Age‐related change in contrast sensitivity among Australian male adults: Florey Adult Male Ageing Study

Abstract

. Purpose: To describe the age‐related change in contrast sensitivity seen in 35‐ to 80‐year‐old men in an Australian population. Methods: The Florey Adelaide Male Ageing Study (FAMAS) is a prospective population‐based study of men aged 35–80 years randomly selected from the north‐west suburbs of Adelaide. We conducted a nested ophthalmic substudy of these men. Contrast sensitivity (CS) was measured at four spatial frequencies (3, 6, 12 and 18 cycles/degree [cpd]) using the Vectorvision CSV‐1000 contrast sensitivity test chart (Vectorvision, Dayton, OH, USA), and results were statistically analysed relative to age and cataract type. Results: There were 2650 eligible subjects in the FAMAS and 1195 participated (45.1%); 472 of those participated in the ophthalmic substudy. A statistically significant decrease in contrast sensitivity was seen with advancing age at each spatial frequency tested [Generalized estimating equations (GEE) multiple linear regression: p ≤ 0.01]. The decline with age was greatest in the highest spatial frequency (18 cpd) and least in the lowest spatial frequency (3 cpd). Posterior subcapsular cataract caused the greatest reduction in contrast sensitivity at all spatial frequencies, while nuclear cataract caused significant reduction only in the intermediate (12 cpd) and high (18 cpd) spatial frequencies. Cortical cataract failed to reach statistical significance in contrast sensitivity reduction at all spatial frequencies tested. Conclusion: Contrast sensitivity declines with age in all spatial frequencies tested with a greater decline occurring in the higher spatial frequencies. Age and cataracts are independently associated with contrast sensitivity decline, and posterior subcapsular cataracts caused the greatest reduction at all spatial frequencies.

Method for Adapting the Grayscale Standard Display Function to the Aging Eye

“…[6], both for its model and for the comparison experiments he referred to, are significantly larger than those found in refs. [24] and [25]. This may be due to the different testing procedures (sine grating targets vs. optician charts).…”

“…In ref. [24], the test distance is 2.5 m, which is quite large if compared to the distance of the observer of a radiology display; the luminance of the target is 85 cd/m 2 , while a radiology display provides a large range of luminance values, above and (more importantly) much below such a value. On the other hand, ref.…”

“…A study presented in ref. [24] correlates the decrease in CSF to the presence of early cataract which could explain the large dispersion of the results when, instead, only age is taken into account. The resulting values are shown in Fig.…”

“…Results from a large set of experiments on the aging eye have been recently presented in two separate studies: a report about 472 Australian male subjects aged 35-80 years [24], Fig. 2 Pupil diameter as a function of the luminance to which the visual system is adapted, according to the three models mentioned in the text Fig.…”

“…[24] and [25]. The maximum value of the CSFs for the youngest subjects can be derived, and k chosen to make the model coincide at this point.…”