No change in type 2 diabetes prevalence in children and adolescents over 10 years: Update of a population-based survey in South Germany.

Objective of this study was to analyze prevalence changes in type 2 diabetes (T2D) among children and adolescents over the last 10 years. We performed a cross-sectional survey in Baden-Württemberg (BW), Germany, by using a written questionnaire and comparing these results with T2D prevalence data from the same area retrieved in 2004/2005. In 2016, 50 patients with T2D under 20 years of age were registered in BW, Germany, which corresponds to a prevalence rate of 2.42 per 100 000 (95% confidence interval [CI]: 1.75-3.09). The prevalence rate found in the same geographic area 10 years prior was 2.30 per 100 000 (95% CI: 1.70-2.90). Overall, 70% of T2D patients of this age group were treated by adult diabetologists. Concisely the prevalence of T2D in children and adolescents is still low in South Germany, remaining practically unchanged over the past decade.

[Diabetes mellitus at the interface between pediatric and adult medicine]. / Diabetes mellitus an der Schnittstelle von Pädiatrie und Erwachsenenmedizin.

Patients with chronic diseases manifesting in childhood, such as type 1 diabetes, need to make an optimal transition from pediatric to adult medical care. This or transitionis a challenge for patients and their treatment teams, since metabolic control is often unstable at this time of life. Additional factors like the social environment, as well as concomitant diseases, also need to be taken into account and often represent hurdles to optimal therapy. Transition is an important process to guarantee good self-management of diabetes therapy and good outcomes in the long term. This review provides an overview and recommendations on the topic of transition in diabetes.

Classifying insulin regimens--difficulties and proposal for comprehensive new definitions.

Modern insulin regimens for the treatment of type 1 diabetes are highly individualized. The concept of an individually tailored medicine accounts for a broad variety of different insulin regimens applied. Despite clear recommendations for insulin management in children and adolescents with type 1 diabetes there is little distinctiveness about concepts and the nomenclature is confusing. Even among experts similar terms are used for different strategies. The aim of our review--based on the experiences of the Hvidoere Study Group (HSG)--is to propose comprehensive definitions for current insulin regimens reflecting current diabetes management in childhood and adolescence. The HSG--founded in 1994--is an international group representing 24 highly experienced pediatric diabetes centers, from Europe, Japan, North America and Australia. Different benchmarking studies of the HSG revealed a broad variety of insulin regimens applied in each center, respectively. Furthermore, the understanding of insulin regimens has been persistently different between the centers since more than 20 yr. Not even the terms 'conventional' and 'intensified therapy' were used consistently among all members. Besides the concepts 'conventional' and 'intensified', several other terms for the characterization of insulin regimens are in use: Basal Bolus Concept (BBC), multiple daily injections (MDI), and flexible insulin therapy (FIT) are most frequently used, although none of these expressions is clearly or consistently defined. The proposed new classification for insulin management will be comprehensive, simple, and catchy. Currently available terms were included. This classification may offer the opportunity to compare therapeutic strategies without the currently existing confusion on the insulin regimen.

Seasonal variation in month of diagnosis in children with type 1 diabetes registered in 23 European centers during 1989-2008: little short-term influence of sunshine hours or average temperature.

BACKGROUND: The month of diagnosis in childhood type 1 diabetes shows seasonal variation. OBJECTIVE: We describe the pattern and investigate if year-to-year irregularities are associated with meteorological factors using data from 50 000 children diagnosed under the age of 15 yr in 23 population-based European registries during 1989-2008. METHODS: Tests for seasonal variation in monthly counts aggregated over the 20 yr period were performed. Time series regression was used to investigate if sunshine hour and average temperature data were predictive of the 240 monthly diagnosis counts after taking account of seasonality and long term trends. RESULTS: Significant sinusoidal pattern was evident in all but two small centers with peaks in November to February and relative amplitudes ranging from ± 11 to ± 38% (median ± 17%). However, most centers showed significant departures from a sinusoidal pattern. Pooling results over centers, there was significant seasonal variation in each age-group at diagnosis, with least seasonal variation in those under 5 yr. Boys showed greater seasonal variation than girls, particularly those aged 10-14 yr. There were no differences in seasonal pattern between four 5-yr sub-periods. Departures from the sinusoidal trend in monthly diagnoses in the period were significantly associated with deviations from the norm in average temperature (0.8% reduction in diagnoses per 1 °C excess) but not with sunshine hours. CONCLUSIONS: Seasonality was consistently apparent throughout the period in all age-groups and both sexes, but girls and the under 5 s showed less marked variation. Neither sunshine hour nor average temperature data contributed in any substantial way to explaining departures from the sinusoidal pattern.

Incidence and presentation of new-onset type 1 diabetes in children and adolescents from Germany during the COVID-19 pandemic 2020 and 2021: Current data from the DPV Registry.

AIMS: To determine whether the incidence of type 1 diabetes mellitus (T1D), autoantibody-negative diabetes, and diabetic ketoacidosis (DKA) at diabetes onset in 2020 and 2021 changed when compared to long-standing trends. METHODS: Our study is based on diabetes manifestation data of the 0.5-<18-year-old children/adolescents from the German multicenter Diabetes Prospective Follow-up Registry. Based on long-term pre-pandemic trends from 2011 to 2019, we estimated adjusted incidence rate ratios (IRR) for T1D and DKA, and prevalence rate ratios (PRR) regarding autoantibody status with 95 % confidence intervals (CI) for the years 2020 and 2021 (observed versus predicted rates), using multivariable negative binomial or beta-binomial regression, respectively. RESULTS: We analyzed data of 30,840 children and adolescents with new-onset T1D. The observed incidences were significantly higher than the predicted incidences (IRR2020 1.13 [1.08-1.19]; IRR2021 1.20 [1.15-1.26]). The prevalence of autoantibody-negative diabetes did not change (PRR2020 0.91 [0.75-1.10]; PRR2021 1.03 [0.86-1.24]). The incidence of DKA during the pandemic was higher than predicted (IRR2020 1.34 [1.23-1.46]; IRR2021 1.37 [1.26-1.49]). CONCLUSIONS: An increase in the incidences of T1D and DKA, but not of autoantibody-negative diabetes was observed during both pandemic years. Further monitoring and efforts for DKA prevention at onset are necessary.

Age-period-cohort modelling of type 1 diabetes incidence rates among children included in the EURODIAB 25-year follow-up study.

AIMS: Specific patterns in incidence may reveal environmental explanations for type 1 diabetes incidence. We aimed to study type 1 diabetes incidence in European childhood populations to assess whether an increase could be attributed to either period or cohort effects. METHODS: Nineteen EURODIAB centres provided single year incidence data for ages 0-14 in the 25-year period 1989-2013. Case counts and person years were classified by age, period and cohort (APC) in 1-year classes. APC Poisson regression models of rates were fitted using restricted cubic splines for age, period and cohort per centre and sex. Joint models were fitted for all centres and sexes, to find a parsimonious model. RESULTS: A total of 57,487 cases were included. In ten and seven of the 19 centres the APC models showed evidence of nonlinear cohort effects or period effects, respectively, in one or both sexes and indications of sex-specific age effects. Models showed a positive linear increase ranging from approximately 0.6 to 6.6%/year. Centres with low incidence rates showed the highest overall increase. A final joint model showed incidence peak at age 11.6 and 12.6 for girls and boys, respectively, and the rate-ratio was according to sex below 1 in ages 5-12. CONCLUSION: There was reasonable evidence for similar age-specific type 1 diabetes incidence rates across the EURODIAB population and peaks at a younger age for girls than boys. Cohort effects showed nonlinearity but varied between centres and the model did not contribute convincingly to identification of environmental causes of the increase.

Trends in childhood type 1 diabetes incidence in Europe during 1989-2008: evidence of non-uniformity over time in rates of increase.

AIMS/HYPOTHESIS: The aim of the study was to describe 20-year incidence trends for childhood type 1 diabetes in 23 EURODIAB centres and compare rates of increase in the first (1989-1998) and second (1999-2008) halves of the period. METHODS: All registers operate in geographically defined regions and are based on a clinical diagnosis. Completeness of registration is assessed by capture-recapture methodology. Twenty-three centres in 19 countries registered 49,969 new cases of type 1 diabetes in individuals diagnosed before their 15th birthday during the period studied. RESULTS: Ascertainment exceeded 90% in most registers. During the 20-year period, all but one register showed statistically significant changes in incidence, with rates universally increasing. When estimated separately for the first and second halves of the period, the median rates of increase were similar: 3.4% per annum and 3.3% per annum, respectively. However, rates of increase differed significantly between the first half and the second half for nine of the 21 registers with adequate coverage of both periods; five registers showed significantly higher rates of increase in the first half, and four significantly higher rates in the second half. CONCLUSIONS/INTERPRETATION: The incidence rate of childhood type 1 diabetes continues to rise across Europe by an average of approximately 3-4% per annum, but the increase is not necessarily uniform, showing periods of less rapid and more rapid increase in incidence in some registers. This pattern of change suggests that important risk exposures differ over time in different European countries. Further time trend analysis and comparison of the patterns in defined regions is warranted.

Increased hospitalizations and death in patients with ESRD secondary to lupus.

BACKGROUND: Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect almost any organ system, including the kidneys. Using a large national dataset, our goal was to compare the morbidity as measured by hospitalization and mortality rates between hemodialysis patients with end-stage renal disease (ESRD) secondary to SLE to those with ESRD due to other causes. METHODS: The risk of hospitalization was calculated by Poisson regression with clustering for repeated measures using the United States Renal Data System (USRDS) Hospitalization Analytic File in strata of pediatric and adult patients. Cox proportional hazard ratio was used to assess the mortality risk in hospitalized patients. Subjects were censored at transplantation or end of follow-up. RESULTS: Adult patients with ESRD secondary to SLE were hospitalized more frequently than other adults (incidence rate ratio (IRR): 1.43, 95% confidence interval (CI): 1.15-1.77) and had a higher risk of death (hazard ratio (HR): 1.89, 95% CI: 1.66-2.5). Mortality was higher in hospitalized pediatric patients with SLE compared to pediatric patients with other causes of ESRD (HR: 2.01, 95% CI: 1.75-2.31) and adults with SLE (HR: 2.05, 95% CI: 1.79-2.34). CONCLUSION: Our study demonstrates that there is a trend toward increased hospitalization rates in pediatric and adult patients with SLE. Among these hospitalized patients with SLE, there is an increased risk of death due to cardiovascular disease.

[Frequency and influencing factors of ketoacidosis at diabetes onset in children and adolescents--a long-term study between 1995 and 2009]. / Häufigkeit und Einflussfaktoren der Ketoazidose bei Diabetesmanifestation im Kindes- und Jugendalter--eine Langzeitstudie von 1995 bis 2009.

BACKGROUND: Diabetic ketoacidosis (DKA) is a frequent acute complication at onset of type 1 diabetes. It is assumed that increased public awareness about diabetes symptoms may reduce DKA rate at diabetes onset. To investigate the time-dependent trend in DKA prevalence we analysed the frequency and determinants of DKA at disease onset over 15 years in pediatric patients. PATIENTS AND METHODS: The prevalence of DKA at disease onset was analysed in individuals aged ≤18 years treated for the first time from 1995-2009 within 7 days after diagnosis in pediatric centers. Simple and multiple logistic regression analysis was performed to investigate influencing factors on DKA prevalence. Change of the probability of ketoacidosis over years were modelled in the logistic regression as linear trend. RESULTS: 16 562 individuals from 170 institutions were studied with a mean age of 9.2 ± 4.2 years. DKA (pH <7.3) was present in 20.8% of patients without a significant trend between 1995 and 2009 (p=0.222). DKA prevalence was higher in children ≤5 years (26.3%) and in the age group 10-15 years (21.7%) than in individuals aged 5-10 years (16.4%) and 15-18 years (16.9%, p<0.001). Girls had DKA more often than boys (21.2% vs. 19.3%, p=0.002). DKA frequency was increased in individuals with migration background (26.5% vs. 19.2%, p<0.001). CONCLUSIONS: DKA prevalence at diabetes onset was constant at about 21% during the last 15 years. Very young children, pubertal adolescents, girls and individuals with migration background are at higher risk for DKA at diagnosis. To prevent DKA earlier diagnosis of type 1 diabetes is warranted especially in these patient groups.

Nonadherence consensus conference summary report.

This report is a summary of a 'Consensus Conference' on nonadherence (NA) to immunosuppressants. Its aims were: (1) to discuss the state-of-the-art on the definition, prevalence and measurement of NA, its risk factors and impact on clinical and economical outcomes and interventions and (2) to provide recommendations for future studies. A two-day meeting was held in Florida in January 2008, inviting 66 medical and allied health adherence transplant and nontransplant experts. A scientific committee prepared the meeting. Consensus was reached using plenary and interactive presentations and discussions in small break-out groups. Plenary presenters prepared a summary beforehand. Break-out group leaders initiated discussion between the group members prior to the meeting using conference calls and e-mail and provided a summary afterward. Conclusions were that NA: (a) is more prevalent than we assume; (b) is hard to measure accurately; (c) tends to confer worse outcomes; (d) happens for a number of reasons, and system-related factors including the patient's culture, the healthcare provider and the setting and (e) it is not currently known how to improve adherence. This consensus report provided some roadmaps for future studies on this complicated, multifaceted problem.

Continuous rise in incidence of childhood Type 1 diabetes in Germany.

AIMS: To assess the incidence and the trend in incidence of Type 1 diabetes (T1DM) in children and adolescents < 15 years of age in Baden-Württemberg (BW), Germany. METHODS: BW is Germany's third largest federal state. All 31 paediatric departments in BW and one diabetes centre participated in the study. Case registration was done according to the EURODIAB criteria. The degree of ascertainment was 97.2%. RESULTS: From 1987 to 2003, the age- and sex-standardized incidence rate was 14.1/100,000 per year [95% confidence interval (CI) 13.7, 14.6, n = 4017]. The estimated annual increase in incidence was 3.8% (95% CI 1.1, 6.6). Compared with the first years of our registry, the current mean number of new cases of T1DM has doubled (1987-1989, n = 153; 2000-2003, n = 302). Generally, the highest rise in incidence occurred in the youngest age group of 0-4-year-old patients (5.8%; 95% CI 2.5, 9.3), followed by the age groups 5-9 (3.4%; 95% CI 0.8, 6.0) and 10-14 (2.7%; 95% CI 0.3, 5.1). CONCLUSIONS: In Germany, the number of children and adolescents with new-onset T1DM has been rising at a faster pace than expected. A distinct shift to younger age at onset has been observed in Germany.

Novel mitochondrial DNA length variants and genetic instability in a family with diabetes and deafness.

We have identified two locations with novel multiplasmic length variants in the mitochondrial DNA of a family with diabetes and deafness. At nt568 in the D-loop, the 6-bp polycytidine tract was found to be variable in length up to a total of 12 residues. A second region with length variants was found at nt8281 in the intergenic COII-tRNA(Lys) region, which consists of two copies of the 9-bp repeat CCCCCTCTA. Only the second repeat occurs in a heteroplasmic C(9-14)A form with both T residues largely deleted. In addition, the mtDNA contained a number of new homoplasmic point mutations. Both length variants are stably inherited in a maternal way with no major changes in their length distribution. In contrast, during culture of fibroblasts from the proband the average length of the polycytidine tracts is increased at both locations indicating a fibroblast-specific genetic instability. Cybrid cells containing mtDNA from the proband proliferate less efficient than cybrids with wild-type mtDNA in co-culture experiments, suggesting functional consequences of the mtDNA length variants or the additional homoplasmic point mutations. Since oxygen consumption was not severely affected, these mutation seem less detrimental for mitochondrial function than the A3243G diabetogenic mutation and most other pathogenic mtDNA mutations. The contribution of mtDNA length variants to the phenotype of members of this family is discussed.

The weaver mouse gain-of-function phenotype of dopaminergic midbrain neurons is determined by coactivation of wvGirk2 and K-ATP channels.

The phenotype of substantia nigra (SN) neurons in homozygous weaver (wv/wv) mice was studied by combining patch-clamp and single-cell RT-multiplex PCR techniques in midbrain slices of 14-d-old mice. In contrast to GABAergic SN neurons, which were unaffected in homozygous weaver mice (wv/wv), dopaminergic SN neurons possessed a dramatically altered phenotype with a depolarized membrane potential and complete loss of spontaneous pacemaker activity. The gain-of-function phenotype was mediated by a large, nonselective membrane conductance exclusively present in (wv/wv) dopaminergic SN neurons. This constitutively activated conductance displayed a sensitivity to external QX-314 (IC(50) = 10.6 microM) very similar to that of heterologously expressed wvGirk2 channels and was not further activated by G-protein stimulation. Single-cell Girk1-4 expression profiling suggested that homomeric Girk2 channels were present in most dopaminergic SN neurons, whereas Girk2 was always coexpressed with other Girk family members in GABAergic SN neurons. Surprisingly, acute QX-314 inhibition of wvGirk2 channels did not induce wild-type-like pacemaker activity but instead caused membrane hyperpolarization. Additional application of a blocker of ATP-sensitive potassium channels (100 microM tolbutamide) induced wild-type-like pacemaker activity. We conclude that the gain-of-function weaver phenotype of dopaminergic substantia nigra neurons is mediated by coactivation of wvGirk2 and SUR1/Kir6. 2-mediated ATP-sensitive K(+) channels. We also show that in contrast to wild-type neurons, all (wv/wv) dopaminergic SN neurons expressed calbindin, a calcium-binding protein that marks dopaminergic SN neurons resistant to neurodegeneration. The identification of two ion channels that in concert determine the weaver phenotype of surviving calbindin-positive dopaminergic SN neurons will help to understand the molecular mechanisms of selective neurodegeneration of dopaminergic SN neurons in the weaver mouse and might be important in Parkinson's disease.

Incidence of IDDM in German children aged 0-14 years. A 6-year population-based study (1987-1993)

OBJECTIVE: Generally accepted data on the incidence of childhood diabetes in Germany have not been available up to now. To register the total number of newly diagnosed cases in Baden-Wuerttemberg (a federal state in southwest Germany), data on 1,160 children were retrospectively collected for the years 1987-1993. RESEARCH DESIGN AND METHODS: Hospital records were the primary data source. There were 32 hospital units in Baden-Wuerttemberg included in this study. A secondary independent data source was a questionnaire circulated among the patients' association, Deutscher Diabetiker Bund. Case definition was done according to criteria EURODIAB ACE, a collaborative European study set up to assess the incidence of childhood diabetes. The degree of ascertainment was 96.2%, using the capture-mark-recapture method. The study includes a population at risk, entailing 1.5 million children, corresponding to 12.3% of all German children. RESULTS: The incidence was found to be 11.6/100,000 (95% CI 10.9-12.2) for children aged 0-14 years. There was no significant difference between the incidence rates of boys and girls. Seasonal variation was observed, with cases increasing between November and February and incidence increasing with age. Peaks were found in early childhood (3-4 years of age) and prepuberty (10-12 years of age). There was marked geographical variation that did not correlate significantly with population density. CONCLUSIONS: For the first time, internationally comparable data on the incidence of diabetes in children up to 15 years of age are available for Germany. The yearly incidence of 11.6/100,000 proved to be much higher than assumed so far.

For-profit versus not-for-profit dialysis care for children with end stage renal disease.

OBJECTIVE: Over the last 2 decades, for-profit dialysis units have become the most common providers of renal replacement therapy for adults with end stage renal disease (ESRD) and have had an increasing role in the dialysis of children. We undertook a study to determine whether dialysis facility profit status influences the choice of dialysis therapy in the pediatric population. DESIGN: Cross-sectional study of national data from the Health Care Financing Administration. SETTING: Free-standing and hospital-based outpatient dialysis facilities in the United States. PATIENTS: A total of 1568 children and adolescents (

Immunization guidelines for pediatric renal disease.

It is imperative that pediatric nephrologists monitor the immunization status of pediatric chronic renal insufficiency, dialysis and transplantation patients closely to reduce the risk of vaccine-preventable disease. Pediatric patients with chronic renal insufficiency and those on dialysis should receive all the standard immunizations according to the schedule as deliniated by the Red Book. In addition to these standard vaccines, these patients will also benefit from influenza and pneumococcal vaccine. Pediatric renal transplant recipients should also be immunized with standard and special vaccines; however, all live viral vaccines should be avoided in this population. Because patients with renal disease may not respond optimally to all immunizations, it is important to study antibody response to MMR and varicella in patients before transplantation. If these patients are unprotected, they should be immunized before transplantation. It seems that pediatric dialysis and transplantation patients may not respond optimally to hepatitis B vaccine. Therefore, if at all possible, this vaccine should be administered before these therapies. Doubling the recommended dose of hepatitis B vaccine may improve response. Antibody levels to hepatitis B should be monitored every other year, and this vaccine should be readministered when the antibody level decreases to less than 10 mIU/mL. Hopefully the morbidity and mortality associated with vaccine-preventable disease can be reduced in this population by ensuring that pediatric patients with chronic renal disease are adequately immunized.

Does growth retardation indicate suboptimal clinical care in children with chronic renal disease and those undergoing dialysis?

Growth failure is an important problem for children with end-stage renal disease (ESRD). Patients receiving replacement therapy for longstanding renal failure since childhood are likely to report dissatisfaction with certain aspects of their lives, especially with final adult height. Additionally, recent data suggest that growth failure in children with ESRD is associated with adverse clinical outcomes, including more frequent hospitalizations, and increased mortality. Although poor growth is unlikely to be the cause of this increased morbidity, growth failure may be a marker for a group of patients at high risk of adverse events. In this review, the authors describe the prevalence of growth retardation in children in the US with chronic renal disease, and present recent data on morbidity associated with growth failure. After reviewing published reports documenting available strategies to optimize growth, the authors conclude that despite vigilance and aggressive clinical management, a subset of children with long-term renal insufficiency and ESRD may still have poor linear growth. A discussion of "optimal care" leads one to consider evidence of current variability in the management of growth retardation in ESRD, and the strengths and limitations of developing practice guidelines to optimize growth in this population.

Does greater pediatric experience influence treatment choices in chronic disease management? Dialysis modality choice for children with end-stage renal disease.

OBJECTIVE: To determine whether treatment choice for children with end-stage renal disease varies with greater pediatric experience at the dialysis facility. DESIGN: National cross-sectional study. SETTING: Outpatient dialysis facilities throughout the United States. PATIENTS: All children (age, < or = 19 years) undergoing dialysis in 1990, identified using the Medicare End-stage Renal Disease registry (1990 facility survey and quarterly dialysis records). OUTCOME MEASURES: The odds of receiving peritoneal dialysis vs hemodialysis according to the pediatric experience of the facility. "Pediatric experience" for dialysis facilities was defined as the number of patients 19 years old or younger divided by the total number of patients treated at that facility. Adjustment, using multiple logistic regression, was made for differences in age, sex, cause and duration of end-stage renal disease, income, education, and facility characteristics. RESULTS: In 1990, there were 1256 patients 19 years old or younger who underwent a single-treatment modality at a single facility for most of the year. Sixty-three percent (790/ 1256) were treated at facilities with fewer than 5% of patients younger than 19 years. Thirty-six percent were treated at centers with less than 1% of pediatric patients. In a multivariate analysis, pediatric experience in a facility was independently associated with the use of peritoneal dialysis in children. Children treated at facilities with more than 10% pediatric patients were 60% more likely to be treated with peritoneal dialysis rather than hemodialysis compared with children treated at facilities with fewer than 1% of pediatric patients, even after controlling for patient age, race, income, education, cause and duration of end-stage renal disease, and facility characteristics such as hospital-based vs independent unit and for-profit vs not-for-profit status (odds ratio, 1.6; 95% confidence interval, 1.1-2.3). CONCLUSIONS: Children receiving care at dialysis facilities that have greater experience with pediatric patients are more likely to receive peritoneal dialysis than hemodialysis, a therapy with recognized clinical benefits for children that is inherently less resource intensive than is hemodialysis.

Preretinopic changes in the colour vision of juvenile diabetics.

AIMS: To examine the colour vision of juvenile patients suffering from diabetes mellitus without retinopathy in relation to metabolic and ophthalmic state. METHODS: Metameric matches, both Rayleigh (red/green) and Moreland (blue/green) were used to test the colour vision yearly of 10 juvenile patients. The patients were monitored over 4 years, and during the final year, their blood glucose level was determined directly after testing colour vision. An ophthalmic examination was performed on the day of colour vision testing and blood and urine were analysed regularly throughout the 4 years. Their results are compared with an aged matched control group of 20 subjects, seven of whom were retested after 9-16 months. RESULTS: After 4 years, the colour vision results show an enlarged matching range for the Moreland match, as well as a smaller increase in the matching range for the Rayleigh match. No significant correlation was found between blood glucose at the time of testing and any of the variables measured. CONCLUSION: The pattern of colour vision deficits in metameric matching shown by juvenile diabetics is consistent with postreceptoral alterations of the inner retina, at this preretinopic stage of disease. Duration of diabetes is correlated with both colour vision changes and morphological alteration of the retina.

Development of brightness matching and colour vision deficits in juvenile diabetics.

We studied hue discrimination and brightness matching throughout the spectrum in ten juvenile patients suffering from diabetes mellitus (Type I) with no (eight patients) or mild (two patients) retinopathy. In addition, the FM 100-Hue test was performed. The data were collected once every year over 5 years. Over the 5 years, the diabetics show a continual change in the shape of their brightness matching function. Wavelength discrimination ability remains quite stable with time at the long end of the spectrum but is variable at short wavelengths. FM-100 error scores remain similar over the period tested, at a level slightly higher than that of a control group. Additional experiments show that the sensitivity of the S-cone in the diabetic group is similar to that of controls. The results can be explained by an early relative reduction in the sensitivity of post-receptoral processes in juvenile diabetics.