Arthralgia is a common toxicity among women taking aromatase inhibitors (AIs) and can lead to premature discontinuation of therapy. We evaluated the association between arthralgia, co-morbid fatigue/insomnia and inflammatory biomarkers among women taking AIs.
Women taking AIs for early stage breast cancer completed a modified version of the Brief Pain Inventory, the Brief Fatigue Inventory, the Insomnia Severity Index, and provided blood samples for simultaneous assessment of 34 inflammatory biomarkers using a Luminex kit. Two-sided t-tests were used to compare inflammatory biomarker concentrations for patients with or without moderate to severe arthralgia. Multivariate linear regression analyses were performed to evaluate the relationship between comorbid arthralgia, fatigue and insomnia with identified biomarker concentrations.
Among 203 participants, severity of arthralgia, fatigue and insomnia significantly correlated with each other (p < 0.001 for all comparisons). After controlling for race, chemotherapy history, NSAID use, age and BMI, the co-existence of arthralgia, fatigue and insomnia was associated with elevated CRP (β 93.1, 95 % Confidence Interval (CI) [25.1, 161.1], p = 0.008), Eotaxin (β 79.9, 95 % CI [32.5, 127.2], p = 0.001), MCP-1 (β 151.2, 95 % CI [32.7, 269.8], p = 0.013), and VDBP (β 19422, 95 % CI [5500.5, 33344], p = 0.006).
Among women taking AIs, the co-existence of arthralgia, fatigue and insomnia was associated with increased levels of inflammatory biomarkers (elevated CRP, Eotaxin, MCP-1 and VDBP). These findings suggest a possible shared inflammatory mechanism underlying these common symptoms.