Modification Effects of Albuminuria on the Association Between Kidney Function and Development of Anemia in Diabetes

CONTEXT

Previous studies failed to adjust for estimated glomerular filtration rate (eGFR) in evaluating the association between albuminuria and anemia development, and we aimed to investigate whether albuminuria independently affects anemia development.

METHODS

We conducted a retrospective cohort study and retrospectively identified adults with diabetes from a Japanese nationwide clinical database (JMDC, Tokyo, Japan). To assess the modification effects of albuminuria on the association between eGFR and anemia development, we estimated prevalence of anemia, defined as hemoglobin < 13 g/dL in men and < 12 g/dL in women, using a modified Poisson regression and marginal standardization form of predictive margins, stratified by albuminuria severity after adjusting for eGFR. Hence, we revealed at which eGFR level this modification effect appeared and the extent to which this modification effect increased the prevalence of anemia.

RESULTS

We identified 327 999 data points from 48 056 individuals [normoalbuminuria: 186 472 (56.9%), microalbuminuria: 107 170 (32.7%), and macroalbuminuria: 34 357 (10.5%)]. As eGFR declined, anemia prevalence increased. Albuminuria severity modified this association induced by decreased eGFR among individuals with eGFR <30 mL/min/1.73 m2 after adjusting for multivariable factors, including age, sex, comorbidities, and medication use. Compared with the normoalbuminuric group, the macroalbuminuric group had a 5% to 20% higher anemia prevalence among individuals with eGFR of <30 mL/min/1.73 m2.

CONCLUSION

We revealed that the severity of albuminuria modified the association between eGFR and anemia development among individuals with eGFR <30 mL/min/1.73 m2, highlighting the modification effect of albuminuria on the association between kidney function and anemia development in diabetes.

Cancer biology in diabetes update: Focusing on antidiabetic drugs

The association of type 2 diabetes with certain cancer risk has been of great interest for years. However, the effect of diabetic medications on cancer development is not fully understood. Prospective clinical trials have not elucidated the long-term influence of hypoglycemic drugs on cancer incidence and the safety for cancer-bearing patients with diabetes, whereas numerous preclinical studies have shown that antidiabetic drugs could have an impact on carcinogenesis processes beyond the glycemic control effect. Because there is no evidence of the safety profile of antidiabetic agents on cancer biology, careful consideration would be required when prescribing any medicines to patients with diabetes and existing tumor. In this review, we discuss the potential influence of each diabetes therapy in cancer 'initiation', 'promotion' and 'progression'.

New diagnostic criteria (2023) for slowly progressive type 1 diabetes (SPIDDM): Report from Committee on Type 1 Diabetes in Japan Diabetes Society (English version)

The diagnostic criteria for slowly progressive type 1 diabetes (slowly progressive insulin-dependent diabetes mellitus; SPIDDM) have been revised by the Committee on Type 1 Diabetes of the Japan Diabetes Society. All of the following three criteria must be met for "a definitive diagnosis of SPIDDM": (1) presence of anti-islet autoantibodies at some point in time during the disease course; (2) absence of ketosis or ketoacidosis at the diagnosis of diabetes with no requirement of insulin treatment to correct hyperglycemia immediately after diagnosis in principle; and (3) gradual decrease of insulin secretion over time, with insulin treatment required at more than 3 months after diagnosis, and presence of severe endogenous insulin deficiency (fasting serum C-peptide immunoreactivity < 0.6 ng/mL) at the last observed point in time. When a patient fulfills the only (1) and (2), but not (3), he/she is diagnosed with "SPIDDM (probable)" because the diabetes is non-insulin-dependent state.

Prevalence and characteristics of diabetic symmetric sensorimotor polyneuropathy in Japanese patients with type 2 diabetes: the Japan Diabetes Complication and its Prevention Prospective study (JDCP study 10)

Aim/introduction

This study aims to investigate the prevalence and characteristics of diabetic symmetric sensorimotor polyneuropathy (DSPN) in patients with type 2 diabetes registered in the Japan Diabetes Complication and its Prevention Prospective (JDCP) study.

Materials and methods

In the study, 6338 patients with diabetes who had been treated by diabetes specialists were registered in 2007-2009. Of these, patients with type 2 diabetes who could be evaluated for DSPN were analyzed using t test, chi-square test, and logistic regression analyses. DSPN was diagnosed using the Simple Diagnostic Criteria for Diabetic Polyneuropathy proposed by the Diabetic Neuropathy Study Group in Japan.

Results

Of the total participants, 5451 patients (mean age 61.4 years old and duration of diabetes 10.8 years) were analyzed. Based on the criteria, 35.8% of patients were diagnosed with DSPN. The prevalence of sensory symptoms was 25.8%. The following factors increased risk for DSPN: age [odds ratio (OR) 1.57, 95% confidence intervals (CI) 1.42-1.73], duration of diabetes (OR 1.32, 95% CI 1.21-1.43), body mass index (OR 1.19, 95% CI 1.09-1.30), systolic blood pressure (OR 1.06, 95% CI 1.01-1.10), hemoglobin A1c (OR 1.15, 95% CI 1.09-1.22), biguanides (OR 1.22, 95% CI 1.06-1.39), and insulin therapy (OR 1.59, 95% CI 1.36-1.84). The following factors decreased risk for DSPN: total cholesterol (OR 0.98, 95% CI 0.96-1.00) and exercise therapy (OR 0.85, 95% CI 0.73-0.98).

Conclusions

The baseline survey clarified the prevalence and characteristics of DSPN in Japanese patients with type 2 diabetes. The survey also revealed the risk factors of DSPN.

Novel time-resolved reporter mouse reveals spatial and transcriptional heterogeneity during alpha cell differentiation

AIMS/HYPOTHESIS

Glucagon-expressing pancreatic alpha cells have attracted much attention for their plasticity to transdifferentiate into insulin-producing beta cells; however, it remains unclear precisely when, and from where, alpha cells emerge and what regulates alpha cell fate. We therefore explored the spatial and transcriptional heterogeneity of alpha cell differentiation using a novel time-resolved reporter system.

METHODS

We established the mouse model, 'Gcg-Timer', in which newly generated alpha cells can be distinguished from more-differentiated cells by their fluorescence. Fluorescence imaging and transcriptome analysis were performed with Gcg-Timer mice during the embryonic and postnatal stages.

RESULTS

Fluorescence imaging and flow cytometry demonstrated that green fluorescence-dominant cells were present in Gcg-Timer mice at the embryonic and neonatal stages but not after 1 week of age, suggesting that alpha cell neogenesis occurs during embryogenesis and early neonatal stages under physiological conditions. Transcriptome analysis of Gcg-Timer embryos revealed that the mRNAs related to angiogenesis were enriched in newly generated alpha cells. Histological analysis revealed that some alpha cells arise close to the pancreatic ducts, whereas the others arise away from the ducts and adjacent to the blood vessels. Notably, when the glucagon signal was suppressed by genetic ablation or by chemicals, such as neutralising glucagon antibody, green-dominant cells emerged again in adult mice.

CONCLUSIONS/INTERPRETATION

Novel time-resolved analysis with Gcg-Timer reporter mice uncovered spatiotemporal features of alpha cell neogenesis that will enhance our understanding of cellular identity and plasticity within the islets.

DATA AVAILABILITY

Raw and processed RNA sequencing data for this study has been deposited in the Gene Expression Omnibus under accession number GSE229090.

Heterogeneity of adipose tissue-resident macrophages-beyond M1/M2 paradigm

Adipose tissue-resident macrophages (ATMs) are reported to be important for maintaining adipose tissue remodeling and homeostasis. ATMs were classified for the first time in 2007 into the M1 and M2 types. This theory suggests that in the non-obese adipose tissue, the anti-inflammatory, alternatively activated macrophages (AAMs) predominate, and regulate tissue homeostasis, remodeling, and insulin sensitivity. On the other hand, classically activated M1-type macrophages increase rapidly in obesity, secrete inflammatory cytokines, such as TNFα and IL-6, and induce insulin resistance. In recent years, experimental findings that cannot be explained by this theory have been clarified one after another and the theory is being reconsidered. In this review, based on recent findings, we summarize reports on the novel metabolic regulatory functions of ATMs beyond the M1/M2 paradigm.

Dietary intake and physical activity in Japanese patients with type 2 diabetes: the Japan Diabetes Complication and its Prevention prospective study (JDCP study 8)

Medical nutrition therapy and exercise therapy are the cornerstones of treatment for patients with type 2 diabetes; however, there has not been a nationwide study on the actual dietary intake and physical activity status of patients since the 2000s. We aimed to clarify this in Japanese patients with type 2 diabetes using data from the Japan Diabetes Complication and its Prevention prospective (JDCP), a nationwide study launched in 2007. A total of 1992 patients with type 2 diabetes, aged 40-75 years, completed either the Brief-type, self-administered Diet History Questionnaire (1643 patients) or International Physical Activity Questionnaire (1834 patients), and their data were analyzed in this study. Mean daily energy intake for all participants was 1686.8 kcal/day, and the mean proportions of carbohydrate, protein, and fat comprising total energy intake were 60.2, 16.2, and 23.6%, respectively. The patients in this study had similar energy and nutrient intake status to patients in the 1996 Japan Diabetes Complications Study; however, Japanese patients still had higher carbohydrate and lower fat consumption than patients with diabetes in Western countries. The physical activity questionnaire reported that 31.0% of patients did not have exercise habits; this was particularly noticeable in female patients and patients under the age of 65. BMI increased from 22.7 to 24.1 kg/m² in men and 23.2 to 24.8 kg/m² in women from 1996 to 2007, respectively. Further research is required to investigate how dietary intake and physical activity associates with the risk of developing complications in type 2 diabetes patients.

Different impacts of metabolic profiles on future risk of cardiovascular disease between diabetes with and without established cardiovascular disease: the Japan diabetes complication and its prevention prospective study 7 (JDCP study 7)

AIMS

Most risk calculators that predict future cardiovascular disease (CVD) by baseline profiles are originally developed for primary prevention, but some studies applied the calculators to secondary prevention. We compared the impact of baseline profiles on the future CVD risk between patients with diabetes with and without a CVD history.

METHODS

We analyzed a multicenter prospective cohort of 6338 Japanese patients with diabetes aged 40-74 years, including those with (n = 634) and without a CVD history (n = 5704). The future risk of CVD was investigated using the competing risk model, with adjustment for non-cardiovascular mortality.

RESULTS

During the median follow-up of 6.9 years, 413 CVD events were observed. The 8-year cumulative incidence rates of CVD were 21.5% and 7.2% in patients with and without a CVD history, respectively. A higher systolic blood pressure and lower high-density lipoprotein cholesterol levels were independently associated with a future CVD risk in patients without a CVD history (both P < 0.05), whereas they were not associated in those with a CVD history. The P values for interaction were 0.040 and 0.005, respectively. The male sex, an older age, a longer duration of diabetes, higher hemoglobin A1c levels, and higher low-density lipoprotein cholesterol levels were common independent risk factors regardless of CVD history (all P < 0.05).

CONCLUSIONS

The prognostic impact of metabolic profiles on CVD risk would not be identical between patients with and without a CVD history, suggesting that it might be inappropriate to apply CVD risk calculators developed for primary prevention to patients with a CVD history.

Association between nutritional guidance or ophthalmological examination and discontinuation of physician visits in patients with newly diagnosed diabetes: A retrospective cohort study using a nationwide database

AIMS/INTRODUCTION

Discontinuation of diabetes care has been studied mostly in patients with prevalent diabetes and not in patients with newly diagnosed diabetes, whose dropout risk is highest. Because enrolling patients in a prospective study will influence adherence, we retrospectively examined whether guideline-recommended practices, defined as nutritional guidance or ophthalmological examination, can prevent patient discontinuation of diabetes care after its initiation.

MATERIALS AND METHODS

We retrospectively identified adults with newly screened diabetes during checkups using a large Japanese administrative claims database (JMDC, Tokyo, Japan) that contains laboratory data and lifestyle questionnaires. We defined discontinuation of physician visits as a follow-up interval exceeding 6 months. We divided the patients into those who received guideline-recommended practices (nutritional guidance or ophthalmology consultation) within the same month as the first visit and those who did not. We calculated propensity scores and carried out inverse probability of treatment weighting analyses to compare discontinuation between the two groups.

RESULTS

We identified 6,508 patients with at least one physician consultation for diabetes care within 3 months after their checkup, including 4,574 patients without and 1,934 with guideline-recommended practices. After inverse probability of treatment weighting, patients with guideline-recommended practices had a significantly lower proportion of discontinuation than those without (17.2% vs 21.8%; relative risk 0.79, 95% confidence interval 0.69-0.91).

CONCLUSIONS

This study is the first to show that after adjustment for both patient and healthcare provider factors, guideline-recommended practices within the first month of physician consultation for diabetes care can decrease subsequent discontinuation of physician visits in patients with newly diagnosed diabetes.

Effect of a Multifactorial Intervention on Fracture in Patients With Type 2 Diabetes: Subanalysis of the J-DOIT3 Study

AIMS

To evaluate the effects of an intensified multifactorial intervention and patient characteristics on the incidence of fractures comorbid with type 2 diabetes.

METHODS

Fracture events were identified and analyzed among adverse events reported in the J-DOIT3 study, a multicenter, open-label, randomized, parallel-group trial that was conducted in Japan, in which patients with type 2 diabetes were randomly assigned to receive conventional therapy for glucose, blood pressure, and lipids (targets: HbA1c < 6.9%, blood pressure <130/80 mm Hg, LDL-cholesterol <120mg/dL) or intensive therapy (HbA1c < 6.2%, blood pressure <120/75 mm Hg, LDL-cholesterol <80mg/dL) (ClinicalTrials.gov registration no. NCT00300976).

RESULTS

The cumulative incidence of fractures did not differ between those receiving conventional therapy and those receiving intensive therapy (hazard ratio (HR) 1.15; 95% CI, 0.91-1.47; P = 0.241). Among the potential risk factors, only history of smoking at baseline was significantly associated with the incidence of fractures in men (HR 1.96; 95% CI, 1.04-3.07; P = 0.038). In contrast, the incidence of fractures in women was associated with the FRAX score [%/10 years] at baseline (HR 1.04; 95% CI, 1.02-1.07; P < 0.001) and administration of pioglitazone at 1 year after randomization (HR 1.59; 95% CI, 1.06-2.38; P = 0.025).

CONCLUSIONS

Intensified multifactorial intervention may be implemented without increasing the fracture risk in patients with type 2 diabetes. The fracture risk is elevated in those with a history of smoking in men, whereas it is predicted by the FRAX score and is independently elevated with administration of pioglitazone in women.

NFIA differentially controls adipogenic and myogenic gene program through distinct pathways to ensure brown and beige adipocyte differentiation

The transcription factor nuclear factor I-A (NFIA) is a regulator of brown adipocyte differentiation. Here we show that the C-terminal 17 amino acid residues of NFIA (which we call pro#3 domain) are required for the transcriptional activity of NFIA. Full-length NFIA—but not deletion mutant lacking pro#3 domain—rescued impaired expression of PPARγ, the master transcriptional regulator of adipogenesis and impaired adipocyte differentiation in NFIA-knockout cells. Mechanistically, the ability of NFIA to penetrate chromatin and bind to the crucial Pparg enhancer is mediated through pro#3 domain. However, the deletion mutant still binds to Myod1 enhancer to repress expression of MyoD, the master transcriptional regulator of myogenesis as well as proximally transcribed non-coding RNA called ^DRReRNA, via competition with KLF5 in terms of enhancer binding, leading to suppression of myogenic gene program. Therefore, the negative effect of NFIA on the myogenic gene program is, at least partly, independent of the positive effect on PPARγ expression and its downstream adipogenic gene program. These results uncover multiple ways of action of NFIA to ensure optimal regulation of brown and beige adipocyte differentiation.

Obesity and its complications including type 2 diabetes are growing concerns worldwide. While white adipocytes generally store energy in the form of lipid, classical brown and cold- or β-adrenergic stimulation-induced beige adipocytes dissipate chemical energy in the form of heat through uncoupling protein-1 (Ucp1). Since the re-discovery of human brown and beige adipocytes, it has been considered a promising target for the treatment of obesity. During mesenchymal development, not only activation of brown/beige adipocyte gene program but also repression of muscle gene program is required to achieve thermogenic adipocyte differentiation. Previously, we identified the transcription factor nuclear factor I-A (NFIA) as a regulator of brown adipocyte differentiation. Here we show that the C-terminal 17 amino acid residues of NFIA, which we call pro#3 domain, is required for activation of adipocyte differentiation. However, the deletion mutant which lacks this domain is still able to suppress muscle gene program by repressing the expression of Myod1, which encode the master transcriptional regulator of myogenesis, MyoD. We demonstrate that NFIA activates adipogenesis and also “actively” suppresses myogenesis through distinct molecular pathways to ensure brown and beige adipocyte differentiation.

Incidence of severe hypoglycemia and its association with serum adiponectin in Japanese patients with type 1 and insulin-treated type 2 diabetes: The Fukuoka Diabetes Registry

AIMS/INTRODUCTION

The incidence of severe hypoglycemia and its risk factors including an insulin-sensitizing adipokine, adiponectin, were prospectively investigated in Japanese patients with type 1 or insulin-treated type 2 diabetes.

MATERIALS AND METHODS

A total of 207 participants with type 1 diabetes (mean age 55 years) and 1,396 with insulin-treated type 2 diabetes (mean age 65 years) from the local diabetes registry were followed for 5 years (follow-up rate 99%). Severe hypoglycemia was defined as events requiring the assistance of others for recovery from hypoglycemia.

RESULTS

The incidence of severe hypoglycemia was 9.2 per 100 person-years in those with type 1 diabetes, and 2.3 per 100 person-years in those with insulin-treated type 2 diabetes, respectively. For type 1 diabetes, the risk was significant in those with a history of severe hypoglycemia within the previous year, slow eating and higher serum adiponectin (the highest vs the lowest in quartile hazard ratio 2.36, 95% confidence interval 1.22-4.69). For insulin-treated type 2 diabetes, the risk included age ≥65 years, history of severe hypoglycemia within the previous year, alcohol consumption ≥60 g/day, larger insulin dose and higher serum adiponectin (the highest vs the lowest in quartile, hazard ratio 2.95, 95% confidence interval 1.22-4.69). For all participants, the incidence of severe hypoglycemia increased along with serum adiponectin (age- and sex-adjusted hazard ratio 1.65 per 1 standard deviation increase of log serum adiponectin, 95% confidence interval 1.45-1.87).

CONCLUSIONS

The incidence of severe hypoglycemia was prospectively determined, and the association between severe hypoglycemia and higher serum adiponectin was observed in Japanese patients with type 1 and insulin-treated type 2 diabetes.

Prevalence of albuminuria and renal dysfunction, and related clinical factors in Japanese patients with diabetes: The Japan Diabetes Complication and its Prevention prospective study 5

AIMS/INTRODUCTION

To clarify the prevalence of albuminuria and renal dysfunction, and related factors in Japanese patients with diabetes, we analyzed the baseline data of the Japan Diabetes Complication and its Prevention prospective study.

MATERIALS AND METHODS

We used the data of 355 patients with type 1 diabetes and 5,194 patients with type 2 diabetes to evaluate the prevalence of albuminuria and renal dysfunction, and related factors. A binomial logistic regression analysis was used to investigate independent contributing factors for estimated glomerular filtration rate <60 mL/min/1.73 m2 or albuminuria.

RESULTS

The prevalence of microalbuminuria and macroalbuminuria was 15.2% (54/355) and 3.1% (11/355) in type 1 diabetes patients, and 25.0% (1,298/5,194) and 5.1% (265/5,194) in type 2 diabetes patients, respectively. The proportion of renal dysfunction (estimated glomerular filtration rate <60 mL/min/1.73 m2 ) was 9.9% (35/355) in type 1 diabetes patients, and 15.3% (797/5,194) in type 2 diabetes patients. The proportion of patients with renal dysfunction with normoalbuminuria was 7.3% (26/355) for type 1 diabetes patients, and 9.0% (467/5,194) for type 2 diabetes patients. The factors related to albuminuria in type 2 diabetes patients were glycated hemoglobin, hypertension, age, duration of diabetes, body mass index and estimated glomerular filtration rate. In contrast, factors to related renal dysfunction were age, duration of diabetes, dyslipidemia, hypertension, body mass index, male sex and albuminuria.

CONCLUSIONS

We showed the recent prevalence of albuminuria and renal dysfunction, and related factors in Japanese type 1 and type 2 diabetes patients using the baseline data of the Japan Diabetes Complication and its Prevention prospective study. The current results suggest that renal disease in patients with type 2 diabetes is heterogeneous, and different mechanisms might be involved in albuminuria and deterioration of renal function.

Exposure to maternal obesity programs sex differences in pancreatic islets of the offspring in mice

AIMS/HYPOTHESIS

Obesity during pregnancy increases offspring type 2 diabetes risk. Given that nearly half of women of child-bearing age in many populations are currently overweight/obese, it is key that we improve our understanding of the impact of the in utero/early life environment on offspring islet function. Whilst a number of experimental studies have examined the effect of maternal obesity on offspring islet architecture and/or function, it has not previously been delineated whether these changes are independent of other confounding risk factors such as obesity, postnatal high-fat-feeding and ageing. Thus, we aimed to study the impact of exposure to maternal obesity on offspring islets in young, glucose-tolerant male and female offspring.

METHODS

Female C57BL/6J mice were fed ad libitum either chow or obesogenic diet prior to and throughout pregnancy and lactation. Offspring were weaned onto a chow diet and remained on this diet until the end of the study. An IPGTT was performed on male and female offspring at 7 weeks of age. At 8 weeks of age, pancreatic islets were isolated from offspring for measurement of insulin secretion and content, mitochondrial respiration, ATP content, reactive oxygen species levels, beta and alpha cell mass, granule and mitochondrial density (by transmission electron microscopy), and mRNA and protein expression by real-time RT-PCR and Western blotting, respectively.

RESULTS

Glucose tolerance was similar irrespective of maternal diet and offspring sex. However, blood glucose was lower (p < 0.001) and plasma insulin higher (p < 0.05) in female offspring of obese dams 15 min after glucose administration. This was associated with higher glucose- (p < 0.01) and leucine/glutamine-stimulated (p < 0.05) insulin secretion in these offspring. Furthermore, there was increased mitochondrial respiration (p < 0.01) and density (p < 0.05) in female offspring of obese dams compared with same-sex controls. Expression of mitochondrial and nuclear-encoded components of the electron transport chain, L-type Ca²⁺ channel subtypes that play a key role in stimulus-secretion coupling [Cacna1d (p < 0.05)], and oestrogen receptor α (p < 0.05) was also increased in islets from these female offspring of obese dams. Moreover, cleaved caspase-3 expression and BAX:Bcl-2 were decreased (p < 0.05) reflecting reduced susceptibility to apoptosis. In contrast, in male offspring, glucose and leucine/glutamine-stimulated insulin secretion was comparable between treatment groups. There was, however, compromised mitochondrial respiration characterised by decreased ATP synthesis-driven respiration (p < 0.05) and increased uncoupled respiration (p < 0.01), reduced docked insulin granules (p < 0.001), decreased Cacna1c (p < 0.001) and Cacna1d (p < 0.001) and increased cleaved caspase-3 expression (p < 0.05).

CONCLUSIONS/INTERPRETATION

Maternal obesity programs sex differences in offspring islet function. Islets of female but not male offspring appear to be primed to cope with a nutritionally-rich postnatal environment, which may reflect differences in future type 2 diabetes risk.

Response to "Preserved" glucagon secretion in fulminant type 1 diabetes

We compared the glucagon responses to arginine stimulation in five patients with fulminant type 1 diabetes and five age- and diabetes duration-matched acute-onset type 1 diabetes, and the curves of the glucagon responses were similar. In our study, we measured the glucagon levels by not only radioimmunoassay, but also novel enzyme-linked immunosorbent assay.

Clinical and Genetic Characteristics of Non-Insulin-Requiring Glutamic Acid Decarboxylase (GAD) Autoantibody-Positive Diabetes: A Nationwide Survey in Japan

Aims

Glutamic acid decarboxylase autoantibodies (GADAb) differentiate slowly progressive insulin-dependent (type 1) diabetes mellitus (SPIDDM) from phenotypic type 2 diabetes, but many GADAb-positive patients with diabetes do not progress to insulin-requiring diabetes. To characterize GADAb-positive patients with adult-onset diabetes who do not require insulin therapy for >5 years (NIR-SPIDDM), we conducted a nationwide cross-sectional survey in Japan.

Methods

We collected 82 GADAb-positive patients who did not require insulin therapy for >5 years (NIR-SPIDDM) and compared them with 63 patients with insulin-requiring SPIDDM (IR-SPIDDM). Clinical and biochemical characteristics, HLA-DRB1-DQB1 haplotypes, and predictive markers for progression to insulin therapy were investigated.

Results

Compared with the IR-SPIDDM group, the NIR-SPIDDM patients showed later diabetes onset, higher body mass index, longer duration before diagnosis, and less frequent hyperglycemic symptoms at onset. In addition, C-peptide, LDL-cholesterol, and TG were significantly higher in the NIR-SPIDDM compared to IR-SPIDDM patients. The NIR-SPIDDM group had lower frequency of susceptible HLA-DRB1*04:05-DQB1*04:01 and a higher frequency of resistant HLA-DRB1*15:01-DQB1*06:02 haplotype compared to IR-SPIDDM. A multivariable analysis showed that age at diabetes onset (OR = 0.82), duration before diagnosis of GADAb-positive diabetes (OR = 0.82), higher GADAb level (≥10.0 U/ml) (OR = 20.41), and fasting C-peptide at diagnosis (OR = 0.07) were independent predictive markers for progression to insulin-requiring diabetes. An ROC curve analysis showed that the optimal cut-off points for discriminating two groups was the GADAb level of 13.6 U/ml, age of diabetes onset of 47 years, duration before diagnosis of 5 years, and fasting C-peptide of 0.65 ng/ml.

Conclusions

Clinical, biochemical and genetic characteristics of patients with NIR-SPIDDM are different from those of IR-SPIDDM patients. Age of diabetes onset, duration before GADAb-positivity, GADAb level, and fasting C-peptide at diagnosis must be carefully considered in planning prevention trials for SPIDDM.