Grutsch et al. BMC Cancer 2011, 11:193 http://www.biomedcentral.com/1471-2407/11/193 Table 5 Statistically Significant (P < 0.05) Correlations between Quality of Life (QoL) Domains and Cosinor Parameters in Outpatients QoL Domains Mesor Amplitude Circadian Quotient Rhythm Quotient 24-hr Correlation Night-day Sleep Balance EORTC Symptom Items Fatigue Pain Loss of Appetite EORTC Functional Domains Social Role Cognitive EORTC Global Health item Ferrans-Powers QLI Domains Health/Function Social/Economic Psychological Spiritual Family 0.44 0.51 0.38 .45 0.45 -0.4 0.39 -0.41 -0.39 .34 0.4 0.53 0.45 Page 9 of 13 -0.52 -0.47 0.56 0.45 0.39 0.40 0.45 than population-based control data. Our patients took many prolonged daytime naps, while suffering many epi- sodes of prolonged awakening for prolonged spans dur- ing each night. Similar findings have been reported for patients early stage breast cancer and metastatic color- ectal cancer [52,53]. These patients also reported quality of life outcomes that were significantly lower than popu- lation based controls. Our patients’ responses to the EORTC instrument reveal they were experiencing multi- ple symptoms and their capacity to meet the challenges of routine life was compromised. Our patients, like others with advanced cancer, were very dissatisfied with their health. Every patient self report for the QLI health/functioning domain fell within the bottom quar- tile as compared to the general population scores, indi- cating a uniformly high level of dissatisfaction with their physical health. On the other hand, their scores for the other three QLI domains, social/economic, family, and psychological/spiritual were indistinguishable from those of the general population. Our patients were emotionally and psychologically healthy, despite lethal cancer asso- ciated ill health. This finding illustrates the resilience of the human spirit, even in the face of lethal symptomatic disease and the value of asking questions relevant to the whole life of the cancer patient. An interesting finding was the lack of a significant relationship between a self-reported insomnia among outpatients and any objectively measured actigraphy parameter. This finding is surprising considering that actigraphy data showed that virtually every patient’s sleep was fragmented and unconsolidated and these patients’ self reports of their sleep quality, as measured by a validated sleep questionnaire, was indistinguish- able from insomniacs [49,50]. This non sequitor between universal objective signs of very poor sleep and the perception of insomnia among advanced lung cancer is interesting. It seems as though, in cancer patients as in the healthy elderly, the perception of nocturnal sleeplessness and the reality of it are at odds. Inpatients did report an association between an actigraphy parameter and insomnia. We can speculate that hospital routines involve a sudden increase in number of untoward nighttime awakenings that results in the patients feeling much sleepier than they did in the prior week. Similar findings have been reported for patients with metastatic colorectal cancer [52]. Two- thirds of the patients for whom it was measured suf- fered from mild, moderate or severe chronic COPD. There were no statistically significant relationships between the degree of dyspnea and any parameter of circadian function. These findings indicate that both lung cancer and COPD are associated with shortness of breath but that quality of life decrement is only associated with cancer symptoms and circadian disrup- tion and not COPD severity, which is usually relatively stable and chronic.