Comparative Effectiveness RCT of Two Weight Loss Strategies in Primary Care Patients: MyPlate.gov vs Calorie Counting.

Context: Since 2011, the U.S. government has supported two approaches to achieve healthier body fat composition: the Diabetes Prevention Program calorie counting (CC) approach, and adherence to federal nutrition guidelines at www.choosemyplate.gov (MyPlate). Objective: Compare the effect of the CC versus MyPlate approach on satiety/satiation and on achieving healthier body fat composition in the primary care setting. Study Design: Randomized, controlled trial comparing the MyPlate and CC approaches from 2015 to 2017. Setting: A federally qualified health center in Long Beach, California. Population: Adult, low-income, mostly Latina patients (N=261) with a BMI between 27 and 40.4 were randomized to condition and followed for twelve months (76.6% retention). Interventions: Eleven health education sessions featuring MyPlate versus CC messages. Community health workers conducted two home visits, two group education sessions and 7 telephone coaching calls over six months. Outcome Measures: Satiation and satiety were primary patient-centered outcomes. Waist circumference and body weight were primary anthropometric measures. These were assessed at baseline, 6- and 12-months follow-up. Results: Satiation and satiety scores increased for both groups; neither group lost significant body weight, and only the MyPlate condition reduced waist circumference by 2 cm at 12 months. Both conditions reported consuming proportionately more fruits and vegetables and fewer sugary beverages at 12 months. MyPlate but not CC participants experienced lower systolic blood pressure at 6 months follow-up; neither group had lower blood pressure at 12 months. Both MyPlate and CC participants reported higher quality of life and emotional well-being at 12 months and high satisfaction with their assigned weight loss program. At 12 months follow-up, the most acculturated participants experienced the greatest reduction in waist circumference. Conclusions: A MyPlate-based intervention may be a practical alternative to the more traditional CC approach to promoting satiety and facilitating reduction in central adiposity among low-income mostly Latina overweight primary care patients. Our results align with recommendations favoring a diet rich in diverse, fiber-rich foods. More research is warranted to investigate satiety-enhancing approaches to desirable weight control in diverse populations and the use of community health workers as change agents.

Fuzzy neural-based control for nonlinear time-varying delay systems.

In this paper, a partially known nonlinear dynamic system with time-varying delays of the input and state is approximated by N fuzzy-based linear subsystems described by a state-space model with average delay. To shape the response of the closed-loop system, a set of fuzzy reference models is established. Similarly, the same fuzzy sets of the system rule are employed to design a fuzzy neural-based control. The proposed control contains a radial-basis function neural network to learn the uncertainties caused by the approximation error of the fuzzy model (e.g., time-varying delays and parameter variations) and the interactions resulting from the other subsystems. As the norm of the switching surface is inside of a defined set, the learning law starts; in this situation, the proposed method is an adaptive control possessing an extra compensation of uncertainties. As it is outside of the other set, which is smaller than the aforementioned set, the learning law stops; under this circumstance, the proposed method becomes a robust control without the compensation of uncertainties. A transition between robust control and adaptive control is also assigned to smooth the possible discontinuity of the control input. No assumption about the upper bound of the time-varying delays for the state and the input is required. However, two time-average delays are needed to simplify the controller design: 1) the stabilized conditions for every transformed delay-free subsystem must be satisfied; and 2) the learning uncertainties must be relatively bounded. The stability of the overall system is verified by Lyapunov stability theory. Simulations as compared with a linear transformed state feedback with integration control are also arranged to consolidate the usefulness of the proposed control.