[Plasma and erythrocyte zinc concentrations in elderly patients with and without senile cataract in a tertiary eye care center at Teresina-Piauí].

Purpose: To determine plasma and erythrocyte zinc concentrations in elderly with and without senile cataract in a tertiary eye care center at Teresina-Piauí.

Methods: A quantitative, transversal and controlled study was developed at the Hospital de Olhos Francisco Vilar, Piauí, Brasil. Fifty-six elderly subjects (37 females, 19 males) with no known conditions that modify zinc blood levels or increase risk of cataract were included. A score >II was used to define cataract, according to Lens Opacities Classification System II. Plasma and erythrocyte zinc concentrations were determined by flame atomic absorption spectrometry. Statistical tests included Student's t and chi-square tests, with a probability level of 0.05 as significant.

Results: Senile cataract was present in 58.9% of the subjects. The most common type was nuclear (51.8%), followed by cortical (26.8%) and posterior subcapsular (8.9%). Zinc deficiencies in plasma (<70 microg/dL) and erythrocyte (<40 microg/gHb) were found in 49.1% and 30.4% of participants, respectively. There were no significant differences between elderly with or without cataract, regardless of type, in relation to plasma (p=0.165) or erythrocyte (p=0.426) zinc concentrations.

Conclusion: Zinc deficiency in plasma or erythrocyte were common among the elderly. However, the data suggest that no significant differences exist between elderly with or without senile cataract, regardless of type, in relation to the referred parameters of zinc evaluation.