Abstract
Abstract: :
Purpose: To study the familiar history of amblyopia children, such study may be the basis of future genetic study. Method: Case- control study of two hospitals: hospital 1 is a center hospital and hospital 2 is a local hospital. Study time: six months from Dec.1990 to May.1991. Case and control groups were all selected from the under ten years-old patients who visited ophthalmic clinics of the two hospitals during the above study time. Case group had the criteria of amblyopia, and subgroups were made as one of following criteria: strabismus, hyperopia ≷ + 3.0D, astigmatism ≷ 2.0D, myopia ≷ -7.0 D, or anisometropia as hyperopic ≷ 1.0 D, astigmatic ≷ 2D, myopic ≷ -6D or other causes. Control group had all the following criteria: no amblyopia, no strabismus, the refraction error must be hyperopia < 1.5 D, astigmatism < 1.0 D, no myopia and normal stereopsis. The familiar study included three direct generations data from grand parents, parents, and siblings. We inquired the above family if they had amblyopia and whether the same cause of amblyopia as the child. The statistic analysis method was Fisher Exact chi-square test (STATA 7). Result: Hospital 1 has 207 cases and 41 controls. The family amblyopia ratios are: 4.9% in the control vs. 5.9% in case group of grandparents; 2.4% in the control vs. 14.5% (p= 0.036) in case group of parents; and 3.3% in the control vs. 15.5% (p= 0.088) in case group of sibling. The family aggregation of amblyopia is more prominent in the hyperopia and astigmatism subgroups. In the hyperopia subgroup (69 cases), the parents amblyopia ratio is 18.8% (Odds ratio: 9.3, p=0.016) and the sibling amblyopia ratio is 22.4% (Odds ratio: 8.4, p= 0.029). In the astigmatism subgroup (41 cases), the parents ratio is 22.0% (Odds ratio: 0.014, p= 0.014) and the sibling amblyopia ratio is 22.9% (Odds ratio: 8.6, p= 0.031). Hospital 2 has 54 cases and 24 controls. The family amblyopia ratios are: 4.2% in the control vs. 7.4% in case group of grandparents; 12.5% in the control vs. 14.8% in case group of parents; and 0% in the control vs. 25.6% (p= 0.051) in case group of sibling. In the hyperopia subgroup (17 cases), the parents amblyopia ratio is 23.5% and the sibling amblyopia ratio is 42.9% (p= 0.016). And the sibling amblyopia ratio of the astigmatism subgroup is 35.7% (p= 0.041). The ratio of the same cause of amblyopia between amblyopia parents and their child is 85% and 77.1% between amblyopia sibling. Conclusions: The familiar aggregation ratios are higher in hyperopia and astigmatism amblyopia children.
Keywords: 313 amblyopia • 350 clinical (human) or epidemiologic studies: biostatistics/epidemiology methodology