5 Questions About Osteoarthritis and Mortality Risk

Osteoarthritis (OA) is a diverse condition with multiple variables affecting manifestation and prognosis. Previous research on the association between OA and increased mortality has not been clear and small sample sizes only resulted in limited generalizability.

In a population-based cohort study, JuYoung Park, MSW, PhD, associate professor at the Phyllis and Harvey Sandler School of Social Work at Florida Atlantic University, and colleagues evaluated data of 51,938 adults from National Health and Nutrition Examination Surveys followed for up to 20 years, to examine the differences in mortality risk associated with OA. The study cohort also included 2589 participants with diagnosed radiographic knee OA.

Rheumatology Consultant caught up with Dr Park about the research.

Rheumatology Consultant: Your study is the first to evaluate differences in risk of mortality associated with OA while considering participant characteristics such as age, gender, ethnicity, body mass index, physical activity, and smoking. What are the key findings from your study?

JuYoung Park: While self-reported OA was not associated with mortality, knee OA was associated with higher incidence of cardiovascular disease, diabetes, and renal mortality, especially in individuals with early onset of disease or with obesity. However, knee OA was associated with reduced risk of cancer mortality. Those who were diagnosed with knee OA prior to aged 40 years and obese patients had a worse prognosis.

RHEUM CON: Results from your study found no association between mortality and self-reported OA in the study participants. Were you surprised by this?

JP: I was surprised that there was no significant association between self-reported OA and mortality in the nationally representative populations. However, this does not mean that those with self-reported OA do not need to receive OA treatment. Those with self-reported OA tended to be older, women, non-Hispanic White, to have a lower socioeconomic status, to be overweight, and to be nonsmokers. These are more vulnerable populations and still must manage symptoms and risk factors for OA. 

Clinical takeaways, next steps >>

RHEUM CON: What can a rheumatologist take away from the results of your study and apply to clinical practice?

JP: Since knee OA was associated with higher cardiovascular disease, diabetes, and renal mortality, especially in individuals with early onset of disease or with obesity, rheumatologists should pay close attention to patients with knee OA with comorbidities of cardiovascular disease, diabetes, or renal mortality. The first step for the rheumatologist is to start conversations with OA patients who also have one of those diseases regarding the risk of mortality. It is important for the rheumatologist to take a compassionate, nonstigmatizing approach, as studies have also found that clinician empathy increases patients’ motivation to visit specialists and to change lifestyle, especially in terms of exercise and diet. The rheumatologist should refer such patients to a specialist who can consult with the primary physician about treating cardiovascular disease, diabetes, or renal disease, regardless of how well the patient has managed OA symptoms. The patient should learn how to manage the disease to prevent risk of early death. In addition, the rheumatologist should order x-ray tests on knees of patients who are at risk for OA. Once patients are diagnosed with knee OA, the patients should carefully manage not only symptoms of OA but symptoms of other potentially associated conditions.

RHEUM CON: The risk for developing OA is between 24-40% and individuals with obesity are at increased risk. How do you think a rheumatologist can approach managing a patient’s OA caused by obesity and other lifestyle factors?

JP: The rheumatologist can explain that obesity places an individual at greater risk of developing arthritis in the first place and then point out that those who have been diagnosed with radiographic knee OA prior to aged 40 years have a worse prognosis. The challenge will be convincing patients with obesity and OA, or those who are at risk of developing OA, to lose weight and change their lifestyle.

RHEUM CON: What are the next steps in your research?

JP: This study was the first to examine mortality in OA based on age of onset of OA and obesity. For the next step in our research, we will identify safe and effective nonpharmacological interventions, as well as pharmacological treatment, for persons with knee OA to manage symptoms, including pain, in order to decrease the risk of mortality from cardiovascular disease, diabetes, or kidney diseases, and to improve the overall health-related quality of life.

References:

1. Mendy A, Park J, Ramos Vieira E. Osteoarthritis and risk of mortality in the USA: a population-based cohort study. Int J Epidemiol. 2018;47(6):1821-1829. doi:10.1093/ije/dyy187.

For more OA content, visit the Resource Center.