Smoking During Pregnancy Linked To Psychiatric Disorders In Children

The negative effects of nicotine addiction continue to emerge with study after study. Newly published research in the American Journal of Psychiatry found that women who smoke during pregnancy increased the risk of their offspring developing bipolar disorder (BD). BD is a psychiatric disorder characterized by significant shifts in mood that alternate between periods of mania and depression. The onset typically occurs in the late teens or early adulthood.

The researchers of the study examined data on over 700 women from a longitudinal study done at Kaiser Permanente from 1959-1966. When the researchers checked the status of the offspring of pregnant women who smoked during the Kaiser study, they discovered the women’s children had a twofold increased risk of developing BD.

Previous research has indicated that smoking during pregnancy can contribute to mental health problems following birth, including attention deficit hyperactivity disorder (ADHD), conduct disorder, oppositional defiant disorder, and substance abuse disorders. Not surprisingly, all of these disorders are strongly associated with one another. People with bipolar disorder are at one of the highest risks of developing addiction as compared to other disorders. Additionally, these disorders share clinical characteristics such as irritability, inattention, loss of self-control, and the inclination towards addiction. They can also be some of the most challenging conditions to treat in psychotherapy and mental health counseling, particularly with adolescents.

In 2012, a group of researchers found that maternal smoking during pregnancy significantly increased the development of conduct disorder in offspring. Conduct disorder can be one of the most serious forms of behavioral problems and is characterized by a marked increase of ongoing emotional and behavioral problems in children and teens. The behavioral problems typically include defiant and impulsive behavior, drug use, or criminal activity. Other research has suggested that women who smoke heavily while pregnant run a risk of having children who grow up to become repeat criminal offenders.

To test the theory that pregnant women who smoked increased the risk of their offspring developing conduct disorder, the researchers studied children raised by genetically related mothers and genetically unrelated mothers. To accomplish this, they looked at three longitudinal studies; 1) a longitudinal cohort study with biological and adopted children, 2) a longitudinal adoption-at-birth study, and 3) an adoption-at-conception study with genetically related families and genetically unrelated families. The researchers measured maternal smoking during pregnancy by the average number of cigarettes each pregnant woman smoked per day.

The results revealed that maternal smoking during pregnancy was associated with a significant risk of the offspring developing conduct problems. This was observed among children raised by genetically related mothers and genetically unrelated mothers.

Prenatal smoking also increases the unborn child’s chances of developing a variety of types of addiction, most notably alcohol, drugs, and nicotine dependence. Children of mothers who smoke during pregnancy have a significantly higher risk of becoming regular smokers in adolescence and adulthood.

The reason behind the association between prenatal smoking and psychiatric disorders in offspring most likely has something to do with the manner in which smoking affects nerve cells and alters the chemical makeup of the brain. Using brain imaging, researchers have found that patients addicted to nicotine have markedly decreased levels of the amino acid N-acetylaspartate in the anterior cingulate cortex. This is the area of the brain responsible for processing pleasure and pain. The more a person smokes, the lower these amino acid levels typically are.

Other research examining prenatal exposure to maternal cigarette smoking has found further aspects of affected brain development and behavior in adolescent offspring. A study recent study evaluated the involvement of the orbitofrontal cortex (OFC) in the relationship between prenatal smoking and substance use. The OFC is involved in the cognitive processing of decision-making. The researchers found that prenatal exposure to maternal cigarette smoking was associated with an increased likelihood of thinning of the OFC in adolescence and a significantly higher likelihood of substance abuse.

In terms of reducing the risks for health problems associated with smoking, the obvious solution is quitting. The data seems to suggest that there are a number of biological effects at play and that eliminating maternal smoking during pregnancy can significantly reduce the risk of the unborn child developing a number of psychiatric disorders and other associated problems in adulthood.

Sources:

Ardesheer Talati. Maternal Smoking During Pregnancy and Bipolar Disorder in Offspring. American Journal of Psychiatry, 2013; 170 (10): 1178 DOI: 10.1176/appi.ajp.2013.12121500. http://ajp.psychiatryonline.org/article.aspx?articleID=1746572

Gaysina D, Fergusson DM, Leve LD, et al. Maternal Smoking During Pregnancy and Offspring Conduct Problems: Evidence From 3 Independent Genetically Sensitive Research Designs. JAMA Psychiatry, 2013; DOI: 10.1001/jamapsychiatry.2013.127. http://archpsyc.jamanetwork.com/article.aspx?articleid=1716166

Lotfipour S, Ferguson E, Leonard G, Perron M, Pike B, Richer L, Séguin JR, Toro R, Veillette S, Pausova Z, Paus T. Orbitofrontal cortex and drug use during adolescence: role of prenatal exposure to maternal smoking and BDNF genotype. Archives of General Psychiatry, 2009 Nov;66(11):1244-52. doi: 10.1001/archgenpsychiatry.2009.124. http://archpsyc.jamanetwork.com/article.aspx?articleid=210420

Slotkin TA. Maternal Smoking and Conduct Disorder in the Offspring. JAMA Psychiatry, 2013; DOI: 10.1001/jamapsychiatry.2013.1951. http://archpsyc.jamanetwork.com/article.aspx?articleid=1716165