female. Hoarding symptoms appear to be almost three times more prevalent in older
adults (ages 55–94 years) compared with younger adults (ages 34–44 years). 
Development and Course
Hoarding appears to begin early in life and spans well into the late stages. Hoarding symp-
toms may first emerge around ages 11–15 years, start interfering with the individual’s ev-
eryday functioning by the mid-20s, and cause clinically significant impairment by the
mid-30s. Participants in clinical research stud ies are usually in their 50s. Thus, the severity
of hoarding increases with each decade of lif e. Once symptoms begin, the course of hoard-
ing is often chronic, with few individuals reporting a waxing and waning course.
Pathological hoarding in children appears to be easily distin guished from develop-
mentally adaptive saving and collecting behaviors. Because children and adolescents
typically do not control their living environm ent and discarding behaviors, the possible
intervention of third parties (e.g., parents ke eping the spaces usable and thus reducing in-
terference) should be considered when making the diagnosis. 
Risk and Prognostic Factors 
Temperamental. Indecisiveness is a prominent featur e of individuals wi th hoarding dis-
order and their first-degree relatives.
Environmental. Individuals with hoarding disorder often retrospectively report stressful
and traumatic life events preceding the onset of the disorder or causing an exacerbation. 
Genetic and physiological. Hoarding behavior is familial,  with about 50% of individu-
als who hoard reporting having a relative who also hoards. Twin studies indicate that ap-
proximately 50% of the variability in hoarding behavior is attr ibutable to additive genetic
factors.