TY - JOUR T1 - Accounting for selection bias due to death in estimating the effect of wealth shock on cognition for the Health and Retirement Study. JF - Statistics in Medicine Y1 - 2021 A1 - Yaoyuan V. Tan A1 - Carol A C Flannagan A1 - Lindsay R Pool A1 - Michael R. Elliott KW - Bayesian additive regression trees KW - Causal inference KW - Missing data AB -

The Health and Retirement Study (HRS) is a longitudinal study of U.S. adults enrolled at age 50 and older. We were interested in investigating the effect of a sudden large decline in wealth on the cognitive ability of subjects measured using a dataset provided composite score. However, our analysis was complicated by the lack of randomization, time-dependent confounding, and a substantial fraction of the sample and population will die during follow-up leading to some of our outcomes being censored. The common method to handle this type of problem is marginal structural models (MSM). Although MSM produces valid estimates, this may not be the most appropriate method to reflect a useful real-world situation because MSM upweights subjects who are more likely to die to obtain a hypothetical population that over time, resembles that would have been obtained in the absence of death. A more refined and practical framework, principal stratification (PS), would be to restrict analysis to the strata of the population that would survive regardless of negative wealth shock experience. In this work, we propose a new algorithm for the estimation of the treatment effect under PS by imputing the counterfactual survival status and outcomes. Simulation studies suggest that our algorithm works well in various scenarios. We found no evidence that a negative wealth shock experience would affect the cognitive score of HRS subjects.

VL - 40 IS - 11 ER - TY - RPRT T1 - Accounting for selection bias due to death in estimating the effect of wealth shock on cognition for the Health and Retirement Study Y1 - 2018 A1 - Yaoyuan V. Tan A1 - Carol A C Flannagan A1 - Lindsay R Pool A1 - Michael R. Elliott KW - Cognition & Reasoning KW - Survey Methodology KW - Wealth Shocks AB - The Health and Retirement Study is a longitudinal study of US adults enrolled at age 50 and older. We were interested in investigating the effect of a sudden large decline in wealth on the cognitive score of subjects. Our analysis was complicated by the lack of randomization, confounding by indication, and a substantial fraction of the sample and population will die during follow-up leading to some of our outcomes being censored. Common methods to handle these problems for example marginal structural models, may not be appropriate because it upweights subjects who are more likely to die to obtain a population that over time resembles that would have been obtained in the absence of death. We propose a refined approach by comparing the treatment effect among subjects who would survive under both sets of treatment regimes being considered. We do so by viewing this as a large missing data problem and impute the survival status and outcomes of the counterfactual. To improve the robustness of our imputation, we used a modified version of the penalized spline of propensity methods in treatment comparisons approach. We found that our proposed method worked well in various simulation scenarios and our data analysis. JF - Statistics > Applications PB - arXiv.org CY - Ithaca UR - https://arxiv.org/abs/1812.08855 ER - TY - JOUR T1 - Association of a Negative Wealth Shock With All-Cause Mortality in Middle-aged and Older Adults in the United States. JF - JAMA Y1 - 2018 A1 - Lindsay R Pool A1 - Sarah A. Burgard A1 - Belinda L Needham A1 - Michael R. Elliott A1 - Kenneth M. Langa A1 - Carlos F. Mendes de Leon KW - Mortality KW - NDI KW - Wealth Shocks AB -

Importance: A sudden loss of wealth-a negative wealth shock-may lead to a significant mental health toll and also leave fewer monetary resources for health-related expenses. With limited years remaining to regain lost wealth in older age, the health consequences of these negative wealth shocks may be long-lasting.

Objective: To determine whether a negative wealth shock was associated with all-cause mortality during 20 years of follow-up.

Design, Setting, and Participants: The Health and Retirement Study, a nationally representative prospective cohort study of US adults aged 51 through 61 years at study entry. The study population included 8714 adults, first assessed for a negative wealth shock in 1994 and followed biennially through 2014 (the most recent year of available data).

Exposures: Experiencing a negative wealth shock, defined as a loss of 75% or more of total net worth over a 2-year period, or asset poverty, defined as 0 or negative total net worth at study entry.

Main Outcomes and Measures: Mortality data were collected from the National Death Index and postmortem interviews with family members. Marginal structural survival methods were used to account for the potential bias due to changes in health status that may both trigger negative wealth shocks and act as the mechanism through which negative wealth shocks lead to increased mortality.

Results: There were 8714 participants in the study sample (mean [SD] age at study entry, 55 [3.2] years; 53% women), 2430 experienced a negative wealth shock during follow-up, 749 had asset poverty at baseline, and 5535 had continuously positive wealth without shock. A total of 2823 deaths occurred during 80 683 person-years of follow-up. There were 30.6 vs 64.9 deaths per 1000 person-years for those with continuously positive wealth vs negative wealth shock (adjusted hazard ratio [HR], 1.50; 95% CI, 1.36-1.67). There were 73.4 deaths per 1000 person-years for those with asset poverty at baseline (adjusted HR, 1.67; 95% CI, 1.44-1.94; compared with continuously positive wealth).

Conclusions and Relevance: Among US adults aged 51 years and older, loss of wealth over 2 years was associated with an increased risk of all-cause mortality. Further research is needed to better understand the possible mechanisms for this association and determine whether there is potential value for targeted interventions.

VL - 319 IS - 13 U1 - http://www.ncbi.nlm.nih.gov/pubmed/29614178?dopt=Abstract ER - TY - JOUR T1 - Negative wealth shock and short-term changes in depressive symptoms and medication adherence among late middle-aged adults. JF - Journal of Epidemiology and Community Health Y1 - 2017 A1 - Lindsay R Pool A1 - Belinda L Needham A1 - Sarah A. Burgard A1 - Michael R. Elliott A1 - Carlos F. Mendes de Leon KW - Depressive symptoms KW - Middle age KW - Prescription Medication KW - Wealth Shocks AB -

BACKGROUND: Experiencing a negative wealth shock in late middle age may cause high levels of stress and induce reductions in health-related consumption.

METHODS: We used data on late middle age individuals (51-64 years) from the longitudinal US-based Health and Retirement Study (N=19 281) to examine the relationship between negative wealth shock and short-term outcomes that serve as markers of the pathways from wealth shock to health: elevated depressive symptoms, as a marker of the stress pathway and cost-related medication non-adherence (CRN), as a marker of the consumption pathway. Negative wealth shock was considered to be a loss of total net worth of 75% or more.

RESULTS: Using a nested cross-over approach-a within-person design among exposed individuals only that adjusts by design for all time-invariant individual characteristics-we found that negative wealth shock was significantly associated with increased odds of elevated depressive symptoms (OR=1.50, CI 1.10 to 2.05), but was not significantly associated with higher odds of CRN (OR=1.18, CI 0.76 to 1.82), even after further adjustment for time-varying sociodemographic and health covariates.

CONCLUSIONS: Negative wealth shock during late middle age confers an increased risk of elevated depressive symptoms, but does not change levels of CRN. Personal and policy factors that may buffer the mental health risks of negative wealth shock, such as social support and social welfare policy, should be considered.

VL - 71 IS - 8 U1 - http://www.ncbi.nlm.nih.gov/pubmed/28416571?dopt=Abstract ER - TY - THES T1 - The Health Consequences of Negative Wealth Shock During Late Middle Age T2 - Epidemiological Science Y1 - 2016 A1 - Lindsay R Pool KW - Health Conditions and Status KW - Health Shocks KW - Income KW - Medicare/Medicaid/Health Insurance KW - Older Adults KW - Wealth Shocks AB - There is robust empirical evidence for a link between lower economic status and adverse health outcomes, but little is known about whether a sudden, unplanned loss of assets – a negative wealth shock – has long-term health consequences. Previous research has shown associations between negative wealth shocks and short-term health declines, primarily from losses of housing and investment wealth, with macroeconomic recession presumed to have triggered these shocks. Even during better economic times, however, negative wealth shocks arise frequently from more individualized circumstances, such as high medical expenses, but causal mechanisms linking subsequent health outcomes to these endogenous shocks can be difficult to establish due to the potential for reverse causality and residual confounding. Using data from the Health and Retirement Study, a nationally representative study of US adults aged 50 and older, this dissertation examined markers of short-term changes in stress and health care consumption after negative wealth shock in late middle age, a time of particular vulnerability. Then, differences by whether an individual experienced negative wealth shock in late middle age were assessed for three long-term aging-related trajectories – cognitive decline, physical function limitation accumulation, and all-cause mortality. Design and analytic methods addressed bidirectional and time-dependent causation in the relationship between negative wealth shock and health outcomes. Over 15 percent of late middle-aged adults with existing assets experienced negative wealth shock. The main findings indicated that experiencing a negative wealth shock during late middle age was associated with a higher risk of elevated depressive symptoms, a marker of increased stress, as well as long-term risk of mortality and cognitive decline. However, there was no significant association between negative wealth shock and risk of cost-related medication non-adherence – a marker of reduced health-related consumption, nor accelerated physical function limitation accumulation. With a substantial proportion of the late middle-aged population experiencing negative wealth shock, targeted interventions to prevent of the occurrence of these shocks and the health consequences thereafter may have a large impact on the health of older Americans JF - Epidemiological Science PB - University of Michigan CY - Ann Arbor VL - Ph.D. SN - 9781369082029 UR - http://proxy.lib.umich.edu/login?url=http://search.proquest.com/docview/1817658414?accountid=14667 ER -