BMI Irrelevant to Patient’s Outcome Awareness

When researchers from New York University (NYU) Langone Health examined data from 2,130 patients they were attempting to map the relationship between body mass index (BMI) and the postoperative Forgotten Joint Score-12 in patients undergoing primary total hip arthroplasty (THA).

Roy Davidovitch, M.D., the Julia Koch Associate Professor of Orthopedic Surgery at NYU Langone Health, was a co-author on the work, and told OTW, “Obesity is a national health crisis and we understand that obese patients may encounter more challenges postop, including complications. We wanted to assess if overweight patients achieved similar long term functional outcomes to non-obese patients.”

“The Forgotten Joint Score has been validated as an assessment tool for patients to see if they have forgotten their joint replacement, or stated differently, it assesses patients awareness of their joint replacement in their activities of daily living. It helps to get around the ceiling effects of the more traditional outcome scores. Our hypothesis was that obese patients would have greater awareness of their joint replacement, i.e., lower Forgotten Joint Scores.”

Patients were separated into “obese” and “non-obese” groups; Forgotten Joint Scores were calculated at 3, 12, and 24 months postoperatively.

All blissfully unaware of surgery?

Dr. Davidovitch: “The most important conclusions were that statistically there was no difference in the Forgotten Joint Scores of patients in both cohorts, i.e., the obese patients were just as unaware of their arthroplasty as compared to the non-obese patients. We did find a statistically significant difference in the delta change improvement, i.e., non-obese patients apparently improved their actual Forgotten Joint Scores more between the time intervals than the non-obese patients, however, although this was statistically significant it is likely not clinically significant.”

“We did perform a subgroup analysis among the obese cohorts, further dividing it into BMI 30-34.9, 35-39.9, >40 and did find that with increasing BMI class there was a smaller improvement of BMI.”

“Further analysis to see if any obesity related complications are reflected in Forgotten Joint Score. An analysis of patients who have had postop complications and their Forgotten Joint Scores would be helpful and this would require a much larger cohort.”