Being impulsive could be linked to same genes as dozens of health conditions, new study shows

The urge for a quick reward is rooted deep in our DNA – and it could influence a wide range of health risks over our lives, a sweeping genetic study suggests.

Scientists have long known that impulsivity-related traits can be passed from parent to child, and that they are linked to mental and physical health. But the findings shed new light on the biological pathways driving this connection.

“Impulsive decision-making is something we all experience, but its biological roots have been surprisingly difficult to pin down,” said Sandra Sanchez-Roige, one of the study’s authors and an associate professor of psychiatry at the University of California San Diego in the United States.

Her team analysed genome-wide data from nearly 135,000 people who used 23andMe, the at-home DNA testing service.

The researchers identified 73 psychiatric, cognitive, and physical health traits that appear to be linked to a key mechanism of impulsive decision-making: delay discounting, which is the tendency to prioritise smaller, short-term rewards over bigger prospects in the future.

Those 73 traits include those linked to substance use, depression, executive function, chronic pain, heart health, obesity, immune system issues, and insomnia, according to the study, which was published in the journal Molecular Psychiatry.

Further analysis indicates that these links can be explained by “both overlapping and trait-specific biological processes,” the researchers said. Several of the genes were involved in dopamine signalling, brain structure, and metabolic pathways tied to neural growth and connections, for example.

To understand the real-world health consequences, the researchers created genetic risk scores for delay discounting, and then analysed health outcomes for more than 66,000 people. The scores were associated with 212 medical issues, including type 2 diabetes, chronic pain, and heart disease, the study found.

The findings indicate “delay discounting is measurable, highly heritable and relevant to many aspects of health,” including brain development, cognition, and physical wellbeing, Sanchez-Roige said in a statement.

The researchers said future studies should try to uncover whether genes linked to delay discounting actually cause other health issues, and test whether addressing environmental factors linked to impulsivity – such as educational attainment – could improve people’s health.

“By continuing to investigate this fundamental decision-making process, we may uncover new ways to prevent or treat a wide range of conditions,” Sanchez-Roige said.