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Riitta Veijola

Publications and source records attributed to Riitta Veijola.

At least 19 recordsLinked to original sources

International consensus guidance for general population screening for islet autoantibodies to diagnose early-stage type 1 diabetes: a nominal group technique process.

Type 1 diabetes is an autoimmune disease that targets and destroys insulin-producing beta cells in the pancreatic islets. The incidence of type 1 diabetes is rising globally. At the clinical diagnosis of type 1 diabetes, between 20% and 67% of children and adolescents present with diabetic ketoacidosis (DKA) requiring hospitalisation, and one-third of these require intensive care. Type 1 diabetes can be detected in early stages, prior to the insulin-requiring clinical diagnosis, through screening for islet autoantibodies (IAbs). Identifying individuals with early-stage type 1 diabetes, combined with monitoring of and education on disease progression, prevents DKA and results in a milder clinical onset. This allows for timely insulin initiation in outpatient settings and improved long-term glucose management. Early diagnosis also enables access to novel disease-modifying therapies that can delay the clinical onset of diabetes. In this international consensus, we provide guidance on the principles and practice of implementing general population screening for IAbs to diagnose early-stage type 1 diabetes. We also outline the minimum requirements for establishing effective population screening programmes to diagnose early-stage type 1 diabetes through IAb detection. This consensus statement has been endorsed by the following professional associations: Advanced Technologies & Treatments for Diabetes (ATTD); Association of Diabetes Care and Education Specialists (ADCES); Association Belge Du Diabète; Associazione Medici Diabetologi (AMD); Australian Diabetes Society (ADS); Belgian Diabetes Liga; Breakthrough T1D; Czech Diabetes Society (ČDS); EASD; Finnish Diabetes Association (FDS); Fondazione Italiana Diabete (FID); International Diabetes Federation (IDF)-Europe; International Society of Paediatric and Adolescent Diabetes (ISPAD); Paediatric Endocrinology Nursing Society (PENS); Polish Diabetes Society; Portuguese Diabetes Association (APDP); Sociedade Portuguesa de Diabetologia (SPD); Società Italiana di Diabetologia (SID); Société Francophone du Diabète (SFD) and Type 1 Diabetes Exchange (T1D Exchange).

Consensus report↗

Human leukocyte antigen non-class II determinants for type 1 diabetes in the Finnish population.

We explored the contribution of non-class II HLA loci to type 1 diabetes genetic susceptibility in the Finnish population. We analyzed 11 markers covering a 4-Mb region telomeric to the DQB1 gene in Finnish nuclear families with parents carrying either the DR8-DQB1*04 (n=188) or the DRB1*0404-DQB1*0302 haplotypes (n=135). On the DRB1*0404-DQB1*0302 haplotype we found independent disease association of the D6S273 and C125 markers (p(corr) = 10(-4) and 0.0095, respectively). The C125*200 alleles on this haplotype conferred an increased disease risk (OR = 3.6; p = 0.003). The B*39 allele also showed disease association (OR = 2.6; p = 0.054). The C125*200 allele appeared at an increased frequency also on transmitted B39 positive DRB1*0404-DQB1*0302 haplotypes, suggesting an independent effect. In addition, the C143*417 allele on the DRB1*08-DQB1*04 haplotype was associated with decreased disease risk (OR = 0.48, p = 0.003). Our data confirm that non-class II HLA loci affect genetic susceptibility to type 1 diabetes. In addition to HLA B*39 the C125 locus contributes to disease risk on the Finnish DRB1*0404-DQB1*0302 haplotypes. Another locus close to D6S273 may also have an effect. For the first time we report that a locus near the C143 marker appear to affect disease association of the DRB1*08-DQB1*04 haplotype.

Alleles↗

Enteral virus infections in early childhood and an enhanced type 1 diabetes-associated antibody response to dietary insulin.

Enteral virus infections may trigger the development of beta-cell-specific autoimmunity by interacting with the gut-associated lymphoid system. We analyzed the effect of three different virus infections on immunization to dietary insulin in children carrying increased genetic risk for type 1 diabetes. Forty-six of 238 children developed multiple diabetes-associated autoantibodies and 31 clinical diabetes (median follow-up time 75 months). Insulin-binding antibodies were measured with EIA method (median follow-up time 24 months). Antibodies to enteroviruses, rotavirus and adenovirus were measured with EIA in samples drawn at birth and the ages of 3 and 6 months. Nineteen enterovirus, 14 rotavirus and 8 adenovirus infections were diagnosed. At the ages of 6, 12, and 18 months, the concentrations of insulin-binding antibodies were higher in children with postnatal entero-, rota- and/or adenovirus infections than in children without these infections. Children who subsequently developed ICA or IA-2 antibodies or clinical type 1 diabetes had higher concentrations of insulin-binding antibodies than children who remained autoantibody negative. Our data suggest that enteral virus infections can enhance immune response to insulin, induced primarily by bovine insulin in cow's milk. An enhanced antibody response to dietary insulin preceded the development of beta-cell specific autoimmunity and type 1 diabetes.

Administration, Oral↗

Dietary intake and use of dietary supplements in relation to demographic variables among pregnant Finnish women.

Proper nutrition during pregnancy may be important for maternal health and fetal growth and development. In Finland, targeted recommendations are given to guide pregnant women in their food choice and dietary supplement use so that they may obtain adequate nutritional status and meet the increased need for nutrients. The aims of the present study were to examine food choices, nutrient intake and dietary supplement use of pregnant Finnish women in association with demographic variables. One thousand and seventy-five families were invited to a birth cohort study during 1998-9. Mothers of 797 newborns completed a validated 181-item food-frequency questionnaire from which the food and nutrient intakes were calculated. The information about supplement use was collected concerning the whole pregnancy. The results of the present study suggest that healthy food choices are rather common among pregnant Finnish women and the choices are positively correlated with age and education. Nutrient supplements were used by 85 % of the women. Supplements were favoured by the older and well-educated women and by those who had normal weight before pregnancy. Of the women in the present study, 31 % received vitamin A-containing supplements, although it is not recommended during pregnancy. Taking food and supplementation into account, the intake of vitamin D did not meet the dietary recommendation and folic acid intake was below recommendation in 44 % of the women. Therefore there seemed to be unnecessary nutrient supplementation and at the same time lack of relevant supplementation among these pregnant women.

Adult↗

Early epitope- and isotype-specific humoral immune responses to GAD65 in young children with genetic susceptibility to type 1 diabetes.

OBJECTIVE: The pattern of the humoral immunity to disease-associated autoantigens may reflect the severity of the autoimmune disease process. The purpose of this study was to delineate the maturation of the humoral immunity to one of the main autoantigens in type 1 diabetes (T1D), glutamic acid decarboxylase (GAD65). DESIGN AND METHODS: Serum samples were obtained for the detection of epitope- and isotype-specific antibodies sequentially with short intervals from 36 young children with HLA-conferred genetic susceptibility to T1D starting from the first appearance of GAD65Ab. During prospective observation, ten children developed T1D. Antibodies were analyzed using biotinylated anti-human immunoglobulin (Ig) antibodies and chimeric GAD molecules in radio-binding assays. RESULTS: The immune response to GAD65 started as reactivity to the middle region and spread rapidly to the C-terminal region. IgG1 antibodies dominated among the isotypes from the first appearance of GAD65Ab, while other IgG subclasses were observed to a lesser extent. IgG4 antibodies emerged clearly as the last IgG subclass. A broad initial response comprising three to four IgG subclasses and the lack of an emerging IgG4 response during follow-up was associated with increased risk for progression to clinical diabetes (P<0.05). CONCLUSIONS: The humoral response to GAD65 epitope clusters is relatively uniform in young children, whereas there is conspicuous individual variation in IgG subclass responses except for IgG1. A narrow initial IgG subclass response to GAD65 and the emergence of IgG4 antibodies were characteristic of those who remained non-diabetic over the first few years of GAD65 autoimmunity.

Antibody Formation↗

Noninvasive diagnosis of focal hyperinsulinism of infancy with [18F]-DOPA positron emission tomography.

Congenital hyperinsulinism of infancy (CHI) is characterized by severe hypoglycemia due to dysregulated insulin secretion, associated with either focal or diffuse pathology of the endocrine pancreas. The focal condition is caused by a paternally inherited mutation in one of the genes encoding the subunits of the beta-cell ATP-sensitive potassium channel (SUR1/ABCC8 or Kir6.2/KCNJ11) and somatic loss of maternal 11p15 alleles within the affected area. Until now, preoperative diagnostics have relied on technically demanding and invasive catheterization techniques. We evaluated the utility of fluorine-18 l-3,4-dihydroxyphenylalanine ([(18)F]-DOPA) positron emission tomography (PET) to identify focal pancreatic lesions in 14 CHI patients, 11 of which carried mutations in the ABCC8 gene (age 1-42 months). To reduce bias in PET image interpretation, quantitative means for evaluation of pancreatic [(18)F]-DOPA uptake were established. Five patients had a visually apparent focal accumulation of [(18)F]-DOPA and standardized uptake value (SUV) >50% higher (mean 1.8-fold) than the maximum SUV of the unaffected part of the pancreas. When these patients were operated on, a focus of 4-5 x 5-8 mm matching with the PET scan was found, and all were normoglycemic after resection of the focus. The remaining nine patients had diffuse accumulation of [(18)F]-DOPA in the pancreas (SUV ratio <1.5). Diffuse histology was verified in four of these, and pancreatic catheterization was consistent with diffuse pathology in four cases. In conclusion, [(18)F]-DOPA PET is a promising noninvasive method for the identification and localization of the focal form of CHI.

Child, Preschool↗

[Not Available].

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Journal Article↗

Lack of association of PAX4 gene with type 1 diabetes in the Finnish and Hungarian populations.

We aimed to assess the possible contribution of the PAX4 transcription factor gene to the genetic background of type 1 diabetes. We analyzed four coding polymorphisms of the PAX4 gene in 498 cases with type 1 diabetes and 825 control subjects from Finland and Hungary. All patients were diagnosed under the age of 15 years according to the World Health Organization criteria. All four PAX4 variants (three in exon 9 and one in exon 3) were genotyped using DNA sequencing. In addition, all Finnish subjects were typed for HLA DR-DQ, insulin gene (-23) HphI, and CTLA4 CT60 polymorphisms. The +1,168 C/A coding variant of PAX4 was found to be polymorphic in both populations (P321H, rs712701). No difference was observed in the genotype frequencies between cases and control subjects, nor was any disease association detected when patients were stratified according to age at diagnosis, sex, HLA, insulin gene, or CTLA4 genotypes. Our data indicate that the +1,168 C/A variant of PAX4 gene does not play any essential role in genetic type 1 diabetes susceptibility. The strong coherence between the datasets of the two ethnic groups studied with highly contrasting disease incidence, socioeconomic characteristics, and profoundly diverse environment emphasizes the impact of this finding.

Adolescent↗

Environmental triggers and determinants of type 1 diabetes.

Type 1 diabetes is perceived as a chronic immune-mediated disease with a subclinical prodromal period characterized by selective loss of insulin-producing beta-cells in the pancreatic islets in genetically susceptible subjects. A series of evidence supports a critical role of exogenous factors in the development of type 1 diabetes, such as 1) the fact that <10% of individuals with HLA-conferred diabetes susceptibility do progress to clinical disease, 2) a pairwise concordance of type 1 diabetes of <40% among monozygotic twins, 3) a more than 10-fold difference in the disease incidence among Caucasians living in Europe, 4) a several-fold increase in the incidence over the last 50 years, and 5) migration studies indicating that the disease incidence has increased in population groups who have moved from a low-incidence to a high-incidence region. This article discusses the trigger-booster hypothesis claiming that the diabetic disease process is triggered by an exogenous factor with definite seasonal variation and driven by one or several other environmental determinants. In addition, there are a series of modifying factors affecting the fate and pace of the process. Accordingly, progression to clinical type 1 diabetes typically requires the unfortunate combination of genetic disease susceptibility, a diabetogenic trigger, and a high exposure to a driving antigen.

Aging↗

Use of vitamin D and other dietary supplements by Finnish children at the age of 2 and 3 years.

The aims of this study were to investigate the frequency of the use of vitamin D and other dietary supplements by Finnish children at the age of 2 and 3 years, to evaluate daily nutrient intake from supplements, and to investigate the relation between supplement use and various sociodemographic factors. The families of 534 newborn infants were invited to a birth cohort study in 1996-1997. Families of 292 children at the child's age of 2 years and families of 263 children at the age of 3 years completed a three-day food record from which the daily use of dietary supplements was calculated. The frequency of dietary supplement use was 50% among the two-year-olds, and 37% among the three-year-old children. The most commonly used supplements among the two-year-olds were vitamin D or vitamin A + D combination (38%) and fluoride (16%) and among the three-year-olds fluoride (19%) and multivitamins (16%), respectively. Intake of nutrients other than vitamin D or fluoride from supplements was rare among two-year-olds, whereas 16% of the three-year-olds received also vitamin A, C, E, and several group B vitamins. Mean daily intake of vitamin D from supplements was 6.7 micrograms at the age of 2 years and 5.3 micrograms at the age of 3 years, respectively. The level of parental education was positively associated with the child's vitamin D supplementation at the age of 2 years. As the compliance with national recommendations of vitamin D supplementation was low, intensified counseling of the parents is needed at the well-baby clinics in Finland.

Age Distribution↗

Linkage and association mapping of the LRP5 locus on chromosome 11q13 in type 1 diabetes.

Linkage of chromosome 11q13 to type 1 diabetes (T1D) was first reported from genome scans (Davies et al. 1994; Hashimoto et al. 1994) resulting in P <2.2 x 10(-5) (Luo et al. 1996) and designated IDDM4 ( insulin dependent diabetes mellitus 4). Association mapping under the linkage peak using 12 polymorphic microsatellite markers suggested some evidence of association with a two-marker haplotype, D11S1917*03-H0570POLYA*02, which was under-transmitted to affected siblings and over-transmitted to unaffected siblings ( P=1.5 x 10(-6)) (Nakagawa et al. 1998). Others have reported evidence for T1D association of the microsatellite marker D11S987, which is approximately 100 kb proximal to D11S1917 (Eckenrode et al. 2000). We have sequenced a 400-kb interval surrounding these loci and identified four genes, including the low-density lipoprotein receptor related protein (LRP5) gene, which has been considered as a functional candidate gene for T1D (Hey et al. 1998; Twells et al. 2001). Consequently, we have developed a comprehensive SNP map of the LRP5 gene region, and identified 95 SNPs encompassing 269 kb of genomic DNA, characterised the LD in the region and haplotypes (Twells et al. 2003). Here, we present our refined linkage curve of the IDDM4 region, comprising 32 microsatellite markers and 12 SNPs, providing a peak MLS=2.58, P=5 x 10(-4), at LRP5 g.17646G>T. The disease association data, largely focused in the LRP5 region with 1,106 T1D families, provided no further evidence for disease association at LRP5 or at D11S987. A second dataset, comprising 1,569 families from Finland, failed to replicate our previous findings at LRP5. The continued search for the variants of the putative IDDM4 locus will greatly benefit from the future development of a haplotype map of the genome.

Chromosome Mapping↗

Haplotype structure, LD blocks, and uneven recombination within the LRP5 gene.

Patterns of linkage disequilibrium (LD) in the human genome are beginning to be characterized, with a paucity of haplotype diversity in "LD blocks," interspersed by apparent "hot spots" of recombination. Previously, we cloned and physically characterized the low-density lipoprotein-receptor-related protein 5 (LRP5) gene. Here, we have extensively analysed both LRP5 and its flanking three genes, spanning 269 kb, for single nucleotide polymorphisms (SNPs), and we present a comprehensive SNP map comprising 95 polymorphisms. Analysis revealed high levels of recombination across LRP5, including a hot-spot region from intron 1 to intron 7 of LRP5, where there are 109 recombinants/Mb (4882 meioses), in contrast to flanking regions of 14.6 recombinants/Mb. This region of high recombination could be delineated into three to four hot spots, one within a 601-bp interval. For LRP5, three haplotype blocks were identified, flanked by the hot spots. Each LD block comprised over 80% common haplotypes, concurring with a previous study of 14 genes that showed that common haplotypes account for at least 80% of all haplotypes. The identification of hot spots in between these LD blocks provides additional evidence that LD blocks are separated by areas of higher recombination.

3' Flanking Region↗

Vitamin D receptor polymorphisms: no association with type 1 diabetes in the Finnish population.

OBJECTIVE: The effect of polymorphisms of the vitamin D receptor (VDR) gene on susceptibility to type 1 diabetes has recently been investigated extensively. Several findings on positive disease associations have been observed and, in addition, a protective effect of vitamin D supplementation has been reported. DESIGN: We studied the effect of three vitamin D receptor gene polymorphisms (VDRA, VDRB, VDRF) on susceptibility to type 1 diabetes in a large case-control series (more than 2000 controls and about 1000 patients) from the Finnish population. METHODS: A combination of case-control and affected-family based approaches was used. Subjects were genotyped for VDRA (ApaI), VDRB (BsmI) and VDRF (FokI) single nucleotide polymorphisms using a minisequencing reaction. RESULTS: A few borderline significant associations were observed with both approaches used. In the case-control association analyses we found significant differences between cases and controls in frequencies of VDRB (P=0.024, all subjects and P=0.016, HLA DQB1*0302-positive subjects) and VDRF (P=0.0063, Turku cohort). In the total family set a decreased (39.3%) transmission of the VDRA-VDRB-VDRF haplotype 1-1-2 and an increased (60.3%) transmission of haplotype 2-1-2 to sons was seen (P=0.0059 and P=0.024 respectively). Transmission of the haplotype 2-2-1 to daughters was decreased (37.6%, P=0.022). Interestingly, we also observed significant differences in allele frequencies of the polymorphisms studied between populations from three different regions in Finland. CONCLUSIONS: All these differences disappeared after correction for multiple testing. We conclude that the single nucleotide polymorphisms analysed are unlikely to be associated with type 1 diabetes in the Finnish population.

Adolescent↗

Androgen receptor gene exon 1 CAG repeat polymorphism in Finnish patients with childhood-onset type 1 diabetes.

OBJECTIVE: Animal models suggest that androgen receptor gene polymorphisms might affect disease predisposition in human immune-mediated diabetes. The aim of this study was to investigate the effect of the human androgen receptor gene exon 1 CAG repeat polymorphisms on type 1 diabetes (T1D) susceptibility. DESIGN AND METHODS: A combined strategy of case-control and family-based approaches was used. Affected sibling pair families (n=120), nuclear families (n=645) and cohorts of sporadic cases (n=208) and controls (n=1381) were genotyped for androgen receptor gene exon 1 CAG repeat polymorphism. An automated fluorescence-based DNA fragment-sizing method was used. RESULTS: The distribution of CAG repeat alleles did not differ significantly between patients and controls. However, short repeat alleles (7-14) were more prevalent among cases in girls compared with controls (8.77% vs 5.91%; P=0.03). Long repeat alleles (19-28) were less frequent among HLA DR3-positive diseased boys than in DR3-positive control boys (32.6% vs 40.6%; P=0.011). The differences were not significant after adjustment for multiple comparisons. Transmission of CAG repeat alleles was not different from expected in the total material. However, transmissions to girls deviated from the expected value significantly (extended transmission disequilibrium test (ETDT) 37.82; P=0.0016). A decreased transmission of the alleles with 13, 20 and 26 repeats to girls was observed (T%0, P=0.046; T%25.5, P=0.0003, T%0, P=0.025). CONCLUSION: The results do not support a common role for the androgen receptor gene exon 1 CAG repeat in T1D susceptibility; however, an effect of a disease variant in linkage disequilibrium could be detected.

Adolescent↗

Estimation of genetic risk for type 1 diabetes.

The most important gene loci defining risk of type 1 diabetes mellitus (T1DM) are located within the HLA gene region. HLA-DQ molecules are of primary importance but HLA-DR gene products modify the risk conferred by HLA-DQ. The risk associated with an HLA genotype is defined by the particular combination of susceptible and protective alleles. The highest risk is associated with a combination of two different risk haplotypes (7% risk to develop T1DM in Finland) whereas protective genotypes covering 69% of population have a risk of less than 0.2%). The complicated analysis of HLA genotypes is simplified by strong linkage disequilibrium between HLA-DRB1, -DQA1 and -DQB1 loci. In many cases one can deduce the alleles of other loci based on determination of the alleles in one locus. Differences between various populations in the frequency of marker alleles and in the linkages between them has to be taken into account. We have developed PCR based typing methods that utilize blood spot samples, microtiter plate format and lanthanide labeled oligonucleotide probes to define HLA-DQ and -DR alleles relevant for T1DM risk. Typing is run stepwise so that after initial HLA-DQB1 typing only those samples will be further analyzed in which -DQA1 or -DRB1 typing is informative and expected to contribute to the risk estimation. This method has been used to screen more than 50,000 newborn infants in Finland over a time period of 6 years, and it has been able to identify most children who have developed T1D during the follow-up period. The efficiency of the procedure has also been tested in Finnish and Greek populations.

Diabetes Mellitus, Type 1↗

Humoral beta-cell autoimmunity in relation to HLA-defined disease susceptibility in preclinical and clinical type 1 diabetes.

We have studied the relationship between diabetes-associated autoantibodies and various HLA genotypes and alleles in patients with newly diagnosed type 1 diabetes, in non-diabetic siblings and in children representing the general population to test the hypothesis that specific HLA genes regulate the humoral immune response to various autoantigens. Among the newly diagnosed patients we observed that those carrying the DR4-DQB1*0302 haplotype had increased levels of insulin autoantibodies (IAA) and IA-2 antibodies (IA-2A), but low levels of GAD antibodies (GADA). In contrast, those with the DR3-DQB1*02 haplotype had increased GADA titers but low IAA and IA-2 levels. DQB1*02-homozygous patients had a conspicuously low frequency and low levels of IA-2A. Among the siblings there was an apparent association between genetic risk and the prevalence of islet cell antibodies (ICA), IAA, GADA, IA-2A and multiple autoantibodies, the latter being detectable at a frequency of 24.1% in high risk siblings and at a frequency of only 0.9% in those with genotypes conferring disease protection. Among 7-16-year-old Finnish schoolchildren there was an association between GADA and the DQB1*02/*0302 genotype and the DQB1*0302 allele. Among young children identified from the general population based on high (DQB1*02/0302 heterozygosity) or moderate (DQB1*0302/x; x not equal *02, *0301, *0602, *0603) genetic risk for type 1 diabetes the high risk children seroconverted more often to positivity for ICA, GADA and IA-2A over their first 2 years of life. Among older sibs of these children we observed an obvious relationship between the degree of genetic risk and the frequency of ICA, IAA, GADA, IA-2A, and multiple antibodies. Taken together these observations suggest that HLA genes have a strong impact on the appearance of diabetes-associated autoantibodies both in first-degree relatives of affected children and in the general population. In patients with newly diagnosed disease IA-2A may be a more specific marker of beta-cell damage, whereas GADA might reflect a propensity to autoimmunity in general.

Antibody Formation↗

A linkage study of 12 IDDM susceptibility loci in the Finnish population.

BACKGROUND: HLA region is the major locus (IDDM1) of type 1 diabetes (T1D) susceptibility. It explains approximately 50% of the genetic background of T1D, indicating additional genetic determinants. Genome scans and candidate gene studies have generated several chromosomal candidate regions that may have a role in T1D development. METHODS: We tested 12 of these loci for linkage in 107 Finnish T1D multiplex families using 23 microsatellite markers and 2 SNPs. Families were stratified according to the HLA status and sharing at the DQB1 gene. RESULTS: We found no significant or suggestive MLS in our unstratified families outside the IDDM1 locus. The highest MLS was seen close to the IDDM9 region marker D3S3576 at 3q21-q25 (MLS=1.05). This marker also had a global p-value of 0.0032 (ETDT) in maternal transmissions. IDDM6 and 12q12-q15 region showed MLS=1.1 and MLS=1.3 respectively in HLA-DQB1*0302/x (x is not equal to HLA-DQB1*02) stratified families. IDDM12 showed MLS=2.0 in HLA-DQB1 identical sib pairs. Linkage at IDDM12 was supported by a global p-value of 0.0006 (uncorrected) in ETDT. For IDDM2, p-values of 0.028 and 0.009 were observed in ETDT with MspI-2221 SNP in unstratified and HLA-DQB1*0302/x-stratified families respectively. CONCLUSIONS: Our results are consistent with previous findings of linkage or association to T1D at IDDM2, IDDM6, IDDM9, IDDM12 and 12q12-q15 regions but do not unambiguously confirm them. A larger sample set is required to gain statistical power needed to confirm our findings in the Finnish population.

Chromosomes, Human↗