Objective This study analyzes the association between job insecurity, measured by cumulative unemployment, and the risk of cardiovascular disease (CVD) among middle-aged workers with type 2 diabetes mellitus.

Methods We utilized data from the National Health Insurance Service of Korea, focusing on patients with type 2 diabetes, aged 40–50 who were continuously employed in 2009–2010. Job insecurity was defined by cumulative unemployment in 2012–2016 and categorized as stable, partially stable, or unstable. Participants were followed until December 2023, with incident CVD as the primary outcome. Cox regression models estimated sex-stratified hazard ratios (HR) with 95% confidence intervals (CI), with additional subgroup and sensitivity analyses.

Results Among 128 704 participants (107 071 males and 21 633 females; median age 51 years), CVD occurred among 6.1% of males and 3.9% of females. Job insecurity was associated with an increased risk of CVD [males: HR 1.12 (95% CI 1.05–1.19) for partially stable, HR 1.25 (95% CI 1.16–1.34) for unstable; females: HR 1.00 (95% CI 0.85–1.19) for partially stable, HR 1.33 (95% CI 1.13–1.57) for unstable]. Subgroup analyses showed particularly elevated risks among low-income males and high-income females. By age, males aged 40–49 in the partially stable and unstable groups had increased CVD risks, while those aged 50–59 had the highest risk in the unstable group. Among females, significant associations appeared only in the 40–49 age group.

Conclusions Among middle-aged workers with type 2 diabetes, prolonged job insecurity was significantly associated with an increased risk of CVD.

Key terms association; cardiovascular disease; cohort study; diabetes; economic impact; epidemiology; job insecurity; psychosocial stressor; type 2 diabetes; unemployment; work productivity; work stress

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