Rachel Aaron has spent years watching a puzzle unfold in her chronic pain patients: why do some people with the same injury end up struggling far more than others? A landmark two-year study she led at Johns Hopkins Medicine, published in Health Psychology, now offers one of the clearest answers yet — and it has less to do with the body than the heart. The research, spanning 1,453 adults living with chronic pain across the United States, found that people who struggle to identify and describe their emotions develop greater disruption to daily life from pain over time. The culprit, the researchers discovered, is psychological distress: anxiety and depression that builds up when someone can't make sense of what they're feeling. The study tracked participants over two years, surveying them on alexithymia — a trait marked by difficulty recognizing and expressing emotions — as well as pain severity, pain interference, and psychological well-being. Patients who started with higher alexithymia were more likely to develop significant psychological distress one year later. That distress, in turn, predicted greater pain interference at the two-year mark, meaning pain had a larger impact on their ability to work, sleep, and engage with the people around them. Crucially, the study found the reverse wasn't true — pain interference did not predict later increases in alexithymia. This confirmed that emotional processing difficulties are a risk factor for worsening pain outcomes, not simply a consequence of living with chronic pain.