Impairment of quality of life and cognition in demyelinating neuropathies: targets to be considered from diagnosis to treatment?

Theory of mind and executive dysfunction in chronic inflammatory demyelinating polyneuropathy

BACKGROUND AND PURPOSE

Although chronic inflammatory demyelinating polyneuropathy (CIDP) is understood as a disease affecting the peripheral nervous system, mild cognitive dysfunction, particularly in the executive domain, has been described to form part of the condition. Here our interest lay in CIDP-related theory of mind (ToM) capacities as an aspect of social cognition relevant for many aspects of everyday life.

METHODS

Twenty-nine patients with CIDP and 23 healthy controls participated in this study. They were subjected to overview cognitive testing, different executive function (EF) tasks, as well as to the Faux Pas Recognition Task (FPRT) for assessing cognitive ToM and the Reading the Mind in the Eyes Test (RMET) with respect to affective ToM.

RESULTS

Persons with CIDP and controls did not differ with respect to their overall cognitive state. However, in the German verbal fluency standard, the digit span forward and the digit span backward tests used as EF tasks patients performed significantly worse than controls. Further, performance was abnormally low in the FPRT, whilst the groups did not differ with respect to RMET results. The FPRT and digit span backward results correlated with each other.

CONCLUSIONS

Patients with CIDP showed deficits in cognitive ToM performance together with EF dysfunction, whilst affective ToM was preserved. Altogether, the results suggest that low cognitive ToM capacities in patients with CIDP arise as a particular aspect of disease-related executive dysfunction.

Chronic inflammatory demyelinating polyneurophaty: assessment of the cognitive function and quality of life

BACKGROUND

Studies were carried out with the objective of evaluating the quality of life (QoL) of patients affected by chronic inflammatory demyelinating polyradiculopathy (CIDP). However, the cognitive issue is still little addressed.

OBJECTIVES

To assess the QoL and cognitive impairment of patients with CIDP and to analyze whether there is a correlation between these parameters.

METHODS

Seven patients with CIDP and seven paired controls were subjected to: mini-mental state examination (MMSE); Montreal cognitive assessment (MoCA); digit symbol replacement/symbol copy test (DSST); fatigue severity scale (FSS); Beck depressive inventory-I (BDI-I), and a short-form of health survey (SF-36).

RESULTS

The mean age of the participants was 50 years (71.4% male). The MMSE and MoCA had no statistical difference between the groups. Patients showed superior results in the memory domain in the MoCA (5 vs. 2, p = 0.013). In the DSST, we observed a tendency for patients to be slower. There was a strong negative correlation between fatigue levels and vitality domain (SF-36). There was no significant correlation between depression levels and QoL, and there was no correlation between depression and the results obtained in the cognitive tests. The patients presented higher levels of depression (15.28 vs. 3.42, p < 0.001). A total of 57% had severe fatigue, 28.8% self-reported pain, and 57.1% complained of cramps.

CONCLUSION

There was no cognitive impairment in these patients. However, there was a tendency of slower processing speed. To better evaluate the alterations found, a study with a larger number of individuals would be necessary. Chronic inflammatory demyelinating polyradiculopathy affects the QoL of patients in different ways.