Cross-cultural comparison of predictors for self-care behaviors in patients with type 2 diabetes.

The aim of the present study was to evaluate how culture moderates the behavioral and psychosocial predictors of diabetes self-care activities. Patients with type 2 diabetes were recruited in the outpatient department at two sites: Kyoto University hospital in Japan and the Christiana Care Health System in the USA. The data were collected by survey using questionnaires including questions on the frequency of self-care activities, behavioral and psychosocial predictors, and other background information from 149 Japanese patients and 48 American patients. The cultural impact was observed by multiple regression analyses with interaction terms on the association between emotional support and self-care activities in diet in female patients. The findings of the present study serve as an example of how cultural context can affect patients with diabetes, and lead to a better understanding of culturally sensitive behavioral intervention.

Carbohydrate intake is associated with time spent in the euglycemic range in patients with type 1 diabetes.

AIMS/INTRODUCTION: Greater glycemic variability and lack of predictability are important issues for patients with type 1 diabetes. Dietary factors are one of the contributors to this variability, but how closely diet is linked to glycemic fluctuation on a daily basis has not been investigated. We examined the association between carbohydrate intake and glycemic excursion in outpatients. MATERIALS AND METHODS: A total of 33 patients with type 1 diabetes were included in the analyses (age 44.5 ± 14.7 years, diabetes duration 15.1 ± 8.3 years, 64% female, 30% using insulin pump, glycated hemoglobin 8.1 ± 1.3%). Time spent in euglycemia (70-180 mg/dL), hyperglycemia (>180 mg/dL) and hypoglycemia (<70 mg/dL) of consecutive 48-h periods of continuous glucose monitoring data were collected together with simultaneous records of dietary intake, insulin dose and physical activity. Correlation analyses and multiple regression analyses were used to evaluate the contribution of carbohydrate intake to time spent in the target glycemic range. RESULTS: In multiple regression analyses, carbohydrate intake (ß = 0.53, P = 0.001), basal insulin dose per kg per day (ß = -0.31, P = 0.034) and diabetes duration (ß = 0.30, P = 0.042) were independent predictors of time spent in euglycemia. Carbohydrate intake (ß = -0.51, P = 0.001) and insulin pump use (ß = -0.34, P = 0.024) were independent predictors of time spent in hyperglycemia. Insulin pump use (ß = 0.52, P < 0.001) and bolus insulin dose per kg per day (ß = 0.46, P = 0.001) were independent predictors of time spent in hypoglycemia. CONCLUSIONS: Carbohydrate intake is associated with time spent in euglycemia in patients with type 1 diabetes.

Social orientation and diabetes-related distress in Japanese and American patients with type 2 diabetes.

OBJECTIVE: Recent evidence in cultural and social psychology suggests Eastern cultures' emphasis on harmony and connection with others and Western cultures' emphasis on self-direction and autonomy. In Eastern society, relational harmony is closely linked to people's well-being. The impact of this cultural and social orientation on diabetes-related distress was investigated. RESEARCH DESIGN AND METHODS: Japanese and American patients with type 2 diabetes were surveyed by well-established questionnaire in Japan and in the United States, respectively. The association of personal values for interdependence, perceived emotional support, and the Problem Areas in Diabetes scale (PAID) were analyzed. RESULTS: A positive correlation between interdependence and PAID (r = 0.18; P = 0.025) and a negative correlation between perceived emotional support and PAID (r = - 0.24; P = 0.004) were observed after adjustments for other factors in Japanese data (n = 149), but not in American data (r = 0.00; P = 0.990, r = 0.02; P = 0.917, respectively, n = 50). In Japanese data, the three-factor structure of PAID (negative feelings about total life with diabetes, about living conditions with diabetes, and about treatment of diabetes) was identified, and interdependence showed significant positive correlations with the first and second factors and perceived emotional support showed significant negative correlations with all three factors of PAID. CONCLUSIONS: These results suggest that personal values for interdependence may be linked to the level of diabetes-related distress and that the distress may be relieved by perception of emotional support, especially in an interdependent cultural context.

Utility of indices using C-peptide levels for indication of insulin therapy to achieve good glycemic control in Japanese patients with type 2 diabetes.

UNLABELLED: Aims/Introduction: Type 2 diabetes is progressive in that therapy must be altered over time, which is partly as a result of the progressive loss of pancreatic ß-cell function. To elucidate the relationship between residual endogenous insulin secretion and the necessity of insulin therapy to achieve good glycemic control, indices using serum C-peptide immunoreactivity (CPR) were analyzed in patients with type 2 diabetes. MATERIALS AND METHODS: The data of 201 Japanese patients with type 2 diabetes who achieved the target of glycemic control during admission were analyzed retrospectively. Indices using CPR including fasting CPR (FCPR), CPR 6 min after intravenous injection of glucagon (CPR-6 min), increment of CPR (ΔCPR), secretory unit of islet in transplantation index (SUIT) and C-peptide index (CPI) were compared between the group requiring insulin (insulin group) and the group not requiring insulin (non-insulin group). A receiver-operator characteristic (ROC) curve was made, and optimal cut-off point and likelihood ratio were determined for each index. RESULTS: All indices of CPR were lower in the insulin group compared with those in the non-insulin group. Likelihood ratios at the optimal point of FCPR, CPR-6 min, ΔCPR, SUIT, and CPI were 2.0, 2.1, 1.6, 2.3 and 2.8, respectively. Optimal cut-off point of CPI was 1.1 ng/mg. Sensitivity and specificity at optimal point of CPI were 61 and 78%, respectively. CONCLUSIONS: The advantage of CPI of the indices of CPR to select insulin therapy to achieve good glycemic control was shown, but limitations of the predictive abilities of the indices using CPR should be taken into account. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2010.00096.x, 2011).

Analysis of factors influencing postprandial C-peptide levels in Japanese patients with type 2 diabetes: Comparison with C-peptide levels after glucagon load.

UNLABELLED: Aims/Introduction: Postprandial serum C-peptide levels are readily determined in clinical practice and have a good correlation with serum C-peptide levels after glucagon load; the measurement is often used as an index of endogenous insulin secretion. However, the factors affecting postprandial serum C-peptide levels remain to be evaluated. MATERIALS AND METHODS: To investigate the clinical factors affecting postprandial serum C-peptide, 2-h postprandial C-peptide levels after breakfast (PPCPR) were analyzed retrospectively for comparison with glucagon-stimulated C-peptide (CPR-6min) levels measured during hospital admission in 273 Japanese patients with type 2 diabetes. RESULTS: Multiple regression analysis showed that years from diagnosis, body mass index (BMI) and HbA1c were the major independent variables predicting PPCPR (R (2) = 0.315). HbA1c was a major factor predicting PPCPR, but did not predict CPR-6min. In addition, HbA1c was negatively correlated with PPCPR (r = -0.410, P < 0.0001) and PPCPR/CPR-6min (r = -0.313, P < 0.0001). CONCLUSIONS: PPCPR was correlated with common factors predicting CPR, including years from diagnosis and BMI, but also was negatively correlated with HbA1c, a unique factor. These results show that chronic elevation of the glucose level might impair endogenous insulin secretion after meal load, but might have little effect on endogenous insulin secretion after glucagon load. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2011.00126.x, 2011).

Relationship between carotid intima-media thickness and silent cerebral infarction in Japanese subjects with type 2 diabetes.

OBJECTIVE: We examined the relationship between intima-media thickness of common carotid artery (CCA-IMT) and silent cerebral infarction (SCI) with the magnetic resonance imaging (MRI) study in Japanese subjects with type 2 diabetes. RESEARCH DESIGN AND METHODS: The brain MRI study and the carotid ultrasonography were performed in a total of 217 consecutive Japanese subjects with type 2 diabetes. Various risk factors for SCI were examined using multiple logistic analyses. RESULTS: The SCI was found in 60.4% of the diabetic subjects. In the diabetic subjects, age, systolic blood pressure (SBP), pulse wave velocity, and CCA-IMT were significantly higher in the subjects with SCI than in those without it. Multiple logistic analyses indicated that age, SBP, and CCA-IMT were significant and independent risk factors of SCI in the diabetic subjects. CONCLUSIONS: CCA-IMT, but not pulse wave velocity, was independently associated with SCI in Japanese subjects with type 2 diabetes.