Ethnicity influences vision-specific functioning in AMD
Ethnicity appears to independently influence the association between age-related macular degeneration (AMD) and vision-specific functioning (VSF), according to a Singapore study.
“We found ethnic differences in the association between AMD and VSF that are independent of factors traditionally associated with vision-related quality of life, such as [visual acuity] and socioeconomic status,” said the researchers.
Between 2004 and 2011, researchers obtained data on 10,033 individuals aged 40–80 years of three major Asian ethnicities in Singapore (Chinese, Malay, and Indian) from the cross-sectional, population-based SEED* study. Of these, 99.3 percent (n=9,962, mean age 58.8 years, 49.3 percent male) had gradable fundus images and Visual Function Index (VF-11**) questionnaire data. [JAMA Ophthalmol 2017;doi:10.1001/jamaophthalmol.2017.0266]
About 6 percent of subjects (n=590) had early AMD (241 Chinese, 161 Malay, and 188 Indian participants), while 0.6 percent (n=60) had late AMD (25 Chinese, 21 Malay, and 14 Indian participants).
Mean VSF scores were highest in Chinese participants (4.05), followed by Indian (3.67) and Malay participants (3.63), with individuals with no or early AMD having better VSF than individuals with late AMD (mean 3.69 vs 2.92; p<0.001).
Early AMD was associated with a minor reduction in VSF score, but only in the Chinese population of study subjects (2.9 percent, β= -0.12, 95 percent confidence interval [CI], -0.23 to -0.00; p=0.046) compared with those with no AMD.
Reduction in VSF scores was also significant in the Chinese population with late AMD (19.1 percent, β= -0.78, 95 percent CI, -1.13 to -0.43; p<0.001) and borderline significant in the Malay population (13.5 percent, β= -0.49, 95 percent CI, -1.01 to 0.04; p=0.07) compared with those with no AMD, with no association observed between VSF and late AMD in the Indian population (p=0.68).
VSF scores progressively reduced with the worsening of AMD in the Chinese (mean 4.07, 3.91, and 3.00; p<0.001 for no AMD, early AMD, and late AMD, respectively) and Malay populations (mean 3.64, 3.51, and 2.51; p<0.001 for no AMD, early AMD, and late AMD, respectively), while the reduction in mean VSF score with AMD progression in the Indian population was not statistically significant (p=0.37).
“This information is important for clinicians, researchers, and policy planners in designing culturally sensitive interventions to improve participation in daily living activities for different ethnic groups with AMD,” said the researchers.
“More research is needed to elucidate the underlying pathophysiological, behavioural, psychosocial, and cultural reasons behind the ethnic differences reported in our study,” they said, while also recommending the creation of ethnicity-based strategies to delay AMD onset and progression.
“The patient’s perspective is important to meeting health care needs in an era of patient-centred care,” said Dr Lisa Keay from The George Institute for Global Health, The University of Sydney, New South Wales, Australia, in a separate editorial. [JAMA Ophthalmol 2017;doi:10.1001/jamaophthalmol.2017.0272]
“However, if self-reporting of visual function varies by ethnicity, it lends uncertainty to how accurately visual function is being reported,” she said, calling for research into identifying the reasons for ethnic variations in visual function reporting.