In conclusion, persistent insomnia may be a useful
predictor of HT in Japanese male workers. HT is a major
risk factor for cardiovascular diseases. On the other hand,
a recent prospective study55), as well as a meta-analysis
study56), suggested that insomnia might increase the risk
of cardiovascular diseases. The potential interaction
between insomnia and HT may lead to excessive
cardiovascular morbidity and mortality. In order to
implement effective measures to prevent cardiovascular
diseases, the three-way relationship between insomnia,
HT and cardiovascular diseases should be fully discussed
in future.