Natural history of achondroplasia: A retrospective review of longitudinal clinical data

Abstract

There are limited data on the longitudinal frequency and severity of the symptoms and complications of achondroplasia. We undertook a retrospective electronic chart review of 114 patients to develop a more thorough understanding of the lifetime impact of achondroplasia. Craniocervical stenosis (involving the foramen magnum with or without cervical vertebrae C1 and/or C2) was noted in nearly 50% of patients with craniovertebral junction imaging; however, corrective decompression surgery was only needed in 6% of patients. No children in our cohort died at 4 years of age or under. Kyphosis was present in most patients but usually resolved in early childhood. Cervical and lumbar stenosis were diagnosed in children and adults while, genu varum, elbow contractures, and radial head dislocations were identified during childhood. Central sleep apnea and obstructive sleep apnea were present in children, while the diagnosis of obstructive sleep apnea was shown to recur in adulthood. Cardiovascular risk factors were present in only 7% of patients. A range of mental health disorders were identified, with most diagnoses being made before 18 years of age. Our data show that achondroplasia has a significant impact on patients' physical health, and complications continue to be reported and require intervention throughout patients' lifetimes. This highlights the need for continuous support beyond pediatric care, by adult care clinicians experienced with managing the long-term complications of achondroplasia.

Hearing loss in Norwegian adults with achondroplasia

“…The majority of those diagnosed with hearing loss in our study had conductive hearing loss, consistent with prior studies in achondroplasia [ 7 , 11 , 15 ]. Conductive hearing loss is commonly caused by middle ear effusion due to Eustachian tube dysfunction [ 5 , 20 ], as was also reflected by the abnormal tympanometry (Type B or C) and stapedius reflex observed in over 70% of our study participants.…”

“…The present study demonstrated a high prevalence of hearing loss in adults with achondroplasia. Of particular notice was the high prevalence of hearing loss observed in young persons with achondroplasia, consistent with prior studies [ 7 , 9 , 11 ]. These findings highlight the importance of a regular hearing assessment and adequate management and follow-up of acute and chronic middle ear disease during childhood in achondroplasia [ 10 , 12 , 23 ].…”

“…These causes are probably applicable to adults with achondroplasia as well. Impaired hearing might also get less attention in achondroplasia due to the high prevalence of other potential severe medical complications, as well as the daily challenges commonly experienced by persons with this condition [ 10 , 11 , 24 , 35 – 37 ].…”

“…Finally, our study population consisted only of Caucasian participants, although this was not an inclusion criterion. Prevalence rates of hearing loss might be different in achondroplasia populations of other ethnicity, although the medical complication rates, including otitis media infections, seem to be relatively consistent across achondroplasia study populations of different geographical origin [ 9 – 11 , 41 , 42 ].…”

“…In achondroplasia, midface hypoplasia, short Eustachian tubes, small pharynx, and the relative enlargement of tonsils and/or adenoids, are predisposing factors for recurrent upper airway infections and chronic middle ear effusion [3,[6][7][8][9]. Prior studies on children with achondroplasia have reported that up to 70% have experienced acute or recurrent otitis media [9][10][11], giving increased risk of persistent middle ear disease and permanent hearing loss [5,12]. Hearing loss has been reported in 50-70% of children with achondroplasia [6,7,9,13].…”