ABSTRACT
INTRODUCTION: Nearly 50 % of patients with chronic medical illness exhibit poor treatment adherence. When making treatment decisions, these patients must balance the probability of current side effects against the probability of long-term benefits. This study examines if the behavioral economic construct of probability discounting can be used to explain treatment decisions in chronic disease. METHODS: Thirty-eight nonadherent and 39 adherent patients with multiple sclerosis (MS) completed a series of hypothetical treatment scenarios with varied risk and benefit probabilities. RESULTS: As described by a hyperbolic probability discounting model, all patients reported decreased medication initiation as the probability of treatment efficacy decreased and the probability of treatment side effects increased. When compared to adherent patients, nonadherent patients significantly devalued treatment efficacy and inflated treatment risk. DISCUSSION: The methods in this study can be used to identify optimal risk/benefit ratios for treatment development and inform the process by which patients make treatment decisions.
Subject(s)
Decision Making/physiology , Delay Discounting , Multiple Sclerosis/psychology , Patient Compliance/psychology , Reward , Adult , Female , Humans , Male , Middle Aged , Multiple Sclerosis/drug therapy , Treatment OutcomeABSTRACT
OBJECTIVE: Few studies have examined brain changes in response to effective weight loss; none have compared different methods of weight-loss intervention. Functional brain changes associated with a behavioral weight loss intervention to those associated with bariatric surgery were compared. DESIGN AND METHODS: Fifteen obese participants were recruited prior to adjustable gastric banding surgery and 16 obese participants were recruited prior to a behavioral diet intervention. Groups were matched for demographics and amount of weight lost. Functional magnetic resonance imaging scans (visual food motivation paradigm while hungry and following a meal) were conducted before and 12 weeks after surgery/behavioral intervention. RESULTS: When compared to bariatric patients in the premeal analyses, behavioral dieters showed increased activation to food images in right medial prefrontal cortex (PFC) and left precuneus following weight loss. When compared to behavioral dieters, bariatric patients showed increased activation in bilateral temporal cortex following weight loss. CONCLUSIONS: Behavioral dieters showed increased responses to food cues in medial PFC-a region associated with valuation and processing of self-referent information-when compared to bariatric patients. Bariatric patients showed increased responses to food cues in brain regions associated with higher level perception-when compared to behavioral dieters. The method of weight loss determines unique changes in brain function.
