| Demographic Group: |
Resident persons aged ≥18 years. |
| Numerator: |
Respondents aged ≥18 years who report doctor-diagnosed arthritis and who are obese (body mass index≥30.0 kg/m²), calculated from self-reported weight and height. |
| Denominator: |
Respondents aged ≥18 years who are obese (body mass index≥30.0 kg/m² calculated from self-reported weight and height). (excluding unknowns and refusals). |
| Measures of Frequency: |
Annual prevalence with 95% confidence interval; and by demographic characteristics when feasible. |
| Time Period of Case Definition: |
Current. |
| Background: |
An estimated 52.5 million adults have doctor-diagnosed arthritis, and 22.7 million report arthritis-attributable activity limitation.1 In 2003 arthritis cost an estimated $128 billion (direct medical and indirect costs).2 Obesity is common among people with arthritis and is a modifiable risk factor associated with arthritis-related disease progression, activity limitation, disability, reduced quality-of-life, total joint replacement, and poor clinical outcomes after joint replacement.3 The prevalence of obesity among adults with arthritis is, on average 54% higher than among adults without arthritis.3 |
| Significance: |
Monitoring the prevalence of arthritis among adults who are obese is important because obesity can worsen arthritis-related joint pain. Reaching and maintaining a normal weight can lower a person’s risk for developing osteoarthritis, the most common type of arthritis representing about 2/3 of arthritis cases, and can improve symptoms and function in people who already have the condition.3 |
| Limitations of Indicator: |
Doctor-diagnosed arthritis is self-reported in the BRFSS and was not confirmed by a health-care provider or objective monitoring; however, such self-reports have been shown to be acceptable for surveillance purposes4 (despite minor changes made in 2011 to the case-finding question to include arthritis on the chronic conditions core). Height and weight are self-reported. Respondents tend to overestimate their height and underestimate their weight,3 likely leading to underestimation of BMI and of the prevalence of obesity. |
| Data Resources: |
Behavioral Risk Factor Surveillance System (BRFSS).
Also, the CDC Arthritis Program typically provides this estimate in standard arthritis BRFSS tables produced for each state for odd numbered years. Unadjusted data are usually presented in these tables to provide actual estimates to help in state-level program planning. |
| Limitations of Data Resources: |
As with all self-reported sample surveys, BRFSS data might be subject to systematic error resulting from noncoverage, nonresponse, or measurement bias. In an effort to address some of these potential concerns, BRFSS began including cell phone only users in the 2011 data collection. Due to changes in sampling and weighting methodology, 2011 is a new baseline for BRFSS, and comparisons with prior year data are inappropriate. |
| Related Indicators or Recommendations: |
Healthy People 2020 Objective AOCBC-7a: Increase the proportion of adults with doctor-diagnosed arthritis who receive health care provider counseling….for weight reduction among overweight and obese persons. |
| Related CDI Topic Area: |
Nutrition, Physical Activity, and Weight Status |