Patients with fibromyalgia frequently complain of cognitive problems or " fibrofog." The existence of these symptoms has been confirmed by studies of the incidence of cognitive problems in fibromyalgia patients and by the results of objective tests of metamemory, working memory, semantic memory, everyday attention, task switching, and selective attention.
The results of these tests show that fibromyalgia patients have impairments in working, episodic, and semantic memory that mimic about 20 years of aging. These patients have particular difficulty with memory when tasks are complex and their attention is divided.
Cognitive symptoms in these patients may be exacerbated by the presence of depression, anxiety, sleep problems, endocrine disturbances, and pain, but the relationship of these factors to cognitive problems in fibromyalgia patients is unclear. Standardized tests and treatment have not yet been established for cognitive problems in fibromyalgia patients. Glass JM: Fibromyalgia and cognition. Journal of Clinical Psychiatry. 69 Suppl 2:20-4, 2008.
Brain areas that are involved in cognition and mood also play a role in pain processing. The goal of this following study was to examine the relationship between chronicpain and cognition [executive functions and memory], while controlling for mood, in cognitively intact older persons and in patients with early stage of probable Alzheimer' s disease who suffered from arthrosis/arthritis.
Painintensity and pain affect were assessed by the Colored Analogue Scale for Pain Intensity and for Pain Affect, the Faces Pain Scale and the Number of Words Chosen-Affective. Level of depression and anxiety were evaluated by questionnaires. Executive functions and memory were assessed by neuropsychological tests.
Cognitively intact older persons showed significant lack of correlations between specific cognitive functions, pain intensity and pain affect. Cognition, in particular memory, appeared to be related to depressive symptoms.
In the patients with Alzheimer' s disease there was a significant positive correlation between executive functions, pain intensity and pain affect measured by the Faces Pain Scale.
Although older persons with depression were excluded, in studies on pain and cognition one should control for the presence of depressive symptoms in older persons with and without dementia. (Scherder EJ, Eggermont L, Plooij B, Oudshoorn J, Vuijk PJ, Pickering G, Lautenbacher S, Achterberg W, Oosterman J: Relationship between chronicpain and cognition in cognitively intact older persons and in patients with Alzheimer' s disease. The need to control for mood.Gerontology. 54(1):50-8, 2008.
Depression is a common feature of chronicpain, but there is only limited research into the content of depressed cognition s in pain patients.This next study investigated the content of cognition in depressed pain patients, non-depressed pain patients, and two control groups, healthy controls, and osteopaths using a sentence completion task.
Participants generated completed sentences to a set of predefined stems that included negative, positive and neutral self-reference, and past, future and world terms.
As predicted depressed pain patients produced more negative sentence completions to all stems than all other groups. Depressed pain patients produced more health related completions than either of the control groups.
Painpatients who were not depressed did not differ from the osteopath control group in the number of health related completions.
It was suggested that the focus of depression in chronicpain patients is health related. Pain patients who are not depressed focus on health, but not necessarily in a negative way. The concept of themselves in the future might be a key aspect in depression in pain patients. (Pincus T, Santos R, Morley S: Depressed cognitions in chronic pain patients are focused on health: evidence from a sentence completion task. Pain. 130(1-2):84-92, 2007).