Intake of vitamin D by Finnish children aged 3 months to 3 years in relation to sociodemographic factors.

OBJECTIVE: To study the total daily intake of vitamin D from food and supplements among Finnish children aged 3 months to 3 years, the dietary sources of vitamin D and the association between vitamin D intake and sociodemographic factors. SUBJECTS AND METHODS: The subjects are participants in the Finnish Type I Diabetes Prediction and Prevention Nutrition Study born between October 1997 and October 1998. At the age of 3 and 6 months, 1, 2 and 3 years, 342 (72% of the invited families), 298 (63%), 267 (56%), 233 (49%) and 209 (44%) families, respectively, participated in the present study. Food consumption was assessed by a 3-day food record. A structured questionnaire was used to record the parents' socioeconomic status. RESULTS: The mean dietary vitamin D intake exceeded the recommendation (10 microg/day) at the age of 3 (11.0 microg) and 6 months (12.0 microg), but decreased thereafter being 9.8, 5.0 and 4.1 microg at 1, 2 and 3 years of age, respectively. Among the children 91, 91, 81, 42 and 26% used vitamin D supplements at the age of 3 and 6 months, and 1, 2 and 3 years, respectively. In children not using vitamin D supplements, vitamin D intake was less than 10 microg/day at all ages. Vitamin D intake from food did not differ in children who used and did not use vitamin D supplements. Vitamin D supplements were the main source of vitamin D intake in all age groups studied, followed by vitamin D-fortified infant formula in 3-month-olds and infant formula and baby foods in 6-month-olds. After the age of 1 year, the most important food sources of vitamin D were margarine, fish, baby foods, low-fat milk and eggs. Sociodemographic factors, especially the number of children in the family and maternal age, were associated with the total vitamin D intake and vitamin D supplement use. CONCLUSION: Vitamin D supplements are not used according to the dietary recommendations in a substantial proportion of Finnish children.

Age at introduction of new foods and advanced beta cell autoimmunity in young children with HLA-conferred susceptibility to type 1 diabetes.

AIMS/HYPOTHESIS: Evidence for the role of infant feeding in the development of beta cell autoimmunity is inconsistent. We set out to study the effects of breastfeeding and of age at introduction of supplementary foods on the development of beta cell autoimmunity. SUBJECTS AND METHODS: A prospective birth cohort of 3,565 infants with HLA-DQB1-conferred susceptibility to type 1 diabetes was recruited between 1996 and 2001 from two university hospital areas in Finland. Blood samples were collected at 3- to 12-month intervals to measure antibodies against islet cells, insulin, glutamate dehydroxylase and islet antigen 2. The families kept a record on the age at introduction of new foods, and for each visit completed a structured dietary questionnaire. The endpoint was repeated positivity for islet cell antibodies together with at least one of the other three antibodies. RESULTS: The overall or exclusive duration of breastfeeding was not associated with the risk of developing the endpoint. An early age at introduction of fruits and berries (< or =4 months) was related to increased risk of developing positivity for the endpoint (hazard ratio [95% CI] for earliest tertile 2.02 [1.03-3.95] and for midtertile 1.97 [1.06-3.64] compared with latest tertile >4 months). Also, introducing roots between 3 and 3.9 months (midtertile) was related to increased risk of the endpoint (hazard ratio [95% CI] for the earliest tertile 1.04 [0.57-1.90] and for midtertile 1.82 [1.19-2.79] compared with latest tertile). These associations were independent of several putative socio-demographic and perinatal confounding factors. CONCLUSIONS/INTERPRETATION: Our findings suggest that an early age at introduction of fruits and berries and roots associates independently with beta cell autoimmunity, contradicting earlier findings from smaller birth cohort studies.

Health inequality in adolescence. Does stratification occur by familial social background, family affluence, or personal social position?

BACKGROUND: Two new sets of stratification indicators--family's material affluence and adolescent's personal social position- were compared with traditional indicators of familial social position based on parental occupation and education for their ability to detect health inequality among adolescents. METHODS: Survey data were collected in the Adolescent Health and Lifestyle Survey in 2003 from nationally representative samples of 12-, 14- and 16-year-old Finns (number of respondents 5394, response rate 71%). Indicators of the familial social position were father's socio-economic status, parents' education, parents' labour market position. Indicators of material affluence were number of cars, vacation travels, and computers in the family, own room and amount of weekly spending money. Adolescent's personal social position was measured as school performance. Measures of health were long-standing illness, overweight, use of mental health services, poor self-rated health and number of weekly health complaints. Ordinal logistic regression analysis was applied to study the associations between stratification indicators and health variables. RESULTS: All three groups of indicators of social stratification showed inequality in health, but the strongest associations were observed with the adolescent's personal social position. Health inequality was only partly identifiable by the traditional indicators of familial social position. The direction of the inequality was as expected when using the traditional indicators or personal social position: adolescents from higher social positions were healthier than those from lower positions. The indicators of family's material affluence showed mainly weak or no association with health and some of the indicators were inversely associated, although weakly. CONCLUSION: In addition to traditional indicators describing the socio-structural influences on the distribution of health among adolescents, indicators of family's material affluence should be further developed. Adolescents' personal social position should be included in the studies of health inequalities.

Use of information and communication technology and prevalence of overweight and obesity among adolescents.

BACKGROUND: The prevalence of overweight and obesity has increased among children and adolescents, as well as among adults, and television viewing has been suggested as one cause. Playing digital games (video, computer and console games), or using computer may be other sedentary behaviors related to the development of overweight and obesity. OBJECTIVE: To study the relationships of times spent on viewing television, playing digital games and using computer to overweight among Finnish adolescents. DESIGN: Mailed cross-sectional survey. SUBJECTS: Nationally representative samples of 14-, 16-, and 18-y-old (N=6515, response rate 70%) in 2001. METHODS: Overweight and obesity were assessed by body mass index (BMI). The respondents reported times spent daily on viewing television, playing digital games (video, computer and console games) and using computer (for e-mail, writing and surfing). Data on timing of biological maturation, intensity of weekly physical activity and family's socio economic status were taken into account in the statistical analyses. RESULTS: Increased times spent on viewing television and using computer were associated with increased prevalence of overweight (obesity inclusive) among girls: compared to girls viewing television <1 h daily, the adjusted odds ratio (OR) for being overweight was 1.4 when spending 1-3 h, and 2.0 when spending > or =4 h daily on viewing television. In girls using computer > or =1 h daily, the OR for being overweight was 1.5 compared to girls using computer <1 h daily. The results were similar in boys, although not statistically significant. Time spent on playing digital games was not associated with overweight. CONCLUSION: Overweight was associated with using information and communication technology (ICT), but only with certain forms of ICT. Increased use of ICT may be one factor explaining the increased prevalence of overweight and obesity at the population level, at least in girls. Playing digital games was not related to overweight, perhaps by virtue of game playing being less sedentary or related to a different lifestyle than viewing television and using computer.

Secular trends in overweight and obesity among Finnish adolescents in 1977-1999.

OBJECTIVE: To study the trends in overweight and obesity among Finnish adolescents in 1977-1999. DESIGN: Mailed surveys every other year. SUBJECTS: Nationally representative samples of 12, 14, 16 and 18-y-olds (n = 64,147, response rate 78.9%). METHODS: Overweight and obesity were measured by body mass index (BMI) and relative weight (RW) based on self-reported height and weight. BMI > or = the 85th percentile cut-off point for BMI in each age- and sex-specific group in the entire data set was considered as overweight, and BMI > or = 95th percentile cut-off point as obesity. RW > or = 110% and > or = 120%, calculated as the individual's weight divided by the mean weight in each age- and sex-specific height percentile group in the entire data set, were considered as overweight and obesity, respectively. The trends in overweight and obesity are described by the change in the 85th and 95th percentile cut-off points of BMI over time. The prevalence of overweight and obesity is also reported using BMI reference values recommended for international comparisons. Because of the similarity of the BMI and the RW criteria in classifying adolescents as overweight and obese, only results based on BMI are presented. RESULTS: Overweight and obesity increased linearly in all sex and age groups from 1977 to 1999. Depending on the age group, the average increase in the 85th percentile cut-off point of the BMI per 10 y was 0.6-1.1 kg/m2 in boys and 0.3-0.7 kg/m2 in girls. The 95th percentile cut-off point of the BMI for boys and girls increased by 1.1-1.6 kg/m2 and by 0.6-1.0 kg/m2 per 10 y, respectively. In boys, the increase in overweight and obesity was largest in the two youngest age groups. In girls, the increase in overweight was largest in the oldest age group, and that of obesity both in the 14 and 18-y-olds. Overweight and obesity increased more in boys than in girls in all age groups except in the 18-y-olds among whom the increase was similar in both sexes. Examination of the entire BMI distribution showed that there was little or no change over time at the lower (5th, 15th) and middle (50th) percentiles, but increasing differences at the upper end of the distribution, the increases in the 95th percentile being even more marked than those in the 85th percentile curves. According to international reference values, the age-standardized prevalence of overweight increased in boys from 7.2 to 16.7%, and in girls from 4.0 to 9.8%, between 1977 and 1999. The prevalence of obesity in boys was 1.1% in 1977 and 2.7% in 1999, and in girls 0.4 and 1.4%, respectively. CONCLUSION: Overweight and obesity increased remarkably among Finnish adolescents from 1977 to 1999. The changes concentrated at the upper end of the BMI distribution, suggesting that factors behind this development have influenced only a part of the adolescent population.

Pharmacokinetics of bisphosphonates in rabbits.

Clodronate, pamidronate and etidronate are commonly used bisphosphonates, which accumulate extensively in arteries and some other tissues. We compared their pharmacokinetics in rabbits with those of tiludronate, the drug newly introduced to clinical use. The 14C-labelled drugs were given intravenously and plasma drug levels were monitored for up to 24 hr. The dose-related plasma concentrations of tiludronate and etidronate were clearly higher and decreased more slowly than those of clodronate and pamidronate (P < 0.001). Already at 5 min., the concentrations of tiludronate and etidronate were higher than those of clodronate and pamidronate (P = 0.016). At 24 hr, plasma concentration of tiludronate was 12 +/- 6.6%, of etidronate 18 +/- 2.5%, of clodronate 0.8 +/- 0.2%, and of pamidronate 1.4 +/- 0.4% of the dose per body weight. With the same dose (25 mg/kg), absolute AUC0-24 hr for tiludronate and etidronate was 9-11 times larger than for clodronate. AUC0-24 hr for pamidronate (2.5 mg/kg) was 11% of that for clodronate. Plasma clearance of tiludronate and etidronate was 9-15 times slower than that of clodronate and pamidronate. At 24 hr, the mean tissue-to-plasma ratio of tiludronate for aorta was 1.2-1.6. For bone, spleen, liver and kidneys the ratio varied from 5.4 to 52.6. The results suggest that 1) tiludronate and etidronate are removed from plasma much slower than clodronate and pamidronate, and 2) the potential of tiludronate to concentrate in arteries and bone is generally smaller than previously found with the other bisphosphonates.

Transformation of bisphosphonates into insoluble material in human blood in vitro.

The aim of the study was to find out whether bisphosphonates transform into insoluble material in human blood and serum in vitro. Samples of fresh blood and serum were incubated with various concentrations of 14C-labelled clodronate, etidronate, pamidronate and tiludronate for 2 h and 8 h at 37 degrees C. The presence of unfiltrable material in the plasma separated from the blood, and in the serum were studied with 1) 100, 300 and 1,000 kd (kilo Daltons) filter tubes centrifuged at 3,000 g for 60 min, and 2) high-speed centrifugation at 13,000 g for 30 min. The radioactivities in the ultrafiltrates and supernatants were compared to those in the native plasma or serum. All bisphosphonates transformed into unfiltrable material, which was separated from the samples with the 100 and 300 kd filters but not with the 1,000 kd filter. The material was not sedimented with the high-speed centrifugation. The lengthening of the incubation time from 2 h to 8 h increased the unfiltrable fraction, which generally was dependent on the drug concentration in the blood, too. However, the fraction of the unfiltrable material did not seem to increase with time when the drug was incubated with serum instead of blood. Since drug binding to plasma proteins is generally a very rapid process, some factors other than proteins only, e.g. cations or cation residues, present in the blood but not in the serum, should be involved in transforming of bisphosphonates into insoluble material in the blood.