Prolonged or serious conflicts at work and incident dementia: a 23-year follow-up of the Copenhagen City Heart Study

PURPOSE: Only a few studies have investigated the impact of negative aspects of social relations on cognitive function, and they have shown mixed results. Conflicts at work are part of the negative aspects of social relations, but the impact of experiencing conflicts at work has not yet been investigated as a risk factor for dementia. Therefore, we investigated whether experiencing prolonged or serious conflicts with a supervisor or colleagues at work was associated with incident dementia in old age. METHODS: We analyzed data of 6,436 men and women from the third survey of the Copenhagen City Heart Study. At baseline in 1991–1994, the participants reported whether they had ever had a prolonged or serious conflict at work. The participants were followed until 2014. We used Poisson regression to estimate incidence rate ratios (IRR) and their 95% confidence intervals (CI). RESULTS: After adjusting for potential confounders, the IRR for dementia was 1.53 (95% CI 0.77–3.03) among participants who had reported having prolonged or serious conflicts both with a supervisor and colleagues compared with participants who had never had such conflicts. In separate analyses stratified by sex, the IRRs were 2.14 (95% Cl 0.97–4.71) for men and 0.98 (95% Cl 0.29–3.32) for women. CONCLUSIONS: Our findings did not support an overall association between experiencing prolonged or serious conflicts at work and incident dementia. However, because of the large differences in the point estimates for men and women, future research could aim at investigating potential sex differences regarding the association between conflicts at work and dementia.