Congenital laryngomalacia is related to exercise-induced laryngeal obstruction in adolescence

Abstract

Objectives: Congenital laryngomalacia (CLM) is the major cause of stridor in infants. Most cases are expected to resolve before 2 years of age, but long-term respiratory prospects are poorly described. We aimed to investigate if CLM was associated with altered laryngeal structure or function in later life.

Methods: Twenty of 23 (87%) infants hospitalised at Haukeland University Hospital during 1990-2000 for CLM without comorbidities and matched controls were assessed at mean age 13 years. Past and current respiratory morbidity was recorded in a questionnaire, and spirometry performed according to standard quality criteria. Laryngoscopy was performed at rest and continuously throughout a maximal treadmill exercise test (continuous laryngoscopy exercise test (CLE-test)), and scored and classified in a blinded fashion according to preset criteria.

Results: In the CLM group, laryngeal anatomy supporting CLM in infancy was described at rest in nine (45%) adolescents. Eleven (55%) reported breathing difficulties in relation to exercise, of whom 7 had similarities to CLM at rest and 10 had supraglottic obstruction during CLE-test. Overall, 6/20 had symptoms during exercise and similarities to CLM at rest and obstruction during CLE-test. In the control group, one adolescent reported breathing difficulty during exercise and two had laryngeal obstruction during CLE-test. The two groups differed significantly from each other regarding laryngoscopy scores, obtained at rest and during exercise (p=0.001 or less).

Conclusions: CLM had left footprints that increased the risk of later exercise-induced symptoms and laryngeal obstruction. The findings underline the heterogeneity of childhood respiratory disease and the importance of considering early life factors.

Keywords: Congenital laryngomalacia; Exercise induced inspiratory symptoms; Follow-up study; Respiratory Disorders; Vocal cord dysfunction.

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Figures

Figure 1

The score system (Maat score) used to describe findings during continuous laryngoscopy exercise test (CLE-test). *The scores at each level (glottic (A and C) and supraglottic (B and D)) were assessed at moderate (A and B) (when subject started to run) and at maximal effort (C and D) (just before the subject stopped running at the treadmill); all four numbers (A–D) were noted together with a sum score (E) for each test/subject (Adapted from Eur Arch Othorhinolaryngol30).

Figure 2

Scores of laryngeal movements obtained during a continuous laryngoscopy exercise test (CLE-test) in 20 adolescents hospitalised for congenital laryngomalacia (CLM) and 20 healthy control subjects with no such history. The left graph (Maat-D) depicts scores for supraglottic movements during maximal exercise. The right graph (Maat-E) depicts a total score from the CLE-test. The boxes show IQRs, with bold lines denoting medians. Vertical bars denote minimum and maximum scores.

Figure 3

Venn diagrams depicting occurrence of self-reported dyspnoea during exercise, and laryngeal findings at rest and during exercise. Findings, exercise: Maat-D score of 2 or 3 at maximum exercise during the continuous laryngoscopy exercise test (CLE-test). Findings, rest: Prominent arytaenoids and epiglottis at rest. Symptoms: Self-reported dyspnoea during exercise. The areas of the circles are proportional to the number of subjects (n) with the condition in question. Overlapping areas indicate subjects with two or three findings.