Why women may be more likely to experience chronic pain than men

Chronic pain affects an estimated 28 million people in the UK and is reported more often by women. An early-stage animal study published in Science Immunology reports a hormonal and immune-cell difference that may help explain why pain can last longer in females.

Chronic pain is commonly defined as pain that lasts or recurs for more than three months, and it is reported more frequently by women. Researchers at Michigan State University published an early-stage animal study in Science Immunology linking sex hormones and immune-cell activity to differences in pain duration. The team observed that monocytes producing interleukin-10 were more active in male mice, and that blocking male sex hormones reduced those signals and raised pain sensitivity. The researchers reported they are exploring whether manipulating this immune pathway could shorten persistent pain without relying on opioids. Key findings: - Chronic pain is reported by an estimated 28 million people in the UK, with women making up the majority of cases. - An early-stage animal study found higher levels of interleukin-10–producing monocytes in male mice compared with females. - The study observed a link between male sex hormones and increased activity of these immune cells; reducing those hormones in male mice lowered interleukin-10 and increased pain sensitivity. - Authors said the results suggest pain resolution can be an active, immune-driven process and that they are investigating treatments that target this pathway. Summary: The study provides a biological explanation offered for sex differences in how long pain can persist, centred on hormone-regulated immune-cell activity. These results come from animal research and the investigators report further work is under way to assess whether targeting the pathway could affect pain duration in people; clinical relevance is undetermined at this time.