SCD Pain Impact Associated With Social, Emotional Functioning

The pain impact of sickle cell disease (SCD) was associated with emotional and social functioning among patients in a study published in The Journal of Pain. This association was found to be stronger than those between previously researched biological modifiers and pain impact.

SCD is a red blood cell disorder that affects about 100,000 people in the United States alone. Pain is a noted adverse event for those who are diagnosed with SCD, affecting both quality of life and health care costs. Research into pain among patients with SCD has mostly focused on biological variables, whereas little is known about pain-specific variables in SCD.

The study aimed to “use multivariable modeling to examine the strength of associations of psychosocial and biological variables with pain impact, an SCD-specific measure of pain interference.”

The GRNDaD research registry, which aims to collect data on patients with SCD, was used to source data for this study. Researchers assessed patient-reported outcomes, labs, and other clinical data. Participants were included in the study if they had a diagnosis of SCD, were aged 8 years and older, and had completed at least 1 pain or pain-related patient-reported outcome by April 2022.

The pain-specific variables that were studied included pain locations, pain variability, and frequency of SCD pain episodes. Social and emotional functioning were assessed using data from 2 Adult Sickle Cell Quality of Life Measurement Information System pain subscales: Social Functioning Impact Measure and Emotional Impact Measure. All raw scores were converted to T-scores.

There were 723 participants who completed at least 1 pain-related survey, and 203 participants completed all 3 questionnaires. A total of 60% of participants were female, and the participants had a median (IQR) age of 34 (26-42) years; 67% had sickle-cell anemia, whereas 21% had sickle hemoglobin C disease or sickle beta-thalassemia disease (7.1%).

At the time of enrollment, 64% of the sample reported experiencing chronic pain. Overall, 44% of participants reported having 4 or more pain episodes related to SCD in the previous 12 months. The median impact score was 51 (44-64) in the sample, and the median Patient-Reported Outcomes Measurement Information System physical function score was 43 (38-49).

"Relative importance of each predictor variable to the model was derived from the Wald chi-square analysis of variance of the full model compared to the model without the potential predictor, subtracting the degrees of freedom used by the predictor," the authors explained.

The multivariable regression model found that social functioning (Wald X², 87.47; P < .001), emotional functioning (Wald X², 57.86; P < .001), income (Wald X², 20; P < .001), age (Wald X², 15.60; P = .004), and number of pain episodes related to SCD (Wald X², 13.98; P = .007) were all associated with pain impact. Lower pain impact was found in individuals with better social and emotional functioning, with changes in pain impact coming at T-scores of 45 to 60.

Changes in pain impact were also found to be most pronounced from ages 20 to early 30s, with pain increasing steadily in late adolescence and young adulthood before decreasing slightly from early to mid-thirties.

There were some limitations to this study. Causality could not be established due to the cross-sectional design of the study. The study was also limited to a single registry for its data, which was also self-reported and can be subject to recall bias. The patient-reported outcome surveys have not been established for pediatric patients diagnosed with SCD. Variations in funding, resources, and availability of treatments need to be considered when interpreting the findings.

This study can help “establish the causal role of psychosocial variables in adverse pain outcomes in SCD,” the authors concluded. Pain-specific psychological variables should be studied in the future to compare with biological modifiers when it comes to pain impact and severity.

Reference

Kenney MO, Wilson S, Shah N, et al. Biopsychosocial factors associated with pain and pain-related outcomes in adults and children with sickle cell disease: a multivariable analysis of the GRNDaD multi-center registry. J Pain. Published online August 4, 2023. doi:10.1016/j.jpain.2023.07.029