Area-Level Infant Mortality Exposure in Early Life and Later Life Stroke: The Role of Modifiable Risk Factors and Place of Birth

Abstract A growing literature suggests that early life conditions may contribute to the risk of later life stroke. In this paper we explore the role that infant mortality (as a proxy for environmental and socioeconomic conditions) plays in later life self-reported stroke and stroke mortality, while also considering other contextual factors such as state of birth. We use a sample of 244,041 individuals aged 60 and above with the NIH-AARP Diet and Health Study with 16 years of mortality follow-up, allowing us to examine the role that infant mortality rates, along with other known risk factors, play in one’s individual risk of stroke mortality and self-reported stroke. We show using logistic regression models for stroke incidence and cox proportional hazard models for stroke mortality, that infant mortality rates are associated with later life stroke mortality among males, net of controls for education, and stroke risk factors, and with self-reported stroke among females, prior to controlling for risk factors. However, upon controlling for state of birth, these associations dissipate. Our findings suggest that early life factors in the form of infant mortality are important considerations when studying the risk of stroke death for males, for reporting a history of strokes among females and how failure to consider these early life contextual influences may overstate these associations with morbidity and mortality. Competing Interest Statement The authors have declared no competing interest. Funding Statement This research was carried out using the facilities of the Center for Demography and Ecology and Center, supported by Eunice Kennedy Shriver National Institute of Child Health and Human Development grant P2C HD047873 and the Center for Demography of Health and Aging, which is supported by National Institute on Aging grant P30 AG017266. Topping also received support by the National Institute on Aging training grant T32 AG000129. Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study received approval from the University of Wisconsin-Madison Institutional Review Board. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data Availability All data produced in the present work are restricted, given the use of geographic identifiers.