Which symptoms come first? Exploration of temporal relationships between cancer-related symptoms over an 18-month period

Abstract

Background: Anxiety, depression, insomnia, fatigue, and pain are frequently reported by cancer patients. These symptoms are highly interrelated. However, few prospective studies have documented the sequence with which symptoms occur during cancer care. Purpose: This longitudinal study explored the temporal relationships between anxiety, depression, insomnia, fatigue, and pain over an 18-month period in a large population-based sample of nonmetastatic cancer patients (N = 828), using structural equation modeling. Methods: The patients completed a battery of self-report scales at baseline and 2, 6, 10, 14, and 18 months later. Results: The relationships between the same symptom at two consecutive assessments showed the highest coefficients (β = 0.29 to 0.78; all ps ≤ 0.05). Cross-loading parameters (β = 0.06 to 0.19; ps ≤ 0.05) revealed that fatigue frequently predicted subsequent depression, insomnia, and pain, whereas anxiety predicted insomnia. Conclusions: Fatigue and anxiety appear to constitute important risk factors of other cancer-related symptoms and should be managed appropriately early during the cancer care trajectory. © 2012 The Society of Behavioral Medicine.