Maternal gluten, cereal, and dietary fiber intake during pregnancy and lactation and the risk of islet autoimmunity and type 1 diabetes in the child.

BACKGROUND & AIMS: Maternal gluten intake in relation to child's risk of type 1 diabetes has been studied in few prospective studies considering the diet during pregnancy but none during lactation. Our aim was to study whether gluten, cereals, or dietary fiber in maternal diet during pregnancy and lactation is associated with the risk of islet autoimmunity or type 1 diabetes in the offspring. METHODS: We included 4943 children with genetic susceptibility to type 1 diabetes from the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) Study, born between 1996 and 2004. Maternal intake of gluten, different types of cereals, and dietary fiber were derived from a semi-quantitative validated food frequency questionnaire covering the eighth month of pregnancy and the third month of lactation. Children were monitored for islet autoantibodies up to age of 15 years and type 1 diabetes until year 2017. Risk of islet autoimmunity and clinical type 1 diabetes were estimated using Cox regression model, adjusted for energy intake, child's sex, HLA genotype, and familial diabetes. RESULTS: Altogether 312 children (6.4%) developed islet autoimmunity at median age of 3.5 (IQR 1.7, 6.6) years and 178 children (3.6%) developed type 1 diabetes at median age of 7.1 (IQR 4.3, 10.6) years. Gluten intake during pregnancy was not associated with islet autoimmunity (HR 0.96; 95% CI 0.68, 1.35), per 1 g/MJ increase in intake nor type 1 diabetes (HR 0.96; 95% CI 0.62, 1.50) in the offspring. Higher barley consumption during lactation was associated with increased risk of type 1 diabetes (HR 3.25; 95% CI 1.21, 8.70) per 1 g/MJ increase in intake. Maternal intake of other cereals or dietary fiber was not associated with the offspring outcomes. CONCLUSIONS: We observed no association between maternal intake of gluten, most consumed cereals, or dietary fiber during pregnancy or lactation and the risk of islet autoimmunity or type 1 diabetes in children from a high-risk population.

High levels of immunoglobulin G against cow's milk proteins and frequency of cow milk consumption are associated with the development of islet autoimmunity and type 1 diabetes - the TRIGR study.

BACKGROUND: The Trial to Reduce IDDM in the Genetically at Risk (TRIGR) (NCT00179777) found no difference type 1 diabetes risk between hydrolyzed and regular infant formula. However, cow's milk consumption during childhood is consistently linked to type 1 diabetes risk in prospective cohort studies. OBJECTIVE: Our primary aim was to study whether humoral immune responses to cow's milk and cow's milk consumption are associated with type 1 diabetes in TRIGR children. METHODS: TRIGR comprised 2159 children with genetic susceptibility to type 1 diabetes born between 2002-2007 in 15 countries. Children were randomized into groups receiving extensively hydrolyzed casein or a regular cow's milk formula and followed until age 10. Type 1 diabetes related autoantibodies and antibodies to cow's milk proteins were analyzed. Infant formula intake was measured by structured dietary interviews and milk consumption with a food frequency questionnaire. Associations of milk antibodies and milk consumption with the risk to develop type 1 diabetes were analysed by Cox survival model. RESULTS: Cow's milk antibody levels both in cord blood [HR for islet autoimmunity 1.30 (95% CI 1.05-1.61); type 1 diabetes 1.32 (1.02-1.71)] and longitudinally from birth to 3 years [islet autoimmunity 1.39 (1.07-1.81); type 1 diabetes 1.43 (1.04-1.96)] were associated with increased risk of developing type 1 diabetes. The amount of regular infant formula was associated with a reduced islet autoimmunity risk in the regular infant formula group [0.92 (0.85-0.99)]. Furthermore, frequent liquid milk consumption after infancy was associated with an increased risk of islet autoimmunity or type 1 diabetes. CONCLUSIONS: Elevated cow's milk antibody levels and high consumption of liquid milk after infancy are related to type 1 diabetes development in children with an increased genetic susceptibility to type 1 diabetes. Enhanced antibody levels to cow's milk may provide a biomarker of immune system prone to develop islet autoimmunity. TRIAL REGISTRY NUMBER: NCT00179777.

Gut Inflammation Markers, Diet, and Risk of Islet Autoimmunity in Finnish Children - A Nested Case-Control Study.

BACKGROUND: Gut dysbiosis and increased intestinal permeability have been reported to precede type 1 diabetes-related autoimmunity. The role of gut inflammation in autoimmunity is not understood. OBJECTIVES: This study aimed to assess whether gut inflammation markers are associated with risk of islet autoimmunity and whether diet is associated with gut inflammation markers. METHODS: A nested case-control sample of 75 case children with islet autoimmunity and 88 control children was acquired from the Finnish Type 1 Diabetes Prediction and Prevention cohort. Diet was assessed with 3-d food records, and calprotectin and human ß-defensin-2 (HBD-2) were analyzed from stool samples at 6 and 12 mo of age. Conditional logistic regression analysis was used in a matched case-control setting to assess risk of autoimmunity. Analysis of variance, independent samples t test, and a general linear model were used in secondary analyses to test associations of background characteristics and dietary factors with inflammation markers. RESULTS: In unadjusted analyses, calprotectin was not associated with risk of islet autoimmunity, whereas HBD-2 in the middle (odds ratio [OR]: 3.23; 95% confidence interval [CI]: 1.03, 10.08) or highest tertile (OR: 3.02; 95% CI: 1.05, 8.69) in comparison to the lowest at 12 mo of age showed borderline association (P-trend = 0.063) with higher risk of islet autoimmunity. Excluding children with cow milk allergy in sensitivity analyses strengthened the association of HBD-2 with islet autoimmunity, whereas adjusting for dietary factors and maternal education weakened it. At age 12 mo, higher fat intake was associated with higher HBD-2 (ß: 0.219; 95% CI: 0.110, 0.328) and higher intake of dietary fiber (ß: -0.294; 95% CI: -0.510, -0.078), magnesium (ß: -0.036; 95% CI: -0.059, -0.014), and potassium (ß: -0.003; 95% CI: -0.005, -0.001) with lower HBD-2. CONCLUSIONS: Higher HBD-2 in infancy may be associated with higher risk of islet autoimmunity. Dietary factors play a role in gut inflammatory status.

Intake of B vitamins and the risk of developing islet autoimmunity and type 1 diabetes in the TEDDY study.

PURPOSE: The aim was to study the association between dietary intake of B vitamins in childhood and the risk of islet autoimmunity (IA) and progression to type 1 diabetes (T1D) by the age of 10 years. METHODS: We followed 8500 T1D-susceptible children born in the U.S., Finland, Sweden, and Germany in 2004 -2010 from the Environmental Determinants of Diabetes in the Young (TEDDY) study, which is a prospective observational birth cohort. Dietary intake of seven B vitamins was calculated from foods and dietary supplements based on 24-h recall at 3 months and 3-day food records collected regularly from 6 months to 10 years of age. Cox proportional hazard models were adjusted for energy, HLA-genotype, first-degree relative with T1D, sex, and country. RESULTS: A total of 778 (9.2) children developed at least one autoantibody (any IA), and 335 (3.9%) developed multiple autoantibodies. 280 (3.3%) children had IAA and 319 (3.8%) GADA as the first autoantibody. 344 (44%) children with IA progressed to T1D. We observed that higher intake of niacin was associated with a decreased risk of developing multiple autoantibodies (HR 0.95; 95% CI 0.92, 0.98) per 1 mg/1000 kcal in niacin intake. Higher intake of pyridoxine (HR 0.66; 95% CI 0.46, 0.96) and vitamin B12 (HR 0.87; 95% CI 0.77, 0.97) was associated with a decreased risk of IAA-first autoimmunity. Higher intake of riboflavin (HR 1.38; 95% CI 1.05, 1.80) was associated with an increased risk of GADA-first autoimmunity. There were no associations between any of the B vitamins and the outcomes "any IA" and progression from IA to T1D.  CONCLUSION: In this multinational, prospective birth cohort of children with genetic susceptibility to T1D, we observed some direct and inverse associations between different B vitamins and risk of IA.

Detecting potential outliers in longitudinal data with time-dependent covariates.

BACKGROUND: Outliers can influence regression model parameters and change the direction of the estimated effect, over-estimating or under-estimating the strength of the association between a response variable and an exposure of interest. Identifying visit-level outliers from longitudinal data with continuous time-dependent covariates is important when the distribution of such variable is highly skewed. OBJECTIVES: The primary objective was to identify potential outliers at follow-up visits using interquartile range (IQR) statistic and assess their influence on estimated Cox regression parameters. METHODS: Study was motivated by a large TEDDY dietary longitudinal and time-to-event data with a continuous time-varying vitamin B12 intake as the exposure of interest and development of Islet Autoimmunity (IA) as the response variable. An IQR algorithm was applied to the TEDDY dataset to detect potential outliers at each visit. To assess the impact of detected outliers, data were analyzed using the extended time-dependent Cox model with robust sandwich estimator. Partial residual diagnostic plots were examined for highly influential outliers. RESULTS: Extreme vitamin B12 observations that were cases of IA had a stronger influence on the Cox regression model than non-cases. Identified outliers changed the direction of hazard ratios, standard errors, or the strength of association with the risk of developing IA. CONCLUSION: At the exploratory data analysis stage, the IQR algorithm can be used as a data quality control tool to identify potential outliers at the visit level, which can be further investigated.

Fruit, berry, and vegetable consumption and the risk of islet autoimmunity and type 1 diabetes in children-the Type 1 Diabetes Prediction and Prevention birth cohort study.

BACKGROUND: Prospective studies investigating the association among fruit, berry, and vegetable consumption and the risk of islet autoimmunity (IA) and type 1 diabetes (T1D) are few. OBJECTIVES: In this cohort study, we explored whether the consumption of fruits, berries, and vegetables is associated with the IA and T1D development in genetically susceptible children. METHODS: Food consumption data in the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) cohort study were available from 5674 children born between September 1996 and September 2004 in the Oulu and Tampere University Hospitals. Diet was assessed with 3-d food records at the age of 3 and 6 mo and annually from 1 to 6 y. The association between food consumption and the risk of IA and T1D was analyzed using joint models adjusted for energy intake, sex, human leukocyte antigen (HLA) genotype, and a family history of diabetes. RESULTS: During the 6-y follow-up, 247 children (4.4%) developed IA and 94 (1.7%) T1D. Furthermore, 64 of 505 children with at least 1 repeatedly positive autoantibody (12.7%) progressed from islet autoantibody positivity to T1D. The consumption of cruciferous vegetables was associated with decreased risk of IA [hazard ratio (HR): 0.83; 95% credible intervals (CI): 0.72, 0.95, per 1 g/MJ increase in consumption] and the consumption of berries with decreased risk of T1D (0.60; 0.47, 0.89). The consumption of banana was associated with increased risk of IA (1.08; 1.04, 1.12) and T1D (1.11; 1.01, 1.21). Only the association between banana and IA remain significant after multiple testing correction. CONCLUSIONS: In children genetically at risk for T1D, the consumption of cruciferous vegetables was associated with decreased risk of IA and consumption of berries with decreased risk of T1D. In addition, the consumption of banana was associated with increased risk of IA and T1D.

Dietary fatty acid intake in childhood and the risk of islet autoimmunity and type 1 diabetes: the DIPP birth cohort study.

PURPOSE: The aim was to study the associations between dietary intake of fatty acids in childhood and the risk of islet autoimmunity and type 1 diabetes (T1D). METHODS: The prospective Finnish Type 1 Diabetes Prediction and Prevention (DIPP) Study included children with genetic susceptibility to T1D born between 1996 and 2004. Participants were followed up every 3 to 12 months up to 6 years for diet, islet autoantibodies, and T1D. Dietary intake of several fatty acids at the age of 3 months to 6 years was assessed 1-8 times per participant with a 3-day food record. Joint models adjusted for energy intake, sex, HLA genotype and familial diabetes were used to investigate the associations of longitudinal intake of fatty acids and the development of islet autoimmunity and T1D. RESULTS: During the 6-year follow-up, 247 (4.4%) children of 5626 developed islet autoimmunity and 94 (1.7%) children of 5674 developed T1D. Higher intake of monounsaturated fatty acids (HR 0.63; 95% CI 0.47, 0.82), arachidonic acid (0.69; 0.50, 0.94), total n-3 fatty acids (0.64; 0.48, 0.84), and long-chain n-3 fatty acids (0.14; 0.04, 0.43), was associated with a decreased risk of islet autoimmunity with and without energy adjustment. Higher intake of total fat (0.73; 0.53, 0.98), and saturated fatty acids (0.55; 0.33, 0.90) was associated with a decreased risk of T1D only when energy adjusted. CONCLUSION: Intake of several fatty acids was associated with a decreased risk of islet autoimmunity or T1D among high-risk children. Our findings support the idea that dietary factors, including n-3 fatty acids, may play a role in the disease process of T1D.

Serum 25-hydroxyvitamin D and fatty acids in relation to the risk of microbial infections in children: The TRIGR Divia study.

BACKGROUND & AIMS: Nutrient status may affect the risk of microbial infections and play a role in modulating the immune response against such infections. The aim of this study was to determine whether serum 25-hydroxyvitamin D [25(OH)D] and serum fatty acids in infancy are associated with microbial infections by the age of 18 months. METHODS: Altogether 576 newborn infants from Trial to Reduce IDDM in the Genetically at Risk (TRIGR) born between 2002 and 2007 were included. The concentration of 25(OH)D vitamin and proportions of 26 fatty acids (presented as % of total fatty acids) were analyzed in cord blood serum and in sera taken at 6, 12, and 18 months of age. The cord blood samples and mean of 6-18-month values were used as exposures. Infections were detected by screening IgG antibodies against 10 microbes using enzyme immunoassay and antibodies against 6 coxsackievirus B serotypes by plaque neutralization assay in serum samples taken at 18 months of age. RESULTS: A higher proportion of n-3 polyunsaturated fatty acids (PUFAs) and especially long-chain n-3 PUFAs at birth and at the age of 6-18 months was associated with decreased risk of coxsackievirus B2 infection unadjusted and adjusted for region, case-control status, and maternal type 1 diabetes. Higher proportion of docosapentaenoic acid (DPA, 22:5 n-3) at birth was associated with a decreased risk of respiratory syncytial virus infection. 25(OH)D vitamin concentration was not consistently associated with the risk of infections. When only infected children were included docosahexaenoic acid (DHA, 22:6 n-3) and arachidonic acid (20:4 n-6) proportions were positively associated with IgG antibody levels against influenza A virus. 25(OH)D vitamin concentration showed an inverse association with rotavirus IgG levels among children with rotavirus seropositivity. CONCLUSIONS: In young children with increased susceptibility to type 1 diabetes, long-chain n-3 PUFAs may influence the risk of viral infections and immune response against the infections. However, this association may depend on the type of virus suggesting virus-specific effects.

Associations Between Serum Fatty Acids and Immunological Markers in Children Developing Islet Autoimmunity-The TRIGR Nested Case-Control Study.

Aims: Altered immune functions as well as fatty acid intake and status have been associated with the development of type 1 diabetes. We aimed to study the relationship between fatty acids and immunological markers in young children with increased genetic risk for type 1 diabetes in order to define putative mechanisms related to development of islet autoimmunity. Methods: Serum samples for fatty acid and immunological marker measurements were obtained in the Trial to Reduce IDDM in the Genetically at Risk (TRIGR) ancillary study (Divia) from children born between 2002 and 2007 in 15 countries. Case children (n = 95) were defined as having repeated positivity for at least two out of four diabetes-associated autoantibodies. For each case child, control children were selected matched for country and date of birth (n = 173). Serum fatty acids and immunological markers were measured from cord serum and at the age of 6 and 12 months. Spearman correlation coefficients were calculated between fatty acids and immunological markers. Results: Correlations between circulating fatty acids and immunological markers were different in case children who developed islet autoimmunity than in control children already at birth continuing across the first year of life. In case children, saturated fatty acids (SFAs) showed stronger correlations with immunological markers, while in controls, polyunsaturated fatty acids (PUFAs) showed stronger correlations. Conclusions: In cases, SFAs were associated with several immunological markers (CXCL10, IL-6, IL-9, IL-17, and CM-CSF) previously linked to the type 1 diabetes disease process. Findings indicate that fatty acids could have immunomodulatory potential in the early phase of the disease development, although causality between fatty acids and the immunological pathways remains to be explored. Trial registry number: NCT00179777.

Maternal Vitamin C and Iron Intake during Pregnancy and the Risk of Islet Autoimmunity and Type 1 Diabetes in Children: A Birth Cohort Study.

Our aim was to study the associations between maternal vitamin C and iron intake during pregnancy and the offspring's risk of developing islet autoimmunity and type 1 diabetes. The study was a part of the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) prospective birth cohort including children genetically at risk of type 1 diabetes born between 1997-2004. The diets of 4879 mothers in late pregnancy were assessed with a validated food frequency questionnaire. The outcomes were islet autoimmunity and type 1 diabetes. Cox proportional hazards regression analysis adjusted for energy, family history of diabetes, human leukocyte antigen (HLA) genotype and sex was used for statistical analyses. Total intake of vitamin C or iron from food and supplements was not associated with the risk of islet autoimmunity (vitamin C: HR 0.91: 95% CI (0.80, 1.03), iron: 0.98 (0.87, 1.10)) or type 1 diabetes (vitamin C: 1.01 (0.87, 1.17), iron: 0.92 (0.78, 1.08)), neither was the use of vitamin C or iron supplements associated with the outcomes. In conclusion, no association was found between maternal vitamin C or iron intake during pregnancy and the risk of islet autoimmunity or type 1 diabetes in the offspring.

Serum fatty acids and risk of developing islet autoimmunity: A nested case-control study within the TRIGR birth cohort.

BACKGROUND: Circulating fatty acids have been linked to development of type 1 diabetes. OBJECTIVES: To study the prospective associations of serum fatty acids with the risk of islet autoimmunity in high-risk children. METHODS: A nested case-control selection was carried out within the TRIGR cohort, which included infants with HLA (DQB1 or DQA1)-conferred disease susceptibility and a first-degree relative with type 1 diabetes, born between 2002 and 2007 in 15 countries and followed-up until 2017. The present study included 244 case children positive for at least two islet autoantibodies (ICA, IAA, GADA, and IA-2A) and two control children were matched for country and age. Proportions of 26 serum fatty acids at cord blood and at 6, 12, and 18 months of age were assessed using gas-chromatography. RESULTS: The average proportions of the following fatty acids were associated with an increased risk of islet autoimmunity, adjusted for sex, HLA risk, and maternal type 1 diabetes: pentadecanoic acid (15:0) (OR 3.41: 95% CI 1.70, 6.85), heptadecanoic acid (iso 17:0) (2.64: 1.62, 4.28) and (anteiso 17:0) (2.27: 1.39, 3.70), stearic acid (18:0) (23.8: 2.32, 244.6), and conjugated linoleic acid (18:2n-7) (2.60: 1.47, 4.59). Breastfeeding and not having maternal type 1 diabetes were positively associated with levels of the above-mentioned fatty acids. N-3 fatty acids were not consistently associated with islet autoimmunity. CONCLUSIONS: We found direct associations of pentadecanoic acid, heptadecanoic acid, stearic acid, and conjugated linoleic acid with the risk of islet autoimmunity. Further studies are needed to understand the complex role of fatty acids in the development of type 1 diabetes.

Perinatal factors and the risk of type 1 diabetes in childhood and adolescence-A register-based case-cohort study in Finland, years 1987 to 2009.

OBJECTIVES: Our aim was to clarify previously reported associations and to explore new ones between various maternal background and perinatal factors and the risk of type 1 diabetes in childhood. METHODS: We identified all children born 1 January 1987 to 31 December 2008 in Finland and diagnosed with type 1 diabetes by age 16 years or end of 2009 from the Special Reimbursement Register (n = 6862). A 10% random sample from each birth year cohort was selected as a reference cohort (n = 127 216). Information on perinatal factors was obtained from the Finnish Medical Birth Register. RESULTS: Maternal diabetes (hazard ratios [HR] = 6.43; 95% confidence interval [CI] 5.35, 7.73), maternal asthma (HR = 1.23; 95% CI 1.06, 1.43), child's high birth length for gestational age (HR = 1.35; 95% CI 1.22, 1.51 highest vs lowest quintile) and premature or early term birth (HR = 1.21; 95% CI 1.05, 1.39 gestational weeks 33-36 and HR = 1.17; 95% CI 1.09, 1.26 gestational weeks 37-38 vs gestational weeks 39-40) was associated with an increased risk of type 1 diabetes when adjusted for several potential confounders. Maternal smoking during pregnancy (HR = 0.72; 95% CI 0.66, 0.77), high number of previous live births (HR = 0.65; 95% CI 0.55, 0.76 ≥ 4 vs 0 live births), and the child being born small for gestational age (HR = 0.80; 95% CI 0.67, 0.96) was associated with a decreased risk of type 1 diabetes. CONCLUSIONS: Findings on maternal asthma and high birth length for gestational age increasing the risk of type 1 diabetes are novel and need to be confirmed. Our findings indicate that perinatal factors may play a role in the development of type 1 diabetes.

Enterovirus Infections Are Associated With the Development of Celiac Disease in a Birth Cohort Study.

Enterovirus and adenovirus infections have been linked to the development of celiac disease. We evaluated this association in children who developed biopsy-proven celiac disease (N = 41) during prospective observation starting from birth, and in control children (N = 53) matched for the calendar time of birth, sex, and HLA-DQ genotype. Enterovirus and adenovirus infections were diagnosed by seroconversions in virus antibodies in longitudinally collected sera using EIA. Enterovirus infections were more frequent in case children before the appearance of celiac disease-associated tissue transglutaminase autoantibodies compared to the corresponding period in control children (OR 6.3, 95% CI 1.8-22.3; p = 0.005). No difference was observed in the frequency of adenovirus infections. The findings suggest that enterovirus infections may contribute to the process leading to celiac disease.

Association of Cereal, Gluten, and Dietary Fiber Intake With Islet Autoimmunity and Type 1 Diabetes.

IMPORTANCE: Dietary proteins, such as gluten, have been suggested as triggers of the disease process in type 1 diabetes (T1D). OBJECTIVE: To study the associations of cereal, gluten, and dietary fiber intake with the development of islet autoimmunity (IA) and T1D. DESIGN, SETTING, AND PARTICIPANTS: The prospective birth cohort Finnish Type 1 Diabetes Prediction and Prevention Study recruited children with genetic susceptibility to type 1 diabetes from September 1996 to September 2004 from 2 university hospitals in Finland and followed up every 3 to 12 months up to 6 years for diet, islet autoantibodies, and T1D. Altogether 6081 infants (78% of those invited) participated in the study. Dietary data were available for 5714 children (94.0%) and dietary and IA data were available for 5545 children (91.2%), of whom 3762 (68%) had data on islet autoantibodies up to age 6 years. Information on T1D was available for all children. Data were analyzed in 2018 and end point data were updated in 2015. EXPOSURES: Each child's intake of cereals, gluten, and dietary fiber was calculated from repeated 3-day food records up to 6 years. MAIN OUTCOMES AND MEASURES: Islet autoimmunity was defined as repeated positivity for islet cell antibodies and at least 1 biochemical autoantibody of 3 analyzed, or T1D. Data on the diagnosis of T1D were obtained from Finnish Pediatric Diabetes Register. RESULTS: Of 5545 children (2950 boys [53.2%]), 246 (4.4%) developed IA and of 5714 children (3033 boys [53.1%]), 90 (1.6%) developed T1D during the 6-year follow-up. Based on joint models, the intake of oats (hazard ratio [HR], 1.08; 95% CI, 1.03-1.13), wheat (HR, 1.09; 95% CI, 1.03-1.15), rye (HR, 1.13; 95% CI, 1.03-1.23), gluten-containing cereals (HR, 1.07; 95% CI, 1.03-1.11), gluten without avenin from oats (HR, 2.23; 95% CI, 1.40-3.57), gluten with avenin (HR, 2.06; 95% CI, 1.45-2.92), and dietary fiber (HR, 1.41; 95% CI, 1.10-1.81) was associated with the risk of developing IA (HRs for 1 g/MJ increase in intake). The intake of oats (HR, 1.10; 95% CI, 1.00-1.21) and rye (HR, 1.20; 95% CI, 1.03-1.41) was associated with the risk of developing T1D. After multiple testing correction, the associations with IA remained statistically significant. CONCLUSIONS AND RELEVANCE: A high intake of oats, gluten-containing cereals, gluten, and dietary fiber was associated with an increased risk of IA. Further studies are needed to confirm or rule out the findings and study potential mechanisms.

A Joint Modeling Approach for Childhood Meat, Fish and Egg Consumption and the Risk of Advanced Islet Autoimmunity.

Several dietary factors have been suspected to play a role in the development of advanced islet autoimmunity (IA) and/or type 1 diabetes (T1D), but the evidence is fragmentary. A prospective population-based cohort of 6081 Finnish newborn infants with HLA-DQB1-conferred susceptibility to T1D was followed up to 15 years of age. Diabetes-associated autoantibodies and diet were assessed at 3- to 12-month intervals. We aimed to study the association between consumption of selected foods and the development of advanced IA longitudinally with Cox regression models (CRM), basic joint models (JM) and joint latent class mixed models (JLCMM). The associations of these foods to T1D risk were also studied to investigate consistency between alternative endpoints. The JM showed a marginal association between meat consumption and advanced IA: the hazard ratio adjusted for selected confounding factors was 1.06 (95% CI: 1.00, 1.12). The JLCMM identified two classes in the consumption trajectories of fish and a marginal protective association for high consumers compared to low consumers: the adjusted hazard ratio was 0.68 (0.44, 1.05). Similar findings were obtained for T1D risk with adjusted hazard ratios of 1.13 (1.02, 1.24) for meat and 0.45 (0.23, 0.86) for fish consumption. Estimates from the CRMs were closer to unity and CIs were narrower compared to the JMs. Findings indicate that intake of meat might be directly and fish inversely associated with the development of advanced IA and T1D, and that disease hazards in longitudinal nutritional epidemiology are more appropriately modeled by joint models than with naive approaches.

Infant Feeding in Relation to the Risk of Advanced Islet Autoimmunity and Type 1 Diabetes in Children With Increased Genetic Susceptibility: A Cohort Study.

Breastfeeding, age at introduction of foods, and food diversity in infancy were studied for associations with advanced islet autoimmunity and type 1 diabetes. During 1996--2004, a total of 5,915 newborns with human leukocyte antigen-conferred susceptibility to type 1 diabetes were enrolled in the prospective Finnish Type 1 Diabetes Prediction and Prevention Nutrition Study. Children were assessed at intervals of 3-12 months for the appearance of 4 types of islet autoantibodies and type 1 diabetes up to the age of 15 years. Survival models indicated the 3 variables of interest were not associated with advanced islet autoimmunity or type 1 diabetes in the cohort. Early introduction of solid foods was associated with increased risk of advanced islet autoimmunity in children up to age 3 years (for <3 months vs. >4 months, hazard ratio = 2.33, 95% confidence interval: 1.39, 3.91; for 3-4 months vs. >4 months, hazard ratio = 2.18; 95% confidence interval: 1.38, 3.47) but not in longer follow-up (P for interaction = 0.046). Similar results were observed for age at introduction of roots, cereals, egg, and meat relative to risk of advanced islet autoimmunity. No consistent, long-term associations between infant feeding and advanced islet autoimmunity or type 1 diabetes were observed.

Moderators of Maintained Increase in Aerobic Exercise Among Aging Men and Women in a 4-Year Randomized Controlled Trial: The DR's EXTRA Study.

BACKGROUND: Little is known about factors that modify the effectiveness of exercise interventions in increasing exercise. We aimed to identify moderators of the effectiveness of aerobic exercise intervention in maintaining increased aerobic exercise among older individuals. METHODS: The participants of a 4-year randomized controlled trial were a population sample of 1410 men and women aged 57 to 78 years. The aerobic exercise group included 185 individuals and the control group included 169 individuals who reported low aerobic exercise at baseline. Maintained increase in aerobic exercise was defined as at least 60-minute increase in moderate-to-heavy aerobic exercise per week from baseline to 2- and 4-year assessments. RESULTS: Individuals in the aerobic exercise group were 2.5 (95% CI 1.5 to 3.9) times more likely to maintain increased aerobic exercise than those in the control group. Individuals aged < 68.5 years but not older individuals succeeded in maintaining increased aerobic exercise in the intervention group (P = .02 for interaction). Individuals who were past smokers (P = .02 for interaction), were working (P = .05 for interaction), or had symptoms of depression (P = .05 for interaction) succeeded better in maintaining increased aerobic exercise in the intervention group than other individuals. CONCLUSIONS: These findings help in more precise targeting of future exercise interventions among older individuals.

Cardiorespiratory fitness and metabolic syndrome in older men and women: the dose responses to Exercise Training (DR's EXTRA) study.

OBJECTIVE: We studied the association of maximum oxygen uptake (Vo(2max)) with the development and resolution of metabolic syndrome (MetS) for 2 years in older individuals. RESEARCH DESIGN AND METHODS: Subjects were a population sample of 1,226 men and women aged 57-78 years. We assessed Vo(2max) directly by respiratory gas analysis during maximum exercise testing and used dichotomous and continuous variables for MetS. RESULTS: One SD increase in baseline Vo(2max) associated with 44% (95% CI 24-58) decreased risk of developing MetS. Individuals in the highest third of baseline Vo(2max) were 68% (37-84) less likely to develop MetS than those in the lowest third. One SD increase in Vo(2max) increased the likelihood to resolve MetS 1.8 (1.2-2.8) times. Individuals in the highest Vo(2max) third were 3.9 (1.5-9.9) times more likely to resolve MetS than those in the lowest third. CONCLUSIONS: Higher levels of cardiorespiratory fitness protect against MetS and may resolve it in older individuals.