African Caribbean origin people in Europe. Differences in vascular structure and function are clearest, where obesity, socioeconomic, and psychosocial factors are most marked. Few studies evaluate a wider spectrum of ethnic groups or factors contributing to these ethnic disparities. Genetic effects are not obvious; maternal risk and intergenerational studies are scarce. Nevertheless, across all ethnic groups, for given levels of blood pressure and age, some people have stiffer central arteries than others. These individuals are most at risk of vascular events and mortality and, therefore, may benefit from early, as yet untested, preventive action and treatment.


Assuntos
Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/fisiopatologia , Grupos de Populações Continentais , Disparidades nos Níveis de Saúde , Rigidez Vascular , Adolescente , Adulto , Fatores Etários , Idoso , Envelhecimento/etnologia , Doenças Cardiovasculares/diagnóstico , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Raciais , Medição de Risco , Fatores de Risco , Fatores Sexuais , Determinantes Sociais da Saúde/etnologia , Adulto Jovem
5.
Prostate Cancer Prostatic Dis ; 23(3): 527-533, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32123316

RESUMO

BACKGROUND: Spironolactone, a cheap effective diuretic used to manage hypertension and heart failure, also has anti-androgenic effects through its non-selective binding to steroid receptors, and hence may affect prostate cancer (PCa) risk. This study investigated the association between spironolactone use and PCa risk. For comparison, we also examined associations with thiazide diuretics which do not have anti-androgenic properties. METHODS: A matched case-control study was undertaken using population-wide data from the Prostate Cancer Data Base Sweden (PCBaSe). All PCa cases diagnosed from 2014 to 2016 were matched by birth year and county with PCa-free controls selected from the general population (1:5). Multivariable conditional logistic regression was used to examine associations between spironolactone use (dose and duration) and PCa risk, and similarly for thiazides. RESULTS: Three percent of the 31,591 cases and 4% of the 156,802 controls had been prescribed spironolactone. Multivariable analyses indicated reduced risk of PCa among those ever exposed to spironolactone (odds ratio [OR] 0.83; 95% confidence interval [CI]: 0.76-0.89), with a stronger association for current users (OR: 0.77, 95% CI: 0.69-0.86) than past users (OR: 0.88; 95% CI: 0.79-0.97) and decreasing risk with increasing dose (p-trend < 0.001). No association was observed for thiazide exposure and PCa risk. Biases due to differences in prescribing patterns or frequency of PSA testing may have influenced these findings. CONCLUSION: PCa risk was reduced among men exposed to the diuretic spironolactone. Further investigation of spironolactone's potential chemopreventive effects is warranted.

6.
J Hypertens ; 38(7): 1278-1285, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32205559

RESUMO

OBJECTIVES: Hypertension phenotypes differ between Africans and Europeans, with a greater prevalence of low renin salt-sensitive hypertension and greater predisposition to adverse cardiac remodelling in Africans. To elucidate the roles of inheritance and environment in determining hypertension phenotypes in sub-Saharan Africans and white-Europeans, we compared phenotypes in white individuals in the UK (n = 132) and in African individuals in the UK (n = 158) and Nigeria (n = 179). METHODS: Biochemistry, blood pressure, left ventricular structure (echocardiography) and 24-h urinary collections of sodium and potassium were measured. RESULTS: Twenty-four-hour urinary sodium/potassium ratio was lower in individuals living in Europe (both African and white: 2.32 ±â€Š0.15 and 2.28 ±â€Š0.17) than in individuals in Nigeria (4.09 ±â€Š0.26, both P < 0.001) reflecting proportionately higher potassium intake in Europeans (African or white) than African residents. Plasma renin was lower in Africans irrespective of residency than white Europeans, but aldosterone was higher in Africans in Europe than those in Africa (466.15 ±â€Š32.95 vs. 258.60 ±â€Š17.42 pmol/l, P < 0.001). Left ventricular mass index adjusted for blood pressure and other confounders was greatest in Africans in Europe (103.27 ±â€Š2.32 g/m) compared with those in Africa (89.28 ±â€Š1.98 g/m) or white Europeans (86.77 ±â€Š2.63 g/m, both P < 0.001). CONCLUSION: Despite a similar low renin state in African origin individuals living in Europe and Africa, a higher aldosterone level, possibly related to higher potassium intake or other environmental factors, may contribute to greater cardiac remodelling in Africans in Europe.

7.
Diabetologia ; 63(2): 313-323, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31732790

RESUMO

AIMS/HYPOTHESIS: Progressive decline in functional beta cell mass is central to the development of type 2 diabetes. Elevated serum levels of extracellular nicotinamide phosphoribosyltransferase (eNAMPT) are associated with beta cell failure in type 2 diabetes and eNAMPT immuno-neutralisation improves glucose tolerance in mouse models of diabetes. Despite this, the effects of eNAMPT on functional beta cell mass are poorly elucidated, with some studies having separately reported beta cell-protective effects of eNAMPT. eNAMPT exists in structurally and functionally distinct monomeric and dimeric forms. Dimerisation is essential for the NAD-biosynthetic capacity of NAMPT. Monomeric eNAMPT does not possess NAD-biosynthetic capacity and may exert distinct NAD-independent effects. This study aimed to fully characterise the structure-functional effects of eNAMPT on pancreatic beta cell functional mass and to relate these to beta cell failure in type 2 diabetes. METHODS: CD-1 mice and serum from obese humans who were without diabetes, with impaired fasting glucose (IFG) or with type 2 diabetes (from the Body Fat, Surgery and Hormone [BodyFatS&H] study) or with or at risk of developing type 2 diabetes (from the VaSera trial) were used in this study. We generated recombinant wild-type and monomeric eNAMPT to explore the effects of eNAMPT on functional beta cell mass in isolated mouse and human islets. Beta cell function was determined by static and dynamic insulin secretion and intracellular calcium microfluorimetry. NAD-biosynthetic capacity of eNAMPT was assessed by colorimetric and fluorescent assays and by native mass spectrometry. Islet cell number was determined by immunohistochemical staining for insulin, glucagon and somatostatin, with islet apoptosis determined by caspase 3/7 activity. Markers of inflammation and beta cell identity were determined by quantitative reverse transcription PCR. Total, monomeric and dimeric eNAMPT and nicotinamide mononucleotide (NMN) were evaluated by ELISA, western blot and fluorometric assay using serum from non-diabetic, glucose intolerant and type 2 diabetic individuals. RESULTS: eNAMPT exerts bimodal and concentration- and structure-functional-dependent effects on beta cell functional mass. At low physiological concentrations (~1 ng/ml), as seen in serum from humans without diabetes, eNAMPT enhances beta cell function through NAD-dependent mechanisms, consistent with eNAMPT being present as a dimer. However, as eNAMPT concentrations rise to ~5 ng/ml, as in type 2 diabetes, eNAMPT begins to adopt a monomeric form and mediates beta cell dysfunction, reduced beta cell identity and number, increased alpha cell number and increased apoptosis, through NAD-independent proinflammatory mechanisms. CONCLUSIONS/INTERPRETATION: We have characterised a novel mechanism of beta cell dysfunction in type 2 diabetes. At low physiological levels, eNAMPT exists in dimer form and maintains beta cell function and identity through NAD-dependent mechanisms. However, as eNAMPT levels rise, as in type 2 diabetes, structure-functional changes occur resulting in marked elevation of monomeric eNAMPT, which induces a diabetic phenotype in pancreatic islets. Strategies to selectively target monomeric eNAMPT could represent promising therapeutic strategies for the treatment of type 2 diabetes.

8.
Br J Clin Pharmacol ; 86(5): 891-902, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31833569

RESUMO

AIMS: To test if spironolactone or dietary nitrate from beetroot juice could reduce arterial stiffness as aortic pulse wave velocity (PWVart), a potential treatment target, independently of blood pressure. METHODS: Daily spironolactone (≤50 mg) vs doxazosin (control ≤16 mg) and 70 mL beetroot juice (Beet-It ≤11 mmol nitrate) vs nitrate-depleted juice (placebo; 0 mmol nitrate) were tested in people at risk or with type-2 diabetes using a double-blind, 6-month factorial trial. Vascular indices (baseline, 12, 24 weeks) were cardiac-ankle vascular index (CAVI), a nominally pressure-independent stiffness measure (primary outcome), PWVart secondary, central systolic pressure and augmentation. Analysis was intention-to-treat, adjusted for systolic pressure differences between trial arms. RESULTS: Spironolactone did not reduce stiffness, with evidence for reduced CAVI on doxazosin rather than spironolactone (mean difference [95% confidence interval]; 0.25 [-0.3, 0.5] units, P = .080), firmer for PWVart (0.37 [0.01, 0.7] m/s, P = .045). There was no difference in systolic pressure reduction between spironolactone and doxazosin (0.7 [-4.8, 3.3] mmHg, P = .7). Circulating nitrate and nitrite increased on active vs placebo juice, with central systolic pressure lowered -2.6 [-4.5, - 0.8] mmHg, P = .007 more on the active juice, but did not reduce CAVI, PWVart or peripheral pressure. Change in nitrate and nitrite concentrations were 1.5-fold [1.1-2.2] and 2.2-fold [1.3, 3.6] higher on spironolactone than on doxazosin respectively; both P < .05. CONCLUSION: Contrary to our hypothesis, in at-risk/type 2 diabetes patients, spironolactone did not reduce arterial stiffness, rather PWVart was lower on doxazosin. Dietary nitrate elevated plasma nitrite, selectively lowering central systolic pressure, observed previously for nitrite.

9.
J Invest Dermatol ; 140(7): 1418-1426.e1, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31883961

RESUMO

Epidemiology suggests that melanin inhibits cutaneous vitamin D3 synthesis by UVR. Laboratory investigations assessing the impact of melanin on vitamin D production have produced contradictory results. We determined the effect of melanin on vitamin D3 photosynthesis in healthy young volunteers (n = 102) of Fitzpatrick skin types II-VI (white to black). Participants, irrespective of skin type, were exposed to the same suberythemal UVR dose, to 85% body surface area, using solar simulated UVR or narrowband UVB (311 nm). This was repeated five times with intervals of 3-4 days between UVR exposures. Blood was taken before, during, and after the irradiation and assessed for serum 25-hydroxyvitamin D3 (25[OH]D3) as a marker of vitamin D3 status. Linear UVR dose-dependent increases in 25(OH)D3 were highly significant (P ≤ 7.7 x 10-11). The ratios of regression slopes of the different skin type groups were compared, and only skin type II was significantly steeper than the other groups. Comparisons between extreme skin types II and VI showed melanin inhibition factors of approximately 1.3-1.4, depending on the UVR source. We conclude that the inhibitory effect of melanin on vitamin D3 synthesis is small, compared with erythema, but that this difference may be sufficient to explain the epidemiological data.

10.
J Hypertens ; 37(9): 1737-1745, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31034450

RESUMO

: High blood pressure (BP) is a highly prevalent modifiable cause of cardiovascular disease, stroke, and death. Accurate BP measurement is critical, given that a 5-mmHg measurement error may lead to incorrect hypertension status classification in 84 million individuals worldwide. This position statement summarizes procedures for optimizing observer performance in clinic BP measurement, with special attention given to low-to-middle-income settings, where resource limitations, heavy workloads, time constraints, and lack of electrical power make measurement more challenging. Many measurement errors can be minimized by appropriate patient preparation and standardized techniques. Validated semi-automated/automated upper arm cuff devices should be used instead of auscultation to simplify measurement and prevent observer error. Task sharing, creating a dedicated measurement workstation, and using semi-automated or solar-charged devices may help. Ensuring observer training, and periodic re-training, is critical. Low-cost, easily accessible certification programs should be considered to facilitate best BP measurement practice.

13.
J Am Heart Assoc ; 8(6): e011771, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30879408

RESUMO

Background Malaria exposure in childhood may contribute to high blood pressure ( BP ) in adults. We used sickle cell trait ( SCT ) and α+thalassemia, genetic variants conferring partial protection against malaria, as tools to test this hypothesis. Methods and Results Study sites were Kilifi, Kenya, which has malaria transmission, and Nairobi, Kenya, and Jackson, Mississippi, where there is no malaria transmission. The primary outcome was 24-hour systolic BP. Prevalent hypertension, diagnosed using European Society of Hypertension thresholds was a secondary outcome. We performed regression analyses adjusting for age, sex, and estimated glomerular filtration rate. We studied 1127 participants in Kilifi, 516 in Nairobi, and 651 in Jackson. SCT frequency was 21% in Kilifi, 16% in Nairobi, and 9% in Jackson. SCT was associated with -2.4 (95% CI , -4.7 to -0.2) mm Hg lower 24-hour systolic BP in Kilifi but had no effect in Nairobi/Jackson. The effect of SCT in Kilifi was limited to 30- to 59-year-old participants, among whom it was associated with -6.1 mm Hg ( CI , -10.5 to -1.8) lower 24-hour systolic BP. In pooled analysis allowing interaction by site, the effect of SCT on 24-hour systolic BP in Kilifi was -3.5 mm Hg ( CI , -6.9 to -0.1), increasing to -5.2 mm Hg ( CI , -9.5 to -0.9) when replacing estimated glomerular filtration rate with urine albumin to creatinine ratio as a covariate. In Kilifi, the prevalence ratio for hypertension was 0.86 ( CI , 0.76-0.98) for SCT and 0.89 ( CI , 0.80-0.99) for α+thalassemia. Conclusions Lifelong malaria protection is associated with lower BP in Kilifi. Confirmation of this finding at other sites and elucidating the mechanisms involved may yield new preventive and therapeutic targets.

14.
Int J Behav Nutr Phys Act ; 16(1): 19, 2019 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-30736801

RESUMO

BACKGROUND: Evidence on the relationship between fruit and vegetable consumption (FV) and mental health in adolescence is sparse and inconsistent. Social determinants of FV include ethnicity, family environments and economic disadvantage. We investigated the relationship between FV and mental health in the British multi-ethnic Determinants of Adolescents (now young Adult) Social well-being and Health (DASH) longitudinal study. METHODS: A longitudinal study of 4683 adolescents living in London at age 11-13 years and followed up at 14-16 years. FV was measured using validated questions on the number of portions consumed daily. Mental health was measured by the Strengths and Difficulties Questionnaire as mean Total Difficulties Score (TDS) and by classification as a 'probable clinical case' (TDS > 17). Social measures included ethnicity, parenting and socioeconomic circumstances. Multilevel modelling was used to investigate the association between FV and mental health throughout adolescence. RESULTS: Low FV was common among adolescents, with approximately 60-70% of adolescents reporting < 5 portions/day and 20-30% reporting < 1 portion/day. In late adolescence, most ethnic minority groups reported lower FV than their White peers. In fully adjusted models, < 1 portion/day remained a significant correlate with mean TDS (Coef: 0.55, 0.29-0.81, P < 0.001) and TDS > 17 (Odds Ratio: 1.43, 1.11-1.85, P = 0.007). Gender- or ethnic-specific effects were not observed. Low parental care partly attenuated the association between FV and mental health. CONCLUSIONS: Low FV is a longitudinal correlate of poor mental health across adolescence. A focus on FV in parenting interventions could yield interrelated benefits across developmental outcomes given its importance to both physical and socioemotional health.


Assuntos
Comportamento do Adolescente , Adolescente , Dieta , Comportamento Alimentar , Frutas , Saúde Mental , Pais , Verduras , Comportamento do Adolescente/etnologia , Criança , Estudos de Coortes , Dieta/etnologia , Dieta/normas , Inquéritos sobre Dietas , Grupos Étnicos/estatística & dados numéricos , Feminino , Humanos , Estudos Longitudinais , Masculino , Transtornos Mentais/etnologia , Saúde Mental/etnologia , Grupos Minoritários , Razão de Chances , Poder Familiar , Fatores Socioeconômicos , Reino Unido , População Urbana
15.
Br J Clin Pharmacol ; 85(1): 169-180, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30294825

RESUMO

AIMS: The aims of the present study were to explore whether a long-term intervention with dietary nitrate [(NO3 - ), a potential tolerance-free source of beneficial vasoactive nitric oxide] and spironolactone (to oppose aldosterone's potential deleterious cardiovascular effects) improve cardiac structure/function, independently of blood pressure (BP), in patients with/at risk of type 2 diabetes (a population at risk of heart failure). METHODS: A subsample of participants in our double-blind, randomized, factorial-design intervention (VaSera) trial of active beetroot juice as a nitrate source (≤11.2 mmol) or placebo (nitrate depleted) beetroot juice, and either ≤50 mg spironolactone or ≤16 mg doxazosin (control), had transthoracic cardiac ultrasounds at baseline (n = 105), and at 3 months and 6 months (n = 87) after the start of the intervention. Analysis was by modified intent-to-treat. RESULTS: Nitrate-containing juice (n = 40) decreased left ventricular (LV) end-diastolic volume {-6.3 [95% confidence interval (CI) -11.1, -1.6] ml} and end-systolic volume [-3.2 (95% CI -5.9, -0.5) ml], and increased end-diastolic mass/volume ratio [+0.04 (95% CI 0.00, 0.07)], relative to placebo juice (n = 47). Spironolactone (n = 44) reduced relative wall thickness compared with doxazosin (n = 43) [-0.01 (95% CI -0.02, -0.00)]. Although spironolactone reduced LV mass index relative to baseline [-1.48 (95% CI -2.08, -0.88) g m-2.7 ], there was no difference vs. doxazosin [-0.85 (95% CI -1.76, 0.05) g m-2.7 ]. Spironolactone also decreased the E/A ratio [-0.12 (95% CI -0.19, -0.04)] and increased S' (a tissue-Doppler systolic function index) by 0.52 (95% CI 0.05, 1.0) cm s-1 . BP did not differ between the juices, or between the drugs. CONCLUSIONS: Six months' dietary nitrate decreased LV volumes ~5%, representing new, sustained, BP-independent benefits on cardiac structure, extending mechanisms characterized in preclinical models of heart failure. Spironolactone's effects on cardiac remodelling and systolic-diastolic function, although confirmatory, were independent of BP.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Insuficiência Cardíaca/prevenção & controle , Coração/efeitos dos fármacos , Nitratos/administração & dosagem , Espironolactona/administração & dosagem , Adulto , Idoso , Beta vulgaris/química , Pressão Sanguínea/efeitos dos fármacos , Método Duplo-Cego , Doxazossina/administração & dosagem , Ecocardiografia , Feminino , Sucos de Frutas e Vegetais , Coração/diagnóstico por imagem , Insuficiência Cardíaca/etiologia , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Análise de Onda de Pulso , Resultado do Tratamento , Rigidez Vascular/efeitos dos fármacos
16.
Proc Nutr Soc ; 77(4): 456-469, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30260313

RESUMO

Childhood obesity is a common concern across global cities and threatens sustainable urban development. Initiatives to improve nutrition and encourage physical exercise are promising but are yet to exert significant influence on prevention. Childhood obesity in London is associated with distinct ethnic and socio-economic patterns. Ethnic inequalities in health-related behaviour endure, underpinned by inequalities in employment, housing, access to welfare services, and discrimination. Addressing these growing concerns requires a clearer understanding of the socio-cultural, environmental and economic contexts of urban living that promote obesity. We explore opportunities for prevention using asset based-approaches to nutritional health and well-being, with a particular focus on adolescents from diverse ethnic backgrounds living in London. We focus on the important role that community engagement and multi-sectoral partnership play in improving the nutritional outcomes of London's children. London's children and adolescents grow up in the rich cultural mix of a global city where local streets are characterised by diversity in ethnicities, languages, religions, foods, and customs, creating complex and fluid identities. Growing up with such everyday diversity we argue can enhance the quality of life for London's children and strengthen their social capital. The Determinants of young Adult Social well-being and Health longitudinal study of about 6500 of London's young people demonstrated the positive impact of cultural diversity. Born to parents from over a hundred countries and exposed to multi-lingual households and religious practices, they demonstrated strong psychological resilience and sense of pride from cultural straddling, despite material disadvantage and discrimination. Supporting the potential contribution of such socio-cultural assets is in keeping with the values of social justice and equitable and sustainable development. Our work signals the importance of community engagement and multisectoral partnerships, involving, for example, schools and faith-based organisations, to improve the nutrition of London's children.


Assuntos
Diversidade Cultural , Dieta , Grupos Étnicos , Comportamentos Relacionados com a Saúde , Estado Nutricional , Obesidade Pediátrica/prevenção & controle , População Urbana , Adolescente , Adulto , Criança , Cidades , Cultura , Humanos , Londres , Qualidade de Vida , Resiliência Psicológica , Discriminação Social , Fatores Socioeconômicos , Adulto Jovem
17.
Lancet Diabetes Endocrinol ; 6(6): 464-475, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29655877

RESUMO

BACKGROUND: In the PATHWAY-2 study of resistant hypertension, spironolactone reduced blood pressure substantially more than conventional antihypertensive drugs. We did three substudies to assess the mechanisms underlying this superiority and the pathogenesis of resistant hypertension. METHODS: PATHWAY-2 was a randomised, double-blind crossover trial done at 14 UK primary and secondary care sites in 314 patients with resistant hypertension. Patients were given 12 weeks of once daily treatment with each of placebo, spironolactone 25-50 mg, bisoprolol 5-10 mg, and doxazosin 4-8 mg and the change in home systolic blood pressure was assessed as the primary outcome. In our three substudies, we assessed plasma aldosterone, renin, and aldosterone-to-renin ratio (ARR) as predictors of home systolic blood pressure, and estimated prevalence of primary aldosteronism (substudy 1); assessed the effects of each drug in terms of thoracic fluid index, cardiac index, stroke index, and systemic vascular resistance at seven sites with haemodynamic monitoring facilities (substudy 2); and assessed the effect of amiloride 10-20 mg once daily on clinic systolic blood pressure during an optional 6-12 week open-label runout phase (substudy 3). The PATHWAY-2 trial is registered with EudraCT, number 2008-007149-30, and ClinicalTrials.gov, number NCT02369081. FINDINGS: Of the 314 patients in PATHWAY-2, 269 participated in one or more of the three substudies: 126 in substudy 1, 226 in substudy 2, and 146 in substudy 3. Home systolic blood pressure reduction by spironolactone was predicted by ARR (r2=0·13, p<0·0001) and plasma renin (r2=0·11, p=0·00024). 42 patients had low renin concentrations (predefined as the lowest tertile of plasma renin), of which 31 had a plasma aldosterone concentration greater than the mean value for all 126 patients (250 pmol/L). Thus, 31 (25% [95% CI 17-33]) of 126 patients were deemed to have inappropriately high aldosterone concentrations. Thoracic fluid content was reduced by 6·8% from baseline (95% CI 4·0 to 8·8; p<0·0001) with spironolactone, but not other treatments. Amiloride (10 mg once daily) reduced clinic systolic blood pressure by 20·4 mm Hg (95% CI 18·3-22·5), compared with a reduction of 18·3 mm Hg (16·2-20·5) with spironolactone (25 mg once daily). No serious adverse events were recorded, and adverse symptoms were not systematically recorded after the end of the double-blind treatment. Mean plasma potassium concentrations increased from 4·02 mmol/L (95% CI 3·95-4·08) on placebo to 4·50 (4·44-4·57) on amiloride (p<0·0001). INTERPRETATION: Our results suggest that resistant hypertension is commonly a salt-retaining state, most likely due to inappropriate aldosterone secretion. Mineralocorticoid receptor blockade by spironolactone overcomes the salt retention and resistance of hypertension to treatment. Amiloride seems to be as effective an antihypertensive as spironolactone, offering a substitute treatment for resistant hypertension. FUNDING: British Heart Foundation and UK National Institute for Health Research.


Assuntos
Anti-Hipertensivos/uso terapêutico , Bisoprolol/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Doxazossina/uso terapêutico , Hipertensão/tratamento farmacológico , Espironolactona/uso terapêutico , Aldosterona/metabolismo , Amilorida/uso terapêutico , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
PLoS One ; 13(1): e0190496, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29364959

RESUMO

INTRODUCTION: Studies, predominantly from the US, suggest that positive parenting, social support, academic achievement, and ethnic identity may buffer the impact of racism on health behaviours, including smoking, but little is known about how such effects might operate for ethnically diverse young people in the United Kingdom. We use the Determinants of young Adult Social well-being and Health (DASH), the largest UK longitudinal study of ethnically diverse young people, to address the following questions: a) Is racism associated with smoking? b) Does the relationship between racism and smoking vary by gender and by ethnicity? (c) Do religious involvement, parenting style and relationship with parents modify any observed relationship? and d) What are the qualitative experiences of racism and how might family or religion buffer the impact? METHODS: The cohort was recruited from 51 London schools. 6643 were seen at 11-13y and 4785 seen again at 14-16y. 665 participated in pilot follow-up at 21-23y, 42 in qualitative interviews. Self-report questionnaires included lifestyles, socio-economic and psychosocial factors. Mixed-effect models examined the associations between racism and smoking. RESULTS: Smoking prevalence increased from adolescence to age 21-23y, although ethnic minorities remained less likely to smoke. Racism was an independent longitudinal correlate of ever smoking throughout adolescence (odds ratio 1.77, 95% Confidence Interval 1.45-2.17) and from early adolescence to early 20s (1.90, 95% CI 1.25-2.90). Smoking initiation in late adolescence was associated with cumulative exposure to racism (1.77, 95% CI 1.23-2.54). Parent-child relationships and place of worship attendance were independent longitudinal correlates that were protective of smoking. Qualitative narratives explored how parenting, religion and cultural identity buffered the adverse impact of racism. CONCLUSIONS: Racism was associated with smoking behaviour from early adolescence to early adulthood, regardless of gender, ethnicity or socio-economic circumstances adding to evidence of the need to consider racism as an important social determinant of health across the life course.


Assuntos
Fumar Cigarros , Racismo , Adolescente , Feminino , Humanos , Estudos Longitudinais , Masculino , Fatores Socioeconômicos , Reino Unido , Adulto Jovem
19.
Am J Epidemiol ; 187(2): 199-205, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28992220

RESUMO

The potential association between sickle cell trait (SCT) and increased arterial stiffness/blood pressure (BP) has not been evaluated in detail despite its association with stroke, sudden death, and renal disease. We performed 24-hour ambulatory BP monitoring and arterial stiffness measurements in adolescents raised in a malaria-free environment in Kenya. Between December 2015 and June 2016, 938 randomly selected adolescents (ages 11-17 years) who had been continuous residents of Nairobi from birth were invited to participate in the study. Standard clinic BP measurement was performed, followed by 24-hour ambulatory BP monitoring and arterial stiffness measurement using an Arteriograph24 (TensioMed Ltd., Budapest, Hungary) device. SCT status was determined using DNA genotyping in contemporaneously collected blood samples. Of the 938 adolescents invited to participate, 609 (65%) provided complete data for analysis. SCT was present in 103 (15%). Mean 24-hour systolic and diastolic BPs were 116 (standard deviation (SD), 11.5) mm Hg and 64 (SD, 7) mm Hg, respectively, in children with SCT and 117 (SD, 11.4) mm Hg and 64 (SD, 6.8) mm Hg, respectively, in non-SCT children. Mean pulse wave velocity (PWV) was 7.1 (SD, 0.8) m/second and 7.0 (SD, 0.8) m/second in SCT and non-SCT children, respectively. We observed no differences in PWV or in any clinic or ambulatory BP-derived measures between adolescents with and without SCT. These data suggest that SCT does not independently influence BP or PWV.


Assuntos
Pressão Sanguínea/genética , Traço Falciforme/genética , Traço Falciforme/fisiopatologia , Rigidez Vascular/genética , Adolescente , Monitorização Ambulatorial da Pressão Arterial , Criança , Feminino , Técnicas de Genotipagem , Humanos , Quênia , Masculino , Análise de Onda de Pulso/estatística & dados numéricos
20.
Front Physiol ; 8: 949, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29213245

RESUMO

Background: The metabolic syndrome (MetS) and aging are associated with modifications in blood coagulation factors, vascular inflammation, and increased risk of thrombosis. Objectives: Our aim was to determine concomitant changes in thrombin generation in the blood compartment and at the surface of vascular smooth muscle cells (VSMCs) and its interplay with adipokines, free fatty acids (FFA), and metalloproteinases (MMPs) in obese Zucker rats that share features of the human MetS. Methods: Obese and age-matched lean Zucker rats were compared at 25 and 80 weeks of age. Thrombin generation was assessed by calibrated automated thrombography (CAT). Results: Endogenous thrombin potential (ETP) was increased in obese rats independent of platelets and age. Clot half-lysis time was delayed with obesity and age. Interleukin (IL)-1ß and IL-13 were increased with obesity and age respectively. Addition of exogenous fibrinogen, leptin, linoleic, or palmitic acid increased thrombin generation in plasma whereas adiponectin had an opposite effect. ETP was increased at the surface of VSMCs from obese rats and addition of exogenous palmitic acid further enhanced ETP values. Gelatinase activity was increased in aorta at both ages in obese rats and MMP-2 activity was increased in VSMCs from obese rats. Conclusions: Our study demonstrated in MetS an early prothrombotic phenotype of the blood compartment reinforced by procoagulant properties of dedifferentiated and inflammatory VSMCs. Mechanisms involved (1) increased fibrinogen and impaired fibrinolysis and (2) increased saturated fatty acids responsible for additive procoagulant effects. Whether specifically targeting this hypercoagulability using direct thrombin inhibitors would improve outcome in MetS is worth investigating.

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