Phobias are perhaps the most directly related to procrastination and can result in task avoidance. Neuroticism has a curvilinear relationship to procrastination. Whether procrastination is a risk factor or symptom of these syndromes is hard to determine as most studies have been correlational so causality can't be determined. Procrastination may in fact be the beginning of a more serious disorder and can augment symptoms in vulnerable individuals. Often these patients put off treatment or have severe relapses.
Procrastination can also result from neurological damage or deficiencies.
A personality profile of the college student procrastinator, unpublished doctoral dissertation, University of Pittsburgh. Its role in transference and countertransference. An exploratory study of procrastination. Overcoming Procrastination . Procrastination and task avoidance .