Factors Affecting Dilation Interval in Patients With Granulomatosis With Polyangiitis-Associated Subglottic and Glottic Stenosis

Abstract

Objective: Subglottic stenosis (SGS) is a known complication of granulomatosis with polyangiitis (GPA). We investigated the impact of medical and surgical interventions on the surgical dilation interval and characterized patients with glottic involvement.

Study design: A retrospective chart review of patients with GPA-associated SGS was performed from 2010 to 2019.

Setting: Tertiary academic medical center.

Methods: The impact of medical and surgical interventions on dilation interval was assessed. The prevalence of glottic involvement was assessed, and clinical characteristics and outcomes were compared with patients without glottic involvement.

Results: A total of 39 patients with GPA-associated SGS were analyzed. Dilation intervals in patients receiving leflunomide (n = 4; median, 484 days; 95% CI, 405-1099) were greater than in those not receiving leflunomide (median, 155 days; 95% CI, 48-305; P = .033). The surgical technique used did not affect dilation interval. Patients with glottic involvement (n = 13) had a greater incidence of dysphonia (13/13 vs 15/26 [58%], P = .007) and a shorter dilation interval with involvement (median, 91 days; interquartile range, 70-277) versus without involvement (median, 377 days; interquartile range, 175-1148; hazard ratio, 3.38; 95% CI, 2.26-5.05; P < .001). Of 13 patients, 8 (62%) did not have glottic involvement on first presentation.

Conclusion: Although GPA is classically thought to affect the subglottis, it also involves the glottis in a subset of patients. These patients have greater complaints of dysphonia and require more frequent surgery. Systemic therapy may increase dilation intervals. In this preliminary study, patients taking leflunomide demonstrated an improvement, highlighting the need for further study of immunosuppression regimens in the treatment of GPA-associated SGS.

Keywords: dysphonia; glottic stenosis; granulomatosis with polyangiitis; laryngotracheal stenosis; subglottic stenosis; vasculitis.

Figure 1.

Predicted time to next dilation by glottic involvement: median, 91 days with glottic involvement (IQR, 70–277) vs 377 days without (IQR, 175–1148). Cox hazard ratio, 3.38; 95% CI, 2.26–5.05; P<.001. IQR, interquartile range.

Figure 2.

Distribution of dilation intervals in patients receiving and not receiving leflunomide. Box plots (median, interquartile range, range) and accompanying line plots (No.) are shown.

Figure 3.

Distribution of dilation intervals in patients receiving and not receiving rituximab. Box plots (median, interquartile range, range) and accompanying line plots (No.) are shown. Dotted lines indicate patients who did not receive the medication until after their last dilation procedure.

Figure 4.

Distribution of dilation intervals in patients receiving and not receiving methotrexate. Box plots (median, interquartile range, range) and accompanying line plots (No.) are shown.

Figure 5.

Distribution of dilation intervals in patients receiving and not receiving azathioprine. Box plots (median, interquartile range, range) and accompanying line plots (No.) are shown.

Figure 6.

Distribution of dilation intervals in patients receiving immunosuppressive monotherapy compared to multiple immunosuppressants. Box plots (median, interquartile range, range) and accompanying line plots (No.) are shown. AZA, azathioprine; MTX, methotrexate.