The Impact of Overweight/Obesity Duration and Physical Activity on Medical Multimorbidity: Examining the WATCH Paradigm.

PURPOSE: The "fat-but-fit" paradigm has been evaluated. However, the duration of overweight/obesity within the "fat-but-fit" paradigm (ie, assessing body mass at more than 1 time point) has not been extensively evaluated, which was this study's purpose.

DESIGN: Cross-sectional.

SETTING: National Health and Nutrition Examination Survey 2003 to 2006.

PARTICIPANTS: Ages 36 to 85; N = 3621.

MEASURES: Physical activity assessed via accelerometry. Medical multimorbidity was assessed via physician diagnosis of 13 chronic diseases. Height and body mass were directly measured for current body mass index (BMI), and 10-year prior BMI was calculated using current height and self-reported weight 10 years prior. Six mutually exclusive groups were created: (1) active, normal weight now and 10 years ago; (2) inactive, normal weight now and 10 years ago; (3) active, overweight/obese now but not 10 years ago; (4) active, overweight/obese now and 10 years ago; (5) inactive, overweight/obese now but not 10 years ago; and (6) inactive, overweight/obese now and 10 years ago.

ANALYSIS: Logistic regression.

RESULTS: Compared to group 1, adjusted odds ratios (ORs) were as follows: group 2: OR = 2.0 ( P = .004), group 3: OR = 1.7 ( P = .004), group 4: OR = 2.5 ( P < .001), group 5: OR = 2.9 ( P < .001), and group 6: OR = 4.8 ( P < .001).

CONCLUSIONS: All patterns of weight change/duration and activity level altered the odds of medical multimorbidity, suggesting that the duration of overweight/obesity should also be taken into consideration when assessing the "fat-but-fit" paradigm.