Fatigue in Patients with Lung Cancer Is Related with Accelerated Tryptophan Breakdown

BACKGROUND: Patients with cancer often suffer from fatigue and decreased quality of life which might be related to the breakdown of essential amino acid tryptophan. METHODS: In 50 patients with lung cancer we examined fatigue and the deterioration of quality of life in patients using the Functional Assessment of Cancer Therapy Anemia (FACT-An) and -Fatigue (FACT-F) subscales of FACT-General and the Mental adjustment to Cancer (MAC) questionnaires. Results were compared with tryptophan breakdown as well as serum concentrations of immune activation markers. RESULTS: Scores of psychological tests correlated significantly with tryptophan breakdown and with circulatory markers of inflammation. However, immune activation and tryptophan breakdown were not related to MAC scores. CONCLUSIONS: Tryptophan breakdown relates with fatigue and impaired quality of life in patients with lung cancer, while declining tryptophan levels are not associated with patients'coping strategies

Mean concentrations (± SEM) of investigated lab parameters and psychological scores of lung cancer patients with moderate to severe and little or no fatigue, respectively (n.s. = not significant).

<p>Mean concentrations (± SEM) of investigated lab parameters and psychological scores of lung cancer patients with moderate to severe and little or no fatigue, respectively (n.s. = not significant).</p

Spearman rank correlations (two-sided) between investigated parameters of immune activation, haemoglobin levels and fatigue scores as well as patients' self-assessment scores and ECOG scores.

<p>Only p-values ≤0.01 were regarded as significant (after Bonferroni correction for multiple testing). Significant correlations are indicated by asterisks.</p

Baseline characteristics of patients.

<p>Baseline characteristics of patients.</p

Correlations of FACT-AN and FACT-F- scores with tryptophan and hemoglobin concentrations: tryptophan <i>vs.</i> FACT-AN (upper left): rs = 0.409, p<0.01; tryptophan <i>vs.</i> FACT-F (upper right): rs = 0.376, p<0.01; hemoglobin <i>vs.</i> FACT-AN (lower left): rs = 0.426, p<0.01; hemoglobin <i>vs.</i> FACT-F (lower right): rs = 0.400, p<0.01.

<p>Correlations of FACT-AN and FACT-F- scores with tryptophan and hemoglobin concentrations: tryptophan <i>vs.</i> FACT-AN (upper left): rs = 0.409, p<0.01; tryptophan <i>vs.</i> FACT-F (upper right): rs = 0.376, p<0.01; hemoglobin <i>vs.</i> FACT-AN (lower left): rs = 0.426, p<0.01; hemoglobin <i>vs.</i> FACT-F (lower right): rs = 0.400, p<0.01.</p