Victims of domestic violence endure significantly higher health costs than other women for three years after the abuse ends, a new study finds. Abuse victims had health care costs that averaged more than $1,200 above non-abused women for the first two years after the abuse ended and about $400 above others in the third year. "Women may continue to experience physical and emotional consequences even years after their abuse ends, and that is reflected in their health care costs," said Amy Bonomi, co-author of the study and associate professor of human development and family science at Ohio State University. The study was led by Paul Fishman of the Group Health Research Institute in Seattle. The study appears online in the Journal of General Internal Medicine and will be published in a future print issue. The study is the first to look at how health care costs of abused women change from year to year after abuse ends. This study looked at costs during the years of abuse and then during each year up to 10 years later. The results suggest that domestic abuse acts on health care costs much like chronic health conditions, Bonomi said. "The prolonged impact of abuse on health care costs is consistent with what we find with people who quit smoking or abusing alcohol or drugs -- the costs don't go back to normal for years," she said. The study involved 2,026 women patients at Group Health Cooperative, a health system in the Pacific Northwest. All women in the study consented to giving researchers confidential access to their medical records. Women in the study were surveyed by telephone about whether they experienced any physical, sexual or psychological abuse from intimate partners, including husbands and boyfriends, since they were 18 years old. Women who indicated any abuse were asked which year each abuse type started and stopped. In all, 859 women reported some type of abuse in their adult lifetime and 1,167 reported no abuse. The researchers then looked at the women's health care costs through Group Health from 1992 through 2002. In order to make sure that it was the abuse that was driving the cost differences between abused and non-abused women, the study took into account a wide variety of factors that may also be related, including the women's age, race and ethnicity, education and income, marital and employment status, among other influences. Of those who reported abuse, about one-quarter said their abuse was "extremely severe," while about 39 percent said their abuse was "not severe" or "slightly severe." Overall, abused women's health care costs were $585 greater per year than non-abused women during the period of abuse. After the abuse ended, health costs were $1,231 higher in the first year, $1,204 higher the second year, and $444 higher the third year. By the fourth year after abuse, health care costs were similar to that of other women. Bonomi said the researchers don't have data to explain why health care costs are actually higher for the first two years after abuse ends than they were during the years of abuse. However, she believes she has one possible explanation. "Women may not be accessing health care services that they should be while they are with an abusive partner. They may fear retaliation, particularly if they are in a controlling relationship." In addition, women may be more likely to seek mental health services to help them cope once they are free from the abusive relationship. If anything, Bonomi said the study may underestimate the extra health care costs borne by victims of domestic abuse. Some victims participating in the study may not have admitted to being abused, so were not included among the abuse victims. Also, the study counts all types of abuse the same -- from severe physical and sexual abuse to controlling behavior that could qualify as psychological abuse. "Our findings are conservative; it is likely that the true health care costs for many abused women are higher than what we report," Bonomi said. Bonomi said the results show that abuse prevention efforts can actually save the health care industry significant amounts of money. "Victims of abuse require more health care resources for years after their abuse ends. If we can prevent domestic violence, we are not only helping the women involved, we are also saving money in our health care system." Other co-authors of the study included Melissa Anderson and Robert Reid of the Group Health Research Institute in Seattle; and Frederick Rivara of the Harborview Injury Prevention and Research Center at the University of Washington. The study was supported by grants from the federal Agency for Healthcare Research and Quality and the Group Health Foundation.