Correctable visual impairment in an older population: the blue mountains eye study.

PURPOSE: To describe temporal changes in the characteristics of older persons with visual impairment in their better eye correctable by refraction.

DESIGN

Study of two cross sections of a community 6 years apart.

METHODS

The Blue Mountains Eye Study examined 3654 persons aged 49 to 97 during 1992 to 1994 (cross-section 1) and 3509 persons (2335 cohort survivors plus 1174 persons who moved to the area and age group) during 1997 to 2000 (cross-section 2). Logarithm of minimal angle of resolution visual acuity was measured before and after refraction. Correctable visual impairment was defined as visual impairment < 20/40 in the better eye before refraction that improved after refraction to no impairment (>/= 20/40). Factors associated with correctable visual impairment and persistent correctable impairment were determined.

RESULTS

Cross-sections 1 and 2 had similar age-gender distributions. In cross-section 1, 7.5% of participants had correctable visual impairment, 3.6% had noncorrectable visual impairment, and 88.9% had no impairment. Corresponding rates in cross-section 2 were 5.6%, 2.7%, and 91.7%. In both cross sections, similar proportions (around 68%) of those visually impaired had correctable visual impairment and similar sociodemographic measures predicted correctable visual impairment. Cross-section 1 participants who were married, owned their home, had high job prestige, gained qualifications after high school, or were current drivers were less likely to have correctable visual impairment after controlling for age and gender. Adjusted odds for correctable visual impairment increased in those living alone, using community support services, dependent on others, with myopia, wearing distance glasses, or with low perceived health and heart disease. Histories of stroke, cancer, and diabetes were similar between groups with correctable and no visual impairment.

CONCLUSION

Socioeconomic parameters, myopia, wearing distance glasses, reported health problems, and poor perceived health were associated with correctable visual impairment in this older population.