Children who grow up with a parent addicted to drugs or alcohol are at increased risk of developing arthritis in adulthood, new research suggests.
An observational study of more than 13,000 adults showed that those with a history of parental addiction were roughly 30% more likely to have arthritis than their peers without such history after adjusting for relevant confounding factors.
"We believe that early adversities may change the way the child reacts to stress throughout their lives," Esme Fuller-Thomson, PhD, from the University of Toronto in Canada, told Medscape Medical News.
"Children growing up with addicted parents are often in very difficult home environments. Chronic stress in childhood can create long-term dysfunctions in the hypothalamus-pituitary-adrenal [HPA] axis, which is a key part of the body's stress response system. In turn, abnormal HPA axis functioning has been associated with arthritic symptoms," she explained.
The study was published online March 23 in the International Journal of Population Research.
Stand-Alone Risk Factor
The investigators analyzed data from the 2005 Canadian Community Health Survey on a representative sample of 13,036 adults.
After controlling for demographic characteristics, including age, sex, and race, adults with a history of parental drug or alcohol addiction had significantly higher odds of having arthritis relative to those without this history (odds ratio [OR], 1.58; 95% confidence interval [CI], 1.38 - 1.80).
Further adjustment for socioeconomic status, adult health behaviors, and mental health conditions had little impact on the parental addictions and arthritis relationship, the researchers say.
The association between parental addictions and arthritis was substantially reduced when adverse childhood experiences (OR, 1.33; 95% CI: 1.15 - 1.53) and all 4 groups of risk factors collectively (OR 1.30; 95% CI: 1.12 - 1.51) were included in the analyses; "however, the relationship remained statistically significant," the researchers write.
"We had anticipated that the adult offspring's health behaviors, such as smoking, obesity, and alcohol consumption, might explain the strong link between parental addictions and arthritis. However, we did not find this to be the case," study coauthor Jessica Liddycoat said in a statement.
"Even after adjusting for these adult health behaviors, as well as income, education, a history of childhood maltreatment, and mood and anxiety disorders, we found that parental addiction was still a statistically significant factor associated with 30% higher odds of arthritis," she added.
The researchers caution that the fact that the data derive from a survey makes it impossible to determine whether the relationship between parental addictions and arthritis is causal.
Worthy of Increased Attention
"This study is consistent with a growing number of studies finding associations between childhood psychosocial adversities and risks of developing chronic diseases in adulthood, but research in this area is in its infancy," Michael Von Korff, ScD, from Group Health Research Institute in Seattle, Washington, told Medscape Medical News.
Dr. Von Korff was not involved in the Toronto study but has done his own research on childhood psychosocial stressors and adult-onset arthritis, finding a similar link (von Korff et al, Pain. 2009;143:76-83).
"There are plausible biological and behavioral mechanisms that might contribute to such associations, but research on this topic to date does not provide a basis for anything more than speculation about causal mechanisms," said Dr. Von Korff.
"That said, the relationships between childhood psychosocial adversities and risks of chronic disease onset in adulthood deserve increased attention in prospective and records-based retrospective risk factor studies for conditions such as diabetes, heart disease, arthritis, and for chronic pain in general," he added.
The authors and Dr. Von Korff have disclosed no relevant financial relationships.
Int J Popul Res. Published online March 23, 2014. Full article