Body mass index and dental caries in young people: a systematic review.

BACKGROUND: Obesity and caries in young people are issues of public health concern. Even though research into the relationship between the two conditions has been conducted for many years, to date the results remain equivocal. The aim of this paper was to determine the nature of the relationship between Body Mass Index (BMI) and caries in children and adolescents, by conducting a systematic review of the published literature. METHODS: A systematic search of studies examining the association between BMI and caries in individuals younger than 18 years old was conducted. The electronic bibliographic databases PubMed, MEDLINE, Embase, CINAHL, CENTRAL and Google Scholar were searched. References of included studies were checked to identify further potential studies. Internal and external validity as well as reporting quality were assessed using the validated Methodological Evaluation of Observational Research checklist. Results were stratified based on the risk of flaws in 14 domains 10 of which were considered major and four minor. RESULTS: Of the 4208 initially identified studies, 84 papers met the inclusion criteria and were included in the review; conclusions were mainly drawn from 7 studies at lower risk of flaws. Three main types of association between BMI and caries were found: 26 studies showed a positive relationship, 19 showed a negative association, and 43 found no association between the variables of interest. Some studies showed more than one pattern of association. Assessment of confounders was the domain most commonly found to be flawed, followed by sampling and research specific bias. Among the seven studies which were found to be at lower risk of being flawed, five found no association between BMI and caries and two showed a positive association between these two variables. CONCLUSIONS: Evidence of an association between BMI and caries was inconsistent. Based on the studies with a low risk lower risk of being flawed, a positive association between the variables of interest was found mainly in older children. In younger children, the evidence was equivocal. Longitudinal studies examining the association between different indicators of obesity and caries over the life course will help shed light in their complex relationship.

Barrett's oESophagus trial 3 (BEST3): study protocol for a randomised controlled trial comparing the Cytosponge-TFF3 test with usual care to facilitate the diagnosis of oesophageal pre-cancer in primary care patients with chronic acid reflux.

BACKGROUND: Early detection of oesophageal cancer improves outcomes; however, the optimal strategy for identifying patients at increased risk from the pre-cancerous lesion Barrett's oesophagus (BE) is not clear. The Cytosponge, a novel non-endoscopic sponge device, combined with the biomarker Trefoil Factor 3 (TFF3) has been tested in four clinical studies. It was found to be safe, accurate and acceptable to patients. The aim of the BEST3 trial is to evaluate if the offer of a Cytosponge-TFF3 test in primary care for patients on long term acid suppressants leads to an increase in the number of patients diagnosed with BE. METHODS: The BEST3 trial is a pragmatic multi-site cluster-randomised controlled trial set in primary care in England. Approximately 120 practices will be randomised 1:1 to either the intervention arm, invitation to a Cytosponge-TFF3 test, or the control arm usual care. Inclusion criteria are men and women aged 50 or over with records of at least 6 months of prescriptions for acid-suppressants in the last year. Patients in the intervention arm will receive an invitation to have a Cytosponge-TFF3 test in their general practice. Patients with a positive TFF3 test will receive an invitation for an upper gastro-intestinal endoscopy at their local hospital-based endoscopy clinic to test for BE. The primary objective is to compare histologically confirmed BE diagnosis between the intervention and control arms to determine whether the offer of the Cytosponge-TFF3 test in primary care results in an increase in BE diagnosis within 12 months of study entry. DISCUSSION: The BEST3 trial is a well-powered pragmatic trial testing the use of the Cytosponge-TFF3 test in the same population that we envisage it being used in clinical practice. The data generated from this trial will enable NICE and other clinical bodies to decide whether this test is suitable for routine clinical use. TRIAL REGISTRATION: This trial was prospectively registered with the ISRCTN Registry on 19/01/2017, trial number ISRCTN68382401 .

Obesity and caries in four-to-six year old English children: a cross-sectional study.

BACKGROUND: Obesity and caries are common conditions in childhood and can have significant implications on children's wellbeing. Evidence into their association remains conflicting. Furthermore, studies examining the ssociation between obesity and caries commonly focus on individual-level determinants. The present study aimed to examine the association between obesity and caries in young English children and to determine the impact of deprivation and area-level characteristics on the distribution of the two conditions. METHODS: This was a cross-sectional study among children in Plymouth city aged four-to-six years. Anthropometric measurements included weight and height (converted to Body Mass Index centiles and z-scores), and waist circumference. Caries was assessed by using the sum of the number of teeth that were decayed, missing or filled. A questionnaire was used to obtain information on children's demographic characteristics, oral hygiene, and dietary habits. The impact of deprivation on anthropometric variables and caries was determined using Linear and Poisson regression models, respectively. Multiple logistic regression was used to assess the association between different anthropometric measures and caries. Logistic regression models were also used to examine the impact of several demographic characteristics and health behaviours on the presence of obesity and caries. RESULTS: The total sample included 347 children aged 5.10 ± 0.31 (mean ± SD). Deprivation had a significant impact on caries and BMI z-scores (p < 0.05). Neither BMI- nor waist circumference z-scores were shown to be significantly associated with dental caries. Among the neighbourhood characteristics examined, the percentage of people dependent on benefits was found to have a significant impact on caries rates (p < 0.05). Household's total annual income was inversely related to caries risk and parental educational level affected children's tooth brushing frequency. CONCLUSIONS: No associations between any measure of obesity and caries were found. However, deprivation affected both obesity and caries, thus highlighting the need to prioritise disadvantaged children in future prevention programmes.

Partial-likelihood analysis of spatio-temporal point-process data.

We investigate the use of a partial likelihood for estimation of the parameters of interest in spatio-temporal point-process models. We identify an important distinction between spatially discrete and spatially continuous models. We focus our attention on the spatially continuous case, which has not previously been considered. We use an inhomogeneous Poisson process and an infectious disease process, for which maximum-likelihood estimation is tractable, to assess the relative efficiency of partial versus full likelihood, and to illustrate the relative ease of implementation of the former. We apply the partial-likelihood method to a study of the nesting pattern of common terns in the Ebro Delta Natural Park, Spain.