Suvi M. Virtanen

Intake of vitamin D and risk of type 1 diabetes: a birth-cohort study

BACKGROUND Dietary vitamin D supplementation is associated with reduced risk of type 1 diabetes in animals. Our aim was to ascertain whether or not vitamin D supplementation or deficiency in infancy could affect development of type 1 diabetes. METHODS A birth-cohort study was done, in which all pregnant women (n=12055) in Oulu and Lapland, northern Finland, who were due to give birth in 1966 were enrolled. Data was collected in the first year of life about frequency and dose of vitamin D supplementation and presence of suspected rickets. Our primary outcome measure was diagnosis of type 1 diabetes by end of December, 1997. FINDINGS 12058 of 12231 represented live births, and 10821 (91% of those alive) children were followed-up at age 1 year. Of the 10366 children included in analyses, 81 were diagnosed with diabetes during the study. Vitamin D supplementation was associated with a decreased frequency of type 1 diabetes when adjusted for neonatal, anthropometric, and social characteristics (rate ratio [RR] for regular vs no supplementation 0.12, 95% CI 0.03-0.51, and irregular vs no supplementation 0.16, 0.04-0.74. Children who regularly took the recommended dose of vitamin D (2000 IU daily) had a RR of 0.22 (0.05-0.89) compared with those who regularly received less than the recommended amount. Children suspected of having rickets during the first year of life had a RR of 3.0 (1.0-9.0) compared with those without such a suspicion. INTERPRETATION Dietary vitamin D supplementation is associated with reduced risk of type 1 diabetes. Ensuring adequate vitamin D supplementation for infants could help to reverse the increasing trend in the incidence of type 1 diabetes.

Dietary factors determining diabetes and impaired glucose tolerance. A 20-year follow-up of the Finnish and Dutch cohorts of the seven countries study.

OBJECTIVE To investigate the role of diet as a predictor of glucose intolerance and non-insulin-dependent diabetes mellitus (NIDDM). RESEARCH DESIGN AND METHODS At the 30-year follow-up survey of the Dutch and Finnish cohorts of the Seven Countries Study, in 1989/1990, men were examined according to a standardized protocol including a 2-h oral glucose tolerance test. Information on habitual food consumption was obtained using the cross-check dietary history method. Those 338 men in whom information on habitual diet was also available 20 years earlier were included in this study. Subjects known as having diabetes in 1989/1990 were excluded from the analyses. RESULTS Adjusting for age and cohort, the intake of total, saturated, and monounsaturated fatty acids and dietary cholesterol 20 years before diagnosis was higher in men with newly diagnosed diabetes in the survey than in men with normal or impaired glucose tolerance. After adjustment for cohort, age, past body mass index, and past energy intake, the past intake of total fat was positively associated with 2-h postload glucose level (P < 0.05). An independent inverse association with the past intake of vitamin C was observed (P < 0.05). These associations were independent of changes in the intake of fat and vitamin C during the 20-year follow-up. An increase in the consumption of vegetables and legumes, potatoes, and fish during the 20-year follow-up was inversely related with 2-h glucose level (P < 0.05). CONCLUSIONS Although the regression coefficients were in general not very large, these results indicate that a high intake of fat, especially that of saturated fatty acids, contributes to the risk of glucose intolerance and NIDDM. Foods such as fish, potatoes, vegetables, and legumes may have a protective effect. In addition, the observed inverse association between vitamin C and glucose intolerance suggests that antioxidants may also play a role in the development of derangements in glucose metabolism.

Maternal vitamin D intake during pregnancy is inversely associated with asthma and allergic rhinitis in 5‐year‐old children

Background Vitamin D is known to have a number of immunological effects and it may play a role in preventing allergic diseases.

Back, neck, and shoulder pain in Finnish adolescents: national cross sectional surveys

Abstract Objectives: To study changes in pain of the back and neck in adolescents between 1985 and 2001 and pain of the neck, shoulder, and lower back between 1991 and2001. Design: Biennial nationwide postal surveys, 1985-2001, and annual classroom surveys, 1996-2001. Setting: Finland. Participants: 62 677 12, 14, 16, and 18 year olds and 127 217 14-16 year olds. Main outcome measures: Pain in the back and neck, neck and shoulder, or lower back, at least weekly. Results: Prevalence of pain in the back and neck was greater in the 1990s than in the 1980s and increased steadily from 1993 to 1997. Pain of the neck and shoulder and pain of the lower back was much more common in 1999 than in 1991 and in 2001 than in 1999. Pain was more common among girls and older groups: pain of the neck and shoulder affected 24% of girls and 12% of boys in 14 year olds, 38% of girls and 16% of boys in 16 year olds, and 45% of girls and 19% of boys in 18 year olds; pain in the lower back affected 8% of girls and 7% of boys in 14 year olds, 14% of girls and 11% of boys in 16 year olds, and 17% of boysand 13% of girls in 18 year olds. Conclusion: Pain in the neck, shoulder, and lower back is becoming morecommon in Finnish adolescents. This pain suggests a new disease burden of degenerativemusculoskeletal disorders in future adults.

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 ≥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 ≥95th percentile cut-off point as obesity. RW ≥110% and ≥120%, calculated as the individuals 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.

Dietary Intervention in Infancy and Later Signs of Beta-Cell Autoimmunity

BACKGROUND Early exposure to complex dietary proteins may increase the risk of beta-cell autoimmunity and type 1 diabetes in children with genetic susceptibility. We tested the hypothesis that supplementing breast milk with highly hydrolyzed milk formula would decrease the cumulative incidence of diabetes-associated autoantibodies in such children. METHODS In this double-blind, randomized trial, we assigned 230 infants with HLA-conferred susceptibility to type 1 diabetes and at least one family member with type 1 diabetes to receive either a casein hydrolysate formula or a conventional, cows-milk-based formula (control) whenever breast milk was not available during the first 6 to 8 months of life. Autoantibodies to insulin, glutamic acid decarboxylase (GAD), the insulinoma-associated 2 molecule (IA-2), and zinc transporter 8 were analyzed with the use of radiobinding assays, and islet-cell antibodies were analyzed with the use of immunofluorescence, during a median observation period of 10 years (mean, 7.5). The children were monitored for incident type 1 diabetes until they were 10 years of age. RESULTS The unadjusted hazard ratio for positivity for one or more autoantibodies in the casein hydrolysate group, as compared with the control group, was 0.54 (95% confidence interval [CI], 0.29 to 0.95), and the hazard ratio adjusted for an observed difference in the duration of exposure to the study formula was 0.51 (95% CI, 0.28 to 0.91). The unadjusted hazard ratio for positivity for two or more autoantibodies was 0.52 (95% CI, 0.21 to 1.17), and the adjusted hazard ratio was 0.47 (95% CI, 0.19 to 1.07). The rate of reported adverse events was similar in the two groups. CONCLUSIONS Dietary intervention during infancy appears to have a long-lasting effect on markers of beta-cell autoimmunity--markers that may reflect an autoimmune process leading to type 1 diabetes. (ClinicalTrials.gov number, NCT00570102.).

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 familys 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 ≥4 h daily on viewing television. In girls using computer ≥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.

Infant Feeding in Finnish Children <7 yr of Age With Newly Diagnosed IDDM

Objective We studied associations between the type of feeding in infancy and the incidence of insulin-dependent diabetes mellitus (IDDM). Research Design And Methods We studied 103 newly diagnosed diabetic children <7 yr of age and 103 age- and sex-matched population-based control children in a countrywide study. Results The risk of IDDM was decreased (P < 0.05) among children breast-fed for at least 7 mo (odds ratio [OR] 0.45, 95% confidence interval [CI] 0.24–0.85) or exclusively breast-fed for at least 3 (OR 0.33, 95% CI 0.13–0.84) or 4 (OR 0.43, 95% CI 0.22–0.84) mo. Also, children who were ≥4 mo old at the time of introduction of supplementary milk feeding had a lower risk of diabetes (OR 0.48, 95% CI 0.26–0.91). Conclusions The protective effects of a long duration of breast-feeding and a late introduction of dairy products on the risk of IDDM remained significant after adjusting for the mothers education.

Neck or shoulder pain and low back pain in Finnish adolescents.

The aim of this study was to investigate the prevalence and determinants of self-reported neck or shoulder pain (NSP) and low back pain (LBP) among 12-18-year-olds. A questionnaire was mailed to a nationally representative sample of 11,276 12-, 14-, 16- and 18-year-olds in 1991. The response rate was 77%. NSP was perceived at least once a week by 15% of 12-18-year-olds and LBP by 8%. Both symptoms were more prevalent among girls than among boys, and the prevalence increased with age. Among the determinants investigated, the number of perceived psychosomatic symptoms had the strongest association with NSP and LBP. Our study confirmed the co-morbidity of NSP and LBP, and indicated that NSP is more frequent than believed among 16-18-year-old girls. The strong association of psychosomatic symptoms with NSP and LBP suggests that the latter two pain states could be more psychosomatic than nosiceptive in character.

Age at the Introduction of Solid Foods During the First Year and Allergic Sensitization at Age 5 Years

OBJECTIVE: The goal was to examine the relationship between age at the introduction of solid foods during the first year of life and allergic sensitization in 5-year-old children. METHODS: We analyzed data from the Finnish Type 1 Diabetes Prediction and Prevention nutrition study, a prospective, birth cohort study. We studied 994 children with HLA-conferred susceptibility to type 1 diabetes mellitus for whom information on breastfeeding, age at the introduction of solid foods, and allergen-specific immunoglobulin E levels at 5 years was available. The association between age at the introduction of solid foods and allergic sensitization was analyzed by using logistic regression. RESULTS: The median duration of exclusive breastfeeding was 1.8 months (range: 0–10 months). After adjustment for potential confounders, late introduction of potatoes (>4 months), oats (>5 months), rye (>7 months), wheat (>6 months), meat (>5.5 months), fish (>8.2 months), and eggs (>10.5 months) was significantly directly associated with sensitization to food allergens. Late introduction of potatoes, rye, meat, and fish was significantly associated with sensitization to any inhalant allergen. In models that included all solid foods that were significantly related to the end points, eggs, oats, and wheat remained the most important foods related to sensitization to food allergens, whereas potatoes and fish were the most important foods associated with inhalant allergic sensitization. We found no evidence of reverse causality, taking into account parental allergic rhinitis and asthma. CONCLUSION: Late introduction of solid foods was associated with increased risk of allergic sensitization to food and inhalant allergens.