Elevated levels of hoarding in ADHD: A special link with inattention

Hoarding Disorder (HD) is under recognised and under-treated. Though HD develops by early adulthood, patients present only later in life, resulting in research based largely on samples of predominantly older females. Whilst formerly associated with Obsessive-Compulsive Disorder (OCD), it is now recognised that individuals with HD often have inattention symptoms reminiscent of Attention Deficit/Hyperactivity Disorder (ADHD). Here, we investigated HD in adults with ADHD. Patients in an ADHD clinic (n = 88) reported on ADHD, HD and OCD-related symptoms, and compared with age, gender and education matched controls (n = 90). Findings were assessed independently in an online UK sample to verify replication using a dimensional approach (n = 220). Clinically significant hoarding symptoms were found in similar to 20% versus 2% of ADHD and control groups, respectively, with those with hoarding being on average in their thirties and with approximately half being male. Greater hoarding severity was noted even in the remaining patients compared with controls (d = 0.89). Inattention was the only significant statistical predictor of hoarding severity in patients. Similarly, inattention, alongside depression and anxiety were the greatest predictors of hoarding in the independent sample where 3.2% identified as having clinically significant hoarding. Patients with ADHD had a high frequency of hoarding symptoms, which were specifically linked to inattention. HD should be routinely assessed in individuals with ADHD, as they do not typically disclose associated difficulties, despite these potentially leading to impaired everyday functioning. Research in HD should also investigate adults with ADHD, who are younger and with a greater prevalence of males than typical HD samples.

Automated summary

Research has found a high frequency of hoarding symptoms in patients with ADHD, with inattention being a significant predictor of hoarding severity. Despite the potential impact on everyday functioning, individuals with ADHD do not typically disclose associated difficulties, highlighting the importance of routine assessment for HD in this population. Further research on HD in younger adults with ADHD is needed, as they differ in demographics from typical HD samples.