Research published in Cancer revealed that inflammatory responses may be tied to cancer-related fatigue and certain inflammatory activities may lead to distinct dimensions of fatigue in women with early-stage breast cancer.
“Our findings indicate that inflammation plays a role in some aspects of cancer-related fatigue, but not others, and that these effects persist well after treatment,” said lead study author Julienne E. Bower, PhD, Professor, UCLA Departments of Psychology and Psychiatry/Biobehavioral Sciences; Associate Director, Cousins Center for Psychoneuroimmunology, Semel Institute for Neuroscience and Human Behavior; and Member, Jonsson Comprehensive Cancer Center. “This is critical for developing targeted treatments for this common and disabling symptom.”
Rationale and Study Methods
Although inflammatory activity resulting from tumors and/or cancer treatment are considered to be a driver of cancer-related fatigue, full inflammatory activity and its relationship with fatigue has not been thoroughly explored previously.
The researchers analyzed protein markers of inflammation in 192 women with early-stage breast cancer. Each patient completed assessments before and after adjuvant therapy as well as at 6, 12, and 18 months after treatment to provide indicators of their dimensions of fatigue—general, physical, mental, and emotional. Inflammatory markers focused on TNF-α, sTNF-RII, IL-6, and CRP.
Associations between inflammatory markers and dimensions of fatigue were considered for both within each person and between persons.
Key Study Findings
Positive within-person associations were found between general fatigue and levels of TNF-α (b = 1.67; P = .037), sTNF-RII (b = 2.77; P = .002), and IL-6 (b = 0.86; P = .010) when analysis adjusted for age, race, education, body mass index, and cancer stage. Positive within-person associations were also found between physical fatigue and TNF-α (b = 1.58; P = .007), sTNF-RII (b = 2.38; P < .001), and CRP (b = 0.43; P = .007). Negative within-person associations were observed between emotional fatigue and TNF-α (b = –1.92; P = .004) and sTNF-RII (b = –2.10; P = .006). Positive between-person associations were found between general (b = 0.82; P = .024) and physical fatigue and CRP (b = 0.71; P = .012).
No significant associations were found linking mental fatigue and inflammatory markers.
These findings “highlighted individual variability in inflammatory markers as a key predictor of fatigue symptoms,” the study authors concluded.
Disclosure: For full disclosures of the study authors, visit acsjournals.onlinelibrary.wiley.com.
