Chronic fatigue syndrome (CFS) describes a condition characterised by severe fatigue of at least six months' duration. In this thesis, it is argued that the complexity of CFS with respect to other symptoms, the patients' response to their illness and the determinants of emotional distress, has yet to be fully recognised. This may have narrowed the focus of research and limited the range of treatments available. The first of the three studies investigated CFS from the patients' perspective. The findings challenge some of the generalisations concerning CFS, particularly those relating to the patients' attributions and their choice of coping strategies. They also suggest that the effects of the condition may have been underestimated and that certain influences on emotional distress may have been overlooked. The second study assessed a number of variables thought to be associated with emotional distress and psychological adjustment. The results show that uncertainty and lack of social support were significantly correlated with anxiety and depression while functional impairment was more closely linked to cognitive difficulties and other illness-related measures. The third study evaluated a management programme which acknowledges the complexity of CFS. After six months, significant differences between the treated patients and waiting-list controls were found for a number of variables, including fatigue, somatic symptoms, anxiety and perceived self-efficacy. However, many patients continued to record high levels of emotional distress, showing that the programme was not sufficient to deal with all the problems experienced.

Purpose The aim of the study was to investigate whether olfactory fluctuations (OF) are pronounced in patients with sinonasal olfactory dysfunction (OD). - Methods The retrospective investigation included patients aged 18 years or older, who consulted a tertiary referral center for olfactory loss. Patients with normal smell function were excluded. Patients answered a structured questionnaire about their olfactory symptoms, with specific questions related to the presence of OF and its average frequency, amplitude, duration, time since most recent OF, and associated symptoms of self-reported OF. Patients also underwent clinical evaluation including a structured medical history and physical examination including nasal endoscopy. In addition, we assessed orthonasal olfactory function using Sniffin’ Sticks, and gustatory function using “taste sprays”. - Results Participants included 131 men and 205 women (n = 336), aged 18 to 86 years (mean 50, SD 16). Patient-reported fluctuations occurred most frequently in sinonasal (38%), idiopathic (29%), and postviral (29%) OD. Amplitude of OF was highest in postviral OD (p = 0.009). Average frequency, duration, and the time since the most recent fluctuation were not significantly different between groups (all p’s > 0.42). Odor discrimination (p = 0.002) and identification (p = 0.017) scores were higher among those individuals with OF. - Conclusion Amplitude of OF may help distinguish postviral from other causes of OD, especially in patients presenting with equivocal symptoms of sinonasal disease.