Using Surveys to Assess Patient-Centered Factors that May Affect Responses to Chronic Pain Treatment

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What was the research about?

Patients’ beliefs and expectations may affect how they respond to treatment. But these feelings are hard to measure.

In this study, the research team created a set of surveys called Healing Encounters and Attitudes Lists, or HEAL. HEAL helps researchers understand patients’ beliefs and expectations about treatment. HEAL measures patients’

• Connections with their doctors and nurses
• Feelings about their doctor’s office and staff
• Expectations about treatment
• Outlook on life
• Strength of spiritual beliefs
• Comfort with complementary or alternative medicine, or CAM

The team also used the Patient-Reported Outcomes Measurement Information System, or PROMIS®, to measure patients’ pain, health, and function. PROMIS is a set of surveys researchers and doctors use for many diseases and treatments.

The team wanted to learn if HEAL could predict how patients respond to treatment for chronic pain. Chronic pain is pain that lasts for months or years. The team used HEAL and PROMIS to look at why some groups of patients respond differently to treatment for chronic pain. Patients got either conventional treatment, such as physical therapy or medicine, or CAM, such as acupuncture, chiropractic treatment, or massage.

What were the results?

Using HEAL to predict how patients respond to treatment

• The more positive a patient’s HEAL scores, the greater symptom improvement they reported after two and four months.
• Some HEAL scores seemed to predict pain intensity after two and four months. In addition, some HEAL scores seemed to predict how much pain affected patients’ life activities. But then the research team looked at how intense patients’ pain was and how much pain affected patients’ activities at the start of the study. Once the team accounted for these factors, the ability of HEAL scores to predict pain intensity and its effect on activities was much less clear.

Understanding why patients respond differently to treatment

• Patients with higher expectations for treatment had less pain and better health and function after two and four months compared with patients with lower expectations for treatment.
• Compared with patients who chose CAM, those who chose conventional treatment had more pain and worse health and function after two and four months. But compared with those who chose CAM, patients who chose conventional treatment also had more pain and worse health at the start of the study.

Who was in the study?

The study included 209 patients with chronic pain. Patients’ pain must have lasted for at least three months. Of patients, 76 percent were white, 23 percent were non-white or multiracial, and 7 percent were Hispanic. The average patient age was 48, and 75 percent were women. Of the 209 patients, 109 received CAM and 100 received conventional treatment.

What did the research team do?

Patients filled out HEAL and PROMIS surveys within a month of starting treatment and again two and four months later. The research team looked to see if HEAL scores predicted patients’ symptom improvement and pain as reported on PROMIS surveys. In addition, the team looked at how patients’ expectations for treatment, measured by HEAL, and the type of treatment they chose affected their pain, health, and function after treatment, as measured by PROMIS.

During the study, the team met with a group of patients, patient advocates, and clinicians. This group gave input on research questions, study design, and ways to share results.

What were the limits of the study?

The study included only people with chronic pain. Results may not apply to people with other health problems. The research team didn’t look at all possible reasons why patients responded differently to treatment.

Future research could see if using HEAL and PROMIS in doctors’ offices and hospitals helps patients talk about treatments with their doctors.

How can people use the results?

HEAL and PROMIS may help researchers understand what factors affect patients’ responses to chronic pain treatment.

Objective

(1) To assess whether factors assessed by Healing Encounters and Attitudes Lists (HEAL) predict pain treatment outcomes in patients receiving complementary or alternative medicine (CAM) treatment or conventional medicine treatment; (2) To assess heterogeneity of treatment effects using the Patient-Reported Outcomes Measurement Information System (PROMIS^®) and HEAL

Study Design

To measure how patient beliefs or treatment expectations may affect health outcomes, researchers developed HEAL, a set of item banks that measure patient-provider connection; healthcare environment perceptions; treatment expectancy, or patient expectations about whether the treatment will be helpful; positive outlook; spirituality; and attitudes toward CAM. Researchers also used PROMIS, a set of item banks measuring patient function, symptoms, behaviors, and feelings standardized to be comparable across various populations.

The study included 209 patients with chronic pain who completed HEAL and PROMIS measures online at baseline, or within one month of starting treatment, and then again two and four months later. The average age was 48, and 75% of patients were female. Of the patients, 76% were white, 23% were non-white and multiracial, and 7% were Hispanic.

For objective 1, at two and four months, researchers examined the relationship between baseline HEAL scores and patient-reported clinical global improvement and between baseline HEAL scores and PROMIS pain intensity and pain interference scores.

For objective 2, researchers assessed heterogeneity of treatment effects first based on type of treatment chosen by the patients (CAM versus conventional treatments) and second based on the patients’ baseline HEAL treatment expectancy scores (higher versus lower treatment expectations). The team modeled separately the five pain and health outcomes using treatment type and HEAL treatment expectancy score as predictors, with and without controlling for baseline status for each pain treatment outcome, and examined longitudinal differences.

A group of patients, patient advocates, and clinicians gave input on research questions, study design, and dissemination of results.

Results

Predicting pain treatment outcomes using HEAL baseline measures. All baseline HEAL measures except spirituality were positively correlated with clinical global improvement at two and four months; correlations ranged from 0.16 to 0.26 (p<0.05). Several baseline HEAL measures were correlated with two- and four-month pain outcomes; absolute correlations ranged from 0.16 to 0.31 (p<0.05). However, after controlling for baseline pain level, researchers found that HEAL measures accounted for little variance in outcomes: from 1.5% to 3.7% across analyses.

Assessing heterogeneity of treatment effects. Treatment type and HEAL treatment expectancy score were predictors of the five pain and health outcome measures. After adjusting for control variables, researchers found that patients receiving conventional treatments generally had worse pain, overall health, and physical function at two and four months than patients receiving CAM treatments. Patients with lower baseline treatment expectancy scores also had worse pain, health, and function than patients with higher baseline treatment expectancy scores.

Limitations

The study included only patients with chronic pain, limiting generalizability to other populations. To assess heterogeneity of treatment effects, the study evaluated only treatment type and HEAL treatment expectancy scores; the role of other factors remains unknown. Further, patients self-selected into each clinical arm, and the conventional medical treatment group entered the study with higher pain levels and poorer health. These group differences could have affected the observed outcomes.

Conclusions and Relevance

Factors such as patient beliefs or treatment expectations, as assessed by the HEAL measures, may be important contributors to clinical global improvement and pain treatment outcomes. Having a more positive treatment expectation and choosing CAM versus conventional medical treatment were associated with better outcomes over four months of follow-up.

Future Research Needs

Future research could evaluate HEAL and PROMIS measures in populations with other conditions or assess the feasibility of implementing the measures in real-world clinical settings. Researchers could use HEAL measures in large trials to test whether treatment beliefs and personal characteristics influence the placebo effect.