A history of asthma is associated with susceptibility to hidradenitis suppurativa: a population-based longitudinal study.

The association of hidradenitis suppurativa (HS) and asthma remains to be investigated. To assess the bidirectional association between HS and asthma. A population-based study was conducted to compare HS patients (n = 6779) with age-, sex-, and ethnicity-matched control subjects (n = 33,259) with regard to the incidence of new onset and the prevalence of preexisting asthma. Adjusted hazard ratios (HRs) and adjusted odds ratios (ORs) were calculated. The prevalence of preexisting asthma was higher in patients with HS relative to controls (9.6% vs. 6.9%, respectively; P < 0.001). The odds of HS were 1.4-fold greater in patients with a history of asthma (fully adjusted OR 1.41; 95% CI 1.27-1.55; P < 0.001). The incidence rate of new-onset asthma was estimated at 9.0 (95% CI 6.3-12.7) and 6.2 (95% CI 5.1-7.5) cases per 10,000 person-years among patients with HS and controls, respectively. The risk of asthma was not statistically different in patients with HS and controls (fully adjusted HR 1.53; 95% CI 0.98-2.38; P = 0.062). Relative to other patients with HS, those with HS and comorbid asthma were younger at the onset of HS (30.7 [14.7] vs. 33.3 [15.1], respectively; P < 0.001) and had a comparable risk of all-cause mortality (adjusted HR 0.86; 95% CI 0.44-1.68; P = 0.660). A history of asthma confers susceptibility to subsequent development of HS. This observation is of importance for clinicians managing both patients with HS and asthma. Further research is warranted to elucidate the pathomechanism underlying this finding.

Vitiligo and Crohn's disease form an autoimmune cluster: insights from a population-based study.

BACKGROUND: While the coexistence of vitiligo and Crohn's disease (CD) has been reported in individual patients, the epidemiological association between these autoimmune conditions remains inconclusive. OBJECTIVE: To assess the bidirectional association between vitiligo and CD. METHODS: A population-based study was performed to compare vitiligo patients (n = 20,851) with age-, sex- and ethnicity-matched control subjects (n = 102,475) regarding the incidence of new-onset and the prevalence of preexisting CD. Adjusted hazard ratios (HRs) and adjusted odds ratios (ORs) were calculated by multivariable Cox regression and logistic regression, respectively. RESULTS: The incidence rate of new-onset CD was evaluated at 3.6 (95% CI, 2.7-4.9) cases per 10,000 person-years (PY) in patients with vitiligo and 2.4 (95% CI, 2.0-2.9) cases per 10,000 PY in controls. Patients with vitiligo experienced an elevated risk of CD (fully adjusted HR, 1.60; 95% CI, 1.10-2.34; p = 0.015). Congruently, a history of preexisting CD predicted elevated odds of having subsequent vitiligo (fully adjusted OR, 1.49; 95% CI, 1.15-1.93; p = 0.002). Compared to other patients with vitiligo, those with vitiligo and comorbid CD were older and had a higher prevalence of diabetes mellitus, hyperlipidemia, and hypertension but a comparable all-cause mortality rate. CONCLUSIONS: The current study depicts a robust bidirectional association between vitiligo and CD. This knowledge is of clinical implication for physicians managing patients with both conditions. The diagnostic threshold for CD should be lowered in vitiligo patients with compatible symptoms.

Mortality in Patients with Bullous Pemphigoid: A Retrospective Cohort Study, Systematic Review and Meta-analysis.

There is little consensus regarding mortality data in bullous pemphigoid (BP). The aim of this study was to evaluate mortality among a relatively large cohort of Israeli patients with BP and to perform a meta-analysis synthesizing existing data on 1-year mortality rates of patients with BP. This retrospective cohort study of 287 patients diagnosed with BP between 2000 and 2015 compared the mortality of patients with BP with age- and sex-matched control subjects in the general population. The results showed 1-, 5- and 10-year mortality rates of 26.9%, 56.9% and 69.5%, respectively, and a 3.4-fold higher risk of death. A systematic review and meta-analysis were then performed using a random effects model. Including the current study, 25 studies comprising 4,594 patients met the eligibility criteria. The pooled estimate of 1-year mortality rate was 23.5% (95% confidence interval 20.2-26.8; I2=81%; p < 0.001). The pooled 1-year mortality rate of European cohorts was prominently higher relative to the pooled rates of cohorts from the USA and Asia.

Mean Platelet Volume in Pemphigus Vulgaris.

Pemphigus vulgaris (PV) is an autoimmune blistering disease of the skin and mucous membranes. The mean platelet volume (MPV) is an index of platelet activation reported to be influenced by inflammation. We investigated the MPV in patients with PV relative to controls. This case-control study included 160 patients with PV and 640 age- and sex-matched controls. The MPV, platelet count, and other inflammatory parameters were measured for all study participants. A significantly decreased MPV was observed in patients with PV compared with controls, 9.1 (1.5) fL versus 10.3 (1.4) fL, P < .001. A significant negative association between MPV and PV was demonstrated in multivariate analysis (odds ratio, 0.59; 95% confidence interval, 0.51-0.68, P < .0001). Patients having PV with laryngeal involvement had significantly lower MPVs than those without involvement of the larynx, 8.81 (1.5) fL versus 9.32 (1.4) fL, P = .032. Disease activity (before and after treatment) does not affect the MPV. Patients with PV showed decreased MPV values compared to healthy controls. The MPV may be a feasible diagnostic marker in patients with PV.