At the extreme end of the clutter spectrum are folks who suffer from what some call disposophobia —fear of disposing. In other words, they hoard. According to one report, nearly a million junkaholics suffer from this psychological, and the proof is in the piles. To help those who suffer from disposophobia, a national support group called Clutterers Anonymous models itself after the twelve-step format of Alcoholics Anonymous.
Source: wiktionary