Secular trends in the diagnosis and treatment of obesity among US adults in the primary care setting.

Excess weight afflicts the majority of the US adult population. Research suggests that the role of primary care physicians in reducing overweight and obesity is essential; moreover, little is known about self-care of obesity. This report assessed the secular trends in the care of overweight and investigated the secular association between obesity with care of overweight in primary care and self-care of overweight. Cross-sectional evaluation of the National Health and Nutrition Examination Survey (NHANES) III (1988-1994) and the Continuous NHANES (1999-2008) was employed; the total sample comprised 31,039 nonpregnant adults aged 20-90 years. The relationship between diagnosed overweight, and directed weight loss with time and obesity was assessed. Despite the combined secular increase in the prevalence of overweight and obesity (BMI >25.0 kg/m(2)) between 1994 and 2008 (56.1-69.1%), there was no secular change in the odds of being diagnosed overweight by a physician when adjusted for covariates; however, overweight and obese individuals were 40 and 42% less likely to self-diagnose as overweight, and 34 and 41% less likely to self-direct weight loss in 2008 compared to 1994, respectively. Physicians were also significantly less likely to direct weight loss for overweight and obese adults with weight-related comorbidities across time (P < 0.05). Thus, the surveillance of secular trends reveals that the likelihood of physician- and self-care of overweight decreased between 1994 and 2008 and further highlights the deficiencies in the management of excess weight.