Traditional Measures Miss Obesity in Women With Lupus
Revision of anthropometric obesity measure cut-offs to match dual X-ray absorptiometry criteria
MONDAY, Feb. 14 (HealthDay News) -- Obese women with systemic lupus erythematosus (SLE) may be misclassified by anthropometric measures. Dual X-ray absorptiometry (DXA) can be used to adjust the traditional guidelines to improve diagnostic accuracy, according to a study published in the February issue of Arthritis Care & Research.
Patricia Katz, Ph.D., from the University of California in San Francisco, collected data on DXA, height, weight, and waist and hip circumference from 145 women with SLE. DXA-based obesity data was compared to three obesity measurement cut-off points: body mass index (BMI) ≥30 kg/m²; waist circumference ≥88 cm; and waist-to-hip ratio ≥0.85. An optimal cut point was determined for each measure relative to DXA. Cardiovascular risk was assessed based on the obesity measurements.
The investigators found that according to DXA, 50 percent of the women were obese, but these numbers dropped to 28 percent using waist circumference, 29 percent using BMI, and 41 percent using waist-to-hip ratio. The women misclassified based on anthropometric criteria had less fat on their trunk and extra appendicular lean and fat mass. The revised guidelines, adjusted to match the DXA, were BMI ≥26.8 kg/m²; waist circumference ≥84.75 cm; and waist-to-hip ratio ≥0.80. Increased cardiovascular risk was noted using both criteria of obesity measurements.
"Our results suggest that cardiovascular risk of women who meet the revised obesity criterion is equivalent to that of women who meet traditional anthropometric obesity criteria, and that the traditional criteria may underestimate obesity-related cardiovascular risk," the authors write.