Adverse outcomes after partner bereavement in people with reduced kidney function: Parallel cohort studies in England and Denmark.

Objectives: To investigate whether partner bereavement is associated with adverse cardiovascular and kidney-related events in people with reduced kidney function.
Design: Two parallel matched cohort studies using linked routinely collected health data.
Setting: England (general practices and hospitals using linked Clinical Practice Research Datalink, Hospital Episode Statistics, and Office of National Statistics) and Denmark (hospitals and community pharmacies using the Danish National Patient, Prescription and Education Registries and the Civil Registration System).
Participants: Bereaved people with reduced kidney function (estimated glomerular filtration rate (eGFR) <60mL/min/1.73m2 (England) or hospital-coded chronic kidney disease (Denmark)) and non-bereaved people with reduced kidney function similarly defined, matched on age, sex, general practice (England), and county of residence (Denmark) and followed-up from the bereavement date of the exposed person.
Main Outcome Measures: Cardiovascular disease (CVD) or acute kidney injury (AKI) hospitalization, or death.
Results: In people with reduced kidney function, we identified 19,820 (England) and 5,408 (Denmark) bereaved individuals and matched them with 134,828 (England) and 35,741 (Denmark) non-bereaved individuals. Among the bereaved, the rates of hospitalizations (per 1000 person-years) with CVD were 31.7 (95%-CI: 30.5-32.9) in England and 78.8 (95%-CI: 74.9-82.9) in Denmark; the rates of hospitalizations with AKI were 13.2 (95%-CI: 12.5-14.0) in England and 11.2 (95%-CI: 9.9-12.7) in Denmark; and the rates of death were 70.2 (95%-CI: 68.5-72.0) in England and 126.4 (95%-CI: 121.8-131.1) in Denmark. After adjusting for confounders, we found increased rates of CVD (England, HR 1.06 [95%-CI: 1.01-1.12]; Denmark, HR 1.10 [95%-CI: 1.04-1.17]), of AKI (England, HR 1.20 [95%-CI: 1.10-1.31]; Denmark HR 1.36 [95%-CI: 1.17-1.58]), and of death (England, HR 1.10 [95%-CI: 1.05-1.14]; Denmark HR 1.20 [95%-CI: 1.15-1.25]) in bereaved compared with non-bereaved people.
Conclusions: Partner bereavement is associated with an increased rate of CVD and AKI hospitalization, and death in people with reduced kidney function. Additional supportive care for this at-risk population may help prevent serious adverse events.
Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: All authors have completed an ICJME disclosure form. AH, PB, AK, AYSW, SAJS declare no competing interests, including relevant financial interests, activities, relationships or affiliations. SVV was supported by The Beckett Foundation by a grant administered by Aarhus University which supported this manuscript. DN is the UK Renal Association Director of Informatics Research, a member of the steering group for two GlaxoSmithKline funded studies of kidney function in Sub-Saharan Africa and receives funding from the Health Foundation and the Medical Research Council unrelated to the work in this paper. SVV, CFC, and AK are members of Aarhus University Department of Clinical Epidemiology and are involved in studies with funding from various companies as research grants to (and administered by) Aarhus University. SML is funded by a Wellcome Senior Clinical Fellowship in Science (205039/Z/16/Z) and was funded by the European Academy of Dermatology and Venerology (PPRC-2016-019) for previous bereavement-related research. SL has received consulting fees from STAART-AKI Study Group (reviewing patient information sheets) and the NIHR (lay reviewer), has received payments for medical writing or editing from Kidney Care UK, ERA-EDTA for work unrelated to this manuscript. SL has also received support for travel at ERA-EDTA Congress 2018 and 2019 unrelated to this work. SL is also chair of the UK Renal Association Patients’ Council and the Guy’s & St Thomas’ Kidney Patients’ Association.