title: Trajectories of vision in older people: the role of age and social position.
abstract: Visual impairment becomes more prevalent with age. Rather than a uniform decline in vision with age, the strength and direction of change varies between people. This study applies an analytical method that posits multiple trajectories in eyesight, allowing for a more specific description of developmental course of this health outcome and its relationship with social position. The analysis uses the responses of 2956 respondents, aged 60 years and over, followed over 8 years (five observations) as part of the English longitudinal study of ageing. At each observation respondents self-reported their general vision. Optimal matching (sequence analysis), hierarchical clustering, and multinomial logistic regression were used to describe the sequential data, produce a typology of vision trajectories, and examine the socio-demographic characteristics associated with different trajectories. Eight distinctive clusters of trajectories were identified. The probability of reporting different types of vision trajectory varies with a change in age; however, the magnitude of the age effect is associated with social position. Visual impairment in older people is an increasingly relevant area for policy focus, with the rapid growth and diversity of the older population. Identifying factors underpinning the patterning of changes in visual function is essential for developing evidence-based policy, which both meets the needs of those most at risk and increases cost-effectiveness of public health interventions.
authors.affiliation: The Cathie Marsh Institute for Social Research (CMIST), School of Social Sciences, University of Manchester, Humanities Bridgeford Street-G18, Manchester, M13 9PL UK.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Whillans
authors.affiliation: The Cathie Marsh Institute for Social Research (CMIST), School of Social Sciences, University of Manchester, Humanities Bridgeford Street-G29, Manchester, M13 9PL UK.
authors.forename: James
authors.initials: J
authors.lastname: Nazroo
authors.affiliation: The Cathie Marsh Institute for Social Research (CMIST), School of Social Sciences, University of Manchester, Humanities Bridgeford Street-G21, Manchester, M13 9PL UK.
authors.forename: Katey
authors.initials: K
authors.lastname: Matthews
keywords: Health inequality; Longitudinal study; Optimal matching; Self-reported vision; Sequence analysis; Visual function