Abstract
Purpose: :
Primary open angle glaucoma (POAG) is known to demonstrate a hereditary pattern. The pattern and severity of POAG among first degree relatives were evaluated and compared.
Methods: :
A cohort study of patients with POAG (high-pressure OAG), NTG (Normal Tension Glaucoma), OHT (Ocular Hypertension) were followed, and their first degree relatives.Eighteen families of first degree relatives (18 parent/ 18 children and a pair of identical twins) with OAG were reviewed. The pattern of glaucoma within each family was compared, with regard to the type of glaucoma (POAG, NTG or OHT), age at diagnosis, and the amount of glaucomatous damage evaluated by optic disc excavation and glaucomatous visual field defects (GVFD). Visual field damage severity was quantified: 0 (normal VF), 1-mild (superior/inferior actuate /nasal step), 2 (2 GVFD) and 3 - severe (more than 2 GVFD).
Results: :
Mean age at diagnosis in the parent group was 73.2 (range 65-85±5.11) and 48.1 (range 34-61±8.48) in the child group (p<0.01). Mean cup-disc ratio was 0.68 in the parent group and 0.57 in the child group (p=0.59). Calculated VF damage severity was 1.67 in the parent group and 1.03 in the child group (p<0.05). Amongst the parents 15 had high-pressure OAG and 3 NTG; among the children 3 OHT, 12 high-pressure OAG and 3 NTG. As for the twins one has high-pressure OAG and the other NTG.
Conclusions: :
First-degree relatives may have high-pressure OAG, NTG or OHT among the members of the same family. Previous research shows that glaucoma severity is more advanced in patients with family history of glaucoma. Large VCD was one of the first characteristics of glaucoma among relatives. Our findings support this notion as there was no significant difference in the VCD among the 2 groups, while there was a significant difference in age at diagnosis, which means more advanced cupping in the second generation. Relatives of glaucoma patients should be screened for glaucoma at a relatively young age, since POAG (high-pressure OAG, NTG and OHT) in the second generation might commence earlier and may result in more significant damage at the time of diagnosis.
Keywords: clinical (human) or epidemiologic studies: outcomes/complications • genetics