RESUMEN
BACKGROUND: In the context of increased asthma exacerbations associated with climatic changes such as thunderstorm asthma, interest in establishing the link between pollen exposure and asthma hospital admissions has intensified. Here, we systematically reviewed and performed a meta-analysis of studies on pollen and emergency department (ED) attendance. METHODS: A search for studies with appropriate search strategy in MEDLINE, EMBASE, Web of Science and CINAHL was conducted. Each study was assessed for quality and risk of bias. The available evidence was summarized both qualitatively and meta-analysed using random-effects models when moderate heterogeneity was observed. RESULTS: Fourteen studies were included. The pollen taxa investigated differed between studies, allowing meta-analysis only of the effect of grass pollen. A statistically significant increase in the percentage change in the mean number of asthma ED presentations (MPC) (pooled results from 3 studies) was observed for an increase in 10 grass pollen grains per cubic metre of exposure 1.88% (95% CI = 0.94%, 2.82%). Time series studies showed positive correlations between pollen concentrations and ED presentations. Age-stratified studies found strongest associations in children aged 5-17 years old. CONCLUSION: Exposure to ambient grass pollen is an important trigger for childhood asthma exacerbations requiring ED attendance. As pollen exposure is increasingly a problem especially in relation to thunderstorm asthma, studies with uniform measures of pollen and similar analytical methods are necessary to fully understand its impact on human health.
Asunto(s)
Alérgenos/análisis , Asma/inmunología , Servicio de Urgencia en Hospital , Polen/inmunología , Adolescente , Niño , Preescolar , Cambio Climático , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Malezas/efectos adversos , Malezas/inmunología , Poaceae/efectos adversos , Poaceae/inmunología , Tracheophyta/efectos adversos , Tracheophyta/inmunología , Árboles/efectos adversos , Árboles/inmunologíaRESUMEN
Consistent, strong predictors of obesity treatment outcomes have not been identified. It has been suggested that broadening the range of predictor variables examined may be valuable. We explored methods to predict outcomes of a very-low-energy diet (VLED)-based programme in a clinically comparable setting, using a wide array of pre-intervention biological and psychosocial participant data. A total of 61 women and 39 men (mean ± standard deviation [SD] body mass index: 39.8 ± 7.3 kg/m2 ) underwent an 8-week VLED and 12-month follow-up. At baseline, participants underwent a blood test and assessment of psychological, social and behavioural factors previously associated with treatment outcomes. Logistic regression, linear discriminant analysis, decision trees and random forests were used to model outcomes from baseline variables. Of the 100 participants, 88 completed the VLED and 42 attended the Week 60 visit. Overall prediction rates for weight loss of ≥10% at weeks 8 and 60, and attrition at Week 60, using combined data were between 77.8 and 87.6% for logistic regression, and lower for other methods. When logistic regression analyses included only baseline demographic and anthropometric variables, prediction rates were 76.2-86.1%. In this population, considering a wide range of biological and psychosocial data did not improve outcome prediction compared to simply-obtained baseline characteristics.
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Restricción Calórica , Técnicas de Apoyo para la Decisión , Alimentos Formulados , Obesidad/dietoterapia , Derivación y Consulta , Pérdida de Peso , Adulto , Índice de Masa Corporal , Árboles de Decisión , Análisis Discriminante , Femenino , Humanos , Modelos Lineales , Modelos Logísticos , Masculino , Persona de Mediana Edad , Obesidad/diagnóstico , Obesidad/fisiopatología , Obesidad/psicología , Valor Predictivo de las Pruebas , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: Obese men commonly have reductions in circulating testosterone and report symptoms consistent with androgen deficiency. We hypothesized that testosterone treatment improves constitutional and sexual symptoms over and above the effects of weight loss alone. METHODS: We conducted a pre-specified analysis of a randomized double-blind, placebo-controlled trial at a tertiary referral center. About 100 obese men (body mass index (BMI)⩾30 kg m-2) with a repeated total testosterone level ⩽12 nmol l-1 and a median age of 53 years (interquartile range 47-60) receiving 10 weeks of a very-low-energy diet (VLED) followed by 46 weeks of weight maintenance were randomly assigned at baseline to 56 weeks of intramuscular testosterone undecanoate (n=49, cases) or matching placebo (n=51, controls). Pre-specified outcomes were the between-group differences in Aging Male Symptoms scale (AMS) and international index of erectile function (IIEF-5) questionnaires. RESULTS: Eighty-two men completed the study. At study end, cases showed significant symptomatic improvement in AMS score, compared with controls, and improvement was more marked in men with more severe baseline symptoms (mean adjusted difference (MAD) per unit of change in AMS score -0.34 (95% confidence interval (CI) -0.65, -0.02), P=0.04). This corresponds to improvements of 11% and 20% from baseline scores of 40 and 60, respectively, with higher scores denoting more severe symptoms. Men with erectile dysfunction (IIEF-5⩽20) had improved erectile function with testosterone treatment. Cases and controls lost the same weight after VLED (testosterone -12.0 kg; placebo -13.5 kg, P=0.40) and maintained this at study end (testosterone -11.4 kg; placebo -10.9 kg, P=0.80). The improvement in AMS following VLED was not different between the groups (-0.05 (95% CI -0.28, 0.17), P=0.65). CONCLUSIONS: In otherwise healthy obese men with mild to moderate symptoms and modest reductions in testosterone levels, testosterone treatment improved androgen deficiency symptoms over and above the improvement associated with weight loss alone, and more severely symptomatic men achieved a greater benefit.
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Andrógenos/uso terapéutico , Dieta Reductora , Terapia de Reemplazo de Hormonas , Hipogonadismo/tratamiento farmacológico , Hipogonadismo/fisiopatología , Obesidad/fisiopatología , Testosterona/uso terapéutico , Envejecimiento , Andrógenos/sangre , Andrógenos/deficiencia , Australia/epidemiología , Depresión , Dieta Reductora/efectos adversos , Método Doble Ciego , Humanos , Hipogonadismo/etiología , Hipogonadismo/psicología , Libido/fisiología , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/complicaciones , Obesidad/psicología , Calidad de Vida , Testosterona/sangre , Resultado del TratamientoRESUMEN
Obesity is a complex disorder that requires a multidisciplinary treatment approach. This review evaluated 3-year outcomes of a very-low-energy diet (VLED)-based programme at a tertiary hospital multidisciplinary weight management clinic. Medical records of all patients who agreed to undertake the VLED programme and who did not undergo bariatric surgery during the 3-year follow-up period were examined. Baseline data collection included demographic and anthropometric characteristics, childhood onset of obesity and co-existing medical conditions. Weight was modelled using a linear mixed effects analysis. Logistic regression analyses were used to model the probability of continuing to attend the clinic and to identify pre-treatment factors associated with longer duration of attendance. Data from 1109 patients were included. A total of 231 patients (19.2%) were still attending the clinic 3 years after their initial appointment. Mean weight loss among patients who attended the clinic for 3 years was 6.4 kg (3.5%, 95% confidence interval [CI] 2.8, 4.2%). People who were prescribed pharmacotherapy maintained greater weight loss at 3 years (7.7% vs. 2.3% without pharmacotherapy, 95% CI for difference 3.9, 7.0%). People who had an onset of obesity in childhood, who had co-existing hypertension or coronary artery disease, and who did not currently smoke were more likely to continue to attend the clinic for up to 3 years. In summary, in an outpatient weight management clinic, patients who undertook a VLED-based programme and continued in follow-up achieved a clinically significant weight loss at 3 years, particularly if pharmacotherapy was used for weight loss maintenance.
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Restricción Calórica , Obesidad/dietoterapia , Servicio Ambulatorio en Hospital , Programas de Reducción de Peso/métodos , Edad de Inicio , Australia , Terapia Combinada , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Obesidad/tratamiento farmacológico , Pacientes Desistentes del Tratamiento , Evaluación de Programas y Proyectos de Salud , Estudios Retrospectivos , Resultado del Tratamiento , Pérdida de PesoRESUMEN
BACKGROUND/OBJECTIVES: Diet-induced weight loss is accompanied by compensatory changes, which increase appetite and encourage weight regain. There is some evidence that ketogenic diets suppress appetite. The objective is to examine the effect of ketosis on a number of circulating factors involved in appetite regulation, following diet-induced weight loss. SUBJECTS/METHODS: Of 50 non-diabetic overweight or obese subjects who began the study, 39 completed an 8-week ketogenic very-low-energy diet (VLED), followed by 2 weeks of reintroduction of foods. Following weight loss, circulating concentrations of glucose, insulin, non-esterified fatty acids (NEFA), ß-hydroxybutyrate (BHB), leptin, gastrointestinal hormones and subjective ratings of appetite were compared when subjects were ketotic, and after refeeding. RESULTS: During the ketogenic VLED, subjects lost 13% of initial weight and fasting BHB increased from (mean±s.e.m.) 0.07±0.00 to 0.48±0.07 mmol/l (P<0.001). BHB fell to 0.19±0.03 mmol/l after 2 weeks of refeeding (P<0.001 compared with week 8). When participants were ketotic, the weight loss induced increase in ghrelin was suppressed. Glucose and NEFA were higher, and amylin, leptin and subjective ratings of appetite were lower at week 8 than after refeeding. CONCLUSIONS: The circulating concentrations of several hormones and nutrients which influence appetite were altered after weight loss induced by a ketogenic diet, compared with after refeeding. The increase in circulating ghrelin and subjective appetite which accompany dietary weight reduction were mitigated when weight-reduced participants were ketotic.
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Regulación del Apetito/fisiología , Hormonas Gastrointestinales/sangre , Cetosis/metabolismo , Pérdida de Peso/fisiología , Ácido 3-Hidroxibutírico/sangre , Adulto , Anciano , Índice de Masa Corporal , Restricción Calórica , Dieta Cetogénica , Ayuno , Ácidos Grasos no Esterificados/sangre , Femenino , Ghrelina/sangre , Humanos , Insulina/sangre , Polipéptido Amiloide de los Islotes Pancreáticos/sangre , Leptina/sangre , Masculino , Persona de Mediana Edad , Obesidad/dietoterapia , Sobrepeso/dietoterapia , Péptido YY/sangre , PosmenopausiaRESUMEN
BACKGROUND/OBJECTIVES: Single-slice abdominal computed tomography or magnetic resonance imaging (MRI) performed to measure visceral adipose tissue in individuals with obesity and diabetes mellitus can also image skeletal muscle. The aim of this study was to validate a method developed in cancer patients using a single abdominal cross-sectional image to estimate fat-free mass (FFM) and appendicular lean tissue mass index (LTMI), a total body skeletal muscle mass surrogate, in an obese cohort of subjects with and without type 2 diabetes. SUBJECTS/METHODS: In total, 49 obese subjects (22 with diabetes) recruited into a weight loss study underwent dual-energy X-ray absorptiometry (DXA) and abdominal MRI at baseline. DXA-derived FFM and LTMI were compared with skeletal muscle area at the level of the third lumbar vertebra (L3) on MRI. RESULTS: L3 skeletal muscle area correlated with FFM (R (adj) (2)=0.825; P<0.001) and LTMI (R (adj) (2)=0.6; P<0.001). A simple formula, previously shown to predict LTMI in cancer patients, produced a good estimation of LTMI from L3 skeletal muscle area (95% confidence interval -3.70, 2.56%) in our obese cohort. Equations incorporating age, sex, height, weight and diabetic status improved the relationship between L3 skeletal muscle area and estimated FFM (r=0.976, P<0.001) and LTMI (r=0.879, P<0.001). CONCLUSION: A single-axial slice at the L3 level can be used to estimate FFM and LTMI in obese diabetic and non-diabetic subjects, allowing precise analysis of body composition using a single imaging modality in clinical research and practice.