First ARHP ‘Best of the Meeting’ Highlights Sleep Research, Osteoporosis Screening, More

Alternatives to Body Mass Index

Body mass index (BMI), although the standard measure of obesity, has shown high variability in certain subgroups and tends to underestimate obesity in older adults. Now, the authors of an abstract presented at the ARHP Epidemiology and Public Health I session (abstract 799) conclude that BMI also does not accurately reflect body composition in patients with rheumatoid arthritis (RA).

“It turns out that BMI isn’t the greatest tool to assess obesity in everyone,” Dr. McLean said. “The researchers found a huge discrepancy between BMI and [dual-energy X-ray absorptiometry] DEXA.”

Presenter Patricia P. Katz, PhD, of the University of California, San Francisco, and her colleagues measured body composition in approximately 140 RA-affected patients.

They compared measurements using BMI, waist circumference, and DEXA, which calculated the percentages of muscle mass and fat mass. Among the men, DEXA classified 80% of them as obese, compared with only 29% being classified by BMI; the percentage of women classified as obese was 44% with DEXA vs. 26% with BMI.

Patients with RA had higher trunk fat and lower appendicular muscle mass, which caused Dr. McLean to speculate that waist circumference would be a better measure of obesity in this population. However, he said the investigators found that waist circumference was no better than BMI at assessing body composition in these patients.

“[The presenter] had no explanation for this,” he added. “There is a lot more work to be done looking at measures of body composition in patients with RA.”

Osteoporosis Screening

Two studies presented at the Clinical Practice/Patient Care I session evaluated osteoporosis assessment or screening. Maria Antonelli, MD, of Case Western Reserve University in Cleveland, and her colleagues studied 420 patients with a primary diagnosis of hip fracture not due to cancer or Paget disease (abstract 870).

They found that physicians ordered DEXA after hospital discharge in less than 14% of these patients. “This is evidence that people are not being assessed enough for osteoporosis, even when they know they have a hip fracture,” Dr. McLean said.

Another study showed more hopeful findings, according to Dr. McLean. Presented by Kori A. Dewing, DNP, ARNP, of Virginia Mason Medical Center in Seattle, the study (abstract 869) evaluated the effect of a clinical-decision support system on rates of DEXA bone mineral density screening in 65-year-old women.