Recent Advances in Compulsive Hoarding Research
At Hoarding Help Central, we understand the need for greater research into the causes, effects, and treatment of compulsive hoarding. With many new advances in compulsive hoarding research, we felt it would be valuable to include some of the progress made in the research of this disorder.
Today, we will be focusing on four main areas of compulsive hoarding research. This will include an overview of the controversy concerning the diagnostic status of hoarding, the key demographic factors associated with compulsive hoarding, neuropsychological correlations, and clinical treatment of compulsive hoarding.
At Hoarding Help Central, we believe that understanding the latest progress made in each of these areas is essential to forming a more informed comprehension of compulsive hoarding disorder. Let’s get started!

What is Compulsive Hoarding?
Before we look at each of the four main areas to see recent advancements in research concerning compulsive hoarding, it is crucial that you have an understanding of what compulsive hoarding is. By current standards, compulsive hoarding is defined as a psychological disorder. This psychological disorder is characterized by the presence of certain behaviors and compulsions. Most observable is the compulsion to collect excessively and save items that are of little to no perceived value to others. This compulsion results in a severely cluttered living space that results in significant distress and impairment.
There has been an increasing interest in researching the cause, effects, and treatment of compulsive hoarding in recent years. With this interest has come a wealth of new research that may prove beneficial in helping health professionals and loved ones better understand the compulsion to collect and save excessively. In this article, we will be highlighting some of the most debated issues surrounding compulsive hoarding as well as the most recent advancements in hoarding research.
The Diagnostic Status of Compulsive Hoarding
Perhaps the most highly debated issue regarding compulsive hoarding is diagnostic status. The uncertainty in establishing a diagnostic status of this disorder primarily stems from the appropriate classification of hoarding as a syndrome, extension of other disorders, or a disorder in itself. While you may not think that the classification of hoarding would cause any serious effects on further understanding the condition, classification plays an inherent role in further understanding of hoarding. The lack of clear classification of hoarding within the DSM has played a vital role in the underestimation of the burden brought on by the disease. A lack of a widely accepted classification of hoarding has also brought about consequences in inconsistencies in research. These factors, additionally, have led to challenges comparing the results of studies on hoarding and misconceptions regarding the proper treatment of this condition.
So how is hoarding classified in the current edition of the DSM? In the DSM-IV-TR, hoarding is described as a profound difficulty discarding of items. It is also listed as one of the eight diagnostic criteria used to describe obsessive-compulsive personality disorder. This is where the biggest debate surrounding the diagnostic status of compulsive hoarding is found. Many people believe that classifying hoarding behavior as a mere extension of obsessive-compulsive personality disorder is an incorrect classification of the behavior, as supported by recent evidence. In examining the criteria describing a challenge discarding of items as they relate to obsessive-compulsive personality disorder, evidence suggests that hoarding shouldn’t be attributed to obsessive-compulsive personality disorder any more than it is with other disorders.
Evidence to suggest that hoarding should not be classified as an extension of obsessive-compulsive personality disorder is also found in the fact that of all eight diagnostic criteria for obsessive-compulsive disorder, hoarding behavior has been found to have the lowest in terms of both specificity and predictive standards. These factors are fueling the argument that hoarding should be removed from the diagnostic criteria for obsessive-compulsive personality disorder and, rather, established as its own disorder.
Still, there is evidence showing that there is an observable link between obsessive-compulsive disorder and hoarding. One study, in particular, found that hoarders have a greater prevalence for certain obsessive-compulsive personality disorder traits such as miserliness and preoccupation with details. Other studies have reported that obsessive-compulsive disorder is more common in those that exhibit hoarding traits

The Epidemiology of Compulsive Hoarding
In addition to recent advancements in the diagnostic status of compulsive hoarding, there has also been measurable progress in the way of the epidemiology of compulsive hoarding. This includes progress in understanding both the prevalence and manifestation of compulsive hoarding in the general population. Up to this point, researchers have always estimated hoarding’s prevalence as a sub-portion of individuals with obsessive-compulsive disorder. With new research, this is beginning to change.
It is thought that much of the reason that compulsive hoarding has always been considered a sub-portion of the general population suffering from obsessive-compulsive disorder is because of a focus on unscientific evidence and small sample sizes. A real change in this fact has been witnessed recently with recent epidemiological studies suggesting that the prevalence of compulsive hoarding is much more widespread and burdensome than originally thought. Particular evidence of this fact is found in research data from the Baltimore Epidemiologic Catchment Follow-Up survey. In this data, it was found that, interestingly, 5 percent of the population experiences hoarding that is of clinically significant standards.
In yet another example of new data suggesting a higher rate of prevalence than previously thought in regards to compulsive hoarding, data from the National Comorbidity Survey Replication indicates that compulsive hoarding’s lifetime prevalence is as high as nearly 14 percent. Each of these studies made estimates based on reports of challenges discarding of items. It is also important to note that these studies did not target excessive acquisition of items nor did it focus on clutter. For this reason, it is not currently known whether or not these cases actually met diagnostic criteria as set by Hart and Frost.
In some of the new epidemiological findings presented in the lastest compulsive hoarding research, it has been stated that a large number of individuals exhibiting hoarding behavior report having at least one first-degree relative who also experiences challenges with hoarding. This suggests that there may be a stronger genetic link associated with the formation of hoarding behavior than previously thought.
Pursuing greater knowledge concern genetic links in those with compulsive hoarding disorder, other studies completed on persons with obsessive-compulsive disorder have made new observations. This includes the suggestion that probands of individuals exhibiting the symptoms of hoarding are four times more likely to experience a slew of hoarding symptoms as compared to probands of individuals who did not report hoarding symptoms. This evidence offers a new way to think about a possible genetic link in regards to hoarding behavior.
There is also recent data to suggest that the prevalence of hoarding also increases with age. In one study, it was reported that hoarding was nearly three times more prevalent in individuals aged 54 or older as compared to younger individuals aged 34 to 44 years old. These findings can likely be attributed to the fact that compulsive hoarding is both a progressive and chronic disorder. After all, there is much evidence to support this, found specifically in the fact that hoarding symptoms typically develop during the stages of childhood or adolescence only to become clinically significant in middle age.
Finally, clinical studies have also offered new evidence supporting the argument that hoarding behavior often co-occurs with a number of other psychological disorders. Most notably, in a study of a large clinical sample, nearly all individuals with a hoarding diagnosis also met the criteria for at least one other Axis 1 disorder. It should also be noted that these individuals possessed significantly more co-occuring disorders than individuals diagnosed with obsessive-compulsive disorder. Specifically, hoarders were noted to be significantly more likely than those with obsessive-compulsive disorder to also suffer from bipolar disorder, social anxiety disorder, and pathological grooming behavior.

Neuropsychological Research Into Compulsive Hoarding
Next, we’ll be taking a look at some of the latest advancements in neuropsychological research as it relates to compulsive hoarding. With neuropsychological research into hoarding not beginning until the last decade, there is a lot to unpack. In the last decade, two separate papers presented evidence to suggest that hoarding behavior is likely the result of frontal lobe lesions, creating dysfunction in the frontal lobe.
The first of these papers described the case of a 46-year-old man who exhibited abnormal collecting behavior after suffering a brain injury. This brain injury affected the left ventromedial prefrontal cortex and caudate. This injury also led to issues with judgment processes and social decisionmaking. In the second paper, a sample of 86 patients with focal lesions was examined for the presence of compulsive hoarding behavior. Of these 86 patients, a total of 13 exhibited unusual collecting behavior. When submitted to MRIs, all 13 of these subjects showed brain damage to the brain’s mesial frontal region, including both the anterior cingulate and right polar sector.
There has also been significant neuropsychological research into the observance of difficulty in making decisions with individuals suffering from compulsive hoarding. This is due in large to the fact that those suffering from compulsive hoarding behavior tend to see value in objects that others don’t view as important, as well as feeling significantly challenged in making decisions regarding the discarding of items of perceived value. Using self-report measures, these problems with decision-making has been observed in a large number of those suffering from compulsive hoarding. It should be noted, however, that laboratory studies have presented mixed results concerning decision-making deficits. This leaves this question, at present, unresolved.
Advances in Treatment for Compulsive Hoarding
Another area of compulsive hoarding research to witness significant progress in recent years is the area of treatment for compulsive hoarding. One promising study, in particular, is based around establishing the effectiveness of selective serotonin reuptake inhibitors in reducing hoarding symptoms in hoarders much in the way that it benefits those suffering from the symptoms of obsessive-compulsive disorder. This study is promising due to the fact that a measured improvement in the symptoms of hoarders has been observed in equivalency of those with obsessive-compulsive disorder. Still, the results of this study need to be qualified.
Due to the fact that changes are slow concerning the treatment of compulsive hoarding symptoms, researchers have begun examining alternate methods of delivery in efforts to improve the cost-effectiveness of treatment. In one study, researchers examined the effectiveness of group CBT. After 16 to 20 sessions as well as two home visits, patients exhibited a mean reduction of 8.6 points. This is less than that produced from individual treatment using the same treatment manual. This led researchers to alter their research procedures in order to increase effectiveness by screening participants more thoroughly and utilizing a more structured treatment manual for the group. After making these important changes, the mean reduction in the final group was observed to be 14.25, a measurable improvement. Although these studies offer a promising result in establishing an effective method of treatment for those suffering from compulsive hoarding, much still needs to be done to understand the best way to treat this disorder.