Aims: The purpose of this study was to determine the refractive status and ocular health of a group of patients with Down's syndrome, all over the age of 40, with possible involvement of Alzheimer's disease (AD). We also aimed to compare the results obtained from sufferers and non-sufferers of the disease.
Patients and methods: We examined 49 patients, between 40 and 62 years of age. The visual examination consisted in visual acuity (VA) measurement, binocularity test, ocular motility, retinoscopy, ocular health and subjective examination.
Results: Of the 49 patients studied, 24.5% were diagnosed as suffering from AD and were treated accordingly; 4% of the patients diagnosed as suffering from the disease were unable to go on with the treatment for a number of different reasons and 8.2% were at the limit of being diagnosed. 68.7% of the patients presented VA in long distance sight below 0.5 and 48% had values below 0.4 in near sight. Results showed 61.4% myopias, 45.8% astigmatisms and 23% hyperopias. 31.2% of the patients showed signs of needing prescription regarding near sight. 66.7% presented strabismus and altered motility. The main pathologies found were: 59.4% of crystalline opacities, 25% nystagmus, 13.5% interventions due to cataracts, and 6.2% keratoconus, among others.
Conclusions: Diagnosis of AD is a very complex task in this population due to the heterogeneity of the level of retardation, the presence of concomitant psychiatric diseases and associated sensory problems. Findings confirm the high incidence among this population of ametropias and pathologies, especially cataracts, and VA values outside the functional limits both in far and near sightedness. No significant differences were found among patients who had been diagnosed and those who had not been diagnosed as suffering from AD.