Supplementary Material for: Validity of the Use of a Triaxial Accelerometer and a Physical Activity Questionnaire for Estimating Total Energy Expenditure and Physical Activity Level among Elderly Patients with Type 2 Diabetes Mellitus: CLEVER-DM Study

Introduction: Evaluation of total energy expenditure (TEE) and physical activity level (PAL) is important for treatment of patients with type 2 diabetes mellitus (T2DM). However, the validity of accelerometers (ACC) and physical activity questionnaires (PAQ) for estimating TEE and PAL remains unknown in elderly populations with T2DM. We evaluated the accuracy of TEE and PAL results estimated by an ACC (TEE_ACC and PAL_ACC) and a PAQ (TEE_PAQ and PAL_PAQ) in elderly patients with T2DM. Methods: Fifty-one elderly patients with T2DM (aged 61–79 years) participated in this study. TEE_ACC was calculated with PAL_ACC using a triaxial ACC (Active style Pro HJA-750c) over 2 weeks and predicted basal metabolic rate (BMR) by Ganpule’s equation. TEE_PAQ was estimated using predicted BMR and the PAL_PAQ from the ­Japan Public Health Center Study-Long questionnaire. We compared the results to TEE_DLW measured with the doubly labeled water (DLW) method and PAL_DLW calculated with BMR using indirect calorimetry. Results: TEE_DLW was 2,165 ± 365 kcal/day, and TEE_ACC was 2,014 ± 339 kcal/day; TEE_ACC was strongly correlated with TEE_DLW (r = 0.87, p < 0.01) but significantly underestimated (–150 ± 183 kcal/day, p < 0.05). There was no significant difference in TEE_PAQ and TEE_DLW (–49 ± 284 kcal/day), while the range of difference seemed to be larger than TEE_ACC. PAL_DLW, PAL_ACC, and PAL_PAQ were calculated to be 1.71 ± 0.17, 1.69 ± 0.16, and 1.78 ± 0.24, respectively. ­PAL_ACC was strongly correlated with PAL_DLW (r = 0.71, p < 0.01), and there was no significant difference between the 2 values. PAL_PAQ was moderately correlated with PAL_DLW (r = 0.43, p < 0.01) but significantly overestimated. Predicted BMR was significantly lower than the BMR ­measured by indirect calorimetry (1,193 ± 186 vs. 1,262 ± 155 kcal/day, p < 0.01). Conclusions: The present ACC and questionnaire showed acceptable correlation of TEE and PAL compared with DLW method in elderly patients with T2DM. Systematic errors in estimating TEE may be improved by the better equation for predicting BMR.