Identification of a Common Variant for Coronary Heart Disease at PDE1A Contributes to Individualized Treatment Goals and Risk Stratification of Cardiovascular Complications in Chinese Patients With Type 2 Diabetes

OBJECTIVE

In this study we aim to unravel genetic determinants of coronary heart disease (CHD) in type 2 diabetes (T2D) and explore their applications.

RESEARCH DESIGN AND METHODS

We performed a two-stage genome-wide association study for CHD in Chinese patients with T2D (3,596 case and 8,898 control subjects), followed by replications in European patients with T2D (764 case and 4,276 control subjects) and general populations (n = 51,442-547,261). Each identified variant was examined for its association with a wide range of phenotypes and its interactions with glycemic, blood pressure (BP), and lipid controls in incident cardiovascular diseases.

RESULTS

We identified a novel variant (rs10171703) for CHD (odds ratio 1.21 [95% CI 1.13-1.30]; P = 2.4 × 10-8) and BP (β ± SE 0.130 ± 0.017; P = 4.1 × 10-14) at PDE1A in Chinese T2D patients but found only a modest association with CHD in general populations. This variant modulated the effects of BP goal attainment (130/80 mmHg) on CHD (Pinteraction = 0.0155) and myocardial infarction (MI) (Pinteraction = 5.1 × 10-4). Patients with CC genotype of rs10171703 had >40% reduction in either cardiovascular events in response to BP control (2.9 × 10-8 < P < 3.6 × 10-5), those with CT genotype had no difference (0.0726 < P < 0.2614), and those with TT genotype had a threefold increase in MI risk (P = 6.7 × 10-3).

CONCLUSIONS

We discovered a novel CHD- and BP-related variant at PDE1A that interacted with BP goal attainment with divergent effects on CHD risk in Chinese patients with T2D. Incorporating this information may facilitate individualized treatment strategies for precision care in diabetes, only when our findings are validated.

Optimizing Glycemic Control Through Titration of Insulin Glargine 100 U/mL: A Review of Current and Future Approaches with a Focus on Asian Populations

Various data have demonstrated inadequate glycemic control amongst Asians with type 2 diabetes mellitus (T2DM), possibly on account of suboptimal titration of basal insulin-an issue which needs to be further examined. Here we review the available global and Asia-specific data on titration of basal insulin, with a focus on the use of insulin glargine 100 U/mL (Gla-100). We also discuss clinical evidence on the efficacy and safety of titrating Gla-100, different approaches to titration, including some of the latest technological advancements, and guidance on the titration of basal insulin from international and local Asian guidelines. The authors also provide their recommendations for the initiation and titration of basal insulin for Asian populations. Discussion of the data included in this review and in relation to the authors' clinical experience with treating T2DM in Asian patients is also included. Briefly, clinical studies demonstrate the achievement of adequate glycemic control in adults with T2DM through titration of Gla-100. However, studies investigating approaches to titration, specifically in Asian populations, are lacking and need to be conducted. Given that the management of insulin therapy is a multidisciplinary team effort involving endocrinologists, primary care physicians, nurse educators, and patients, greater resources and education targeted at these groups are needed regarding the optimal titration of basal insulin. Technological advancements in the form of mobile or web-based applications for automated dose adjustment can aid different stakeholders in optimizing the dose of basal insulin, enabling a larger number of patients in Asia to reach their target glycemic goals with improved outcomes.

Practical considerations for the use of sodium-glucose co-transporter type 2 inhibitors in treating hyperglycemia in type 2 diabetes

Sodium-glucose co-transporter type 2 (SGLT2) inhibitors are a new class of oral anti-diabetic agents with a unique, insulin-independent mode of action. In patients with diabetes who have adequate renal function, SGLT2 inhibitors reduce hyperglycemia by blocking renal glucose reabsorption and increasing urinary glucose excretion. These agents are indicated for the treatment of hyperglycemia in type 2 diabetes mellitus (T2DM), as an adjunct to diet and exercise. In terms of efficacy, they are comparable to most other oral agents, and carry a low risk of hypoglycemia unless combined with sulfonylureas or insulin. They may be used in combination regimens with metformin, sulfonylureas, or insulin. Beyond glucose lowering, SGLT2 inhibitors are associated with modest weight loss and mild anti-hypertensive effects. Emerging cardiovascular and renal outcomes data suggest other potentially beneficial non-glycemic effects, although these findings await confirmation from further studies. The main adverse effects are increased risk of volume depletion and of genitourinary infections, although these can be managed with standard interventions. Rare cases of euglycemic ketoacidosis have been reported in a subset of patients treated with these agents, an issue currently under investigation. SGLT2 inhibitors represent a promising alternative treatment option for T2DM patients in whom the effectiveness of oral anti-hyperglycemic therapy is limited by the risk of hypoglycemia, weight gain, or other adverse effects. Safety and efficacy (up to 4 years) have been demonstrated in a range of T2DM patient populations, although more studies will be needed to determine whether treatment with SGLT2 inhibitors improves patient-important outcomes in the longer term.

Cost of Type 2 Diabetes mellitus in Hong Kong Chinese

OBJECTIVE

Hong Kong (HK) is a special administrative region of China as well as being a metropolitan city. In HK, like in many developed countries, Diabetes mellitus, with over 97% of diabetic patients having Type 2 Diabetes mellitus (Type 2 DM), is a growing public health problem but the local financial burden has never been investigated. The primary objectives of this study were to evaluate from the social perspective the costs of Type 2 DM, to identify the major cost drivers, and the proportion of the burden shared by the government, patient and the society. The study was carried out in a group of Hong Kong Chinese patients attending a government hospital. The economic impact of Type 2 DM on local and governmental healthcare expenditure was also examined.

METHODS

A retrospective cohort observational study was conducted in Type 2 DM patients attending the Diabetes Mellitus Outpatient Clinic at a public hospital in the period January 2004 to May 2004, in which 204 patients were randomly selected and invited to join this study. A total of 147 patients were subsequently enrolled giving an inclusion rate of 72%.

RESULTS

Annual total cost of Type 2 DM in a patient was US$ 1,725 +/- 2,044 (HK$ 13,457 +/- 15,943) with direct costs accounting for > 87.9%. The government was the major payer with over 78.4% of the total costs. Annual total direct medical costs per patient were US$ 1,492 +/- 1,716 (HK$ 11,638 +/- 13,386) of which the government paid 90.6%. Direct medical costs increased markedly if complications were present. In patients with microvascular or macrovascular complications only, the costs increased 1.1-fold compared to those for patients without complications. If both microvascular and macrovascular complications were present in the same patient, the costs were 1.3-fold higher than in patients without complications.

CONCLUSION

Costs of Type 2 DM have a significant impact on the local healthcare budget. It contributed in 2004 up to 3.9% of the total HK healthcare expenditure and 6.4% of the HK Hospital Authority's (public sector) expenditures on health.

Nurse follow-up of patients with diabetes: randomized controlled trial

AIM

This paper reports a study comparing the outcomes of diabetic patients undergoing either early discharge or routine care.

BACKGROUND

The hospital is not the best place to monitor the glycaemic control of patients with diabetes with no other morbidity or complications. It is an unnatural environment in which diet is planned and the activity level is low. The hospital is also an expensive place in which to treat patients.

METHODS

This randomized controlled trial was conducted in the medical department of a regional hospital in Hong Kong. A total of 101 patients who needed glycaemic monitoring, but who were otherwise fit for discharge, were recruited. The control group continued to receive routine hospital care. The study group was discharged early and received a follow-up programme which included a weekly or biweekly telephone call from a nurse.

FINDINGS

When compared with the control group, the study group had a greater decrease in HbA1c at 24 weeks, although the statistical difference was marginal (7.6 vs. 8.1, P = 0.06), a higher blood monitoring adherence score at both 12 weeks (5.4 vs. 3.6, P < 0.001) and 24 weeks (5.3 vs. 3.5, P < 0.001), and a higher exercise adherence score at 12 weeks (5.3 vs. 3.4, P = 0.001) and 24 weeks (5.5 vs. 3.2, P < 0.001). The study group had a shorter hospital stay (2.2 vs. 5.9, P < 0.001), and the net savings were HK$11,888 per patient.

CONCLUSION

It is feasible to integrate treatment into the real life environments of patients with diabetes, and nurse-led transitional care is a practical and cost-effective model. Nurse follow-up is effective in maintaining optimal glycaemic control and enhancing adherence to health behaviours. Management of glycaemic control is better done in the community than in the hospital.

Characterising atherothrombosis in Hong Kong: results of the Hong Kong data from a global atherothrombosis epidemiological survey

OBJECTIVES

To describe the characteristics of patients in Hong Kong with or at risk of atherothrombosis, to determine the proportion of symptomatic patients with more than one vascular bed affected, and to assess the relationship between ankle brachial index and disease severity.

DESIGN

Local participation in an international prevalence study.

SETTING

Five centres in Hong Kong.

PARTICIPANTS

A total of 210 subjects were recruited (105 women and 105 men). Patients were divided into the symptomatic group (with current or previous atherothrombotic symptoms, n=101) and at-risk group (with no current or previous symptoms, but aged over 55 years with at least two specified risk factors, n=109).

MAIN OUTCOME MEASURES

Patient characteristics were described, including the number of arterial beds affected, ankle brachial index, presence of risk factors, and medications taken.

RESULTS

Of the symptomatic patients, 30% had more than one arterial bed involved. A total of 55.4% of the symptomatic group and 18.4% of the at-risk group had abnormal ankle brachial index values. Lower ankle brachial indices were associated with a greater number of affected arterial beds. Diabetes mellitus and hypertension were the most prevalent risk factors in the at-risk group. Symptomatic patients were commonly treated with antihypertensive and antiplatelet agents, whereas at-risk patients were mostly treated with antihypertensive and antidiabetic agents. Only 20% of at-risk patients were taking antiplatelet agents.

CONCLUSIONS

Ankle brachial index is a useful tool for predicting those at risk of atherothrombosis. This simple measurement can be used as part of the screening process in the general practice. The role of antiplatelet agents in primary prevention of atherothrombotic events in at-risk patients deserves further attention.

Genetic and clinical characteristics of maturity-onset diabetes of the young in Chinese patients

In Caucasians, maturity-onset diabetes of the young (MODY) is mostly caused by mutations in the hepatocyte nuclear factor (HNF)-1alpha (MODY3) and glucokinase (MODY2) genes. Most Japanese MODY patients, however, are not linked to known MODY genes. In this study, we examined the genetic and clinical characteristics of Chinese subjects with MODY. The study included 146 unrelated families fulfilling the minimum criteria for MODY: two consecutive generations of type II diabetes with at least one member diagnosed under the age of 25. We screened for mutations in the HNF-4alpha (MODY1), MODY2 and MODY3 genes by direct sequencing. Antibody to glutamic acid decarboxylase (GAD-Ab) was measured in subjects with MODY of unknown cause (MODYX). Insulin resistance index and other clinical data were compared in sex-, age- and duration-matched MODY3 and MODYX patients. In all, 13 families had MODY3 mutations and two had MODY2 mutations. No MODY1 mutation was found. Four of the 12 different MODY3 mutations were newly identified novel mutations (Q243E, A311D, P379R and P488fsdelC). In subjects with MODYX, 3% were GAD-Ab positive and 60% were overweight. Compared to MODY3 patients, MODYX patients had higher body mass index (P<0.02), higher insulin resistance index (P=0.001) and triglyceride level (P<0.02), lower HDL level (P=0.001) and more hypertension (P<0.05), but no significant difference in the prevalence of diabetic complications. In conclusion, MODY3 and MODY2 account for only 9 and 1%, respectively, of Chinese MODY. A majority of Chinese MODY patients are due to defects in unknown genes and appear to be characterized by insulin resistance.

The use of recombinant human epidermal growth factor (rhEGF) in a gentleman with drug-induced Steven Johnson syndrome

A case of drug-induced Steven Johnson syndrome in a gentleman is reported. Its course of treatment with rhEGF was compared to conventional treatment in historical control.

Regulation of epididymal principal cell functions by basal cells: role of transient receptor potential (Trp) proteins and cyclooxygenase-1 (COX-1)

The epithelia lining the epididymides of many species including the human are known to consist of several cell types. Among them, the principal cells are the most abundant and their functions most extensively studied. There are other cell types such as the narrow cells, clear cells, halo cells and basal cells which are scattered along the duct in lesser number. Although these minority cell types have not been studied to the same extent as the principal cells, it is conceivable that their presence are essential to the integrated functions of the epididymis. In the intact epididymis, basal cells can be seen adhering to the basement membrane forming close contact with the principal cells above them. Work in our laboratory has provided evidence that through local formation of prostaglandins, basal cells may regulate electrolyte and water transport by the principal cells. This regulatory process involves two proteins which are exclusively expressed by the basal cells. They are the transient receptor potential (Trp) proteins, which serve as transmembrane pathways for Ca(2+) influx, and cyclooxygenase 1 (COX-1), a key enzyme in the formation of prostaglandins. The role of the two proteins in the integrated functions of the basal cells as humoral regulators of principal cells is discussed.

Human epidermal growth factor enhances healing of diabetic foot ulcers

OBJECTIVE

To study the healing effect of recombinant human epidermal growth factor (hEGF) on diabetic foot ulcers.

RESEARCH DESIGN AND METHODS

A total of 127 consecutive patients were screened and 61 diabetic subjects were recruited into this double-blind randomized controlled study. Predetermined criteria were used for diagnosis and classification of the diabetic wound. The patients were randomized into three groups. All patients attended our Diabetes Ambulatory Care Center every other week for joint consultation with the diabetologist and the podiatrist. Group 1 (control) was treated with Actovegin 5% cream (Actovegin), group 2 with Actovegin plus 0.02% (wt/wt) hEGF, and group 3 with Actovegin plus 0.04% (wt/wt) hEGF. The study end point was the complete closure of the wound. Failure to heal was arbitrarily defined as incomplete healing after 12 weeks.

RESULTS

Final data were obtained from 61 patients randomly assigned into three groups. The mean ages of the patients, wound sizes, wound duration, metabolic measurements, and comorbidities were comparable within groups, except that group 3 had more female patients. Mean follow-up for the patients was 24 weeks. Data were cutoff at 12 weeks, and results were analyzed by intention to treat. After 12 weeks, in group 1 (control) eight patients had complete healing, two patients underwent toe amputation, and nine had nonhealing ulcers. In group 2 (0.02% [wt/wt] hEGF) 12 patients experienced wound healing, 2 had toe amputations, and 7 had nonhealing ulcers. Some 20 of 21 patients in group 3 (0.04% [wt/wt] hEGF) showed complete wound healing. Healing rates were 42.10, 57.14, and 95% for the control, 0.02% (wt/wt) hEGF, and 0.04% (wt/wt) hEGF groups, respectively. Kaplan-Meier survival analysis suggested that application of cream with 0.04% (wt/wt) hEGF caused more ulcers to heal by 12 weeks and increased the rate of healing compared with the other treatments (log-rank test, P = 0.0003).

CONCLUSIONS

Our data support the contention that application of hEGF-containing cream, in addition to good foot care from a multidisciplinary team, significantly enhances diabetic foot ulcer wound healing and reduces the healing time.

Improvement in diabetes control with a monitoring system based on a hand-held, touch-screen electronic diary

We conducted a six-month prospective interventional crossover study examining a computerized diabetes monitoring system (DMS) that conveyed dietary information. The objectives were to compare glycaemic control between intervention and control periods, and to assess patients' acceptance of the DMS. Nineteen patients were randomized into two groups, each using the DMS for three months and serving as the control group for another three months. The patients recorded information about their meal portions and blood glucose readings in a hand-held electronic diary. After transmitting the data to the DMS through a telephone modem, the patients received immediate feedback about the carbohydrate, protein and fat content of the meal, as well as the calorie content. A significant improvement in glycaemic control was achieved during intervention compared with control periods (mean HbA1C reduction of 0.825%). The DMS was also highly acceptable: 95% patients found it easy to operate while 63% found it useful. The DMS was thus a feasible model of telemedicine in diabetes care and a larger study is warranted to examine its cost-effectiveness.

Sporadic bilateral adrenal medullary hyperplasia: apparent false positive MIBG scan and expected MRI findings

Adrenal medullary hyperplasia is a rare cause of clinical symptoms and biochemical findings identical to pheochromocytoma occurring mostly in multiple endocrine neoplasia patients. The scenario of positive MIBG scan, but no focal lesion found on CT and MRI led to diagnostic and management difficulties. Like pheochromocytoma, surgical excision can lead to clinical and biochemical recovery. We report this unusual case of sporadic bilateral adrenal medullary hyperplasia, with hypertension and biochemical abnormalities alleviated after surgical adrenalectomy. Based on T2 values reported in literature, high signal focal lesions may not appear on T2-weighted MRI images until development of frank pheochromocytoma. MIBG scan remains the most sensitive imaging modality for this condition.

Acarbose in NIDDM patients with poor control on conventional oral agents. A 24-week placebo-controlled study

OBJECTIVE

To determine the efficacy of acarbose, compared with placebo, on the metabolic control of NIDDM patients inadequately controlled on maximal doses of conventional oral agents.

RESEARCH DESIGN AND METHODS

In this three-center double-blind study, 90 Chinese NIDDM patients with persistent poor glycemic control despite maximal doses of sulfonylurea and metformin were randomly assigned to receive additional treatment with acarbose 100 mg thrice daily or placebo for 24 weeks, after 6 weeks of dietary reinforcement. Efficacy was assessed by changes in HbA1c, fasting and 1-h postprandial plasma glucose and insulin levels, and fasting lipid levels.

RESULTS

Acarbose treatment was associated with significantly greater reductions in HbA1c (-0.5 +/- 0.2% vs. placebo 0.1 +/- 0.2% [means +/- SEM], P = 0.038), 1-h postprandial glucose (-2.3 +/- 0.4 mmol/l vs. placebo 0.7 +/- 0.4 mmol/l, P < 0.001) and body weight (-0.54 +/- 0.32 kg vs. placebo 0.42 +/- 0.29 kg, P < 0.05). There was no significant difference between the two groups regarding changes in fasting plasma glucose and lipids or fasting and postprandial insulin levels. Flatulence was the most common side effect (acarbose vs. placebo: 28/45 vs. 11/44, P < 0.05). One patient on acarbose had asymptomatic elevations in serum transaminases that normalized in 4 weeks after acarbose withdrawal. Another patient on acarbose developed severe hypoglycemia; glycemic control was subsequently maintained on half the baseline dosage of sulfonylurea.

CONCLUSIONS

In NIDDM patients inadequately controlled on conventional oral agents, acarbose in moderate doses resulted in beneficial effects on glycemic control, especially postprandial glycemia, and mean body weight. Additional use of acarbose can be considered as a useful alternative in such patients if they are reluctant to accept insulin therapy.

Stable and temperature-sensitive transformation of rat kidney epithelial cells suppresses expression of acidic fibroblast growth factor 1 but activates secretion of fibroblast growth factor 3 (int-2) and vascular endothelial growth factor

Rat kidney proximal tubule epithelial cells (RPTE) in primary culture express acidic fibroblast growth factor 1 (FGF-1). Transformation of RPTE by SV40 (SV-RPTE) suppressed FGF-1 expression but activated secretion of FGF-like factor(s). SV-RPTE conditioned medium contained growth-promoting activity for SV-RPTE and human umbilical vein endothelial cells, indicating that both autocrine and angiogenic factors were secreted. Reverse transcriptase-polymerase chain reaction and Northern analysis for various FGFs showed that only FGF-3, also known as int-2, mRNA was expressed in SV-RPTE. In addition, expression of mRNA for the heparin-binding angiogenic factor vascular endothelial growth factor (VEGF) increased dramatically in SV-RPTE. Physical characterization of the activity in the SV-RPTE conditioned medium suggested that FGF-3 and VEGF contributed the autocrine and angiogenic activities, respectively. We also investigated FGF-3 and VEGF secretion in temperature-sensitive (ts) SV40-transformed RPTE. tsSV-RPTE had transformed properties resembling those of SV-RPTE only at the permissive temperature (33 degrees C), e.g., increased growth potential and anchorage-independent growth. FGF-1 was expressed only at the nonpermissive temperature. VEGF mRNA levels and secretion of the human umbilical vein endothelial cell growth-promoting activity were reduced by switching tsSV-RPTE cells from 33 degrees to 39 degrees C. However, FGF-3 mRNA levels were not affected significantly by the temperature switch suggesting that activation of VEGF and FGF-3 occurs through different mechanisms. These results indicate that FGF-1 expression in RPTE is suppressed by SV40 transformation.(ABSTRACT TRUNCATED AT 250 WORDS)