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Background Hearing and vision impairments are risk factors for cognitive decline; less is known about dual sensory impairment. This study quantifies the association between dual sensory impairment and 8‐year change in memory among older adults. Methods Data (N = 5552) were from the National Health and Aging Trends Study. Memory (immediate/delayed word recall, subjective memory) was measured annually (2011 to 2019). Hearing and vision impairments were measured by self‐report. Association between dual sensory impairment and 8‐year change in memory was assessed using multivariate linear mixed effect models and generalized logistic mixed models. Results Rate of memory decline was most accelerated among participants with dual sensory impairment. For example, 8‐year decline in delayed word recall was −1.03 (95% confidene interval: ‐1.29, ‐0.77) for dual sensory impairment versus ‐0.79 (‐0.92, ‐0.67) for single and −0.56 (‐0.63, ‐0.48) for no impairment. Conclusion Older adults with dual sensory impairment may be at particularly higher risk for cognitive decline.

A primary goal of longitudinal studies is to examine trends over time. Reported results from these studies often depend on strong, unverifiable assumptions about the missing data. Whereas the risk of substantial bias from missing data is widely known, analyses exploring missing-data influences are commonly done either ad hoc or not at all. This article outlines one of the three primary recognized approaches for examining missing-data effects that could be more widely used, i.e. the shared-parameter model (SPM), and explains its purpose, use, limitations and extensions. We additionally provide synthetic data and reproducible research code for running SPMs in SAS, Stata and R programming languages to facilitate their use in practice and for teaching purposes in epidemiology, biostatistics, data science and related fields. Our goals are to increase understanding and use of these methods by providing introductions to the concepts and access to helpful tools.

Introduction Slower mobility is associated with mild cognitive impairment (MCI) and dementia. We examined the interaction of endurance with gait speed on prevalent MCI and dementia. Methods Cross‐sectional multinomial regression in the ARIC cohort (n = 2844 participants; 71 to 94 years; 44% men; 18% Black persons) with cognitive status (normal/MCI/dementia), 4 m gait speed, and endurance (2 minute walk [2MW]). Results Faster gait speed (up to but not above 1 m/s) and better 2MW were separately associated with lower dementia risk. Good performance in both (2MW = 200 m, gait speed = 1.2 m/s) was associated with 99% lower dementia (Relative Prevalence Ratio [RPR] = 0.01 [95% CI: 0.0 to 0.06]) and 73% lower MCI, RPR = 0.27 (0.15 to 0.48) compared to poor performance in both (2MW = 100 m, gait speed = 0.8 m/s). Models incorporating a gait speed‐by‐2MW interaction term outperformed gait speed‐only models (P < .001). Discussion Gait speed relationships with dementia diminish at faster gait speeds. Combining endurance with gait speed may yield more sensitive markers of MCI and dementia than gait speed alone.