Research published today from the world-leading Dunedin Multidisciplinary Health and Development Research Unit shows that maltreated children suffer the harmful physical and psychological health effects into adult life, long after the maltreatment ends.

The study, based at the University of Otago, has followed a group of 1000 children born in 1972/73 in Dunedin throughout their lives. Study members were most recently assessed at the age of 32, in 2004/05. Researchers compared adult inflammation levels to childhood maltreatment experienced by study members while they were growing up.

Inflammation, or swelling, is the body's natural response to stress. It helps to prevent the spread of infection and promote tissue repair after an injury. Inflammation is also a response to psychological stress, such as feeling threatened or frightened. However, the inflammatory response needs to be switched off quickly, especially if there is no actual physical harm. Otherwise, the inflammation itself has harmful effects, and what starts out as a natural defense ends up being a health risk. Increased inflammation in adults is predictor for adult diseases, such as heart disease and respiratory illnesses.

The researchers found that children suffering psychological maltreatment were twice as likely to show high adult inflammation levels as children who were not maltreated.

The research, published today in the leading American journal Proceedings of the National Academy of Science, has direct implications for modern medicine and public-health programmes. Since maltreated children have an increased risk for adult inflammation, they also have increased risk for adult disease and illness. Information about maltreatment experiences in early life could help to identify apparently healthy adults who have hidden risk for heart disease early enough to prevent it.

Preventing maltreatment of children could also reduce the prevalence, burden, and high cost of poor adult health. While prevention programmes are currently available, childhood maltreatment is still a dramatically widespread phenomenon worldwide.