Depression

• A particularly common cause of pathological gambling is depression. This cause is seen more often in women than in men. The pathological gambler uses gambling as a way to escape, or "zone out," his feelings of depression.
  
  

AD/HD

• Attention-deficit/hyperactivity disorder is a fairly prevalent cause of pathological gambling, particularly in those who're seeking the thrill or the high of gambling more than the money. According to the Encyclopedia of Mental Disorders, some research has found that men who've been diagnosed with pathological gambling disorder were more likely to have been diagnosed with AD/HD in childhood than men in the general population.
  
  

Cognitive Distortions

• People suffering from pathological gambling disorder often have skewed insight when it comes to finances. They believe that their sole problem is money while at the same time believing that money is the solution to their problems, thus seeking the "big win" to repair their financial situation.
  
  

Heredity

• It's also theorized that pathological gambling may have a hereditary component to it, much like alcoholism. The more impulsive a person's family is, the more impulsive she's likely to be. This is a significant contributing factor in pathological gambling behavior.
  
  

Personality Disorders

• Pathological gambling is sometimes seen in conjunction with personality disorders, particularly antisocial personality disorder. This is thought to be due to the impulsivity aspect of antisocial personality disorder and the immediate gratification sought in pathological gambling.
  
  

Summary

• There are numerous causes of pathological gambling. However, it seems to be consistently thought that pathological gambling isn't a disease in and of itself, but a symptom of a larger or more complex mental process.