Acquired childhood glaucoma is more prevalent than congenital types of glaucoma, according to the results of a population-based study reported in the April issue of the Archives of Ophthalmology.
"Childhood glaucoma is an uncommon pediatric condition often associated with significant visual loss," write Elisabeth P. Aponte, MD, from the Mayo Clinic in Rochester, Minnesota, and colleagues. "It consists of a heterogeneous group of diseases leading to optic neuropathy and visual field changes that can be categorized into primary, secondary, and acquired subtypes. Primary glaucoma in children is generally divided into primary congenital glaucoma (from birth to early childhood) and juvenile primary open-angle glaucoma (4 years to early adulthood)."
Secondary glaucoma in children is present at birth but is related to other medical conditions or syndromes (eg, aniridia, Axenfeld-Rieger syndrome, retinopathy of prematurity, Rubinstein-Taybi syndrome, Sturge-Weber syndrome, and persistent hyperplastic primary vitreous and congenital rubella). Acquired childhood glaucoma, often classified as secondary glaucoma, is caused by other processes not present at birth, such as trauma, surgery, inflammation, or medications.
The study goal was to determine the incidence and clinical characteristics of childhood glaucoma in a defined US population by reviewing the medical records of all pediatric patients younger than 20 years living in Olmstead County, Minnesota, from January 1, 1965, through December 31, 2004, and meeting diagnostic criteria for glaucoma or suspicion of glaucoma.
During the 40-year study period, 30 children were diagnosed with glaucoma, with incidence of 2.29 (95% confidence interval [CI], 1.47 - 3.12) per 100,000 residents younger than 20 years. Of the 30 cases, 19 were acquired (1.46/100,000; 95% CI, 0.80 - 2.12), 6 were secondary (0.45/100,000; 95% CI, 0.08 - 0.82), and 5 were primary glaucoma (0.38/100,000; 95% CI, 0.05 - 0.72).
Also during the 40-year time period, the birth prevalence of primary congenital glaucoma was 1 per 68,254 residents younger than 20 years, or 1.46 per 100,000 (95% CI, 0.03 - 8.16). There were also 24 individuals identified with suspicion of glaucoma, yielding an incidence of 1.9 per 100,000 residents younger than 20 years (95% CI, 1.14 - 2.66).
"The incidence of childhood glaucoma in this population was 2.29 per 100 000 residents younger than 20 years or 1 per 43 575 residents younger than 20 years," the study authors write. "Acquired and secondary forms of glaucoma were the most common, whereas congenital and juvenile glaucoma were rare."
Limitations of this study include retrospective design leading to nonstandardized and incomplete data collection; pressure measurements performed by different examiners; the possibility of missing certain forms of asymptomatic glaucoma, resulting in underestimated incidence; limited generalizability due to the homogeneity of the population;, and low incidence of childhood glaucoma in this population.
"This study provides population-based incidence rates for childhood glaucoma diagnosed during a 40-year period," the study authors conclude. "The most common type of glaucoma was acquired glaucoma (traumatic, surgical, uveitic or drug-induced), accounting for 63 percent of patients with glaucoma, whereas the secondary and primary forms were less common."
An unrestricted grant from Research to Prevent Blindness Inc supported this study. The study authors have disclosed no relevant financial relationships.
Arch Ophthalmol. 2010;128:478-482.
MedScape Today by Laurie Barclay, MD, 4/12/2010