The relationship between motor neuron disease and bullous pemphigoid: An English cohort study

Neurological and psychiatric associations in bullous pemphigoid-more than skin deep?

In elderly patients, bullous pemphigoid (BP) is associated with several comorbidities; the strongest association occurs between BP and neurological diseases. Different types of dementia, Parkinson's disease, cerebrovascular disorders and epilepsy all have a significant association with BP, but patients with multiple sclerosis have the highest risk of BP. An existing neurological disorder appears to increase the risk for subsequent BP, but an increased risk for developing some neurological diseases has also been reported following BP diagnosis. BP seems to be associated with several psychiatric diseases such as schizophrenia, uni- and bipolar disorder, schizotypal and delusional disorders, and personality disorders, but the risk ratios are usually lower than with neurological diseases. In addition to the skin, the BP autoantigens BP180 and BP230 are expressed in the central nervous system. This finding together with the strong epidemiological association between neurological disorders and BP has led to an assumption that neurodegeneration or neuroinflammation could lead to a cross-reactive immunoresponse between neural and cutaneous antigens and the failure of self-tolerance. A subpopulation of patients with Alzheimer's disease or Parkinson's disease have circulating IgG autoantibodies against BP180, but currently their significance for the development of BP is unclear, because these antineural BP180 antibodies neither bind to the cutaneous basement membrane nor cause BP-like symptoms. Further studies analysing large and well-characterized populations of neurological and psychiatric patients are required to understand better the role of autoimmunization against neural BP autoantigens in the pathogenesis of BP.

Increased Levels of the Bullous Pemphigoid BP180 Autoantibody Are Associated with More Severe Dementia in Alzheimer's Disease

Bullous pemphigoid (BP) is a subepidermal blistering skin disease, which has shown a strong association with neurological diseases in epidemiological studies. The BP autoantigens BP180 and BP230 are expressed in the cutaneous basement membrane and the central nervous system. Using BP180 and BP230 ELISA assays and immunoblotting against BP180, we analyzed the IgG reactivity in the sera of 115 patients with Alzheimer's disease (AD) and 40 neurologically healthy controls. BP180 autoantibodies were found in 18% of patients with AD, whereas only 3% of controls had positive results (P = 0.019). BP230 values were higher and more often elevated in patients with AD than controls, but not significantly. None of the positive AD sera that recognized the full-length human BP180 in immunoblotting reacted with the cutaneous basement membrane in indirect immunofluorescence analysis. Moreover, a retrospective evaluation of the hospital records of the patients with AD revealed neither BP diagnosis nor BP-like symptoms. Interestingly, increased BP180-NC16A autoantibody values correlated with cognitive decline measured by mini-mental state examination scores, but not with the concentration of AD biomarkers in cerebrospinal fluid. Our findings further the understanding of the role of BP180 as a shared autoantigen in neurodermatological interactions and the association between BP and neurodegenerative diseases.

Psychiatric and neurological disorders are associated with bullous pemphigoid - a nationwide Finnish Care Register study

Bullous pemphigoid (BP) is an autoimmune blistering skin disease with increasing incidence. BP is associated with neurological disorders, but it has not been established, what subtypes of dementia and stroke are associated with BP, and what is the temporal relation between these diseases. Also, the association between BP and psychiatric disorders is controversial. We conducted a retrospective nationwide study, using the Finnish Care Register for Health Care diagnoses between 1987 and 2013. The study population of 4524 BP patients were compared with 66138 patients with basocellular carcinoma (BCC), neurological and psychiatric comorbid disorders were evaluated for both groups, and associations were estimated by Cox regression and logistic regression analyses. The strongest risk of developing BP was found after diagnosis of multiple sclerosis (MS) (OR=5.9, 95% CI 3.9–8.5). Among psychiatric diseases, the corresponding risk was strongest in schizophrenia (OR=2.7, 95% CI 2.0–3.5), and as a novel finding, also personality disorders (OR=2.2, 95% CI 1.3–3.3) preceded BP. In conclusion, many psychiatric disorders, especially schizophrenia, carry heightened risk for BP. Furthermore, several neurological diseases which cause central nervous system inflammation or degeneration were related to BP, and the association was strongest between MS and BP.

A population-based study of the association between bullous pemphigoid and neurologic disorders

BACKGROUND

Bullous pemphigoid (BP) has been associated with neurologic disorders.

OBJECTIVE

We sought to analyze the association between BP and neurologic disorders.

METHODS

We retrospectively identified residents of Olmsted County, Minnesota, with a first lifetime diagnosis of BP between January 1, 1960, and December 31, 2009. Three age- and sex-matched Olmsted County, Minnesota, residents without BP were selected as control subjects for each patient. We compared history of or development of neurologic disorders (dementia, Alzheimer disease, Parkinson disease, multiple sclerosis, cerebrovascular disease, and seizures) between groups using case-control and cohort designs.

RESULTS

In all, 87 patients with BP were identified and matched to 261 control subjects. The odds of a previous diagnosis of any neurologic disorder or a history of dementia were significantly increased among cases compared with controls (odds ratio 6.85; 95% confidence interval [CI] 3.00-15.64; P < .001; and odds ratio 6.75; 95% CI 2.08-21.92; P = .002, respectively). Both Parkinson disease (hazard ratio 8.56; 95% CI 1.55-47.25; P = .01) and any type of neurologic disorder (hazard ratio 2.02; 95% CI 1.17-3.49; P = .01) were significantly more likely to develop during follow-up in patients with than without BP.

LIMITATIONS

Small geographic area and retrospective study design are limitations.

CONCLUSION

Findings confirmed an association of BP with neurologic disorders, especially dementia and Parkinson disease.