Adult female survivors of domestic abuse were at least one-third more likely to develop cardiovascular disease, type 2 diabetes mellitus, and all-cause mortality over a short follow-up period, although they did not face a higher risk of hypertension, a new British study finds.
The study, published in the Journal of the American Heart Association, provides more evidence of a link between domestic abuse and poor health, even in younger women.
“The prevalence of domestic abuse is vast, so any increased risk in cardiometabolic disease may translate into a large burden of potentially preventable illness in society,” said study lead author Joht Singh Chandan, PhD, MBBS, of the University of Birmingham (England) and University of Warwick in Coventry, England, in an interview.
The researchers retrospectively tracked primary care patients in the United Kingdom from 1995-2017. They compared 18,547 adult female survivors of domestic abuse with a group of 72,231 other women who were matched to them at baseline by age, body mass index, smoking status, and a measure known as the Townsend deprivation score.
The average age of women in the groups was 37 years plus or minus 13 in the domestic abuse group and 37 years plus or minus 12 in the unexposed group. In both groups, 45% of women smoked; women in the domestic abuse group were more likely to drink excessively (10%), compared with those in the unexposed group (4%).
Researchers followed the women in the domestic abuse group for an average of 2 years and the unexposed group for 3 years. Those in the domestic abuse group were more likely to fall out of the study because they transferred to other medical practices.
Over the study period, 181 women in the domestic abuse group and 644 women in the unexposed group developed cardiovascular disease outcomes (adjusted incidence rate ratio, 1.31; 95% confidence interval, 1.11-1.55; P = .001). They were also more likely to develop type 2 diabetes (adjusted IRR, 1.51; 95% CI, 1.30-1.76; P less than .001) and all-cause mortality (adjusted IRR, 1.44; 95% CI, 1.24-1.67; P less than.001). But there was no increased risk of hypertension (adjusted IRR, 0.99; 95% CI, 0.88-1.12; P = 0.873).
Why might exposure to domestic abuse boost cardiovascular risk? “Although our study was not able to answer exactly why this relationship exists,Dr. Chandan said. “These can be broadly put into three categories: adoption of poor lifestyle behaviors due to difficult circumstances (physical inactivity, poor diet, disrupted sleep, substance misuse and smoking); associated development of mental ill health; and the alteration of the immune, metabolic, neuroendocrine, and autonomic nervous system due to the impact of stress on the body.”
It’s not clear why the risk of hypertension may be an outlier among cardiovascular outcomes, Dr. Chandan said. However, he pointed to a similar study whose results hinted that survivors of emotional abuse may be more susceptible to a negative impact on hypertension (Ann Epidemiol. 2012 Aug;22:562-7). The new study does not provide information about the type of abuse suffered by subjects.
Adrienne O’Neil, PhD, a family violence practitioner and cardiovascular epidemiologist at Deakin University in Geelong, Australia, said in an interview that the study is “a very useful contribution to the literature.” However, she cautioned that the study might have missed cases of domestic abuse because it relies on reports from primary care practitioners.
As for the findings, she said they’re surprising because of the divergence of major cardiovascular outcomes such as ischemic heart disease and stroke in groups of women with an average age of 37. “These differential health outcomes were observed over a 2-3 period. You probably wouldn’t expect to see a divergence in cardiovascular outcomes for 5-10 years in this age group.”
Dr. O’Neil said that, moving forward, the research can be helpful to understanding the rise of cardiovascular disease in women aged 35-54, especially in the United States. “The way we assess an individual’s risk of having a heart attack in the future is largely guided by evidence based on men. For a long time, this has neglected female-specific risk factors like polycystic ovary syndrome and hypertensive disorders of pregnancy but also conditions and exposures to which young women are especially vulnerable like depression, anxiety and [domestic abuse],” she said.
“This research is important as it gives us clues about who may be at elevated risk to help us guide prevention efforts. Equally, there is some evidence that chest pain presentation may be a useful predictor of domestic abuse victimization so there could be multiple lines of further inquiry.”
Dr. Chandan, the other study authors, and Dr. O’Neil reported no relevant disclosures.
SOURCE: Chandan JS et al. J Am Heart Assoc. 2020. doi: 10.1161/JAHA.119.014580.