Staying Active With Arthritis: RCT of Physical Activity for Older Adults With Osteoarthritis and Hypertension

Over 9 million Americans have symptomatic osteoarthritis (OA) of the knee, a chronic disease
associated with frequent joint pain, functional limitations, and quadriceps weakness that
intrude upon everyday life. At least half of those with OA of the knee are diagnosed with
hypertension or high blood pressure (HBP), one of the most prevalent risk factors for
cardiovascular disease. Many other individuals with OA of the knee unknowingly have HBP and
remain untreated. Our own work and that of others suggest that persons with OA of the knee
experience reductions in BP when they participate in a regular regimen of physical activity.
Even small decreases in systolic and diastolic BP found with physical activity are clinically
significant, e.g., a 2 mm Hg decrease reduces the risk of stroke by 14% - 17%, and the risk
of coronary heart disease is reduced by 6% - 9%. Yet, only 15% of persons with OA and 47%
with HBP engage in regular physical activity. The purpose of this study is to investigate how
the individually delivered, home-based, 6-month modified Staying Active with Arthritis (STAR)
intervention, guided by self-efficacy theory and modified to address comorbid HBP, affects
lower extremity exercise (flexibility, strengthening, and balance), fitness walking,
functional status, BP, quadriceps strength, pain, fatigue, and health-related quality of life
(HRQoL) in a convenience sample of 224 adults age 50 years or older with OA of the knee and
HBP. Using a randomized controlled, 2-group design, we (1) hypothesize that at the end of the
6-month intervention period and 6 months after the intervention period ends those who receive
the modified STAR intervention will be more likely to perform lower extremity exercise,
participate in fitness walking, show improvements in objective functional status, and
demonstrate reductions in BP than those who receive attention-control. Secondarily, we will
(2) evaluate the impact of the modified STAR intervention, compared to attention-control, on
subjective functional status, quadriceps strength, pain, fatigue, and HRQoL at both time
points; (3) explore the impact of the modified STAR intervention, compared to
attention-control, on self-efficacy and outcome expectancy at both time points; (4) explore
the relationship between self-efficacy and outcome expectancy; and (5) explore the extent to
which self-efficacy and outcome expectancy mediate the relationship between the modified STAR
intervention and performance of lower extremity exercise and participation in fitness
walking. Data will be analyzed using repeated measures modeling.

Inclusion Criteria:

- Age 50 years or older.

- Is community dwelling.

- Has osteoarthritis of the knee.

- Has hypertension for which monotherapy or combination pharmacological treatment is
prescribed.

- Able to complete a behavioral run-in consisting of completing questionnaires, using a
7-day electronic-diary, and wearing an ActiGraph accelerometer at the waist for 7
days.

- Has written permission to participate from the physician.

Exclusion Criteria:

- Reports currently doing lower extremity exercise => 2 times/week.

- Reports currently fitness walking => 90 minutes/week.

- Incapable of managing their own treatment regimen.

- Does not have, or cannot use, a telephone or is unwilling to provide a telephone
number.

- Has received cortisone or Synvisc injections in the knee, angioplasty, stents, or a
pacemaker in the past 6 months.

- Reports unstable cardiovascular, pulmonary, or metabolic disease or signs and symptoms
suggestive of cardiovascular, pulmonary, or metabolic disease that restrict activity.

- Has resting systolic blood pressure => 160 mm Hg or diastolic blood pressure => 100 mm
Hg.

- Reports other conditions, such as osteoarthritis of the hip, spinal stenosis,
inflammatory arthritis, foot drop, diabetes treated with insulin, or diabetic
complications that may affect performance of lower extremity exercise and
participation in fitness walking.

- Reports current knee conditions, such as meniscus tears and knee ligament ruptures.

- Reports major depression that may impact the ability to fully participate in this
study.

- Is scheduled to undergo a major surgical procedure in the next 13 months.

- Is concurrently participating in a drug or psychoeducational trial that may confound,
or be confounded by, participation in this study.