Changes in adolescents' intake of sugar-sweetened beverages and sedentary behaviour: results at 8 month mid-way assessment of the HEIA study--a comprehensive, multi-component school-based randomized trial

Background

Inconsistent effects of school-based obesity prevention interventions may be related to how different subgroups receive them. The aim of this study was to evaluate the effect of an intervention program, including fact sheets to parents and classroom components, on intake of sugar-sweetened beverages (SSB) and screen time. Further, to explore whether potential effects and parental involvement varied by adolescents' gender, weight status (WS) and parental educational level.

Methods

In total, 1465 11-year-olds participated at the pre-test and the 8 month mid-way assessment of the HEIA study. Parents (n = 349) contributed with process evaluation data. Self-reported intake of SSB was collected from the 11-year-olds assessing frequency and amount, while time used on watching TV/DVD and computer/game-use (weekday and weekend day) were assed by frequency measures. Data on awareness of the intervention and dose received were collected from parents. Covariance analyses (ANCOVA) were conducted testing for effects by gender and for moderation by WS and parental education.

Results

Time spent on TV/DVD (week p = 0.001, weekend p = 0.03) and computer/game-use (week p = 0.004, weekend p <.001), and the intake of SSB during weekend days (p = 0.04), were significantly lower among girls in the intervention group compared to the control group girls after 8 months. Girls' WS did not moderate these findings. However, no significant effects of the intervention were found for boys, but moderation effects were found for WS (week days: TV/DVD, p = 0.03 and computer/games, p = 0.02). There were no moderating effects of parental education for neither boys nor girls with respect to intake of SSB, time used for watching TV/DVD and computer/game-use. Parental awareness of the intervention was significantly higher among the parents of girls, while the parents of boys were more satisfied with the fact sheets.

Conclusions

The preventive initiatives appeared to change behaviour in girls only. This study suggests that exploration of potential beneficial or negative effects of intervention in subgroups is important. In formative evaluation of obesity prevention studies it seems warranted to include issues related to gender, WS and parental involvement in order to enhance the effectiveness of preventive initiatives.

Estimating usual food intake distributions by using the multiple source method in the EPIC-Potsdam Calibration Study

Estimating usual food intake distributions from short-term quantitative measurements is critical when occasionally or rarely eaten food groups are considered. To overcome this challenge by statistical modeling, the Multiple Source Method (MSM) was developed in 2006. The MSM provides usual food intake distributions from individual short-term estimates by combining the probability and the amount of consumption with incorporation of covariates into the modeling part. Habitual consumption frequency information may be used in 2 ways: first, to distinguish true nonconsumers from occasional nonconsumers in short-term measurements and second, as a covariate in the statistical model. The MSM is therefore able to calculate estimates for occasional nonconsumers. External information on the proportion of nonconsumers of a food can also be handled by the MSM. As a proof-of-concept, we applied the MSM to a data set from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam Calibration Study (2004) comprising 393 participants who completed two 24-h dietary recalls and one FFQ. Usual intake distributions were estimated for 38 food groups with a proportion of nonconsumers > 70% in the 24-h dietary recalls. The intake estimates derived by the MSM corresponded with the observed values such as the group mean. This study shows that the MSM is a useful and applicable statistical technique to estimate usual food intake distributions, if at least 2 repeated measurements per participant are available, even for food groups with a sizeable percentage of nonconsumers.

The STORK Groruddalen research programme: A population-based cohort study of gestational diabetes, physical activity, and obesity in pregnancy in a multiethnic population. Rationale, methods, study population, and participation rates

BACKGROUND

Gestational diabetes mellitus (GDM) and obesity may cause adverse pregnancy outcomes for mothers and offspring. We have set up a research programme to identify predictors for GDM and fetal growth in a multiethnic population in Oslo to improve the identification of high risk pregnancies and reduce adverse short and long-term outcomes for mothers and offspring.

AIMS

To present the rationale, methods, study population and participation rates.

METHODS

Population-based cohort study of pregnant women attending the Child Health Clinics (CHC) in Groruddalen, Oslo, and their offspring. Questionnaire data, blood pressure, anthropometric measurements, and fasting blood and urine samples are collected (gestational weeks 8-20 and 28, and 12 weeks postpartum) and an oral glucose tolerance test (28 weeks). Physical activity is measured, three ultrasound measurements are performed and paternal questionnaire data collected. Routine hospital data are available for all mothers and offspring. Umbilical venous blood and placentas are collected, sampled, and stored and neonatal anthropometric measurements performed. Ethnicity is self-reported country of birth.

RESULTS

823 women were included, 59% of non-Western origin. The participation rate was 74% (64-83% in main ethnic groups), mean age 29.8 years (95% CI 29.5-30.1) and median parity 1 (inter-quartile range 1). The cohort is representative for women attending the CHC with respect to ethnicity and age. A slight selection towards lower parity (South Asians) and age (Africans) was found. Few were lost to follow-up.

CONCLUSIONS

Unique information is collected from a representative group of multiethnic women to address important public health problems and mechanisms of disease. Participation rates are high in all ethnic groups.

Evaluation of energy and dietary intake estimates from a food frequency questionnaire using independent energy expenditure measurement and weighed food records

Background

We have developed a food frequency questionnaire (FFQ) for the assessment of habitual diet, with special focus on the intake of fruit, vegetables and other antioxidant-rich foods and beverages. The aim of the present study was to evaluate the relative validity of the intakes of energy, food and nutrients from the FFQ.

Methods

Energy intake was evaluated against independent measures of energy expenditure using the ActiReg^® system (motion detection), whereas 7-days weighed food records were used to study the relative validity of food and nutrient intake. The relationship between methods was investigated using correlation analyses and cross-classification of participants. The visual agreement between the methods was evaluated using Bland-Altman plots.

Results

We observed that the FFQ underestimated the energy intake by approximately 11% compared to the energy expenditure measured by the ActiReg^®. The correlation coefficient between energy intake and energy expenditure was 0.54 and 32% of the participants were defined as under-reporters. Compared to the weighed food records the percentages of energy from fat and added sugar from the FFQ were underestimated, whereas the percentage of energy from total carbohydrates and protein were slightly overestimated. The intake of foods rich in antioxidants did not vary significantly between the FFQ and weighed food records, with the exceptions of berries, coffee, tea and vegetables which were overestimated. Spearman's Rank Order Correlations between FFQ and weighed food records were 0.41 for berries, 0.58 for chocolate, 0.78 for coffee, 0.61 for fruit, 0.57 for fruit and berry juices, 0.40 for nuts, 0.74 for tea, 0.38 for vegetables and 0.70 for the intake of wine.

Conclusions

Our new FFQ provides a good estimate of the average energy intake and it obtains valid data on average intake of most antioxidant-rich foods and beverages. Our study also showed that the FFQs ability to rank participants according to intake of total antioxidants and most of the antioxidant-rich foods was good.

Maternal consumption of coffee and caffeine-containing beverages and oral clefts: a population-based case-control study in Norway

A large, population-based case-control study of facial clefts was carried out in Norway between 1996 and 2001. The study included 573 cases -- 377 with cleft lip with or without cleft palate and 196 with cleft palate only -- and 763 randomly selected controls. Maternal consumption of coffee and other caffeine-containing beverages in early pregnancy was recorded shortly after birth. Compared with that for no coffee consumption, the adjusted odds ratios for cleft lip with or without cleft palate were 1.39 (95% confidence interval: 1.01, 1.92) for less than 3 cups a day and 1.59 (95% confidence interval: 1.05, 2.39) for 3 cups or more. Coffee consumption was not associated with risk of cleft palate only (for > or = 3 cups vs. none, adjusted odds ratio = 0.96, 95% confidence interval: 0.55, 1.67). Tea consumption was associated with a reduced odds ratio of both cleft lip with or without cleft palate and cleft palate only. There was little evidence of an association between caffeine exposure and clefts when all sources of caffeine were considered. Adjustment for known confounding factors in general had minor effects on risk estimates. Still, the authors could not rule out the possibility of uncontrolled confounding by factors associated with the habit of drinking coffee.

Physical activity and overweight in children and adolescents using intensified insulin treatment

AIM

To describe physical activity and inactivity and parameters associated with overweight in a population-based study of children and adolescents on intensive insulin treatment.

METHODS

Physical activity and inactivity were evaluated in 723 type 1 diabetic subjects, 240 children aged 6-10 yr and 483 adolescents aged 11-19 yr, using a questionnaire that can estimate total amount of time spent on inactivity and light, moderate and vigorous activity.

RESULTS

Overall, 54% of the participants do not fulfil the international recommendations of 60 min of moderate-to-vigorous activity per day. Girls are less active than boys in childhood (70 vs. 88 min/d, p = 0.01) and in adolescence (47 vs. 57 min/d, p = 0.02). Furthermore, this study shows that those who are more active are also those who seldom skip meals (p < 0.001). Forty-three percent of the participants watch TV for more than 2 h a day, and TV viewing was found to be related to overweight in children and adolescents with type 1 diabetes [OR: 2.5 (1.40-4.54), p = 0.002]. No statistical differences in physical activity were noted between the different intensified insulin regimens. Patients wearing insulin pumps were not less active.

CONCLUSION

To increase physical activity to recommended level and limit TV viewing should be an important issue in education of all children and adolescents with type 1 diabetes, independent of insulin regimen.

Sweets, snacking habits, and skipping meals in children and adolescents on intensive insulin treatment

AIM

To examine the association between skipping meals and snacking events and dietary and clinical characteristics in children and adolescents using modern insulin treatment.

METHODS

Dietary intake was recorded for 4 d in food diaries in 655 young diabetic patients. Number of meals and snacking events was recorded in a separated questionnaire, while clinical data were obtained from case record forms. Skipping meals refer to consuming a main meal (e.g., breakfast) five times a week or less.

RESULTS

Modern insulin treatment may favor a more flexible lifestyle. This study shows that there are fewer young diabetic patients who skip meals than non-diabetic controls (p < 0.001) even when using modern intensified insulin treatment. However, skipping meals among young diabetic patients was associated with negative characteristics such as having suboptimal hemoglobin A1c (HbA1c) (OR 4.7, p = 0.02), higher low-density lipoprotein (LDL) cholesterol levels (OR 4.0, p < 0.001), watching more TV (OR 3.6, p < 0.001), being overweight (OR 2.8, p = 0.03), as well as having a higher intake of added sugar (OR 2.1, p = 0.01) and lower intake of fiber (OR 0.2, p = 0.04) compared with those not skipping meals. Having more than two snacking events during the day was associated with higher HbA1c, higher intake of added sugar and sweets, and spending more hours in front of the TV or personal computer.

CONCLUSIONS

In general, fewer children and adolescents with type 1 diabetes skip meals compared with healthy peers. Those who skip meals and have more snacking events have poorer glycemic control and less healthy dietary and leisure habits.

Maternal dietary intake of vitamin A and risk of orofacial clefts: a population-based case-control study in Norway

A population-based case-control study was carried out in Norway between 1996 and 2001. The aim was to evaluate the association between maternal intake of vitamin A from diet and supplements and risk of having a baby with an orofacial cleft. Data on maternal dietary intake were available from 535 cases (188 with cleft palate only and 347 with cleft lip with or without cleft palate) and 693 controls. The adjusted odds ratio for isolated cleft palate only was 0.47 (95% confidence interval: 0.24, 0.94) when comparing the fourth and first quartiles of maternal intake of total vitamin A. In contrast, there was no appreciable association of total vitamin A with isolated cleft lip with or without cleft palate. An intake of vitamin A above the 95th percentile was associated with a lower estimated risk of all isolated clefts compared with the 40th-60th percentile (adjusted odds ratio = 0.48, 95% confidence interval: 0.20, 1.14). Maternal intake of vitamin A is associated with reduced risk of cleft palate only, and there is no evidence of increased risk of clefts among women in our study with the highest 5% of vitamin A intake.

The influence of dietary intake and meal pattern on blood glucose control in children and adolescents using intensive insulin treatment

AIMS/HYPOTHESIS

We studied dietary factors and their association with blood glucose control in type 1 diabetic children and adolescents using intensive insulin treatment.

MATERIALS AND METHODS

A total of 550 children and adolescents with type 1 diabetes mellitus (age 2-19 years) recorded their diet for 4 days in pre-coded food diaries. Of the study group, 34% used insulin pumps, 43% used four or more injections and 16% three injections per day. HbA(1c) was related to targets of optimal blood glucose control defined by the International Society for Pediatric and Adolescent Diabetes (ISPAD).

RESULTS

Adolescents with optimal glucose control (HbA(1c) < or = 7.5%) had a lower intake of added sugar (7.7 vs 9.1% of energy intake, p = 0.004), a higher intake of fibre (19.3 vs 17.0 g/day, p = 0.01) and a higher intake of fruits and vegetables (257 vs 227 g/day, p = 0.04) than those with suboptimal metabolic control (HbA(1c) > 7.5%). Multiple regression analysis in adolescents showed that fibre and meal pattern were significantly associated with blood glucose control (effect fibre intake = -0.02, p = 0.04, effect having breakfast regularly = -0.89, p = 0.009). In children meal pattern was associated with blood glucose control (effect having dinner regularly = -0.66, p = 0.02, effect having supper regularly = -0.78, p = 0.03).

CONCLUSIONS/INTERPRETATION

In diabetic adolescents both intake of fibre and having a regular meal pattern are associated with blood glucose control. Lower intake of added sugar and sugar-sweetened soft drinks and higher intake of fruits and vegetables are observed among those with optimal compared with those with suboptimal blood glucose control. Dietary guidance should be intensified during adolescence to improve dietary intake and blood glucose control.

Validation of a pre-coded food diary with energy expenditure, comparison of under-reporters v. acceptable reporters

The objective of the present study was to compare energy intake (EI) assessed from a pre-coded food diary (PFD) with energy expenditure (EE) measured by a validated position-and-movement monitor (ActiReg®; PreMed AS, Oslo, Norway) in a group of Norwegian 9-year-olds. Moreover, we examined whether and how under-reporters (UR), identified with ActiReg®, differed from acceptable reporters (AR) according to food intake and BMI. A total of fifty-one 9-year-olds completed PFD and ActiReg®. The present study showed that on average EI was underestimated by 18 % compared with EE measured by ActiReg®. The 95 % confidence limits of agreement in a Bland–Altman plot for EI and EE varied from 1·97 MJ to −4·23 MJ (sd 2) among the girls and from 0·74 MJ to −5·26 MJ (sd 2) among the boys. The Pearson correlation coefficient between EI and EE was 0·28 (P=0·05) for males and females combined. Fifty-seven per cent of the participants were classified as AR, 39 % as UR and 4 % as over-reporters with the PFD. Under-reporting of energy remains a problem with the PFD method used in a group of 9-year-olds, especially among boys. However, UR and AR did not show a systematic misreporting related to macronutrients, unhealthy foods or BMI.

Children and adolescents with type 1 diabetes eat a more atherosclerosis-prone diet than healthy control subjects

AIMS/HYPOTHESIS

We evaluated how well the diet of Norwegian children and adolescents with type 1 diabetes fulfils the Nordic and European dietary recommendations, focusing on parameters affecting prevention of atherosclerosis. We also compared the diet of this patient group with that of healthy same-age control subjects.

MATERIALS AND METHODS

A total of 177 children and adolescents with type 1 diabetes (9-10-year-olds, 12-13-year-olds) and 1,809 healthy same-age control subjects recorded their food intake for 4 days in precoded food diaries.

RESULTS

In children and adolescents with type 1 diabetes the percentage of energy (E%) from fat (33-35 E%) and saturated fat (14-15 E%) was higher than recommended for that group. Furthermore their intake of fibre was lower (16-19 g/day) than current recommendations. There were no differences in energy intake between diabetic subjects and healthy control subjects. Percentage of energy from fat (mean difference: 3.4 E%, p < 0.001) and saturated fat (mean difference: 1.0 E%, p < 0.001) was significantly higher among diabetic subjects than control subjects. Intake of fruits and vegetables was low (210 g/day) compared with recommendations, both in the diabetic and control subjects.

CONCLUSIONS/INTERPRETATION

Diabetic children and adolescents had a high intake of energy from saturated fat and low intake of fibre, fruits and vegetables, which could increase the risk of development of atherosclerosis. This study supports the idea that nutritional guidance in the treatment of children and adolescents with type 1 diabetes should be more focused, especially with regard to intake of fibre, fruits and vegetables and to quality and quantity of fat intake.

Validation of a semi-quantitative food-frequency questionnaire used among 2-year-old Norwegian children

Objectives:

An adequate diet is of profound importance in infancy and early childhood. To ensure an optimal diet, knowledge about actual intake must be obtained. The aims of this study were to assess the validity of a semi-quantitative food-frequency questionnaire (SFFQ) applied in a large nation-wide survey among 2-year-old children and to examine the validity of the SFFQ in relation to different background parameters.

Design:

The SFFQ was administered to the parents close to the child's second birthday, and one to two weeks later they started to weigh and record the child's diet for 7 days.

Subjects:

One-hundred and eighty-seven families with a 2-year-old child completed both methods.

Results:

There were no differences between the intakes of protein, saturated fatty acids, total carbohydrates and calcium estimated from the two methods. The average intake of all micronutrients, except for calcium, was overestimated by the SFFQ. Bland–Altman plots showed a systematic increase in difference between the two methods with increasing intake for most nutrients. Spearman correlation coefficients between methods for nutrient intakes ranged from 0.26 to 0.50, the median correlation was 0.38. The correlations increased when estimates were adjusted for energy intake, the median correlation being 0.52. Differences in observed validity were found according to the number of siblings.

Conclusions:

This study indicates that the SFFQ may be a valuable tool for measuring average intakes of energy, macronutrients and several food items among a 2-year-old population in Norway. The ability of the questionnaire to rank children according to intakes of nutrients and food items was rather low.

Validity of a questionnaire to assess fruit and vegetable intake in adults

OBJECTIVE

To validate a method for assessing fruit and vegetable intake among adults in a population of low intake. The method assesses mean intake and ranks individuals by their usual intake.

DESIGN

A precoded fruit and vegetable Questionnaire included a 24-h recall and a food frequency. The participants filled in the Questionnaire, a week later they started a 7-day food record, 1-day weighed record and 6 days using household measures.

SUBJECTS

Following advertisements 40 participants were recruited, 36 returned food records(mean age=37 years).

RESULTS

No difference was observed between the average intake yielded by the 24-h recall and that from the 1-day weighed food record of fruits or vegetables. Correlation coefficients between results from the food frequency questionnaire and the 7-day food records were 0.45 (P=0.007) for vegetables, 0.63 (P<0.001) for fruits and 0.73 (P<0.001) for fruits and vegetables combined. Cross-classification into quartiles showed that the proportion of participants in the same or the adjacent quartile of the intake distribution were 94% for fruit intake and 80% for vegetable intake. Registered intake of fruits and vegetables was higher the first 4 days of the record than the last 3 days (P=0.002). The 4-day food record correlated with the food frequency questionnaire in similar manner as the 7-day record.

CONCLUSION

The present study indicates that the precoded 24-h recall may be valuable tool for measuring average intake of fruits and vegetables among adults in a population of low intake. Moreover, the food frequency questionnaire was valid for ranking individuals according to their usual intake. A 4-day food record might be sufficient when validating food frequency questionnaires for fruits and vegetables.

Relative validation of a pre-coded food diary among children, under-reporting varies with reporting day and time of the day

OBJECTIVE

The aim of this study was to validate intake of energy, macro- and micronutrients assessed from pre-coded food diaries (PFDs) by using weighed records (WRs) as the reference method among a group of Norwegian 9-year-olds. We also examined how under-reporters (UR) differed from acceptable reporters (AR) according to the energy intake during the 4-day recording period and energy intake distribution during the day.

SUBJECTS AND DESIGN

One hundred 9-year-olds, 45 girls and 55 boys, were recruited to complete a 4-day record with a PFD followed 3 days later with a 4-day WR.

RESULTS

There were no differences between energy and nutrient intake from the two recording methods among boys, but girls reported significantly higher intakes with PFD compared with WR. The median Spearman correlation coefficient between PFD and WR for energy and nutrients was 0.43 for girls and 0.49 for boys. Twelve participants were classified as UR with the PDF method. Energy percentages from macronutrients were not significantly different between UR and AR with the PFD method. UR had significantly lower energy intake in the last two recording days and from 1000 to 2200 hours during the day compared to AR.

CONCLUSIONS

The PFD method is promising as a tool for assessing food intake in large surveys among children. The present study indicates that the PFD gives more valid data for boys than girls according to the group intake and ranking of nutrient intake when WR is the reference method. However, UR seemed to develop a study fatigue during the day and during the recording period. Increased awareness about the tendency of study fatigue can lead to more specific instructions on how participants can handle the problem.

Validation of a pre-coded food diary used among 13-year-olds: comparison of energy intake with energy expenditure

OBJECTIVE

To validate energy intake (EI) estimated from pre-coded food diaries against energy expenditure (EE) measured with a validated position-and-movement monitor (ActiReg) in groups of 13-year-old Norwegian schoolchildren.

DESIGN

Two studies were conducted. In study 1 the monitoring period was 4 days; participants recorded their food intake for four consecutive weekdays using food diaries and wore the ActiReg during the same period. In study 2 the monitoring period was 7 days; participants recorded their food intake for four consecutive days but wore the ActiReg for a whole week.

SETTINGS

Participants were recruited from grade 8 in a school in and one outside Oslo (Norway).

SUBJECTS

Forty-one and 31 participants from study 1 and 2, respectively, completed the study.

RESULTS

The group average EI was 34% lower than the measured EE in study 1 and 24% lower in study 2. The width of the 95% confidence limits of agreement in a Bland-Altman plot for EI and EE varied from -0.2 MJ to 8.2 MJ in study 1 and from -2.3 MJ to 6.9 MJ in study 2. The Pearson correlation coefficients between reported energy intake and expenditure were 0.47 (P=0.002) in study 1 and 0.74 (P<0.001) in study 2.

CONCLUSION

The data showed that there was substantial variability in the accuracy of the food diary at the individual level. Furthermore, the diary underestimated the average energy intake. The ability of the food diary to rank individuals according to energy intake was found to be good in one of the studies and moderate in the other.

Relations between high ponderal index at birth, feeding practices and body mass index in infancy

OBJECTIVE

We compared feeding practices between infants of high ponderal index (PI) at birth (PI above the 90th percentile) and normal PI at birth (PI between 10th and 90th percentiles), and examined how birth size and infant feeding practices were related to body mass index (BMI) at 12 months.

DESIGN

In a cohort of 3000 infants invited to participate in a national Norwegian dietary survey, 1825 participated both at 6 and 12 months of age, and the present study included those born full term and with a PI (weight/length3) at birth > or =10th percentile (n=1441). Data on feeding practices were collected by food-frequency questionnaires, and anthropometrical data were measured by health-care personnel.

RESULTS

A lower proportion of infants born with high PI were exclusively breastfed for at least 4 months compared with infants born with normal PI (37 and 47%, respectively; P=0.03). Earlier introduction of solid foods and higher consumption of some foods were also observed among infants of high PI. In a multivariate analysis, adjusted mean BMI (kg/m2) at 12 months was higher for infants of high PI at birth than for infants of normal PI (17.6 and 17.0, respectively; P<0.001) and higher for infants exclusively breastfed <3 months than for infants exclusively breastfed > or =3 months (17.5 and 17.2, respectively; P=0.001).

CONCLUSIONS

High PI at birth was associated with a shorter duration of exclusive breastfeeding. Furthermore, high PI at birth and short-term exclusive breastfeeding were both associated with higher BMI at 12 months.

Evaluation of the odd fatty acids 15:0 and 17:0 in serum and adipose tissue as markers of intake of milk and dairy fat

BACKGROUND

There is a need for biomarkers of dietary saturated fatty acids, because several diseases have been related to intake of these fatty acids.

OBJECTIVE

To examine the relation between intake of dairy fat and the proportion of pentadecanoic (15:0) and heptadecanoic (17:0) acid in serum and adipose tissue.

DESIGN

Healthy men aged 21-55 y provided serum (n = 110) and adipose tissue samples (n = 107) and completed both 14 days weighed records (WR) and a 180-item food frequency questionnaire (FFQ). The proportions of 15:0 and 17:0 acid in serum and adipose tissue as measured by gas liquid chromatography were evaluated as biomarkers for fat intake from dairy products using Pearsons correlation coefficient and the method of triads.

RESULTS

The strongest correlation coefficients were observed between total intake of dairy fat estimated from WR and relative content of 15:0 in adipose tissue (0.52, 95% CI: 0.37, 0.65) and total serum (0.43, 95% CI 0.26, 0.57). A consistent inverse association was observed between the intake of milk fat and relative serum content of 17:0. The validity coefficients observed for the intake of dairy fat estimated from weighed records, the 180-item FFQ and by the relative content of 15:0 in serum and adipose tissue were 0.94 (95% CI: 0.68, 1.00), 0.50 (95% CI: 0.29, 0.67), 0.49 (95% CI: 0.32, 0.67) and 0.56 (95% CI: 0.28, 0.82), respectively.

CONCLUSION

Relative content of 15:0 in serum and adipose tissue may be a useful biomarker for the intake of total dairy fat, whereas FFQs and WRs may provide better estimates of the intake of fat from milk.

Modulation of COX-2 expression in peripheral blood cells by increased intake of fruit and vegetables?

BACKGROUND

Enhanced cyclooxygenase-2 (COX-2) expression is associated with carcinogenesis, ischemia, angiogenesis, inflammation, and neurodegeneration. The preventing effect of aspirin and nonsteroidal anti-inflammatory drugs is partly due to inhibition of the COX-2 enzyme. Fruit and vegetables (FVs) contain numerous compounds that may decrease disease risk by several different mechanisms, for example through the inhibition of COX-2 activity.

OBJECTIVE

We tested the hypothesis that an increased intake of FVs would modulate the COX-2 expression in peripheral blood cells.

DESIGN

A strictly controlled dietary crossover study (n = 39). After 1 week run-in period with no FVs in the diet, one group was given two portions of FVs (2 FV), while another group was given five portions (5 FV) daily for 14 days. Following a 2 weeks washout period and 1 week run-in, the regimens were switched between the groups. Gene expression analysis of COX-2 mRNA in blood samples was performed by quantitative real-time-PCR.

RESULTS

No significant treatment effect of diet intervention was found in the crossover analyses (P = 0.74). However, the individual variation in response may seem large.

CONCLUSIONS

These data does not contradict the recommendations for an increased intake of FVs. Further studies on expression directly and indirectly, through analysis of factors regulating and being regulated by COX-2, should be carried out. A first step would be to evaluate the correspondence between COX-2 mRNA expression and products of the COX pathway, like prostaglandins. Naturally occurring polymorphisms of COX-2 promoters and coding regions might contribute to functional variations and response to different diets.

SPONSORSHIP

Norwegian Research Council, National Nutrition Council, Throne Holst Foundation for Nutrition Research, Freia Chokoladefabriks Medisinske Fond and the Norwegian Cancer Society.

Can children and adolescents use photographs of food to estimate portion sizes?

OBJECTIVE

The goals of this study were to investigate whether children and adolescents can accurately estimate portion sizes of preweighed food by viewing photographs of food, and whether age influences the ability to estimate food portion sizes.

SUBJECTS

A total of 63 male and female volunteers aged 9-19 y participated in the study.

DESIGN

Each participant received a photographic booklet with photograph series of 13 food items. Participants over 10 y of age were asked to estimate portion sizes of food on 34 plates placed in front of them by comparing the different portions to corresponding photographs of food. Younger participants were asked to estimate portion sizes of food on 17 plates by comparing the portions to photographs.

RESULTS

Participants made 2019 comparisons between actual food portion sizes and photographs of food portion sizes. On average, 60% of the comparisons were made correctly. A photograph directly adjacent to the photograph depicting the correct portion size was chosen in 35% of the comparisons and 5% of the comparisons were made incorrectly. Portion sizes were estimated more accurately when the actual served portions of food had exactly the same appearance as the foods portrayed in the photographic booklet. No differences existed between children's and adolescents' abilities to estimate portion sizes using photographs.

CONCLUSIONS

Large variability may exist in an individual's capability of choosing a photograph that correctly depicts food portion sizes, but the error at the group level is quite small. These data indicate that a photographic booklet of foods can be a useful tool for portion size estimates in these age groups.

SPONSORSHIP

The Norwegian Foundation for Health and Rehabilitation through Norwegian Health Association.

High intake of added sugar among Norwegian children and adolescents

OBJECTIVE

It is debated whether the intake of added sugar displaces micronutrient-rich foods and dilutes the nutrient density of the diet, and whether there is a link between sugar and the increased rate of obesity. The objectives of this study were to examine the effect of added sugar on the intakes of energy, micronutrients, fruit and vegetables, and to examine the association between intake of added sugar and age, sex, body mass index, physical activity, inactivity and parents' education.

DESIGN

Participants recorded their food intake in pre-coded food diaries for 4 days and filled in a questionnaire about physical activity, watching television (TV)/using a personal computer (PC) and parents' education.

SUBJECTS

Three hundred and ninety-one 4-year-olds, 810 students in the 4th grade (9 years old) and 1005 in the 8th grade (13 years old) were included in the study.

RESULTS

The intakes of all nutrients, except alpha-tocopherol among 4-year-olds and vitamin C among 4-year-olds and 4th graders, decreased with increasing content of added sugar in the diet. Moreover, high consumers of added sugar had a 30-40% lower intake of fruit and vegetables than did low consumers. A negative association was observed between consumption of added sugar and body mass index among girls in the 8th grade (P=0.013), whereas a positive association was observed among 4-year-old boys (P=0.055). Associations between physical activity, hours spent watching TV/using a PC, parents' education and the energy intake from added sugar varied in the different age groups.

CONCLUSIONS

This study showed a negative association between the intake of added sugar and intakes of micronutrients, fruit and vegetables. The negative association between sugar intake and intake of fruit and vegetables is important from a public health perspective, since one of the main health messages today is to increase current intake of fruit and vegetables.

Validity and reproducibility of self-reported intake of fruit and vegetable among 6th graders

OBJECTIVE

Reproducible and valid methods for measuring fruit and vegetable consumption among young school children are urgently needed. The aim of this study was to test the reproducibility and the validity of a newly developed questionnaire on the intake of fruit and vegetable among Norwegian 6th graders. The questionnaire consisted of a 24-h recall part and a food frequency part.

DESIGN

A total of 114 pupils completed the questionnaire two times 14 days apart, and another 85 pupils completed the questionnaire and 7-day food diaries.

SUBJECTS

Pupils of 6th grade with a mean age of 11.9 y.

RESULTS

Spearman correlation coefficients between the frequency part of the questionnaire administered two times varied from 0.62 for fruit to 0.83 for potato, and no difference was seen between the average intakes from the two 24-h recalls. The 24-h recall part of the questionnaire gave higher estimates for the average intake of fruit and juice compared to the 7-day record, while no difference was observed for vegetable intake. Spearman correlation coefficients between the frequency part and the records varied from 0.21 for fruit and potato to 0.32 for the total intake of fruit and vegetable.

CONCLUSION

Both the 24-h recall and the frequency part gave a consistent response on separate occasions over the test-retest study period. The 6th graders were capable of recording yesterday's intake of vegetable, but overestimated the intake of fruit and juice. The ability to rank subjects based on the frequency part was rather low.

Six carotenoids in plasma used to assess recommended intake of fruits and vegetables in a controlled feeding study

BACKGROUND

There is a need for objective and universally applicable biomarkers for the intake of foods believed to affect human health.

OBJECTIVE

The purpose of this feeding study was to test whether plasma concentrations of carotenoids could be used to distinguish recommended consumption of mixed fruits and vegetables (five a day) from the current national intake of fruits and vegetables (two a day).

DESIGN

A strict crossover design was chosen to correct for observed interindividual variations in carotenoid response. A total of 40 healthy subjects were included in the study. After 1 week run-in period with no fruits and vegetables in the diet, one group was given two portions (300 g) of fruits and vegetables daily, while another group was given five portions (750 g) for 14 days. Following a 2 week wash-out period and 1 week run-in, the regimens were switched between the groups. Fruits and vegetables were combined to match a typical Norwegian diet.

RESULTS

Enhanced intake from two to five portions of mixed fruits and vegetables increased plasma concentrations of alpha-carotene (P=0.033) and lutein (P=0.051) in a crossover analysis. Analysis of data in the parallel part of the study revealed differences between the high and low intake for plasma concentrations of alpha-carotene (P=0.013) and beta-carotene (P=0.016). A trend was also evident for plasma concentrations of lycopene (P=0.057) and lutein (P=0.076) in the parallel analysis. No effect of high vs low intake of fruits and vegetables was observed for plasma concentrations of beta-cryptoxanthin, zeaxanthin, cholesterol and triacylglycerols.

CONCLUSION

The study indicates that plasma concentration of alpha-carotene, beta-carotene and lutein may be used to assess changes of fruit and vegetable intake corresponding to an increase from the present national intake in Norway to the recommended amount of five portions of fruits and vegetables daily.

SPONSORSHIP

Norwegian Research Council, National Nutrition Council, Throne Holst Foundation for Nutrition Research and Freia Chokoladefabriks Medisinske Fond.

Hormone replacement therapy and hypercoagulability. Results from the Prospective Collaborative Danish Climacteric Study

OBJECTIVE

To assess the influence of a variety of HRT regimens on the haemostatic balance using markers of fibrin turnover and inhibitors of coagulation.

DESIGN

An open randomised study allocating women to either a control group or five different HRT treatment groups.

SETTING

Gentofte Hospital, Hellerup, and Rigshospitalet, Copenhagen, Denmark.

POPULATION

One hundred and forty-nine postmenopausal women without previous venous thromboembolic disease.

METHODS

Prothrombin fragment 1+2 (F(1+2)), fibrin degradation products, antithrombin, protein C, total protein S and activated protein C-normalised ratio were measured at baseline and after 6 and 12 months of HRT in six groups of healthy postmenopausal women: (A). no HRT (reference group), (B). continuous oestradiol valerate (E(2)V) plus cyproterone acetate, (C). cyclic E(2)V plus cyproterone acetate, (D). continuous combined oestrogen (E(2)) plus norethindrone acetate, (E). E(2) combined with local delivery of levonorgestrel and (F). E(2)V plus medroxyprogesterone. HRT-induced changes in the concentration of inhibitors of coagulation and markers of fibrin turnover during 12 months of treatment.

RESULTS

Significant decreases of antithrombin and protein S were found in all treatment groups, of protein C in Groups C, D, E and F and of activated protein C-normalised ratio in Groups E and F. Fibrin degradation products increased after three months of treatment, whereas F(1+2) was persistently increased after three months in Group F. The cumulative response of antithrombin was significantly lower in Groups D, E and F than in the reference group. The cumulative response of protein S and activated protein C-normalised ratio was lower, whereas that of F(1+2) was significantly higher in Group F than in the reference group.

CONCLUSION

HRT reduces the inhibitory potential of coagulation significantly. The effect is related to the type of E(2)/progestin combination administered, but seems to be oestrogen-derived as the most pronounced effect is found with only quarterly progestin intake. Such procoagulant activity of HRT may well translate into clinical manifestations in thrombosis-prone individuals.

Validation of a semi-quantitative food-frequency questionnaire used among 12-month-old Norwegian infants

OBJECTIVE

To assess the validity of a semi-quantitative food-frequency questionnaire (SFFQ) used in a large nation-wide dietary survey among 12-month-old Norwegian infants.

METHODS

The SFFQ was administered to the parents about 1 week before the infants turned 12-month-old. The participants filled in the SFFQ and 1-2 weeks later they kept weighed food records for a total of 7 days. Both methods were completed for 64 infants.

RESULTS

The SFFQ overestimated energy intake with 25% and gave significantly higher estimates of all nutrients compared with the records, except for calcium. Much of the difference between the methods disappeared when nutrient density was compared. Spearman correlation coefficients between pairwise measurements of nutrient intakes from the food records and the SFFQ ranged from 0.18 for vitamin D to 0.72 for polyunsaturated fatty acid intake (median r=0.50). On average 38% of the infants were classified in the same quartile with the two methods, and 3% in the opposite quartile. The correlations for food items varied from 0.28 for sweetened drinks to 0.83 for commercial porridge (median r=0.62).

CONCLUSION

This study indicated that the SFFQ overestimates average absolute nutrient intakes. However, the questionnaire gave better estimates for average nutrient densities than for absolute nutrient intakes. The capability of the questionnaire to rank infants according to intake of nutrients and food items was moderate, but at the same level as others have observed with food-frequency questionnaires.

Infant feeding practices and associated factors in the first six months of life: the Norwegian infant nutrition survey

AIM

To describe and evaluate infant feeding practices during the first 6 mo of life in relation to recommendations, and to study infant feeding practices in relation to maternal and infant characteristics.

METHODS

Data from 2383 Norwegian infants aged 6 mo were collected by a self-administered semi-quantitative food-frequency questionnaire measuring feeding practices at 6 mo and feeding practices retrospectively at < or = 5.5 mo of age.

RESULTS

Only 1% of the infants had never been breastfed. The proportion of breastfed infants was 96% at 1 mo, 85% at 4 mo and 80% at 6 mo. The proportion of exclusively breastfed infants was 90% at 1 mo, 44% at 4 mo and 7% at 6 mo. Twenty-one percent of the infants were introduced to solid foods before the age of 4 mo. For exclusive breastfeeding at 4 mo, breastfeeding at 6 mo and timely introduction of solid foods (not before 4 mo) significant positive trends were found for maternal age, education and degree of urbanization. Negative associations were found for maternal smoking. Furthermore, exclusive breastfeeding at 4 mo was associated with infant gender and marital status, and the odds of breastfeeding at 6 mo significantly decreased with decreasing infant birthweight. Finally, both the odds of exclusive breastfeeding at 4 mo and of breastfeeding at 6 mo increased with increasing numbers of children.

CONCLUSION

These results indicate that a majority of Norwegian infants are fed in accordance with infant feeding recommendations during their first 6mo of life. However, the duration of exclusive breastfeeding is shorter than recommended. Infant feeding practices are significantly associated with maternal and infant characteristics.

Effects of different progestin regimens in hormone replacement therapy on blood coagulation factor VII and tissue factor pathway inhibitor

BACKGROUND

Long-term hormone replacement therapy (HRT) reduces cardiovascular risk, but an early increased risk was reported in women with coronary heart disease. In such women the arterial intima can express tissue factor, and changes in coagulation factor VII (factor VII) and tissue factor pathway inhibitor (TFPI) may be deleterious.

METHODS

We measured factor VII clotting activity, activated factor VII, and concentrations of factor VII and TFPI during 12 months in healthy post-menopausal women randomized to: (i). cyclic oral estrogen/progestin (n = 25); (ii). long-cycle oral estrogen/quarterly progestin (n = 32); (iii). continuous oral estrogen/progestin (n = 21); (iv). continuous oral estrogen/intrauterine progestin (n = 22); (v). no HRT (n = 26). Blood was collected at baseline, 3, 6 and 12 months. Additional sampling was done before progestin intake in the long cycle group.

RESULTS

No variations were observed in the reference group. There was a substantial decrease in TFPI concentrations in the HRT groups irrespective of the type of progestin. In women receiving long-cycle treatment, all factor VII measures increased during the unopposed estrogen periods, and the increase was reversed after progestin intake. The integrated response, AUC, for TFPI was significantly lower in the HRT groups compared with the reference group.

CONCLUSION

The observed changes may increase the early thrombotic risk associated with HRT use.

Usefulness of a short food frequency questionnaire for screening of low intake of fruit and vegetable and for intake of fat

BACKGROUND

Simple screening tools to identify intake of fruit, vegetables and fat are necessary to design effective public health intervention strategies in order to increase intake of fruit and vegetable and to reduce fat intake.

METHODS

108 men recorded their food intake for 14 days and filled in a 27-item food frequency questionnaire (FFQ) 1.5-2 months later. Estimates of fruit, vegetables and fat intake from the FFQ were compared with those from the weighed records.

RESULTS

Mean intake of vegetables and fruit estimated from the diet records increased with increasing categories for frequency of intake assessed by the FFQ. Spearman correlation coefficient between frequency of intake of vegetables and fruit from the FFQ and amount of these food items estimated from the weighed records was 0.46 and 0.66, respectively. The ability of the FFQ to predict those having inadequate intake of fruits and vegetables based on weighed record data, was more than 90%. Almost 95% who reported use of fat spreads by the FFQ also reported this by the records. The correlation coefficient between the amount of fat used on bread from the two methods was 0.79. The correlation between fat intake estimated from both methods was 0.36 and for saturated fat intake the correlation was 0.38.

CONCLUSION

The FFQ could be used to screen for low consumers of fruit, vegetable and fat spread in intervention programmes. However, the ability of the FFQ to identify persons with high (or low) intake of fat and saturated fat was not good.

Metabolic and fibrinolytic response to changed insulin sensitivity in users of oral contraceptives

The fundamental role of insulin resistance for metabolic changes linked to cardiovascular disease and type 2 diabetes is increasingly recognized. Oral contraceptives (OC) may affect insulin sensitivity, and a detailed characterization hereof, as well as the secondary effects on related metabolic systems, are relevant in the evaluation of the risk of developing vascular disorders or diabetes in OC users. We studied insulin sensitivity index (S(I)), glucose effectiveness (S(g)), and insulin response in young, healthy women by frequently sampled intravenous glucose tolerance tests before and after randomization to 6 months of treatment with ethinyl estradiol in triphasic combination with norgestimate (n = 17) or gestodene (n = 20). Measurements of fasting triglycerides and antigen concentrations of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAI-1) were also included. Both compounds increased fasting plasma insulin and reduced S(i) but did not affect S(g). The relationships between S(i) and insulin response were unchanged. No consistent correlation between insulin sensitivity and triglycerides, t-PA, or PAI-1 were demonstrated before or during treatment. We conclude that the treatments were followed by a compensated decrease in insulin sensitivity that was unrelated to changes in triglycerides, t-PA, or PAI-1 antigen.

[Biological markers for the intake of fruit and vegetables]

No available dietary assessment method is without error in measuring dietary intake. This has led to an increased interest in biological markers of dietary intake. This article is a review of the literature investigating whether the concentration of carotenoids in blood can serve as biological markers for the intake of fruit and vegetables. The literature indicates an association between intake of fruit and vegetables and the concentration of total carotenoids, alfa-carotene, beta-carotene, lutein and beta-cryptoxanthin in plasma. The same association was not observed for plasma lycopene. Results from several studies also indicate that plasma alfa-carotene and plasma total carotenoids are more suitable as biological markers of the intake of fruit and vegetables than the other carotenoids. As there are large individual variations in the plasma carotenoid response after intake, carotenoids in blood will be a better marker of intake at group level than individual level. Furthermore, the average value from several measurements of carotenoids in blood will be a better marker of long-term intake than a single measurement. Several factors in addition to fruit and vegetables influence the concentration of carotenoids in blood. It is important to assess these factors when carotenoids in blood are used as biological markers of the intake of fruit and vegetables.

Evaluation of a food frequency questionnaire with weighed records, fatty acids, and alpha-tocopherol in adipose tissue and serum

The authors examined the validity of a self-administered 180-item food frequency questionnaire in 125 Norwegian men aged 20-55 years who filled in the questionnaire and completed 14-day weighed records in fall 1995 to winter 1995/6. Spearman correlation coefficients between the two measurements ranged from 0.42 for percent of energy from fat to 0.66 for sugar intake (median r = 0.51). On average, 39% of the men were classified in the same quartile with the two methods, and 3% in the opposite quartile. Correlation coefficients between intake of fatty acids estimated from the questionnaire and the relative amounts of fatty acids in adipose tissue were: linoleic acid (18:2, n-6), r = 0.38; alpha-linolenic acid (18:3, n-3), r = 0.42; eicosapentaenoic acid (20:5, n-3), r = 0.52; and docosahexaenoic acid (22:6, n-3), r = 0.49. The correlations for these fatty acids between the total serum lipids and the diet were 0.16, 0.28, 0.51 and 0.52, respectively. The data suggest that very-long-chain n-3 fatty acids in adipose tissue and total serum lipids reflect the dietary intake of very-long-chain n-3 fatty acids to the same degree. No associations were observed between intake of alpha-tocopherol and concentration in adipose tissue and serum.

Effects of hormone replacement therapy on hemostatic cardiovascular risk factors

OBJECTIVES

From observational studies, there is evidence that hormone replacement therapy in postmenopausal women causes a decrease in cardiovascular events. It remains unknown, however, precisely by which mechanisms this reduction is achieved. The primary aim of this work was to study the effects of hormone replacement therapy on established hemostatic risk factors during 1-year treatment of healthy postmenopausal women. The secondary aim was to investigate whether there was any significant difference in these risk factors between hormone replacement therapy administered as a cyclic estrogen/sequential progestogen or continuous estrogen/sequential progestogen regimen.

STUDY DESIGN

Sixty postmenopausal women were randomized to treatment with estradiol valerate 2 mg/day either continuously or cyclic (days 1 to 21; placebo on days 21 to 28). Both groups received cyproterone acetate 1 mg/day on days 12 to 21. Blood samples were collected before treatment and on cycle days 17 to 22 in cycles 3, 6, and 12. Thirty women with basic characteristics identical to the women included in the treatment group were included as a reference group. Blood samples were collected after 0, 6, and 12 months of observation.

RESULTS

Hormone replacement therapy during 1 year caused a marginal but significant increase in plasma concentration of factor VIIc after 12 months of treatment (P <.05), a significant decrease in fibrinogen, and a significant decrease in the protein concentrations of tissue-type plasminogen activator, plasminogen activator inhibitor-1, and lipoprotein(a) after 3, 6, and 12 months of treatment (P <.05). Possible differences in the integrated response between the reference group and the hormone replacement therapy group were evaluated by comparison of the area under the curve as estimated in each individual on the basis of each analyte in the sampling periods. The area under the curve of fibrinogen was significantly lower in the hormone replacement therapy group than in the reference group (P <.03), whereas other variables did not deviate significantly between the groups. The areas under the curve did not deviate significantly between the group that received cyclic estrogen/sequential progestogen and the group that received continuous estrogen/sequential progestogen.

CONCLUSIONS

One-year treatment with hormone replacement therapy influenced favorably a number of prognostic cardiovascular risk factors in healthy women. The most important effect was the lowering of fibrinogen. Furthermore, in this study the effect of hormone replacement therapy on hemostasis did not deviate between a cyclic estrogen/sequential progestogen regimen and a continuous estrogen/sequential progestogen regimen.

[Measures to promote healthy dietary habits among schoolchildren]

The Norwegian National Nutrition Council has, over the past years, implemented a number of measures designed specifically to promote well-organized school meals and increase the consumption of fruit and vegetables among school children. These measures include the development of national guidelines for organizing school meals, economic support for trying out new methods of operating a school cafeteria, national campaigns to promote the traditional Norwegian packed lunch, open community meetings with political and administrative leaders at municipality level, the introduction of a system whereby pupils can purchase fresh fruit and vegetables at school, and advocacy through mass media. Results of an ongoing evaluation seem to indicate that these measures have had a positive effect on the organization of school meals. More young children are attended to by an adult during mealtimes, more pupils are allowed at least 20 minutes for their lunch break, and a growing number of secondary schools are introducing school cafeterias. However, only half of the total number of schools seem to be aware of the new guidelines, and much more work is required in order to ensure all students are provided with a well-organized school meal. Health personnel play a critical role in ensuring that this work is given political priority, also at the local level.

Thermal balloon endometrial ablation: safety aspects evaluated by serosal temperature, light microscopy and electron microscopy

OBJECTIVES

Thermal balloon endometrial ablation is a new method for treating menorrhagia. The technique appears to be less difficult compared to standard hysteroscopic ablation techniques and to be significantly safer. The influence into the uterine wall of the thermal balloon ablation procedure was investigated with special reference to the ability of total destruction of the endometrium and the thermal action on the myometrium and the serosa.

STUDY DESIGN

Temperatures were measured at the uterine serosal surface during thermal balloon endometrial ablation for 8-16 min in eight patients. After subsequent hysterectomy the extent of thermal damage into the myometrium was assessed by light and electron microscopy.

RESULTS

The highest temperature measured on the uterine serosa was 39.1 degrees C. Coagulation of the myometrium adjacent to the endometrium could be demonstrated by light microscopy in all patients, with a maximum depth of 11.5 mm. By electron microscopy no influence of heat could be demonstrated beyond 15 mm from the endometrial surface.

CONCLUSION

Up to 16 min of thermal balloon endometrial ablation therapy can destroy the endometrium and the submucosal layers. The myometrium is only coagulated to a depth where full thickness necrosis or injury is unlikely.

Ampicillin-metronidazole treatment in idiopathic preterm labour: a randomised controlled multicentre trial

OBJECTIVE

To determine whether treatment with ampicillin and metronidazole in women with threatened idiopathic preterm labour will prolong the gestation and reduce maternal and neonatal infectious morbidity.

DESIGN

Randomised controlled double-blind trial.

SETTING

Six obstetric departments in the Copenhagen area.

POPULATION

One hundred and twelve women with singleton pregnancies, with threatened idiopathic preterm labour and intact amniotic membranes at 26 to 34 weeks of gestation.

METHODS

Random allocation to eight days intravenous and oral treatment with ampicillin and metronidazole, or placebo.

MAIN OUTCOME MEASURES

Number of days from admission to delivery, gestational age at delivery, rates of preterm delivery, low birthweight, maternal infections and neonatal infections.

RESULTS

Treatment with ampicillin and metronidazole was associated with a significant prolongation of pregnancy (admission to delivery 47.5 days versus 27 days, P < 0.05), higher gestational age at delivery (37 weeks versus 34 weeks, P < 0.05), decreased incidence of preterm birth (42% versus 65%, P < 0.05), and lower rate of admission to neonatal intensive care unit (40% versus 63%, P < 0.05), when compared with placebo treatment. Antibiotic treatment had no significant effects on infectious morbidity.

CONCLUSIONS

Treatment with ampicillin and metronidazole in women with threatened idiopathic preterm labour significantly prolonged the gestation, but had no effects on maternal and neonatal infectious morbidity.

Very-long-chain n-3 fatty acids as biomarkers for intake of fish and n-3 fatty acid concentrates

We examined how supplementation with very-long-chain n-3 fatty acids was reflected in the concentration of these fatty acids in plasma phospholipids of 363 Norwegian men and women. The concentration of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in plasma phospholipids was significantly higher among individuals supplemented with n-3 fatty acids after the supplementation period than before. We also examined the relation between dietary intake of fatty acids measured with a 180-item quantitative food-frequency questionnaire and the concentration of the same fatty acids in plasma phospholipids in 579 men and women. Correlation coefficients between plasma phospholipid fatty acids and dietary intake of fatty acids were 0.51 and 0.49 for EPA and DHA, respectively. The correlation between fish intake and n-3 fatty acids in plasma phospholipids was 0.37. These results suggest that dietary intake measured with our food-frequency questionnaire may be used to predict the biological availability of some of the essential n-3 fatty acids.

No influence of proinsulin and insulin on plasma levels of plasminogen activator inhibitor type 1 and tissue plasminogen activator in young women before and during intake of contraceptive steroids

Clinical observations in patients predisposed to cardiovascular disorders and recent experimental observations suggest that proinsulin and insulin participate in the regulation of fibrinolysis in vivo. In the present study, we examined if proinsulin and insulin affect the constitutive (fasting) secretion of plasminogen activator inhibitor type 1 (PAI-1) and tissue plasminogen activator (t-PA) in young healthy women (N = 17). We also measured the antigen concentrations of PAI-1 and t-PA during slow and fast changes in proinsulin and insulin levels induced by oral (OGTT) and intravenous (IVGTT) glucose tolerance tests. The assessments were performed before and after 6 months of treatment with contraceptive steroids, which have a well-defined influence on the fibrinolytic variables. We observed no consistent correlations between fasting values of proinsulin, insulin, PAI-1, and t-PA either before or during hormonal treatment. Before hormonal treatment, PAI-1 and t-PA antigen levels decreased (P < .05) during the hyperproinsulinemia and hyperinsulinemia induced by the OGTT and IVGTT. After hormonal intake for 6 months, a decrease only in t-PA concentrations during the OGTT was observed despite similar proinsulin and insulin responses to the glucose loads. Our findings suggest that proinsulin and insulin have no influence on the regulation of plasma levels of PAI-1 and t-PA in young healthy women, irrespective of intake of contraceptive steroids.

Dietary intake among Norwegian adolescents

OBJECTIVE

The aim of the nationwide study on dietary behaviour of adolescents was to describe and evaluate dietary habits, and relate that to other lifestyle factors. DESIGN AND SUBJECT: 1564 students in secondary schools completed a self-administered quantitative food frequency questionnaire in a school setting.

RESULTS

The questionnaire showed an average energy intake of 15.8 and 9.9 MJ among boys and girls, respectively. Nearly 31% of the energy was supplied by fat and 11.4% by sugar. The average daily intake of micronutrients exceeded the Norwegian recommendations, except for vitamin D and iron in girls. 13.4% of the students had breakfast twice a week or less. These students had a higher percentage of energy from fat and sugar, and a lower intake of micronutrients, than students eating breakfast more often. Students who were daily smokers or fairly inactive had higher energy percentage from fat and sugar and lower intake of fibre, than non-smokers or physically active students.

CONCLUSION

Half of the students consumed a diet with too much fat and two-thirds consumed too much sugar as compared to the recommendations. The girls had a diet with a higher nutrient density and a lower fat energy percentage than the boys. Finally, it seemed as if a healthy lifestyle was associated with a healthy diet.

Evaluation of a quantitative food frequency questionnaire used in a group of Norwegian adolescents

OBJECTIVE

The study was conducted to assess the reproducibility and validity of a 190-item self-administered quantitative food frequency questionnaire, used in a nation-wide study of adolescents.

DESIGN AND SUBJECTS

Reproducibility study; 103 11th grade students (18 years) completed the questionnaire twice, with a 6-week interval. Validation study; 49 11th grade students filled in the questionnaire and kept 7-day weighed food records.

RESULTS

Spearman rank correlations between the nutrient intakes from the two questionnaires varied from 0.63 (sugar energy percentage) to 0.91 (alcohol). The median coefficient was 0.85. The first questionnaire produced generally higher nutrient intake estimates than the second. Correlations between nutrient intake values from the records and the questionnaire ranged from 0.14 (vitamin D, non-significant, cod liver oil not included) to 0.66 (monounsaturated fatty acids). The median coefficient was 0.52. Adjustment for energy intake did not materially affect the correlations. On average 41% of the subjects were classified in the same quartile in the questionnaire and the records, and 2% in the opposite quartiles. However, the percentage of subjects in the same/opposite quartiles for vitamin D and fibre were 33/12 and 22/6, respectively.

CONCLUSIONS

It is concluded that the questionnaire is able to rank subjects according to the tested nutrients, except vitamin D and fibre.

Effects of the non-peptide inhibitor OPC-21268 on oxytocin and vasopressin stimulation of rat and human myometrium

OPC-21268 (1-[-1-[4-(3-acetylaminopropoxy)benzoyl]-piperidyl]-3,4- dihydro-2(1H)-quinolinone), a non-peptide vasopressin V1 receptor antagonist, inhibited oxytocin- and vasopressin-induced contractions of myometrial strips from rats and from full-term pregnant women. Administered intravenously in rats the drug also inhibited uterine contractions caused by infusion of oxytocin. When incubated with purified plasma membranes from rat or human myometrial tissue, OPC-21268 inhibited the specific receptor binding of tritiated oxytocin and vasopressin in a dose-dependent and reversible way.

Uro-genital microbial colonization and threatening preterm delivery

OBJECTIVE

To examine whether there is a relationship between the uro-genital microbial colonization and threatening preterm delivery.

STUDY DESIGN

The microflora in the urine and endocervix was studied in 43 women with preterm labor, 45 women with preterm premature rupture of the membranes (PPROM) and 80 normal pregnant women at 26-34 weeks of gestation. Amniotic fluid was examined in 20 of the patients with preterm labor. Data were analyzed by Fisher's exact test (two-tailed).

RESULTS

The microflora in the urine was not significantly different in patients with preterm labor, PPROM and normal pregnant women. Compared with normal pregnant women, patients with preterm labor had significantly lower prevalences of corynebacteria (p < 0.05) and coagulase-negative staphylococci (p < 0.01) in the cervix, while patients with PPROM had significantly lower prevalences of lactobacilli (p < 0.05) and coagulase-negative staphylococci (p < 0.05) in the cervix. Positive amniotic fluid cultures were detected in three of the 20 patients with preterm labor who underwent transabdominal amniocentesis. Evidence of ascending colonization was found in two of these cases.

CONCLUSIONS

The microbial colonization of the urine was not associated with threatening preterm delivery. Reduced prevalences of lactobacilli, corynebacteria and coagulase-negative staphylococci in the cervix were associated with threatening preterm delivery.

[Relation between cervical conization, microbial colonization and threatening preterm labor]

The relationship between prior cervical conization, the cervical microbial colonization and threatening preterm delivery was investigated in 35 women with preterm premature rupture of the membranes (PPROM), 38 women with idiopathic preterm labor and 75 normal pregnant women at 26-34 weeks of gestation. Prior cervical conization occurred with a significantly higher frequency in PPROM patients than in patients with preterm labor (p < 0.01) and normal pregnant women (p < 0.001). The prevalence of lactobacilli was lower in patients with PPROM than in patients with preterm labor (p < 0.05) and control patients (p = 0.05)--and lower in patients with prior cervical conization than in patients without prior conization (p < 0.05). All other microorganisms occurred with the same frequencies in all groups.

CONCLUSIONS

Prior conization was associated with PPROM. Women with prior conization and women with PPROM had a reduced prevalence of lactobacilli in the cervix. The "absence" of lactobacilli may indicate changes in the cervical microflora, which could be of importance for PPROM.