Increasing trends in waist circumference and abdominal obesity among US adults.
Level 4 - case-series / case-control
Serial cross-sectional survey analysis (NHANES)
PubMed 17228050 · doi:10.1038/oby.2007.505
What was done
Data from the National Health and Nutrition Examination Survey across four time intervals (1988-1994, 1999-2000, 2001-2002, and 2003-2004) were analyzed to evaluate trends in age-adjusted mean waist circumference and the prevalence of abdominal obesity among US adults. Differences between survey cycles were tested using pooled t tests.
What was found
Between 1988-1994 and 2003-2004, age-adjusted mean waist circumference increased from 96.0 cm to 100.4 cm in men (p < 0.001) and from 89.0 cm to 94.0 cm in women (p < 0.001). The age-adjusted prevalence of abdominal obesity rose from 29.5% to 42.4% in men (p < 0.001) and from 47.0% to 61.3% in women (p < 0.001). Between 1999-2000 and 2003-2004, waist circumference rose significantly only in men (99.0 cm to 100.4 cm; p = 0.03), whereas abdominal obesity prevalence rose in both men (37.0% to 42.2%; p = 0.03) and women (55.3% to 61.3%; p = 0.04). Over half of US adults had abdominal obesity by 2003-2004, with a greater relative increase observed among individuals with a BMI of 25 to 29 kg/m2.
Why it matters
These findings show a continuous 15-year expansion of abdominal obesity across the US adult population, which confers elevated cardiometabolic and mortality risks.
Limits
The total sample size is not reported in the abstract. The study relies on serial cross-sectional datasets rather than tracking individuals longitudinally, and clinical health outcomes were not evaluated in the abstract.
Cited by
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