Can chronic fatigue syndrome cause an increase in anger and impulsiveness?

Yes. Chronic fatigue syndrome is often associated with overt or subtle depression. Depression, in turn, is often associated with anger and/or impulsiveness. That is why antidepressants are often helpful for treatment of Chronic Fatigue.

Unrelenting fatigue often conveys feelings of helplessness and loss, core components of depression, but the frustration can bring outbursts of anger and even agitation. Impulsive behavior could represent a "lashing out" due to desperation. This is not usually a simple problem to treat, and medication plus other programs may be needed. A virtual consult here at HT may help.