Exercise Maintenance in Chronic Pain and PTSD

This study will compare the effects of a 3-month, individually prescribed progressive
exercise training program on: 1) chronic low back pain (cLBP), depression and PTSD symptoms,
and 2) neurobiological and related neuropsychological mechanisms by which our
exercise-training paradigm may foster exercise maintenance. More specifically, the
investigators hypothesize relationships between exercise-training associated augmentation of
neuropeptide Y (NPY) system function and improved capacities for reward and
self-regulation—neuropsychological capacities posited to underlie intrinsic motivation and
self-efficacy, which in turn have been shown to predict exercise maintenance. This study will
focus on Veterans with cLBP/PTSD. The study design includes a baseline, acute,
cardiopulmonary exercise assessment (CPX) that will inform the exercise prescription for the
12-week "progressive exercise" training program, comprised of three 30-45 minute in clinic
exercise sessions per week (walking or running--depending on the ability/capacity of the
participant). All exercise sessions will be supervised by an exercise physiologist in the
Clinical Studies Unit (CSU) at VA Boston Healthcare System. Intermittent telephone calls by
the researchers will provide additional motivational support and problem solving.
Implementation of the prescribed exercise regimen will also be supported by the use of heart
rate and actigraph monitors programmed for the participant to achieve their prescribed heart
rate range (HRR). Also, a "midpoint" and "endpoint" CPX assessment will track changes in NPY
system function and delineate their impact on pain, depression and PTSD symptoms, as well as
the factors proposed to foster exercise maintenance. All three CPX tests will be performed in
accordance with guidelines published by the American College of Cardiology. Among Veterans
with cLBP/PTSD, the investigators hypothesize that the capacity to release NPY in response to
vigorous exercise (i.e., acute CPX testing) will be associated with improvements in pain,
depression and PTSD symptoms, as well as the putative factors that predict exercise
maintenance. Data from this R21 will be used to demonstrate feasibility and inform the
further development of individually prescribed, motivationally based exercise regimens that
could be used as adjuncts to cognitive and other therapeutic PTSD, depression or chronic pain
interventions to reduce cLBP, depression and PTSD, as well as the negative consequences of
these disorders over the long-term.

Inclusion Criteria:

1. ICD-9 or ICD-10 diagnosis of chronic low back pain, as confirmed by the rehabilitation
medicine doctor consulting to the study, and a confirmed comorbid psychiatric
diagnosis of PTSD. More specifically, the CLBP/PTSD participant must meet for current
chronic PTSD (>3 months) as assessed by the CAPS-5, 1-Month Diagnostic Version.

2. A medical history, physical examination, vital signs, EKG, and baseline laboratory
studies, including urine toxicology screens and a negative urine pregnancy test (woman
only), indicate that symptom-limited cardiopulmonary exercise stress (CPX) testing
will be safe.

3. Women of child bearing capacity must agree to use effective contraception while
participating; a urine pregnancy test performed on the morning prior to completing CPX
testing will also be done.

4. Relatively sedentary at enrollment, as defined by the American College of Sports
Medicine (i.e., performing less than 30 minutes/day and less than 150 minutes per week
of moderate physical activity).

5. Free of medications and other substances (e.g., illicit drugs and alcohol) with
effects that could hinder data interpretation for 2-6 weeks before the cold pressor
test (CPT) and CPX testing depending on the medication and frequency of use (which
must be cleared by the study Co-I and study MD, Dr. Rasmusson).

6. Psychotropic medications are allowed, as long as the participant has been stable on
them for two months.

7. Tobacco product use is allowed; participants will not be required to lower or stop
their dosage/intake; intensity of smoking will be monitored across the study via use
of urine testing for cotinine (a long-lived metabolite of nicotine) at each test
session. Regular morning nicotine users will be instructed to smoke/chew to
satisfaction just prior to arriving at the Clinical Studies Unit for testing, which
will be approximately 2-3 hours prior to performance of the CPT and CPX.

8. Using pain medications other than opiates provided none taken for 5 half-lives before
CPT/CPX testing, generally about 24 hours.

9. Other anxiety or depressive disorders are permitted

10. May be involved in supportive psychotherapies as long as their participation has been
stable for 3 months prior to study entry and remains stable throughout the course of
the study

11. Can have a mild to moderate TBI, as determined by the BAT-L assessment.

12. Taking medications for chronic psychiatric or medical illnesses is allowed as long as
the medications and medication dosing are stable for two months prior to participation
in the study and remain stable throughout the 12 week exercise training protocol and
final exercise test.

Exclusion Criteria:

1. A life threatening or acute physical illness (e.g., cancer), current schizophreniform
illnesses, bipolar disorder, or active suicidal or homicidal ideation requiring
clinical intervention.

2. Current or past alcohol and/or substance dependence (less than three months from date
of screening assessment)

3. Current opiate pain medication use

4. Women who are or are planning to become pregnant within the next six months

5. Individuals seeking pain treatment such as surgical interventions or who have a
neuropathic origin to their pain

6. Cannot tolerate exercising on a treadmill or on an upright bike due to chronic pain

7. A clinical history of coronary artery disease or positive stress test, uncontrolled
cardiac arrhythmia, moderate-to-severe aortic stenosis, severe arterial hypertension
(systolic >200 mmHg, diastolic>110 mm Hg) and more than first degree atrioventricular
block

8. Severe TBI, as evidenced on the VA TBI screen and the BAT-L assessment.