How Does Impulsivity Relate to Different Mental Health Conditions?

What you need to know

• Impulsive decision-making was associated with symptoms of tobacco use, cannabis use, and depression when examining multiple mental health conditions together
• Impulsivity showed some broad connections to substance use and other psychiatric symptoms, but was not universally linked to all conditions studied
• The relationship between impulsivity and mental health may be more complex than previously thought

Understanding impulsivity and mental health

Have you ever wondered why some people seem more prone to making impulsive decisions, while others are better able to delay gratification and think through the long-term consequences of their choices? This tendency, known as delay discounting, is a form of impulsivity that researchers are very interested in studying. Delay discounting refers to how much a person prefers smaller, immediate rewards over larger rewards that come after a delay.

For example, if given the choice between receiving $30 today or $80 in 30 days, someone with high delay discounting (high impulsivity) would be more likely to choose the immediate $30. On the other hand, someone with low delay discounting would be more willing to wait for the larger delayed reward.

Understanding delay discounting is important because previous research has found links between higher levels of this type of impulsivity and various mental health conditions, including substance use disorders, depression, anxiety, and attention-deficit/hyperactivity disorder (ADHD). This has led some researchers to propose that delay discounting could be a “transdiagnostic” indicator - meaning it may be a common factor underlying multiple different psychiatric disorders.

However, most studies on this topic have only looked at delay discounting in relation to one condition at a time. This makes it difficult to know if the links to impulsivity are truly specific to each disorder, or if they might be explained by overlap between conditions. For instance, many people with depression also experience anxiety, so a study finding higher impulsivity in depression may actually be picking up on the anxiety component.

To address this issue, a team of researchers conducted a large study examining delay discounting and symptoms of multiple psychiatric conditions simultaneously in over 1,300 adults from the general community. Their goal was to get a clearer picture of how impulsivity relates to different aspects of mental health when accounting for the connections between various symptoms and disorders.

How the study worked

The researchers recruited 1,388 adults from the community to complete an in-person assessment. Participants answered questionnaires about symptoms of several common mental health conditions:

• Alcohol use disorder
• Tobacco use disorder
• Cannabis use disorder
• Other drug use disorders
• Depression
• Anxiety
• Post-traumatic stress disorder (PTSD)
• Attention-deficit/hyperactivity disorder (ADHD)

They also completed a delay discounting task where they made choices between smaller immediate rewards and larger delayed rewards. This allowed the researchers to calculate a measure of each person’s level of impulsivity.

The study then used several statistical approaches to look at how delay discounting related to symptoms of the different conditions:

1. They compared impulsivity levels between people who scored above clinical cutoffs for each disorder and those who did not.

2. They used a technique called principal components analysis to identify patterns of overlap between the different psychiatric symptoms. This resulted in two main components - one reflecting substance use symptoms and another reflecting other mental health symptoms. They then examined how delay discounting related to these two broader patterns.

3. Finally, they used a complex statistical model to look at how delay discounting uniquely related to each specific condition while accounting for all the others simultaneously.

Key findings on impulsivity and mental health

When looking at each condition separately, the researchers found that people who screened positive for tobacco use disorder, cannabis use disorder, other drug use disorders, depression, PTSD, anxiety, and ADHD all showed higher levels of delay discounting compared to those who screened negative. However, there was no significant difference for alcohol use disorder.

The principal components analysis revealed that delay discounting was associated with both the substance use component and the other mental health component. This suggests some broad connections between impulsivity and psychiatric symptoms.

However, the most complex analysis examining all conditions together painted a more nuanced picture. In this model, delay discounting showed unique significant associations with only tobacco use, cannabis use, and depression symptoms. The links to other drug use, anxiety, PTSD, and ADHD were no longer significant when accounting for these other relationships.

What do these results mean?

The findings provide some support for delay discounting as a transdiagnostic indicator that may be relevant across multiple psychiatric conditions. However, they also suggest the relationship between impulsivity and mental health is more complex than it might appear when looking at disorders in isolation.

The consistent links found for tobacco use are not surprising. Smoking provides small, immediate rewards (the effects of nicotine) at the cost of larger, delayed consequences (health effects). So the act of smoking itself mirrors the decision-making pattern seen in delay discounting.

The association with cannabis use is interesting, as previous research has been mixed on whether cannabis users show higher impulsivity. This study suggests there may be a unique relationship when accounting for other substance use and mental health symptoms.

For depression, higher delay discounting could potentially relate to feelings of hopelessness about the future, leading to a greater focus on immediate rewards. However, it’s important to note that the study design can’t determine if impulsivity is a cause or consequence of depressive symptoms.

The lack of association with alcohol use disorder was unexpected based on previous research. It’s possible this reflects differences between the general community sample in this study versus clinical samples of people with severe alcohol problems examined in other research.

Limitations and future directions

While this study provides valuable new insights, there are some important limitations to keep in mind:

• The study used screening questionnaires rather than full diagnostic interviews, so participants weren’t necessarily diagnosed with clinical disorders.

• It was a cross-sectional study looking at symptoms and impulsivity at one point in time. This means we can’t draw conclusions about whether impulsivity leads to psychiatric symptoms, or vice versa.

• The study didn’t examine all possible mental health conditions. Future research should look at a wider range of disorders.

• The community sample had relatively low levels of psychiatric symptoms compared to what might be seen in clinical populations. The relationships between impulsivity and mental health could look different in people with more severe symptoms.

Moving forward, more research is needed to clarify the role of delay discounting across different psychiatric conditions. Studies that follow people over time could help determine if impulsivity predicts the development of mental health symptoms. It would also be valuable to examine whether treatments that reduce impulsivity lead to improvements across multiple disorders.

Additionally, delay discounting likely reflects multiple underlying brain processes. Future studies could use neuroimaging and other methods to tease apart different mechanisms that may link impulsivity to various aspects of mental health.

Conclusions

• Impulsive decision-making shows some broad connections to both substance use and other psychiatric symptoms
• However, when examining multiple conditions together, unique associations were only found for tobacco use, cannabis use, and depression
• The relationship between impulsivity and mental health appears more nuanced than suggested by studies looking at single disorders in isolation
• More research is needed to clarify how delay discounting relates to different psychiatric conditions and whether it could be a useful transdiagnostic indicator

This study highlights the complexity of mental health and the importance of examining multiple symptoms and conditions together. While impulsivity may play a role across various psychiatric disorders, its significance likely varies depending on the specific symptoms and behaviors involved. Understanding these nuanced relationships can ultimately lead to better assessment and treatment approaches for mental health conditions.