Authors: Xiuhua Ding, Erin L Abner, Frederick A Schmitt, Richard J Kryscio
Published: 2020-12-07
DOI: 10.1002/alz.037617
Source: Full article
AbstractBackgroundThe Medical Outcomes Study Questionnaire Short Form 36 health survey (SF‐36) measures health‐related quality of life (QOL) from the patient’s point of view and is an indicator of overall health status. QOL measures may show differential changes over time prior to dementia onset.MethodsWe analyzed data from the Prevention of Alzheimer’s Disease (AD) by Vitamin E and Selenium (PREADViSE) trial, which recruited 7,547 non‐demented men between 2002 and 2009. A subset of 2,746 PREADViSE participants who completed up to five SF‐36 assessments at annual visits were included in the current analysis. Two summary scores were generated for analysis: physical component score (PCS) and mental component score (MCS), each with a mean 50 with standard deviation of 10. Linear mixed models (LMM) were applied to determine how SF‐36 scores varied over time and by eventual dementia status. Cox proportional hazards regression was used to determine if the baseline SF‐36 scores were associated with dementia incidence, adjusting for baseline age, race, APOE‐4 status, diabetes, and self‐reported memory complaint at baseline.ResultsThe mean of MCS at baseline for subjects with dementia diagnosis later (mean± SD: 53.86±9.47) was significantly lower than for subjects without dementia diagnosis (mean± SD: 56.42±6.48) (p = 0.005), while the means of PCS at baseline (Dementia: 49.31±7.93 vs. Non‐dementia: 49.77±7.81) were not significantly different (p = 0.54). The LMM analysis showed a significant effect only for time in PCS. For MCS, the indicator for dementia was significantly associated with poorer self‐reported mental health after adjusting baseline age, black race, and memory complaint. Given adjustments for other risk factors, results from the Cox model showed that a 10‐unit increase in MCS was associated with a 44% decrease in the hazard of a future dementia diagnosis (95% CI: 32%‐55%).ConclusionThe SF‐36 MCS summary score may be a predictor for future dementia and could be useful in longitudinal dementia research.