Anna Nyberg, a postgraduate at the medical university Karolinska Institutet in Sweden, said her doctoral thesis is based on data from almost 20,000 employees in Sweden, Finland, Germany, Poland and Italy, working in a range of fields, such as the forest or hotel industries.
Nyberg and professor Tores Theorell of Stockholm University's Stress Research Institute compared levels of self-rated stress, health, sick leave and emotional exhaustion with how subjects perceived their managers' leadership in terms of certain positive and negative criteria, such as inspirational, supportive and good at delegating or authoritarian, dishonest and distant.
The researchers also looked at the effects of managerial leadership in relation to whether employees change jobs, quit due to poor health, or become unemployed.
The study found male residents of the Stockholm area ran a 25 percent greater risk of suffering myocardial infarction -- heart attack -- during the 10-year follow-up period if they had expressed displeasure with their managers at the start of the study. Moreover, the level of risk increased more sharply with time of employment for subjects that reported poorer leadership.
However, men and women who rated their managers as inspirational, positive and enthusiastic reported less short-term sick leave.