Self-reported hypoglycaemia in insulin-treated patients with diabetes mellitus: results from the Singapore cohort of the International Operations Hypoglycaemia Assessment Tool study.

INTRODUCTION: Hypoglycaemia constitutes a significant barrier to achieving glycaemic control with insulin in both Type 1 (T1DM) and Type 2 diabetes mellitus (T2DM). The International Operations Hypoglycaemia Assessment Tool (IO HAT) study was designed to determine the incidence of hypoglycaemia in insulin-treated patients with T1DM and T2DM. METHODS: The IO HAT study retrospectively and prospectively assessed the incidence of hypoglycaemia in patients with insulin-treated diabetes mellitus in nine countries. This sub-analysis included patients from Singapore with T1DM or T2DM who were aged ≥ 21 years and had completed two self-assessment questionnaires (SAQ1 and SAQ2). RESULTS: Of the 50 T1DM and 320 T2DM patients who completed the SAQ1, 39 T1DM and 265 T2DM patients completed SAQ2; 100% and 90.9%, respectively, experienced at least one hypoglycaemic event prospectively. The incidence rates of any hypoglycaemia were 49.5 events per patient-year (EPPY) and 16.1 EPPY for T1DM and T2DM patients, respectively, in the four-week prospective period. Hypoglycaemia rate did not differ in terms of glycated haemoglobin level. The vast majority of T1DM or T2DM patients (92.0% and 90.7%, respectively) knew the overall definition of hypoglycaemia before study participation, although over half of the patients (T1DM 54.0%, T2DM 51.9%) defined hypoglycaemia based only on symptoms. CONCLUSION: High proportions of insulin-treated patients with diabetes mellitus in Singapore reported hypoglycaemic events prospectively, showing that they had underreported hypoglycaemic episodes retrospectively. Patient education can help in improving hypoglycaemia awareness and its management in the region.

Mean Rank, Equipercentile, and Regression Mapping of World Health Organization Quality of Life Brief (WHOQOL-BREF) to EuroQoL 5 Dimensions 5 Levels (EQ-5D-5L) Utilities.

BACKGROUND: Existing methods to link preference-based and profile-based health-related quality of life (HRQoL) questionnaires have their limitations. Hence, we developed a new mapping method (the mean rank method, MRM) and applied it to map the World Health Organization Quality of Life Questionnaire (WHOQOL-BREF) to the EuroQoL 5 Dimensions 5 Levels (EQ-5D-5L). We then compared the new MRM with current methods; i.e., regression-mapped (OLS method) and equipercentile method (EPM). METHODS: Singapore residents, aged ≥21 y, were recruited from the general population and 2 outpatient clinics in acute care hospitals. Performance of the MRM was evaluated using both simulation and split-sample validation ( n = 658 in training and n = 657 in validation samples). Using the training sample, we derived 3 sets of mapped EQ-5D-5L utilities based on MRM, OLS method and EPM. Using simulation and the validation sample, we compared the performance of the mapping methods in terms of distribution parameters, mean utility by strata, association with health covariates, and prediction errors at the individual level, among others. RESULTS: The WHOQOL-BREF Physical Health domain is the only domain significantly associated with EQ-5D-5L utilities. Simulation showed that MRM more accurately reproduced the variance and percentiles of the distribution of the observed utilities than did the OLS method or EPM. OLS method tended to underestimate the mean utility of good health states, overestimate the mean utility of poor health states, and underestimate the association with covariates. An analysis of validation sample gave similar results. CONCLUSION: In scenarios similar to the mapping of WHOQOL-BREF to the EQ-5D-5L, the MRM outperformed the OLS method and EPM in important-though not all-aspects. The simplicity and reproducibility of the MRM makes it an attractive alternative to current methods.

Validation of prediction equations for resting energy expenditure in Singaporean Chinese men.

Accurate prediction of resting energy expenditure (REE) is important in establishing adequate dietary intake goals for effective weight management. Previous studies have shown that the validity of an energy prediction equation may depend on the ethnicity of the population. Validation studies are lacking in the Singaporean Chinese population. A total of 96 healthy Singaporean Chinese males of age 21­40 years and body mass index (BMI) 18.5­30.0 kg/m2 participated in this study. REE was measured by indirect calorimetry and compared with REE predicted using existing equations. Validity was evaluated on the basis of mean bias and percentage of subjects predicted within ±10% of REE measured. In addition, Bland and Altman analyses were performed. No significant difference was observed between the mean levels of measured and predicted REE derived from the Owen equation. The Food and Agriculture Organization/World Health Organization/United Nations University (FAO/WHO/UNU), Harris­Benedict and Mifflin equations significantly overestimated the mean measured REE by 7.5%, 6.0% and 2.4% respectively. Percentage of valid predictions for FAO/WHO/UNU, Harris­Benedict, Mifflin and Owen equations were 60%, 67%, 75% and 73% respectively. Bland and Altman analyses demonstrated poor agreement for all equations. The Owen equation provided a valid estimation of REE in Singaporean Chinese men at a group level. However, the individual errors of the equations were unacceptable high and may have limited utility in making clinical decisions on nutritional requirements.