Impact of environmental factors and physical activity on disability and quality of life in CIDP

Chronic Inflammatory Demyelinating Polyneuropathy and Evaluation of the Visual Evoked Potentials: A Review of the Literature

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare autoimmune disorder characterised by the progressive demyelination of peripheral nerves, resulting in motor and sensory deficits. While much research has focused on clinical and electrophysiological aspects of CIDP, there is an emerging interest in exploring its impact on the visual system through visual evoked potentials (VEPs). This comprehensive review synthesises existing literature on VEP findings in CIDP patients, shedding light on their potential diagnostic and prognostic value. The review thoroughly examines studies spanning the last two decades, exploring VEP abnormalities in CIDP patients. Notably, VEP studies have consistently revealed prolonged latencies and reduced amplitudes in CIDP patients compared to healthy controls. These alterations in VEP parameters suggest that the demyelinating process extends beyond the peripheral nervous system to affect the central nervous system, particularly the optic nerve and its connections. The correlation between VEP abnormalities and clinical manifestations of CIDP, such as visual impairment and sensory deficits, underscores the clinical relevance of VEP assessment in CIDP management. Furthermore, this review addresses the potential utility of VEPs in aiding CIDP diagnosis and monitoring disease progression. VEP abnormalities may serve as valuable biomarkers for disease activity, helping clinicians make timely therapeutic decisions. Moreover, this review discusses the limitations and challenges associated with VEP assessment in CIDP, including variability in recording techniques and the need for standardised protocols. In conclusion, this review highlights the evolving role of VEPs as a non-invasive tool in CIDP evaluation. The consistent VEP abnormalities observed in CIDP patients suggest the involvement of the central nervous system in this demyelinating disorder. As our understanding of CIDP and its pathophysiology continues to evolve, further research in this area may lead to improved diagnostic accuracy and monitoring strategies, ultimately enhancing the clinical management of CIDP patients.

Impact of psychiatric distress and physical disability on quality of life in neuromyelitis optica spectrum disorder and chronic autoimmune demyelinating polyneuropathies

BACKGROUND

Determinants of quality of life (QoL) in demyelinating disorders have been investigated predominantly for multiple sclerosis, especially with regard to "soft clinical signs" such as psychiatric distress. In this exploratory study, we aimed to identify common determinants of QoL for both central and peripheral demyelination in the understudied disease entities of neuromyelitis optica spectrum disorder (NMOSD) and chronic autoimmune demyelinating polyneuropathy (CADP).

METHODS

20 NMOSD and 16 CADP patients were evaluated for physical disability (EDSS and INCAT ODSS), cognitive dysfunction (neuropsychological test battery), psychiatric distress (SCL-90-R), depression (BDI), fatigue (FSMC) and quality of life (EQ-5D-3 L). A linear regression with QoL as a dependent variable and clinical parameters and demographic covariates as independent variables was computed. Additionally, a multivariate analysis of variance was computed to investigate whether NMOSD and CADP differed with regard to QoL and clinical parameters.

RESULTS

Physical disability and psychiatric distress affected QoL in both NMOSD and CADP with a stronger effect for psychiatric distress in comparison to physical disability, as indicated by the higher standardized beta coefficient for psychiatric distress (b = -0.540; p = 0.002 vs. b = -0.614; p = 0.028). NMOSD reported higher subjective well-being than CADP patients (F = 6.845, p = 0.015) while having similar physical disability, cognitive dysfunction, psychiatric distress, depression and fatigue and after having accounted for the influence of age, gender, education and disease duration.

CONCLUSIONS

Our findings suggest that physical disability and psychiatric distress above all clinical factors affect QoL in patients with NMOSD and CADP. Addressing adequately this aspect in demyelinating diseases would contribute to a better QoL in these patients. Furthermore, higher subjective well-being scores for NMOSD than CADP might be attributable to the distinct immunomodulatory therapy regimens and course (relapse-driven vs. chronic) of the two diseases.

Comprehensive approaches for diagnosis, monitoring and treatment of chronic inflammatory demyelinating polyneuropathy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is the most common chronic inflammatory neuropathy. CIDP is diagnosed according to the European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) criteria, which combine clinical features with the electrophysiological evidence of demyelination. However, firstly, diagnosis is challenging, as some patients e.g. with severe early axonal damage do not fulfil the criteria. Secondly, objective and reliable tools to monitor the disease course are lacking. Thirdly, about 25% of CIDP patients do not respond to evidence-based first-line therapy. Recognition of these patients is difficult and treatment beyond first-line therapy is based on observational studies and case series only. Individualized immunomodulatory treatment does not exist due to the lack of understanding of essential aspects of the underlying pathophysiology.

Novel diagnostic imaging techniques and molecular approaches can help to solve these problems but do not find enough implementation. This review gives a comprehensive overview of novel diagnostic techniques and monitoring approaches for CIDP and how these can lead to individualized treatment and better understanding of pathophysiology.