Factors predictive of drop-out and weight loss success in weight management of obese patients

Background: The prevention and treatment of overweight and obese individuals on a population-wide basis is challenging because patients have difficulties with adhering to weight loss programmes. The present study aimed to evaluate patients' adherence to the weight reduction programme by identifying factors predictive of both drop-out rate and weight loss success. Methods: One-hundred and twenty-four obese patients participated in a 12-month weight reduction programme, involving group therapy during an intensive 5-day educational intervention, followed by five, 2-h follow-up visits. The primary outcome measures included drop-out rate and percentage weight loss. Sociodemographic and clinical characteristics, as well as type of diet, were explored as potential predictive factors. Type of diet was assigned based on randomisation. Regression analyses were conducted to identify predictive variables of drop-out and weight loss success. Results: In total, 33.1% of all recruited participants were deemed successful because they reduced the initial weight by more than 5% after the 12-month intervention. The overall attrition rate was 32.3%. In a multiple regression model, initial weight loss and marital status were the strongest predictors of weight loss success after 1-year period (r(2) = 0.481, P < 0.001). In a separate analysis, subjects more likely to drop-out were those with a lower educational level [odds ratio (OR) = 3.26, 95% confidence interval (CI) = 1.22-8.70, P = 0.018] and a higher level of obesity (OR = 0.974, 95% CI = 0.95-0.99, P = 0.010). Conclusions: The present study demonstrates that initial weight loss at 1 month made the strongest unique contribution to the prediction of percentage weight loss after 12 months, whereas being married was a negative predictor. Those with a lower educational level and a higher level of obesity were more likely to drop-out.