Nine-year changes in intraocular pressure - The Barbados eye studies

Objective: To describe temporal changes in intraocular pressure (IOP) and associated risk factors after 9 years of follow-up in a population of African descent. Methods: Changes in IOP were evaluated in 2298 participants without glaucoma or IOP-lowering treatment at baseline. Risk factor analyses used a multiple regression approach with mixed effects, which accounted for intereye correlation. Results: The mean 9-year change in IOP was small, with relatively large dispersion (mean +/- SD, 0.4 +/- 4.0 mm Hg). Only 6.5% of persons with IOP of 21 mm Hg or less at baseline had elevated IOP greater than 21 mm Hg after 9 years. Mean IOP increases were largest in persons aged 50 to 59 years at baseline (mean +/- SD, 0.9 +/- 4.3 mm Hg), whereas IOP decreased in persons 70 years or older (mean +/- SD, -0.6 +/- 4.2 mm Hg). In multivariate analyses, IOP changes were positively associated with male sex, hypertension, diabetes history, and higher systolic and diastolic blood pressure at baseline, as well as with increases in blood pressure throughout 9 years (P < .05). Conclusions: After long-term follow-up, minimal changes in IOP were observed in this African-origin population. The consistent relationships of hypertension and diabetes to IOP, a major glaucoma risk factor, underscore the public health importance of controlling these systemic conditions in black populations, where glaucoma incidence is high.