THA Triggers Changes in Obesity, Arthritis Over Time

Results of a 13-year study revealed obesity and medical and psychological comorbidities have increased over time, whereas underlying diagnoses of rheumatoid arthritis and inflammatory arthritis have fallen rapidly among patients undergoing total hip arthroplasty (THA).

Using data from the Mayo Clinic Total Joint Registry from 1993 to 2005, researchers from the Mayo Clinic, Birmingham VA Medical Center (Alabama) and the University of Alabama studied time-trends in demographics, including age and BMI; medical and psychological comorbidity; and patients’ diagnoses after undergoing.

Data were assessed for 6,168 patients, of whom 52 percent were women. Patients were between the ages of 50 and 80 years and were characterized as overweight, obese, very obese or extremely obese. The researchers used Chi-square test and analysis for variance, and multivariable-adjusted logistic regression was used to compare data from 1993 to 1995 with that of other study periods.

Results showed significant increases between the periods 1993 to 1995 and 2002 to 2005 in the percentage of patients with BMI of 40 or greater (2.3 percent vs. 6.3 percent), as well as in patients’ incidence of depression (4.1 percent vs. 9.8 percent) and anxiety (3.4 percent vs. 5.7 percent).

During the same comparison periods, however, fewer patients were diagnosed with rheumatoid/inflammatory arthritis (3.7 percent vs. 1.5 percent). Overall, arthritis was reduced by 65 percent to 75 percent in patients between the ages of 50 and 80 years, adding to growing evidence that THA is required by fewer patients with rheumatoid/inflammatory arthritis compared with one to two decades previously, according to the study.

The Deyo-Charlson Index, used to measure patients’ medical comorbidities, increased by 22 percent during the 13-year period. The researchers also observed a reduction in the mean age for patients needing THA.