Comorbidities of bullous pemphigoid: A single-center retrospective case-control study from Turkey

Accurate diagnosis of bullous pemphigoid requires multiple health care visits

Introduction

Accurate use of diagnostic codes is crucial for epidemiological and genetic research based on electronic health record (EHR) data.

Methods

This retrospective study validated the International Classification of Diseases (ICD)-10 diagnostic code L12.0 for bullous pemphigoid (BP) using EHR data from two Finnish university hospitals. We found 1225 subjects with at least one EHR entry of L12.0 between 2009 and 2019. BP diagnosis was based on clinical findings characteristic of BP and positive findings on direct immunofluorescence (DIF), BP180-NC16A enzyme-linked immunosorbent assay (ELISA) or indirect immunofluorescence (IIF) assay.

Results

True BP was found in 901 patients; the positive predictive value (PPV) for L12.0 was 73.6% (95% CI 71.0-76.0). L12.0 was more accurately registered in dermatology units than any specialized health care units (p<0.001). Including patients with multiple L12.0 registrations (≥3), increased the accuracy of the L12.0 code in both dermatology units and other settings.

Discussion

One diagnostic code of L12.0 is not enough to recognize BP in a large epidemiological data set; including only L12.0 registered in dermatology units and excluding cases with <3 L12.0 record entries markedly increases the PPV of BP diagnosis.

Comorbidity in bullous pemphigoid: up-date and clinical implications

Bullous pemphigoid is the most common autoimmune blistering disease in industrialized countries and particularly affects the elderly. In this patient population, comorbid diseases are frequent and may complicate management and treatment of bullous pemphigoid. A better understanding why distinct diseases are more frequent in bullous pemphigoid patients may lead to new pathophysiological insights and - as a consequence - result in better patient care. The association of bullous pemphigoid with neurological and psychiatric diseases is well known and confirmed by several case-control studies. Association with further diseases such as malignancy and metabolic diseases are still discussed controversially. In recent years new relationships between bullous pemphigoid and autoimmune as well as inflammatory skin diseases have been reported. This review provides a systematic overview on studies addressing comorbidity in bullous pemphigoid patients. Increasing the awareness of both, common and rare comorbid diseases, may enable clinicians to optimize patient support and individualized treatment of bullous pemphigoid.

Brain MRI findings in patients with bullous pemphigoid: A case-control study

Evidence suggests that bullous pemphigoid (BP) is associated with multiple neurological disorders. We aimed to compare brain magnetic resonance (MRI) findings between BP patients and a control group. This case-control study included patients with BP referred to two dermatology clinics during a two-year period. A group of individuals attending the same clinics for cosmetic procedures were selected as controls. First, participants' general information including age, gender, education, weight and underlying disease was recorded. For BP patients, the drugs and the BP Disease Area Index (BPDAI) were recorded as well. Then, all participants underwent brain MRI without contrast. The Fazekas scale, the general cerebral atrophy (GCA) score, and the Medial Temporal lobe Atrophy (MTA) score were used to assess MRI images. Overall, 24 BP patients and 24 controls were evaluated in this study. Both groups were comparable regarding age, gender and education. However, diabetes and hypertension were more frequent in the control group. The mean BPDAI total score was 51.39 ± 68.92 in BP patients and most of them used rituximab (41.7%). None of the participants had MS or Alzheimer MRI patterns. There was no difference between groups in terms of GCA and MTA scores. Furthermore, the frequency of partially empty sella did not differ significantly between BP patients and controls (p = 0.461); nevertheless, grade-3 Fazekas was significantly higher in BP patients compared to controls (25% vs. 0%, p = 0.019). Of note, one BP patient had an epidermoid cyst and another had moderate enlargement of three ventricles. Also, new infarcts were observed in two and old infarcts in four BP patients. Although the majority of abnormal brain MRI findings were more frequent in BP patients compared to controls, only grade-3 Fazekas was significantly higher and acute infarcts were exclusively observed in BP patients.

The association between Parkinson's disease and autoimmune diseases: A systematic review and meta-analysis

Parkinson's disease (PD) is a neurodegenerative disorder that frequently occurs in the older population. Previous epidemiological studies have suggested an association between PD and autoimmune diseases (AIDs). However, some studies have shown conflicting results. This study aimed to summarize existing epidemiological studies on the association between PD with AIDs and to conduct a meta-analysis of combinable results. Four electronic databases (PubMed, Embase, Web of Science Core Collection, and MEDLINE) were searched from each database's inception date until December 12, 2022. All studies that explored the relationship between PD and AIDs were included for quantitative analysis and qualitative review. The pooled relative risk with 95% confidence intervals (CIs) was calculated using a random or fixed effects model. A total of 46 observational studies involving 873,643 patients and 13,402,821 controls were included; ultimately, 38 studies were included in the meta-analysis. The risk of PD combined with AIDs was significantly higher (odds ratio [OR]=1.55, 95% CI: 1.33-1.81), and subgroup analysis found no significant differences in risk by study type, gender, age, and race. Regarding the AID types, the results showed an increased risk of PD combined with bullous pemphigoid (OR=2.67, 95% CI: 2.15-3.31), inflammatory bowel disease (OR=1.30, 95% CI: 1.18-1.45), Crohn's disease (OR=1.30, 95% CI: 1.20-1.42), ulcerative colitis (OR=1.31, 95% CI: 1.14-1.50), Sjögren's syndrome (OR=1.61, 95% CI: 1.24-2.09), and Graves' disease (OR=1.45, 95% CI: 1.24-1.70) than controls. However, there appeared to be no significant association between PD and systemic lupus erythematosus (OR=0.82, 95% CI: 0.66-1.03), multiple sclerosis (OR=2.02, 95% CI: 0.87-4.70), rheumatoid arthritis (OR=0.79, 95% CI: 0.61-1.03), or celiac disease (OR=1.16, 95% CI: 0.79-1.69). This study supports the existence of a strong link between AIDs and PD. When PD and AIDs are identified, clinicians need to be aware of the possibility of coexistence. However, there are some limitations of this study, such as the apparent heterogeneity of some of the results and the fact that most of the included study types were retrospective. Therefore, future larger prospective cohort studies are needed to further explore the interaction between PD and AIDs.

Systematic review registration

INPLASY, identifier INPLASY202280088.

Relationship between bullous pemphigoid and metabolic syndrome: a 12-year case-control study conducted in China

Background

Hypertension, diabetes, dyslipidemia, and obesity are prevalent in patients with bullous pemphigoid (BP) and are all components of metabolic syndrome (MS). However, the prevalence of MS in patients with BP is unknown. We aimed to evaluate the relationship between MS and BP and to define the clinical and laboratory characteristics of patients with both conditions.

Methods

This retrospective case-control study was conducted for 12 years at Peking Union Medical College (162 with BP and 162 age and sex-matched controls). The components of MS were analyzed and logistic regression was used to identify independent risk factors for BP. In addition, the clinical and laboratory characteristics of patients with BP ± MS were compared.

Results

The prevalence of MS in patients with BP was 35.2% and that in controls was 14.8% (p < 0.001). After adjustment for sex and age, multivariate analysis demonstrated a positive correlation between BP and MS [odds ratio (OR) 2.490, 95% confidence interval (CI) 1.040-5.963], diabetes (OR 1.870, 95% CI 1.029-3.396), and overweight or obesity (OR 1.807, 95% CI 1.026-3.182). In the BP group, participants with MS were older (p = 0.006), were less likely to present erythema (p = 0.028), and had higher serum C3 (p = 0.007) and incidence of infection within 1 year of their diagnosis (p = 0.035) than participants without MS.

Conclusion

MS and its components hyperglycemia and overweight were found to be independently associated with BP. Therefore, clinicians should screen for MS in patients with BP, especially if they are older, present less erythema, or have a high serum C3.