People who develop OCD earlier in life are considered to have early-onset OCD, while those who develop OCD later are said to have late-onset OCD. Interestingly, there may be distinct differences in the symptoms, responses to treatment, overlapping illnesses, brain structure, and thinking patterns of people with early- versus late-onset OCD.
Gender Differences
One of the biggest differences between early-onset and late-onset OCD is the ratio of males to females. Studies have consistently found that males are much more likely to develop early-onset OCD than females. This gender difference seems to balance out among people who develop OCD later in life, with males and females being equally as likely to develop the disorder.
Severity of Symptoms and Response to Treatment
It has also been noted that the earlier OCD symptoms appear, the more severe they are. Some research suggests too that the earlier you develop OCD symptoms, the more difficult they can be to treat with both psychological and medical treatments. In other words, those with early-onset OCD may need to try more medications before finding relief from their symptoms and may need more trials of psychotherapy than people whose OCD begins later in life. However, a study that examined over 300 children with either early-onset OCD (before 10 years of age) and late-onset OCD (10 years of age or older) found that while there were differences in the symptoms between these two types of OCD, there was no difference in the children’s response to treatment. In other words, the age of the children in this particular study did not affect their response to cognitive-behavioral therapy that was tailored to their age, with or without medication. It looks like the jury is still out when it comes to treatment response and symptom severity in early-onset versus late-onset obsessive-compulsive disorder. More research is needed on the topic.
Development of Symptoms
Another difference is that people with early-onset OCD often have a gradual appearance of symptoms, whereas people who develop OCD later in life tend to have symptoms that come on quickly since they are usually tied to some sort of trigger, like a stressful life event such as the death of a loved one, loss of a job, or failing out of school. An exception to this rule is pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS), an autoimmune form of OCD that affects only children and in which symptoms appear very quickly.
OCD and Comorbid Illnesses
Obsessive-compulsive disorder often occurs with other illnesses, which are called comorbid illnesses. Some of the most common types of disorders that occur with OCD are major depressive disorder, ADHD, anxiety disorder, and oppositional defiant disorders. There is also a subtype of OCD called tic-related OCD which is more common in males and has an earlier age of onset.
Brain Differences
The brains of people with early-onset versus late-onset OCD may be different from one another as well. Studies have demonstrated that people with late-onset OCD have different patterns of neuropsychological deficits that those with early-onset OCD. It is not yet clear why this is the case and whether this has any impact on treatment.