U.S. AND UK DIFFERENCES IN THE ASSOCIATION BETWEEN MULTIMORBIDITY TRAJECTORIES AND RETIREMENT IN OLDER WORKERS WITH HIGH AND LOW EFFORT-REWARD IMBALANCE

Background Previous research has indicated that effort rewardimbalance (ERI) is independently associated with retirement
and cross-sectional multimorbidity. In addition, aging populations and pension reform across western societies has led to
older adults who are at increased risk of aging related disease
onset and progression, participating in the labour force for
longer. The objective of this study was to examine the association between multimorbid chronic health trajectories and
retirement in older workers experiencing high and low effortreward imbalance.
Methods This study used longitudinal data from the Health
and Retirement Study (2006–2016) and the English Longitudinal Study of Ageing (2004–2014) for adults aged 50–55
years. Group-based trajectory modelling was used to construct multimorbidity trajectories (0–6 of diabetes, hypertension, heart disease, stroke, lung disease and cancer) over a
10-year period separately for participants reporting low and
high ERI at baseline. Logistic regression analysis fully adjusted for relevant variables examined the association
between the multimorbidity trajectories and cross-sectional
retirement at the final wave.
Results Mean ERI scores were higher in UK workers (low ERI
= 0.75, high ERI = 1.38), compared to U.S. workers (low
ERI = 0.67, high ERI = 1.32). Four trajectory classes were
identified for U.S. workers with low ERI (no conditions, noincreasing, low-increasing, and high-stable). Compared to the
no conditions trajectory, the high stable trajectory was associated with retirement (HR=4.50, 95%CI=2.08–9.62). Four trajectory classes (no-increasing, low-increasing, medium-stable, and
high increasing) were identified for U.S. participants with high
ERI. The medium-stable (HR=3.14, 95%CI = 1.19–8.29) and
high-increasing (HR=4.52, 95%CI = 1.32–15.46) trajectories
were associated with retirement. UK participants with high and
low ERI were each classified into 3 trajectory classes respectively (no conditions, low-increasing, high-increasing), however
no significant associations with retirement were observed.
Conclusion Our findings demonstrate country differences in
mean ERI scores and trajectories of multimorbidities and their
association with retirement. Trajectories with high intercepts
indicating multimorbidity (i.e. 2+ chronic conditions at baseline) were associated with retirement in U.S. older adults only,
regardless of ERI. These results imply that baseline multimorbidity status may play a more important role than ERI on
retirement in those approaching the retirement age, however
further research is required. Socio-economic inequalities and
social policies may provide partial explanations for these findings. Public health and workplace interventions may be warranted for workers with multimorbidities.