HbA1c and biomarkers of diabetes mellitus in Clinical Chemistry and Laboratory Medicine: ten years after

Since its discovery in the late 1960s, HbA_1c has proven to be a major biomarker of diabetes mellitus survey and diagnosis. Other biomarkers have also been described using classical laboratory methods or more innovative, non-invasive ones. All biomarkers of diabetes, including the historical glucose assay, have well-controlled strengths and limitations, determining their indications in clinical use. They all request high quality preanalytical and analytical methodologies, necessitating a strict evaluation of their performances by external quality control assessment trials. Specific requirements are needed for point-of-care testing technologies. This general overview, which describes how old and new tools of diabetes mellitus biological survey have evolved over the last decade, has been built through the prism of papers published in Clinical Chemistry and Laboratory Medicine during this period.

Cross-reactive peptide epitopes of Enterovirus Coxsackie B4 and human glutamic acid decarboxylase detecting antibodies in latent autoimmune diabetes in adults versus type 1 diabetes

BACKGROUND

Diagnosis of latent autoimmune diabetes in adults (LADA) is usually based on the adult age, anti-pancreatic islet cell antibodies detection, and insulin independence. This study investigates the diagnostic value of antibodies against human glutamic acid decarboxylase (hGAD) peptides in LADA and type 1 diabetes mellitus (T1DM) patients, and their cross-reactivity with an Enterovirus Coxsackie B4 (CVB4) shared epitope.

METHODS

Sera from 27 LADA patients, 23 T1DM patients, and 24 controls were tested in ELISA for antibodies against hGAD peptides and a selected sequence of P2C protein of CVB4 (CVB4P2C). Diagnostic power of peptides was analyzed by ROC-curve analysis and cross-reactivity among peptides evaluated.

RESULTS

IgM and IgG antibodies showed significant differences between LADA and T1DM versus controls for all peptides. Antibody responses present high agreement among peptides for IgM and IgG-isotypes in T1DM, which is not reproduced in LADA. IgM antibodies showed high predicting diagnostic power particularly in LADA (sensitivity > 85%, specificity 95.8%).

CONCLUSIONS

Our study highlights the usefulness of peptides as diagnostic antigens in T1DM and LADA, and extends previous findings by comparing IgM and IgG-isotype antibodies in the same population. Additionally, results highlight the role of the entourage in the shared sequon PEVKXK in GAD and CVB4P2C particularly in IgMs identification.

Factors associated with glycaemic control in patients with diabetes mellitus: A systematic literature review

OBJECTIVES

To perform a systematic review search and critically review the empirical evidence concerning the factors affecting glycaemic control in patients with type 1 or 2 diabetes mellitus.

BACKGROUND

Previous primary studies have investigated the factors associated with glycaemic control among patients with type 1 or 2 diabetes, but attempts to amalgamate these evidences have been methodologically limited. Hence, a robust review of the evidence is essential to explore factors that can be addressed to promote good glycaemic control in patients with diabetes.

DESIGN

Mixed-method systematic review using the Preferred Reporting Items for Systematic review and Meta-Analysis 2009 flow diagram, integrating evidence from qualitative and quantitative studies (see Supporting Information File S1).

METHODS

A systematic review of the literature published between 2006-2017 was conducted in seven electronic databases (CINAHL, MEDLINE, Scopus, EMBASE, PsycINFO, PubMed and ScienceDirect) using the search terms "diabetes mellitus," "glycemic control," "self-concept," "knowledge," "self-efficacy," "empowerment," "race," "ethnicity," "duration," "medication," "obesity" and "comorbidity."

RESULTS

A total of 1,582 articles were initially retrieved, and 24 of these articles were included in this systematic literature review. The overall empirical evidence suggested that higher socio-economic status, greater dietary knowledge, and higher self-efficacy and empowerment improve glycaemic control among patients with diabetes mellitus.

CONCLUSIONS

This review presented the factors associated with glycaemic control that may pose significant socio-economic problems to most nations worldwide and impede development nationally, regionally and even globally. Greater emphasis needs to be placed on implementing lifestyle changes on a societal level to stem the tide of the epidemic.

RELEVANCE TO CLINICAL PRACTICE

There is a need to implement self-management initiatives, that incorporate dietary knowledge, to empower patients with diabetes in their own care. Future public health policy must be geared towards increasing the capability of dealing with the rising incidence of diabetes and implementing primary prevention.

Antibodies to post-translationally modified mitochondrial peptide PDC-E2(167-184) in type 1 diabetes

BACKGROUND

Mitochondria play a role in type 1 diabetes (T1D) particularly in the treatment and prevention of disorder consequences. Due to their demonstrated role in diabetes pathology, mitochondrial proteins can be an interesting starting point to study candidate antigens in T1D. We investigated the role of relevant post-translational modifications (PTM) on a synthetic mitochondrial peptide as putative antigen.

METHODS

The antibody response in T1D was evaluated by solid phase-ELISA using a collection of synthetic peptides bearing different PTMs. We investigated the role of lipoylation, phosphorylation, and glycosylation. The PTMs were introduced at position 173 of the mitochondrial pyruvate dehydrogenase E2 complex peptide PDC-E2(167-184) and at position 7 of a structure-based designed β-turn peptide as an irrelevant sequence to investigate the role of the specific PDC-E2 peptide sequence.

RESULTS

IgM titres in 31 T1D patients were higher than IgGs to all the synthetic PTM peptides. Results demonstrated the crucial role of lysine lipoamide, serine O-phosphorylation, and O-glycosylation into the PDC-E2(167-184) peptide sequence for IgM antibody recognition.

CONCLUSIONS

Results highlight the importance of immune dysregulation in T1D, furthermore, if confirmed in a large number of patients, they will contribute to add novel diagnostic markers for the understanding the physiopathology of the disease.

Long-term outcomes of patients with type 2 diabetes attending a multidisciplinary diabetes kidney disease clinic

BACKGROUND

The best model of care to retard diabetic kidney disease (DKD) in the clinic is underexplored. In this study we investigated the long-term renal outcomes of a joint endocrinologist-nephrologist clinic.

METHODS

The present study was a nested case-control study derived from a cohort of patients with type 2 diabetes mellitus (T2DM) seen prospectively at a secondary care diabetes center (DC). Cases ("DKD clinic group") were patients seen at the CKD clinic after being referred by physicians in DCs for management of DKD. Controls ("non-DKD clinic group") were patients from the same DC (i.e. same source population) with the same inclusion criteria of Stages 3-4 chronic kidney disease (CKD) at baseline but not seen at the DKD clinic. The outcome was Stage 5 CKD, defined as an estimated glomerular filtration rate <15 mL/min per 1.73 m² .

RESULTS

During the median follow-up period of 3.0 years (interquartile range 1.2-5.1 years), 240 patients (28.7%) reached Stage 5 CKD, with 45.8% and 54.2% of those reaching Stage 5 CKD in the DKD and non-DKD clinic groups, respectively. Multivariable Cox regression revealed that the DKD clinic group had a lower risk of progressing to Stage 5 CKD (hazard ratio 0.55; 95% confidence interval 0.36-0.83; P = 0.004) compared with the non-DKD clinic group.

CONCLUSIONS

Multidisciplinary endocrinology and nephrology care in the DKD clinic is associated with a lower risk of end-stage renal disease. These findings may inform future management strategies targeted at patients with T2DM and CKD, especially with regard to joint specialist management involving endocrinologists and nephrologists.

Discovery and validation of serum creatinine variability as novel biomarker for predicting onset of albuminuria in Type 2 diabetes mellitus

AIM

We aim to study association serum creatinine(cr) variability and albuminuria progression.

METHODS

We conducted a retrospective cohort study on patients with Type 2 Diabetes Mellitus at a Diabetes Centre in Singapore ("discovery cohort"). Outcome is worsening of urinary albumin-to-creatinine(ACR) across stages. Cr variability was expressed as adjusted cr-intrapersonal standard deviation(SD) and coefficient-of-variation(cr-CV). A separate cohort was used for validating association between cr variability and albuminuria progression ("validation cohort").

RESULTS

Over median follow-up of 4.2 years, 38.4% of 636 patients had albuminuria progression in the discovery cohort. Increasing log-transformed adjusted cr-intrapersonal SD and cr-CV were significantly associated with albuminuria progression: HRs 1.43 (95%CI 1.11-1.85) and 1.44 (1.11-1.87) respectively in the discovery cohort, and HRs 1.94 (1.09-3.45) and 1.91 (1.05-3.45) respectively in the validation cohort. When stratified by baseline urinary ACR, higher cr variability was significantly associated with albuminuria progression in patients with normoalbuminuria but not microalbuminuria.

CONCLUSIONS

Cr variability independently predicts albuminuria onset. This is evident in patients with normoalbuminuria, suggesting that higher cr variability could herald albuminuria onset.

Effect of long-term glycemic variability on estimated glomerular filtration rate decline among patients with type 2 diabetes mellitus: Insights from the Diabetic Nephropathy Cohort in Singapore

BACKGROUND

In the present study, we examined the association between HbA1c variability and renal disease progression based on estimated glomerular filtration rate (eGFR) decline in patients with type 2 diabetes mellitus (T2DM) in Singapore.

METHODS

Glycemic burden and renal function were retrospectively assessed in 1628 patients in 2002-2014. Multivariable logistic regression was used to assess the relationships between HbA1c variability (expressed as HbA1c coefficient of variation [HbA1c-CV] in quartiles), HbA1c intrapersonal mean (HbA1c-IM), and eGFR decline, adjusted for baseline covariates.

RESULTS

Among patients with relatively good glycemic control (i.e. HbA1c-IM below the median cohort value [8.0%]), HbA1c-CV Quartile 4 was associated with eGFR decline (odds ratio [OR] 1.88; 95% confidence interval [CI] 1.10-3.25). The OR for HbA1c-CV Quartile 4 was 2.20 (95% CI 1.24-3.89) after additional adjustment for HbA1c-IM. Where HbA1c-IM was above the median cohort value, HbA1c-CV Quartiles 3 and 4 were associated with eGFR decline, with ORs of 2.60 (95% CI 1.48-4.55) and 3.29 (95% CI 1.89-5.76) respectively. After further adjusting for HbA1c-IM, the ORs for Quartiles 3 and 4 were 2.69 (95% CI 1.53-4.74) and 3.51 (95% CI 1.98-6.21), respectively.

CONCLUSIONS

Variability in HbA1c is strongly and independently associated with eGFR decline in patients with T2DM independent of mean HbA1c. The findings may highlight the importance of sustained stable glycemic control in management of diabetes mellitus.

Plasma phospholipid fatty acid composition and desaturase activity in women with gestational diabetes mellitus before and after delivery

AIMS

Analyze plasma phospholipid fatty acids (PPFA) composition and desaturase activity in women with gestational diabetes (GDM) and in women with a normal glucose tolerance (NGT) before and after delivery, and to evaluate the possible relationship between desaturase activity and inflammatory parameters.

METHODS

PPFA composition was analyzed by gas chromatography in 21 women with GDM and from 21 with NGT, during the third trimester of pregnancy and 6 months after delivery. We used fatty acid product-to-precursor ratios to estimate desaturase activity, and we also measured in all women interleukins six and ten, tumor necrosis factor alpha and C-reactive protein.

RESULTS

No significant differences were observed between NGT and GDM women in terms of PPFA composition, both in pregnancy and after pregnancy. Estimated desaturase Δ9-18 activity was significantly higher, and estimated desaturase Δ5 activity was significantly lower during pregnancy in all women. We observed no correlations between inflammatory markers and desaturases activity, during or after pregnancy, in both groups.

CONCLUSIONS

Our data suggest that GDM does not influence PPFA composition and desaturase activity during pregnancy. In addition, late pregnancy characterized by hyperinsulinemia appears to upregulate desaturase Δ9-18 activity in NGT and GDM women.

Onset and progression of kidney disease in type 2 diabetes among multi-ethnic Asian population

AIM

To elucidate the natural history of chronic kidney disease(CKD), which is defined as estimated glomerular filtration rate(eGFR)<60ml/min/1.73m(2) and/or increase of urinary albumin-to-creatinine ratio (uACR)≥30mg/g), and to identify factors associated with its onset and progression.

METHODS

Prospective cohort study on individuals with T2DM attending Diabetes Centre in a regional hospital in Singapore from 2002. There were 553 patients with no pre-existing CKD for "onset" analysis and 967 patients with pre-existing CKD for "progression" analysis. Multivariable logistic regression was performed to determine risk factors of the outcomes.

RESULTS

The mean follow-up period was 5.8years (4.5-7.1) and 5.3years (3.9-6.9) for the onset and progression cohorts respectively. About 45% of individuals developed CKD and 41% had progression. Among subjects with CKD onset, albuminuria-only occurred in 75% of them. Majority of the patients remained in the same CKD risk-category during follow-up. Progression and regression occurred across all CKD-categories. Transitions to adjacent risk-category were much more likely than transitions bypassing adjacent state. Risk factors for CKD onset included baseline albuminuria, eGFR, HbA1c variability, body mass index, triglycerides and age (all P<0.05). The predictors for CKD progression or rapid-progression included HbA1c variability, baseline albuminuria, systolic blood pressure, LDL-cholesterol, eGFR, HbA1c and ethnicity (all P<0.05).

CONCLUSIONS

Albuminuria was the first manifestation of CKD in most T2DM patients. Transition across CKD-category occurred bi-directionally, but evolved largely in a stepwise fashion. The onset and progression of CKD were predicted by multiple risk factors, some of which were modifiable.

Benchmarking by HbA1c in a national diabetes quality register--does measurement bias matter?

BACKGROUND

Bias in HbA1c measurement could give a wrong impression of the standard of care when benchmarking diabetes care. The aim of this study was to evaluate how measurement bias in HbA1c results may influence the benchmarking process performed by a national diabetes register.

METHODS

Using data from 2012 from the Norwegian Diabetes Register for Adults, we included HbA1c results from 3584 patients with type 1 diabetes attending 13 hospital clinics, and 1366 patients with type 2 diabetes attending 18 GP offices. Correction factors for HbA1c were obtained by comparing the results of the hospital laboratories'/GP offices' external quality assurance scheme with the target value from a reference method.

RESULTS

Compared with the uncorrected yearly median HbA1c values for hospital clinics and GP offices, EQA corrected HbA1c values were within ±0.2% (2 mmol/mol) for all but one hospital clinic whose value was reduced by 0.4% (4 mmol/mol). Three hospital clinics reduced the proportion of patients with poor glycemic control, one by 9% and two by 4%.

CONCLUSIONS

For most participants in our study, correcting for measurement bias had little effect on the yearly median HbA1c value or the percentage of patients achieving glycemic goals. However, at three hospital clinics correcting for measurement bias had an important effect on HbA1c benchmarking results especially with regard to percentages of patients achieving glycemic targets. The analytical quality of HbA1c should be taken into account when comparing benchmarking results.

Evaluation of empowerment model on indicators of metabolic control in patients with type 2 diabetes, a randomized clinical trial study

AIMS

Diabetes education is a major subject in achieving optimal glycemic control. Effective empowerment approach can be beneficial for improving patients' health. The aim of this study was to evaluate the effect of empowerment model on indicators of metabolic control in patients with type 2 diabetes.

METHODS

a randomized controlled trial of 103 patients with type 2 diabetes were randomly assigned to either the intervention (empowerment approach training) or the control group (conventional training) 2014. Empowerment approach training were performed for the experimental group for eight weeks. Data collection tool included demographic information form and indicators of metabolic control checklist. Analysis was performed by one-way analysis of variance, chi-square test, paired t-test, independent t-test and multiple linear regression.

RESULTS

Before the intervention, two groups were homogeneous in terms of demographic variables, glycosylated hemoglobin (HbA1C), and other indicators of metabolic control. After the intervention, average HbA1C and other metabolic indicators except for LDL showed significant differences in the experimental group compared to the control group.

CONCLUSION

study results indicated the positive effects of applying the empowerment model on the metabolic control indicators. Therefore, applying this model is recommended to nurses and the relevant authorities in order to improve clinical outcomes in diabetic patients.

Measurement of glycated albumin in serum and plasma by LC-MS/MS

BACKGROUND

Diagnosis of diabetes and monitoring of long-term blood sugar are preferably done by measurement of glycated hemoglobin (HbA1c). Diabetic patients with end stage renal disease (ESRD) may have short-lived red blood cells due to hemodialysis (HD), and thus higher turnover of hemoglobin. The level of glycated hemoglobin (HbA1c) may be lower than expected for these patients, even at increased blood glucose, possibly making glycated albumin (GA) measurement a better alternative.

METHODS

The percentage of GA was measured by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Fast and efficient trypsin digestion of proteins in diluted serum or plasma resulted in a high number of proteotypic peptides from albumin, including KQTALVELVK which was detected both glycated and non-glycated by multiple reaction monitoring (MRM). The percentage of GA was estimated by neat peak area response of glycated peptide divided by the sum of glycated and non-glycated peptide.

RESULTS

Acceptable method reproducibility (6% CV), repeatability (2-6% CV), limit of quantification (0.75% GA), linearity (R(2) = 0.999) and recovery (79 ± 9%) was achieved without using calibration or isotope-labeled internal standard. GA was strongly correlated with HbA1c (r = 0.84) for patients without ESRD. The average ratio of GA/HbA1c was significantly higher (p = 0.0021) for ESRD patients (1.84 ± 0.38, n = 62) compared to other patients (1.67 ± 0.28, n = 225).

CONCLUSION

GA measurement by detecting glycation in KQTALVELVK with LC-MS/MS seems to be a useful supplement to HbA1c for detecting increased blood glucose in diabetic patients with ESRD.

Standardising HbA1c-based diabetes diagnosis: opportunities and challenges

Globally, the incidence of diabetes mellitus is rising at an alarming rate and has become a health crisis that threatens the economies of all nations. Therefore, diagnosing diabetes has become an important issue in the management of diabetes. Glycated hemoglobin (HbA1c) is now recommended as a means to diagnose diabetes, but its use still has limitations. In this article, the biology, measurement, standardization, and opportunities and challenges of the use of HbA1c to diagnose diabetes are reviewed. More specifically, its use in China and the Asian region is discussed in detail.

Diabetic pregnancy outcomes in mothers treated with basal insulin lispro protamine suspension or NPH insulin: a multicenter retrospective Italian study

OBJECTIVE

The aim of this study was to study the efficacy and safety of long-acting insulin analog insulin lispro protamine suspension (ILPS) in diabetic pregnant women.

METHODS

In a multicenter observational retrospective study, we evaluated pregnancy outcome in 119 women affected by type 1 diabetes and 814 with gestational diabetes (GDM) treated during pregnancy with ILPS, compared with a control group treated with neutral protamine hagedorn (NPH) insulin.

RESULTS

Among type 1 diabetic patients, fasting blood glucose at the end of pregnancy was significantly lower in ILPS-treated than in NPH-treated patients. HbA1c levels across pregnancy did not differ between groups. Caesarean section and preterm delivery rates were significantly lower in the ILPS-women. Fetal outcomes were similar in the ILPS and NPH groups. Among GDM women, fasting blood glucose at the end of pregnancy was significantly lower in ILPS-treated than in NPH-treated patients. Duration of gestation was significantly longer, caesarian section and preterm delivery rates were lower in the ILPS-treated group. In addition, there were significantly fewer babies with an excessive ponderal index or neonatal hypoglycemic episodes in the ILPS group than in the NPH group.

CONCLUSIONS

Association of ILPS with rapid-acting analogs in pregnancy is safe in terms of maternal and fetal outcomes.

Screening with HbA1c identifies only one in two individuals with diagnosis of prediabetes at oral glucose tolerance test: findings in a real-world Caucasian population

OBJECTIVE

Discordance between HbA1c and OGTT in screening pre-diabetes may occur because of lack of laboratory standardization, distinct underlying pathophysiological processes or different ethnicity. We evaluated HbA1c efficacy for screening OGTT-defined IFG and IGT conditions in a large Caucasian population using the newly revised IFCC protocol.

RESEARCH DESIGN AND METHODS

A total of 501 consecutive subjects were screened for pre-diabetic conditions with OGTT with 75 g of glucose. Testing for HbA1c, lipid profile and fasting insulin levels was also performed. For detecting differences between continuous variables, ANOVA followed by Tukey's honestly significant difference (HSD) post hoc test was used. Logistic regression and ROC curve analysis were also performed for assessing HbA1c screening efficacy.

RESULTS

ROC curve analysis showed that optimal HbA1c cut-off for detecting IFG was 5.6 % (sensitivity of 78 % and specificity of 63 %), while for IGT, the optimal cut-off was 5.9 % (sensitivity of 46 % and specificity of 84 %), with AUCs < 0.8. Screening with HbA1c identified 53.4 % of the 193 patients with IFG and/or IGT diagnosed at OGTT. As regards surrogate markers of insulin resistance, we observed a trend towards higher values of HOMA-IR and lower QUICKI values in subjects with IFG than in those with IGT. Patients with pre-diabetes at both tests had similar values of HOMA and QUICKI, compared with those with altered OGTT only.

CONCLUSIONS

IFCC-aligned HbA1c assay proved scarcely effective in detecting IFG and/or IGT in a large Caucasian population, identifying only half of the patients with abnormal OGTT. Moreover, adding HbA1c screening to OGTT may be of little benefit in identifying subjects with a worse metabolic profile.

Post-translational modification derived products (PTMDPs): toxins in chronic diseases?

In living organisms, proteins are progressively modified by spontaneous non-enzymatic reactions generating many post-translational modification derived products (PTMDPs) which exert deleterious effects and may be considered endogenous toxins in diabetes mellitus and chronic renal failure. Non-enzymatic glycation, which refers to the spontaneous binding of reducing sugars to free amino groups, is increased in diabetes mellitus because of hyperglycemia and is amplified by oxidative processes ('glycoxidation'). Glycoxidation leads to the formation of 'advanced glycation end products' (AGEs), together with products of other oxidative pathways. AGEs alter tissue organization and cell-protein interactions, mainly in the case of long-lived extracellular matrix proteins, and interact with membrane receptors, among which RAGE (receptor of AGEs), a multiligand receptor which triggers intracellular signaling pathways stimulating inflammatory functions. Another major protein modification, carbamylation, is increased in chronic renal failure, which may occur during the course of diabetes mellitus. Carbamylation is due to the binding of isocyanic acid on the α-NH2 extremity of proteins or amino acids, or on ε-NH2 lysine groups, generating homocitrulline, a potential biomarker in atherosclerosis. Isocyanic acid is formed in vivo either by spontaneous dissociation of urea or by myeloperoxidase action on thiocyanate. Carbamylated proteins exhibit altered properties. For example, carbamylated collagen is unable to stimulate oxidative functions of polymorphonuclear neutrophils but increases matrix metalloproteinase-9 production by monocytes. Lipoprotein functions are altered by carbamylation and may contribute to atherogenesis. Thus, the numerous PTMDPs may be considered both hallmarks of protein damage in chronic diseases and endogenous toxins acting at the molecular and cellular levels.

[Assays of HbA1c and Amadori products in human biology]

Different Amadori products, formed during the early steps of the non-enzymatic glycation of proteins, may be assayed in current practice in human biology. The most important marker is HbA1c, resulting from the binding of glucose to the N-terminal extremity of HbA beta chains. HbA1c may be evaluated by various techniques (ion exchange or affinity high performance liquid chromatography, capillary electrophoresis, immunoassay, enzymatic technique) and is considered the best marker of diabetic patient survey. Due to its irreversible and cumulative formation, it provides a retrospective information on the glycemic balance over the four to eight weeks preceding blood collection. It benefits from an international standardization, based on a reference method using liquid chromatography coupled to capillary electrophoresis or mass spectrometry, maintained by an international network of reference laboratories. When HbA1c assay cannot be used (anemia, hemolysis, hemoglobinopathy) or when a shorter period of glycemic equilibrium must be evaluated (child and adolescent, pregnancy, therapeutic changes), other Amadori products may be assayed, like plasma fructosamine (all plasma glycated proteins) or glycated albumin. Nevertheless, these assays are less used in practice, because their semiological value has been less evidenced. Besides, fructosamine assay lacks specificity, and glycated albumin assay has been described recently. An expanding use of HbA1c assay is expected, especially for the diagnosis of diabetes mellitus and the evaluation of other risks, especially cardiovascular ones.

Diabetic Worker with History of Falls: A Case Study

A 58-year old male employee presented to the occupational health clinic for evaluation after experiencing several falls. He had been diagnosed as having type II diabetes 5 years earlier. The physical examination noted peripheral neuropathy. This article reviews the effects of diabetes on peripheral nerves and discusses interventions that the occupational health nurse may use to monitor workers with diabetes.

Economic evaluation of continuous subcutaneous insulin infusion for children with diabetes - a pilot study: CSII application for children - economic evaluation

Background

The objective of this study is to assess the cost of using continuous subcutaneous insulin infusion to treat children with type-1diabetes in Bulgaria, considering changes in body mass index (BMI) and the glycated hemoglobin. The study was performed from the perspective of the Bulgarian National Health Insurance Fund (NHIF) and patients.

Methods

A total of 34 pediatric type-1-diabetes patients were observed for 7 months, divided into 2 groups – on pumps and on insulin analogue therapy. Patient demographic data, BMI and glycated hemoglobin level were obtained and recorded. The cost of insulin, pumps, and consumables were calculated and compared with changes in glycated hemoglobin level. The incremental cost-effectiveness ratio was below the threshold value of gross domestic product per capita.

Results

The results were sensitive to changes in glycated hemoglobin level. Improvements associated with glycemic control led to a reduced glycated hemoglobin level that could ensure good diabetes management, but its influence on BMI in growing children remains unclear.

Conclusion

Continuous subcutaneous insulin infusion appears to be more cost-effective for the Bulgarian pediatric population and health care system.