Prevention of headache in adolescents: population-attributable risk fraction for risk factors amenable to intervention.

INTRODUCTION: Several risk factors for headache have been identified, some of which are potentially amenable to interventions. The potential effect of such interventions can be predicted by the population-attributable risk fraction (PARF). We assessed PARFs of the the following risk factors: neck muscle pain, chronic stress, alcohol consumption, smoking, coffee consumption, and physical inactivity. We studied the maximal possible effect achievable by avoidance of these risk factors. METHODS: Two approaches to estimate PARFs are compared, which assess their cumulative and individual impact of risk factors by age: the Levin formula and the average attributable fraction. RESULTS: The overall impact for removal of all six risk factors amounts to 19.7% for the average attributable fraction. Neck tension and consumption of alcohol ranked as the strongest population-attributable risk factor for any headache. The potential impact for migraine was considerably higher (43.8%). With increasing age, the overall impact of risk factors on headache increases by 18.9%. CONCLUSION: Based on the estimations of the most appropriate approach, up to 20% of headaches in general and up to 43% of migraine in adolescents might be preventable by removing risk factors amenable to intervention, with increasing proportions by age.

Validation and extension of a simple questionnaire to assess physical activity in pre-school children.

OBJECTIVE: To (i) validate a recently proposed questionnaire tool for the simple assessment of physical activity (PA) in pre-school children by comparison with accelerometry and heart-rate recordings; and (ii) extend the tool by adding more questions to improve validity and to refine the classification from two to three categories (PA low, medium, high). SETTING: Baseline data of an intervention evaluation study. SUBJECTS: Pre-school children. DESIGN: Children were categorized as either physically active or non-active, based on their parents' answers to the five-item questionnaire. Activity and heart rate were recorded for 6 d (Actiheart device; CamNtech, Cambridge, UK). Nightly sleeping periods were removed and mean accelerometry counts (MACT), time spent in moderate-to-vigorous intensity physical activity (MVPA) and time spent in sedentary behaviour (SB) were computed. In a second step, additional questions that improved validity were added, resulting in an extended seven-item questionnaire. RESULTS: For 748 (90·4 %) of the participating children aged 2·3-6·7 years, the questionnaires were filled out sufficiently for classification. Children classified as physically active showed 9·6 % higher MACT (P < 0·0003), spent more time in MVPA and insignificantly less time in SB. Using the extended questionnaire, children with PA classified as medium (reference: low) showed 11·0 % more MACT, spent 11·8 % more time in MVPA and 4·8 % less time in SB. Children with PA classified as high showed 16·9 % more MACT, spent 20·2 % more time in MVPA and 7·2 % less time in SB. CONCLUSIONS: With validated PA questionnaires for pre-school children lacking, the proposed questionnaire might be a reasonable option to include for PA assessment in epidemiological studies where more elaborate measurements are unavailable.

Prenatal and postnatal tobacco exposure and behavioral problems in 10-year-old children: results from the GINI-plus prospective birth cohort study.

BACKGROUND: Prenatal and postnatal tobacco exposure have been reported to be associated with behavioral problems. However, the magnitude of the association with tobacco exposure at specific periods of exposure is unclear. OBJECTIVE: We assessed the relative risk of behavioral problems in children who had been exposed to tobacco smoke in utero and postnatally. METHODS: We analyzed data from a prospective birth cohort study in two cities in Germany: the German Infant Nutrition Intervention. Our sample included 5,991 children born between 1995 and 1998 as well as their parents. We measured behavioral problems using the Strength and Difficulties Questionnaire (SDQ) at follow-up 10 years after birth. According to prespecified SDQ cutoff values, children were classified as "normal," "borderline," or "abnormal" according to the subscales "emotional symptoms," "conduct problems," "hyperactivity/inattention," "peer-relationship problems," and a total difficulties score. Smoke exposure and further covariates were assessed using parent questionnaires. RESULTS: Compared with children not exposed to tobacco smoke, children exposed both pre- and postnatally to tobacco smoke had twice the estimated risk [95% confidence interval (CI), 1.4-3.1] of being classified as abnormal according to the total difficulties score of the SDQ at 10 years of age. Children who were only prenatally exposed had a 90% higher relative risk (95% CI, 0.9-4.0), whereas children who were only postnatally exposed had a 30% higher relative risk (95% CI, 0.9-1.9). These results could not be explained by confounding by parental education, father's employment, child's time spent in front of computer or television screen, being a single father or mother, or mother's age. CONCLUSIONS: Prenatal exposure to tobacco smoke is associated with behavioral problems in school-age children. Although our findings do not preclude the influence of postnatal exposure, prenatal exposure seems to be more important.

Short- and mid-term effects of a setting based prevention program to reduce obesity risk factors in children: a cluster-randomized trial.

BACKGROUND & AIMS: To assess the effects of a low cost behavioral prevention program in a preschool setting. METHODS: 64 Kindergartens in 4 Bavarian regions were randomly assigned as intervention or controls in a 2:1 ratio. Samples of 1318 and 1340 children examined in the school entrance health examination at 5.7+/-2.6 and 17.6+/-2.3 months (mean+/-standard deviation for first and second sample) after the start of the program were analysed. MEASUREMENTS: Main outcome measures were the prevalence of high fruit and vegetable consumption, low consumption of high caloric drinks assessed in parental questionnaires, overweight and obesity, and secondary, further dietary habits and results of motoric testing. RESULTS: The program led to an increased proportion of children with high fruit and vegetable consumption already after 6 months, which was sustainable with adjusted odds ratios of 1.59 (1.26: 2.01) and 1.48 (1.08: 2.03) after 18 months. Subgroup analyses by gender, overweight and parental education, performed in order to assess consistency of effects, showed similar results. Prevalence of overweight and obesity as well as motoric testing results were not statistically different between intervention and control groups. CONCLUSION: This low cost setting based behavioral intervention achieved sustainable effects on fruit and vegetable consumption in young children 18 months after the start of the intervention and showed effects also in the high risk groups of children from families with lower education levels, and children already overweight.

A simple assessment of physical activity is associated with obesity and motor fitness in pre-school children.

OBJECTIVE: Physical activity is an important determinant of energy balance. However, its impact on overweight/obesity has proved difficult to measure in pre-school children and few studies have found significant associations. A set of simple questions was used to distinguish pre-school children with high and low physical activity, and the association of this classification with childhood overweight/obesity and performance in an established motor test was investigated. DESIGN: Survey, cross-sectional. SETTING AND SUBJECTS: Weight and height were measured in 12,556 children taking part in the obligatory school entrance health examination 2004-5 and 2005-6 in three urban and three rural Bavarian regions. Their parents were asked to answer a questionnaire with a set of questions on physical activity. RESULTS: The mean age of the children evaluated was 5.78 (sd 0.43) years, 6535 (52.1 %) were boys. Physically active children were less likely to be overweight (OR = 0.786, 95 % CI 0.687, 0.898) or obese (OR = 0.655, 95 % CI 0.506, 0.849) and achieved 6.7 (95 % CI 5.8, 7.7) % more jumps per 30 s than less active children in a motor test, adjusted for a number of potentially confounding variables. CONCLUSIONS: Classification of pre-school children as physically active or not, based on a small set of questions, revealed significant associations with overweight/obesity and a motor test. Once further validated, this classification might provide a valuable tool to assess the impact of physical activity on the risk of childhood overweight and obesity.