Increased risk of bullous pemphigoid in dipeptidyl peptidase 4 inhibitors: A nationwide, population-based, cohort study in Taiwan

Targeting type 2 inflammation in bullous pemphigoid: current and emerging therapeutic approaches

Bullous pemphigoid (BP) is one of the most common autoimmune bullous diseases and mainly affects an elderly population with multi-morbidity. Due to the frailty of many BP patients, existing treatment options are limited. The blisters associated with BP result from IgG and IgE autoantibodies binding to the central components of hemidesmosome, BP180, and BP230, stimulating a destructive inflammatory process. The known characteristic features of BP, such as intense pruritus, urticarial prodrome, peripheral eosinophilia, elevated IgE, as well as recent expanding evidence from in vitro and in vivo studies implicate type 2 inflammation as an important driver of BP pathogenesis. Type 2 inflammation is an inflammatory pathway involving a subset of CD4+ T cells that secrete IL-4, IL-5, and IL-13, IgE-secreting B cells, and granulocytes, such as eosinophils, mast cells, and basophils. It is believed that effectors in type 2 inflammation may serve as novel and effective treatment targets for BP. This review focuses on recent understandings of BP pathogenesis with a particular emphasis on the role of type 2 inflammation. We summarize current clinical evidence of using rituximab (B-cell depletion), omalizumab (anti-IgE antibody), and dupilumab (anti-IL-4/13 antibody) in the treatment of BP. The latest advances in emerging targeted therapeutic approaches for BP treatment are also discussed.

Bullous Pemphigoid Associated With Dipeptidyl Peptidase-4 Inhibitors: A Case Report and Review of Current Evidence

Dipeptidyl peptidase-4 inhibitors (DPP-4i), or gliptins, are a widely used glucose-lowering agents. A growing amount of evidence pointed to a possible role of DPP-4i in the induction of bullous pemphigoid (BP), which is an auto-immune skin blistering disease that mainly affects the elderly. In this article we discuss a case of DPP-4i associated BP and we provide an updated review of the current knowledge regarding this emerging entity. Use of DPP-4i, particularly vildagliptin, was found to significantly increase the risk of BP. BP180 would be in the center of the aberrant immune response. DPP-4i induced BP is thought to be associated with male gender, mucosal involvement, and milder inflammatory phenotype especially in Asian population. Generally, patients may not remit fully after DPP-4i withdrawal only and require either topical or systemic glucocorticoid courses.

Dipeptidyl Peptidase-4 Inhibitor-Related Bullous Pemphigoid: Clinical, Laboratory, and Histological Features, and Possible Pathogenesis

Dipeptidyl peptidase-4 inhibitor (DPP4i) is a widely used antidiabetic agent. Emerging cases of DPP4i-associated bullous pemphigoid (DBP), whose pathogenesis remains unclear, have been reported. Thus, a retrospective study was conducted from January 2016 to June 2021 to determine the clinical, laboratory, and histopathological features of DBP and idiopathic bullous pemphigoid (IBP). We set up in vitro experiments using vildagliptin-treated HaCaT keratinocytes to validate what we found by analyzing published RNA sequencing data about the genes related to the dermal-epidermal junction. We also observed IL-6 expression by HaCaT cells treated with vildagliptin. We enrolled 20 patients with DBP and 40 patients with IBP. The total Bullous Pemphigoid Disease Area Index (BPDAI) score was similar in both groups. However, the BPDAI score of erosions and blisters in DBP was significantly higher than that in IBP (24.6 vs. 16.68, p = 0.0189), and the score for urticaria and erythema was lower in DBP (12 vs. 19.05, p = 0.0183). The pathological features showed that the mean infiltrating eosinophil number per high-power field was significantly lower in DBP than in IBP (16.7 vs. 27.08, p = 0.023). The expression of LAMA3, LAMB3, LAMC2, DST, and COL17A1 decreased significantly in vildagliptin-treated human keratinocytes. On the other hand, IL-6, the hallmark cytokine of bullous pemphigoid (BP) severity, was found to be upregulated in HaCaT cells by vildagliptin. These experimental findings imply less of a requirement for eosinophil infiltration to drive the inflammatory cascades in DBP blistering. Both immunologic and non-immunologic pathways could be employed for the development of DBP. Our findings may help explain the higher incidence of non-inflammatory BP that was observed in DBP.

Clinical Phenotypes and the Clinical Course of Bullous Pemphigoid Receiving Dipeptidyl Pepitidase-4 Inhibitor Treatment: An Analysis of Cases in a Single Japanese Center

Objective Several studies have shown an increased risk of bullous pemphigoid (BP) when receiving dipeptidyl pepitidase-4 inhibitor (DPP-4i) treatment. The present study explored the associations of DPP-4i treatment with the clinical phenotypes and clinical course of BP. Methods We analyzed data of 146 patients with BP at Tokai University School of Medicine from December 1, 2009, to December 31, 2021. We obtained data by a retrospective medical record review and compared the bullous pemphigoid disease area index (BPDAI) between diabetes patients receiving DPP-4i treatment and those not receiving DPP-4i treatment. We employed multivariable linear regression models to explore the association between the DPP-4i treatment and the BPDAI scores. Results Among 53 BP patients with diabetes, 33 had developed BP during treatment with DPP-4i agents, among which vildagliptin was the most frequently used. The urticaria/erythema scores of the BPDAI were significantly lower in patients who developed BP while receiving DPP-4i treatment than among others. Of note, 69.2% of the patients who stopped DPP-4i treatment experienced complete remission, and the clinical course was more favorable in patients with lower scores for urticaria/erythema than among others. Conclusion These findings suggest that, in patients who developed BP while receiving DPP-4i treatment, a noninflammatory phenotype may indicate a high likelihood that DPP-4i treatment contributes to the development of BP. The discontinuation of DPP-4i should be carefully considered in close consultation with dermatologists.

Tai Chi Program to Improve Glucose Control and Quality of Life for the Elderly With Type 2 Diabetes: A Meta-analysis

OBJECTIVE

To systematically evaluate the effects of Tai chi for improving elderly patients with type 2 diabetes.

METHODS

According to PRISMA checklist, we conducted this standard meta-analysis. The multiple databases like Pubmed, Embase, and Cochrane databases were used to search for the relevant studies, and full-text articles involved in the evaluation of Tai chi in improving elderly patients with type 2 diabetes. Review manager 5.2 was adopted to estimate the effects of the results among selected articles. Forest plots, sensitivity analysis and funnel plot for the articles included were also conducted.

RESULTS

Finally, 7 relevant studies were eventually satisfied the included criteria. We found that Tai chi group had lower glucose than control group (mean difference (MD)=-12.47, 95%CI [-21.20, -3.73], P=.005; I2 = 32%), Tai chi group had higher activities-specific balance confidence (ABC) scale than control group (MD =9.26 with 95%CI [6.68, 11.83], P < .001) and Tai chi group had higher single limb standing test score than control group (MD = 8.38, 95%CI [4.02, 12.74], P = .001). The study was robust and limited publication bias was observed in this study.

CONCLUSION

Since we found Tai chi had better performance than usual care in improving old diabetes patients' glucose and life quality, the study supports that Tai chi can help old diabetes patients from several aspects including disease indicators, independence and life quality.

Dipeptidyl peptidase-4 inhibitor-induced autoimmune diseases: Current evidence

Dipeptidyl peptidase-4 inhibitors (DPP-4i) have an important place in the management of type 2 diabetes. The DPP-4 enzyme is ubiquitously distributed throughout the human body and has multiple substrates through which it regulates several important physiological functions. DPP-4 regulates several immune functions, including T-cell activation, macrophage function, and secretion of cytokines. Studies have reported an increase in autoimmune diseases like bullous pemphigoid, inflammatory bowel disease, and arthritis with DPP-4i use. The relationship of DPP-4i and autoimmune diseases is a complex one and warrants further research into the effect of DPP-4 inhibition on the immune system to understand the pathogenesis more clearly. Whether a particular cluster of autoimmune diseases is associated with DPP-4i use remains an important contentious issue. Nevertheless, a heightened awareness from the clinicians is required to identify and treat any such diseases. Through this review, we explore the clinical and pathophysiological characteristics of this association in light of recent evidence.

Efficacy / safety balance of DPP-4 inhibitors versus SGLT2 inhibitors in elderly patients with type 2 diabetes

Dipeptidyl peptidase-4 inhibitors (DPP-4is) and sodium-glucose cotransporter type 2 inhibitors (SGLT2is) offer new options for the oral management of type 2 diabetes mellitus (T2DM), with the advantage in the elderly population to be devoid of a high risk of hypoglycaemia. SGLT2is have also shown benefits regarding cardiovascular (heart failure) and renal protection, including in patients with T2DM aged ≥ 65 years while DPP-4is have only proved cardiovascular and renal safety without superiority compared with placebo. The glucose-lowering efficacy of the two pharmacological classes is almost similar including in older patients with T2DM. However, the tolerance and safety profile may be highly different and overall more favourable with DPP-4is than with SGLT2is. Some adverse events have been reported with SGLT2is which may be more prevalent or severe in older patients than in younger patients. The present comprehensive review focuses on the benefit/risk balance in the elderly population with T2DM by comparing the profile of DPP-4is and SGLT2is regarding the following potential issues: metabolic disorders (hypoglycaemia and diabetic ketoacidosis); cardiac and vascular issues (atheromatous cardiovascular disease, heart failure, volume reduction hypotension, and lower limb amputations); renal endpoints including acute renal injury; risk of infections; digestive disorders; bone and skin adverse events; and cancer risk. Both DPP-4is and SGLT2is have their own advantages and disadvantages. Personalised treatment is recommended based upon the efficacy/safety profile of each drug class and individual patient characteristics that may be markedly different among the heterogeneous population of older individuals with T2DM.

Defining dipeptidyl peptidase-4 inhibitors-related bullous pemphigoid: A single-centre retrospective study

BACKGROUND

Many studies have corroborated the association of dipeptidyl peptidase-4 inhibitors (DPP4i) use with bullous pemphigoid (BP). It has been speculated that this drug-induced variant presents with a different clinical spectrum than conventional BP.

OBJECTIVE

To determine the prevalence of DPP4i-induced cases of BP and to evaluate whether gliptin-related BP has specific clinicopathological and immunological features.

METHODS

We conducted a retrospective, observational study of BP cases attended at our centre between January 2000 and June 2020. Epidemiological, clinical, histopathological and laboratory data were collected.

RESULTS

A total of 257 cases of BP were collected; 51 (24.3%) were on treatment with DPP4i. When analysing DPP4i-induced BP cases, generalized BP was the predominant pattern and scalp/mucosal involvement was found in 13 patients. Gliptin-related BP cases were associated to a decrease in the eosinophilic infiltrate (p = 0.000) and both the detection rate and concentration of anti-BP180 IgG were lower (p = 0.004, p = 0.001, respectively) than non-DPP4i cases.

LIMITATIONS

Retrospective, single-centre study.

CONCLUSION

Our large DPP4i-induced BP case series has highlighted that DPP4i-induced BP is characterized by generalized lesions and scalp involvement. Lower titres of anti-BP180 antibodies and a decrease in eosinophils infiltrating into the skin may be distinct features of DPP4i-related BP.

The association of bullous pemphigoid with dipeptidyl-peptidase 4 inhibitors: a ten-year prospective observational study

BACKGROUND

Bullous pemphigoid is the most common bullous chronic autoimmune skin disease. Recent studies have suggested dipeptidyl-peptidase 4 inhibitors as possible predisposing agents of bullous pemphigoid. The objective of our study was to prospectively estimate the association between gliptins and the development of bullous pemphigoid.

METHODS

We conducted a prospective study which included all patients diagnosed with biopsy-proven bullous pemphigoid in the Dermatology Department of our hospital between April 1, 2009 and December 31,2019. The diagnosis of bullous pemphigoid was based on specific clinical, histological and immunological features.

RESULTS

Overall 113 consecutive patients (age 75 ± 13 years, 62 females) with the diagnosis of bullous pemphigoid were enrolled. Seventy-six patients (67.3%) suffered from type 2 Diabetes and 52 (46%) were treated with dipeptidyl-peptidase 4 inhibitors. The most frequent prescribed gliptin was vildagliptin, being administered to 45 cases (39.8% of total patients enrolled, 86.5% of the patients treated with gliptins). Gliptins were withdrawn immediately after the diagnosis of bullous pemphigoid, which together with steroid administration led to remission of the rash.

CONCLUSIONS

This study revealed that treatment with dipeptidyl-peptidase 4 inhibitors, especially vildagliptin, is significantly associated with an increased risk of bullous pemphigoid development.

Dipeptidyl peptidase-4 inhibitor-related bullous pemphigoid: A comparative study of 100 patients with bullous pemphigoid and diabetes mellitus

Dipeptidyl peptidase-4 inhibitor (DPP4i)-associated bullous pemphigoid (BP) has been emerging but whether it has genotype or phenotype differences from idiopathic BP (IBP) remains to be determined. We aimed to compare clinical characteristics, genetic susceptibility, laboratory features, disease activity, and outcomes between DPP4i-associated BP (DBP) and IBP occurring among patients with diabetes mellitus type 2 (T2DM). Medical records of patients diagnosed with BP and T2DM from January 2009 to December 2019 were retrospectively reviewed, and patients were categorized into DBP or IBP groups. Of 100 patients, 23 had DBP and 77 had IBP. There was no difference in the Bullous Pemphigoid Disease Activity Index score between the two groups; however, the score for urticaria and erythema was less in DBP (p < 0.001), indicating a non-inflammatory phenotype. The HLA-DQB1*03:01 allele was more commonly present in the DBP than IBP cases (odds ratio = 5.33 [95% confidence interval, 1.11-28.59], p = 0.016). The absolute eosinophil count was significantly lower in the DBP group (p = 0.002). Likewise, eosinophilic spongiosis was found less frequently in DBP cases (p = 0.005). Patients in the DBP group had a significantly higher percentage of complete remission on therapy compared to the IBP counterpart (p = 0.026) after DPP4i discontinuation. Moreover, the mean maximum dosage of prednisolone administrated per patient was significantly lower in drug-related cases (p = 0.012). In conclusion, our cohort in Thai patients with T2DM confirms the differences between phenotype and genotype characteristics of DBP and IBP. We emphasize the importance of drug discontinuation in all DPP4i-related cases because doing so may lead to a better disease outcome.

Tolerability, safety, pharmacokinetics and pharmacodynamics of SHR0534, a potent G protein-coupled receptor 40 (GPR40) agonist, at single- and multiple-ascending oral doses in healthy Chinese subjects

SHR0534 is being developed for type-2 diabetes mellitus. Herein the tolerability, safety, pharmacokinetics and pharmacodynamics of SHR0534 in healthy Chinese subjects were assessed in a phase-I, randomized, double-blind, placebo-controlled, single- and multiple-ascending dose study. Forty subjects were randomized 4:1 to receive SHR0534 at the dose of 10, 25, 50 or 100 mg, or placebo, and another eleven subjects were allocated to either the 5 mg group or the placebo group at an 8:3 ratio. All subjects received a single dose on day 1, followed by a 9-day washout and once-daily administrations for 14 consecutive days. Serial samples were collected, and vital signs, electrocardiograms, laboratory tests, urinalysis and adverse events (AEs) were recorded. All doses of SHR0534 were safe and well tolerated with infrequent, generally mild-to-moderate AEs and no serious AEs in the study. SHR0534 was absorbed with a T _max of approximately 4 hours, and systemic exposure increased with dose. Accumulation was minimal (2- to 3-fold) and steady state was reached after seven days of dosing. For pharmacodynamics, no significant hypoglycaemic effects were seen in healthy adults. Good pharmacokinetics and safety were demonstrated but no obvious effect was found.

Clinical Features and Outcomes of Dipeptidyl Peptidase-4 Inhibitor-Associated Bullous Pemphigoid (DPP4i-Associated BP) in Thai Patients

The use of dipeptidyl peptidase-4 inhibitors (DPP4i) appears to be associated with a small but significantly elevated risk of bullous pemphigoid (BP). Although the pathogenic mechanism of DPP4i-associated BP remains unclear, this adverse event is reported with multiple gliptins, suggesting a class effect. However, previous studies from various countries showed that vildagliptin had been implicated in most cases. The aim of this study was to illustrate a case series of DPP4i-associated BP in Thai patients. We conducted a retrospective study from consecutive cases of BP in people with type 2 diabetes mellitus (T2DM) from January 2008, the year in which the first DPP4i was introduced in Thailand, until December 2019. During the study period, 10 BP patients with T2DM were identified. A total of 5 DPP4i-associated BP (3 on vildagliptin, 1 on linagliptin, and 1 on sitagliptin) were found. All patients were male with a mean age at BP development of 80.4 years (73–86 years). All patients had a long-standing duration of diabetes (median duration 34 years), and mean A1C was 7.5 ± 1.4%. The median time to BP development after the introduction of DPP4i was 64 months (range 20–128 months). The severity of BP was classified as mild in 2 cases. In all cases, the association between the drug intake and BP onset was classified as “possible” according to the Naranjo causality scale. All of the patients continued taking DPP4i after BP diagnosis, and one patient died of lung cancer 18 months after BP diagnosis. Only 2 patients could achieve complete remission at least 2 months after stopping DPP4i. Our case series demonstrated a potential link between DPP4i and the development of BP, which mainly occurred in very elderly male patients. The latency period from an introduction of DPP-4i could be several years, and the clinical course after DPP4i discontinuation varied. Clinicians prescribing DPP4i should be aware of this association and consider stopping this medication before a refractory disease course ensues.

Bullous Pemphigoid: Trigger and Predisposing Factors

Bullous pemphigoid (BP) is the most frequent autoimmune subepidermal blistering disease provoked by autoantibodies directed against two hemidesmosomal proteins: BP180 and BP230. Its pathogenesis depends on the interaction between predisposing factors, such as human leukocyte antigen (HLA) genes, comorbidities, aging, and trigger factors. Several trigger factors, such as drugs, thermal or electrical burns, surgical procedures, trauma, ultraviolet irradiation, radiotherapy, chemical preparations, transplants, and infections may induce or exacerbate BP disease. Identification of predisposing and trigger factors can increase the understanding of BP pathogenesis. Furthermore, an accurate anamnesis focused on the recognition of a possible trigger factor can improve prognosis by promptly removing it.

Association Between Medication Use and Bullous Pemphigoid: A Systematic Review and Meta-analysis

Importance

The association between the use of medications and the development of bullous pemphigoid (BP) is unclear.

Objective

To assess the associations between previous exposure to certain medications and BP.

Data Sources

For this systematic review and meta-analysis, PubMed, the Cochrane Central Register of Controlled Trials, and Embase were searched for relevant studies from inception to February 20, 2020.

Study Selection

Case-control or cohort studies and randomized clinical trials that examined the odds or risk of BP in patients with previous medication use were included. No geographic or language limitations were imposed.

Data Extraction and Synthesis

The Meta-analysis of Observational Studies in Epidemiology (MOOSE) guideline was followed. The Newcastle-Ottawa Scale was used to evaluate the risk of bias of included observational studies; Cochrane Collaboration's tool was used for randomized clinical trials. Aggregate data were used to conduct a random-effects model meta-analysis if the included studies were sufficiently homogenous. Subgroup analyses were performed for use of various medications of the same category.

Main Outcomes and Measures

Odds ratio (OR), hazard ratio, and risk ratio of bullous pemphigoid in association with medication use.

Results

This meta-analysis included 13 case-control studies, 1 cohort study, and 1 randomized clinical trial with a total of 285 884 participants. The meta-analysis of case-control studies showed a significant association of BP with previous use of aldosterone antagonists (pooled OR, 1.75; 95% CI, 1.28-2.40), dipeptidyl peptidase 4 inhibitors (pooled OR, 1.92; 95% CI, 1.55-2.38), anticholinergics (pooled OR, 3.12; 95% CI, 1.54-6.33), and dopaminergic medications (pooled OR, 2.03; 95% CI, 1.34-3.05). One cohort study found an increased risk of BP among patients receiving dipeptidyl peptidase 4 inhibitors (hazard ratio, 2.38; 95% CI, 1.16-4.88; P = .02). One trial found a higher occurrence of BP in patients with diabetes receiving linagliptin (0.2% in diabetes group vs 0% in the placebo group).

Conclusions and Relevance

The findings of this systematic review and meta-analysis suggest that aldosterone antagonists, dipeptidyl peptidase 4 inhibitors, anticholinergics, and dopaminergic medications are associated with BP. These medications should be judiciously prescribed, particularly in high-risk patients who are elderly and have disabling neurologic disorders.