Association between employment status and long-term changes in psychological stress across the COVID-19 pandemic period in Japan: NIPPON DATA2010.

Objectives: There is a growing interest in understanding the long-term impact of employment status on psychological stress. We aimed to explore the association between socioeconomic status and psychological stress over a long-term follow-up period across the COVID-19 pandemic, employing the Kessler 6-Item Psychological Distress Scale (K6).

Methods: We evaluated K6 scores from the 2021 follow-up survey of NIPPON DATA2010 using a self-administered questionnaire. The association between employment status and changes in K6 scores over 11 years was examined. Multiple regression analyses were used to estimate both crude and adjusted differences in K6 score changes across various socioeconomic factors including employment category, annual household income, marital status, and household size. Analyses were stratified by age, gender, and prefectural population size.

Results: This study included 1532 participants with an average age of 54.9 years. Over 11 years (2010-2021), participants in both gender and age groups showed increases in mean K6 scores (men: 2.79 to 3.06; women: 3.15 to 3.56; <65 years: 3.27 to 3.47; ≥65 years: 2.37 to 3.08). Nonemployed participants, particularly homemakers, showed significantly greater increases in K6 scores, compared with full-time employees, especially among women, younger individuals, and those in densely populated areas, with a significant interaction with age.

Conclusions: Nonemployed individuals, especially homemakers, experienced greater psychological stress over the past 11 years than did their fully employed counterparts. Public interventions, including strengthened social connections and telemental health services, may help mitigate these disparities, enhance mental well-being, and foster a sense of belonging.