Behavioural counselling to increase consumption of fruit and vegetables in low income adults: randomised trial

ObjectiveTo measure the effect of brief behavioural counselling in general practice on patients'' consumption of fruit and vegetables in adults from a low income population.DesignParallel group randomised controlled trial.SettingPrimary health centre in a deprived, ethnically mixed inner city area.Participants271 patients aged 18-70 years without serious illness.InterventionBrief individual behavioural counselling based on the stage of change model; time matched nutrition education counselling.ResultsConsumption of fruit and vegetables increased from baseline to 12 months by 1.5 and 0.9 portions per day in the behavioural and nutrition groups (mean difference 0.6 portions, 95% confidence interval 0.1 to 1.1). The proportion of participants eating five or more portions a day increased by 42% and 27% in the two groups (mean difference 15%, 3% to 28%). Plasma β carotene and α tocopherol concentrations increased in both groups, but the rise in β carotene was greater in the behavioural group (mean difference 0.16 μmol/l, 0.001 μmol/l to 1.34 μmol/l). There were no changes in plasma ascorbic acid concentrations or urinary potassium excretion. Differences were maintained when analysis was restricted to the 177 participants with incomes ≤£400 (€596, $640) a week.ConclusionsBrief individual counselling in primary care can elicit sustained increases in consumption of fruit and vegetables in low income adults in the general population.

What is already known on this topic

Brief interventions can be effective in increasing consumption of fruit and vegetablesBiomarkers and intention to treat analyses have seldom been used in such interventions, and few studies have targeted low income populations

What this study adds

Compared with nutritional counselling, brief behavioural counselling carried out by nurses in primary care led to greater increases in fruit and vegetable intake and in plasma β carotene concentrationFavourable effects were observed in low income adults living in a deprived inner city area     

Determination of the optimal therapeutic protocols in cancer immunotherapy

Cancer immunotherapy aims at eliciting an immune system response against the tumor. However, it is often characterized by toxic side-effects. Limiting the tumor growth and, concurrently, avoiding the toxicity of a drug, is the problem of protocol design. We formulate this question as an optimization problem and derive an algorithm for its solution. Unlike the standard optimal control approach, the algorithm simulates impulse-like drug administrations. It relies on an exact computation of the gradient of the cost function with respect to any protocol by means of the variational equations, that can be solved in parallel with the system. In comparison with previous versions of this method [F. Castiglione, B. Piccoli, Optimal control in a model of dendritic cell transfection cancer immunotherapy, Bull. Math. Biol. 68 (2006) 255-274; B. Piccoli, F. Castiglione, Optimal vaccine scheduling in cancer immunotherapy, Physica A. 370 (2) (2007) 672-680], we optimize both the timing and the dosage of each administration and introduce a penalty term to avoid clustering of subsequent injections, a requirement consistent with the clinical practice. In addition, we implement the optimization scheme to simulate the case of multi-therapies. The procedure works for any ODE system describing the pharmacokinetics and pharmacodynamics of an arbitrary number of therapeutic agents. In this work, it was tested for a well known model of the tumor-immune system interaction [D. Kirschner, J.C. Panetta, Modeling immunotherapy of tumor-immune interaction, J. Math. Biol. 37 (1998) 235-252]. Exploring three immunotherapeutic scenarios (CTL therapy, IL-2 therapy and combined therapy), we display the stability and efficacy of the optimization method, obtaining protocols that are successful compromises between various clinical requirements.     

Kidney stones and hypertension: population based study of an independent clinical association.

OBJECTIVE--To test the hypothesis that kidney stone disease is more frequent among hypertensive men when the effect of possible confounders is allowed for. DESIGN--Cross sectional study of a sample of the male working population conducted as part of the 10 year follow up of a nationwide survey of the prevalence of cardiovascular risk factors. SETTING--The Olivetti factory in Pozzuoli, a suburban area of Naples. POPULATION--688 Male workers (87.9% of the male workforce) aged 21-68. INTERVENTIONS--Anthropometric and blood pressure measurements, blood tests, and administration of a detailed questionnaire aimed at detecting a history of urolithiasis. MAIN OUTCOME MEASURES--Prevalence of a history of urolithiasis among normotensive and untreated and treated hypertensive men adjusted for the possible confounding effects of age, body mass index, renal function, and serum urate and total calcium concentrations. RESULTS--Of the 688 participants 509 were normotensive. Of the remainder, 118 had untreated and 61 treated hypertension. The overall prevalence of a history of urolithiasis was 16.3% (112/688). The relative risk of hypertensive subjects having a history of kidney stones was twice that of the normotensive group (odds ratio 2.11; 95% confidence interval 1.17 to 3.81), the risk being higher when only treated hypertensives were considered (odds ratio 3.16; 95% confidence interval 1.75 to 5.71). The prevalence of a history of urolithiasis was 13.4% (68/509) in the normotensive subjects, 20.3% (24/118) in the untreated hypertensives, and 32.8% (20/61) in the treated hypertensives (p less than 0.001). The age adjusted relative risk in treated hypertensive men was higher than that in the normotensive group (Mantel-Haenszel pooled estimate of odds ratio 2.63; 95% confidence interval 2.23 to 3.10). CONCLUSION--An independent clinical association exists between the occurrence of urolithiasis and hypertension. The increased urinary calcium excretion commonly detected in hypertension may be the pathogenetic link.     

Lack of effect of oral magnesium on high blood pressure: a double blind study.

Seventeen unselected patients with mild to moderate essential hypertension and whose average supine blood pressure after two months'' observation with no treatment was 154/100 mm Hg were entered into a double blind randomised crossover study of one month''s treatment with magnesium aspartate (15 mmol magnesium/day) and treatment with placebo for a further month. This preparation of magnesium was well tolerated and did not cause diarrhoea. Despite a significant increase in plasma magnesium concentration and a significant increase in urinary excretion of magnesium while taking magnesium aspartate there was no fall in blood pressure compared with either treatment with placebo or values before treatment. The results provide no evidence for a role of dietary magnesium in the regulation of high blood pressure and are contrary to recent speculations.