Addiction is unlike most other disorders as the condition progresses and develops over time. For most sufferers, it starts out as an experimentation out of peer pressure or curiosity, while for some others it can be a coping mechanism to deal with stress, anxiety and sadness.
There are no specific causes for the disorder, only certain influencing factors. However, it is believed that different genetic & environmental factors are involved in the development process. According to research 1 , both genetic and environmental factors account for about 50% of the risk for addiction vulnerability each. “Genetic susceptibility together with early life experiences such as environmental factors contributes to the development of addiction,” explains a 2013 study 2 . Moreover, repeated exposure to large amounts of substances for prolonged periods of time can also make someone an addict, even if they have lower genetic susceptibility.
Common Causes Of Addiction
Here are some of the most common influencing factors that may increase addiction vulnerability and the risk of developing the disorder in someone:
Genetics 3 are regarded as one of the major influencing factors 4 in addiction. This means that if someone has a parent, sibling or a first-degree relative who is a substance or behavioral addict, then it is likely that they may become addicted as well as the disorder runs in families. “Addictions are moderately to highly heritable, which is paradoxical because these disorders require use; a choice that is itself modulated by both genes and environment,” states a 2005 study 5 . Twin and family studies 6 have shown that around 40% to 60% of the risk for this condition is associated with heritability. Another twin-family study of alcoholism in women revealed that the heritability of familial resemblance for alcoholism was about 51% to 59%. Moreover, genetic vulnerability was transferred equally from fathers and mothers to their daughters. According to research 7 on the genetics of substance dependence, “the most well-established genetic factors associated with alcohol dependence are in the genes encoding alcohol dehydrogenase (ADH), which oxidizes alcohol to acetaldehyde, and aldehyde dehydrogenase (ALDH2), which oxidizes acetaldehyde to acetate.”
Recent research 8 shows that genetics is associated with alcohol dependence & aerodigestive cancers, nicotine dependence & lung disease, cocaine dependence & psychiatric comorbidities related with substance use. According to a 2012 study 9 , 48% to 66% of alcohol dependence, 33% to 71% of nicotine dependence, 51% to 59% of cannabis use, 42% to 79% of cocaine use, 23% of opioid addiction, and 49% of disordered gambling is based on genetic factors. Researchers 10 also found that “Heritability is lowest for hallucinogens (0.39) and highest for cocaine (0.72).” A 2009 study 11 showed that according to twin, family and adoption studies the vulnerability and risk of each individual is directly associated with the degree and level of genetic relationship to an addicted family member. The researchers found that “in early adolescence the initiation and use of nicotine, alcohol, and cannabis are more strongly determined by familial and social factors.” However, during young and middle adulthood, such factors decline in importance and the influence of genetic factors take precedence. One 2008 study 12 specifically revealed that genetics become increasingly important during early and middle adulthood for nicotine, caffeine, alcohol and cannabis use.
Twin studies reveal that often both twins tend to be addicted due to similar & even identical genetics. In several instances, when one twin became addicted to a certain substance or behavior, the other twin was also found to be addicted, mostly to the same addictive substance 13 or behavior. Research is underway for identifying specific genes that are associated with addiction. The dopamine D2 receptors (DRD2 14 ) has been researched extensively for its role in the development of addictions. It has also been observed 15 that genetics are also involved in individual personality traits, like response to stress, reward-seeking and impulsivity. These can make someone more likely to experiment with substances. It can also increase the risk of continuous engagement or use, dependence and even relapse.
Certain environmental factors can also increase the risk of developing addiction. It refers to the people, environment, locations, events, experiences, stressors and risk factors a person is exposed to during their life that can influence their mindset. Environmental factors can reduce or enhance addiction vulnerability when it interacts with the genetic predisposition of the individual. According to a 2013 study. “Several types of environmental factors have been implicated in addiction, including psychosocial stresses, but by far the most powerful factor is exposure to a drug of abuse itself.” It has been observed that the following environmental aspects 16 may determine whether someone will become an addict or not:
A. Family environment
Home environment and parental supervision plays a crucial role, especially during adolescence and young adulthood. Children who grow up in dysfunctional or toxic families and experience frequent abuse, domestic violence, financial problems, adverse childhood experiences (ACEs), maltreatment, abandonment or neglect from parents or even lack of parental discipline & control may be more likely to become addicts. Moreover, single-parent status of families may influence substance use in teens and adolescents. According to a 2009 study 17 , “drug use among daughters living with single fathers significantly exceeded that of daughters living with single mothers, while gender of parents was not associated with sons’ usage.”
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B. Addicted parents
Children with parents 18 who are addicted to certain substances or behaviors are at risk of becoming addicts themselves. A 2015 study 19 states “parental substance abuse has been linked to ongoing behavioral problems, such as adolescent drug use,” in adolescents. Watching parents, older siblings, family members and other relatives abuse drugs or alcohol 20 , engage in criminal activity or negative behaviors can make children and adolescents prone to experimenting with drugs and alcohol. Moreover, some parents may even encourage their children to take drugs, but it is extremely rare.
Research 21 shows that one in 10 children live with at least one family member with substance use disorder (SUD) and most of these children are younger than 5 years of age. Families with an addicted parent are prone to experiencing emotional chaos, abuse, violence, conflict, fear, role reversal, loss and secrecy.
C. Peer pressure
Influence from friends, peers and acquaintances can leave a significant impact on teens and adolescents and encourage them to try out substances, alcohol or smoking. Friends who are addicted to substances or behaviors can persuade non-users to experiment and influence their judgment and decisions. Research 22 shows that apart from family processes, the impact of friends and peers influence the use and engagement in addictive substances and behavior in adolescents, making them vulnerable to health risks in adulthood. A 2010 study 23 found that “participants were most likely to take health risks when accompanied by someone they consider a friend.” Another study 24 revealed that the following aspects also influence the risk factors:
- The individual’s perception of the number of drug-using friends or peers
- The volume of information they obtain about substances from their friends
- The association between substance use and their perceptions
D. Availability and accessibility
The easy availability of substances in the community, neighborhood, home or school is another significant environmental risk factor that can lead to addiction. When an individual is repeatedly exposed to substances, alcohol or smoking, they feel encouraged to experiment and eventually become regular users. One 2016 study 25 revealed that “the availability of substances in the home during adolescence is associated with an earlier age at first substance use.” Moreover, living in a community engrossed by poverty and criminality can also be a contributing factor.
Neurobiology also plays a vital role in the development of addiction, when present along with genetic susceptibility and environmental risk factors. Chronic external stressors and trauma impact the brain’s physiology and increase vulnerability. Stress has been found to be strongly associated with addiction vulnerability and relapse. Studies 26 show that stress can rewire the physical structure of the brain due to certain neuroadaptive effects. This is done to incorporate the rise in cortisol release due to the stress. It can also affect a person’s prefrontal functioning causing reduced cognitive and behavioral regulation. Excessive stress caused by repeated substance use can also physiologically change the brain as well. Addiction is often caused as a result of this jeopardized neural state.
“Neurobiology and molecular genetics are contributing heavily to a new understanding of the causes of chemical dependence,” explains a 2008 study 27 . Moreover, addictive substances can adversely affect neurotransmitters like dopamine. As the neurotransmitters become compromised and become unable to function properly, tolerance develops, leading to addiction.
4. Mental disorders
Mental health conditions are often strongly associated 28 with addictions. Psychiatric disorders 29 , such as bipolar disorder, anxiety disorder and depression can increase the likelihood of an individual becoming addicted to alcohol, prescription drugs or other substances in an attempt to self-medicate. Individuals suffering from mental health problems, such as anxiety and depression may feel encouraged to look for an escape from their difficult emotions and can resort to drugs and alcohol. A 2010 study 30 states “Aggregate analyses demonstrated significant prospective risks posed by baseline mental disorders for the onset of nicotine, alcohol and illicit drug dependence with abuse over the follow-up period.”
Studies 31 also show that there are certain comorbid and co-occurring psychiatric disorders observed in people suffering from addictions. According to a 2017 study 32 on patients with co-occurring mental disorders in addiction treatment, it was found that “In the outpatient setting, the prevalence of comorbid diagnoses was considerably lower (4.6%) than in the inpatient setting (50.7%), but mood and anxiety disorders were the most prevalent additional diagnoses in both settings.”
It has been observed 33 that the male gender is more at risk of developing addiction than the female gender. Women are typically less likely to become addicted to substances and alcohol than men. However, one 2015 research 34 found that although men are more prone to suffering from substance use disorders, women are more susceptible to psychosocial and clinical effects of alcohol and some other substances. Moreover, women usually abuse drugs “at lower doses than do males,” found another 2007 study. It was also found that women have a higher risk of relapse after abstinence. “Addiction is characterized differently among women and men, and they begin using drugs for different reasons and motives,” states a 2016 study 35.
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Addiction is a debilitating condition but it can be treated effectively under the guidance of a medical professional. So if you or a loved one is suffering from this condition, make sure to consult a doctor and seek professional help immediately. With therapy and medication, one can overcome the symptoms and live a healthier and more stable life. Understanding the causes can help the doctor or therapist to devise a more accurate treatment plan for better and faster recovery.
- Nestler E. J. (2013). Cellular basis of memory for addiction. Dialogues in clinical neuroscience, 15(4), 431–443. https://doi.org/10.31887/DCNS.2013.15.4/enestler
- Vassoler, F. M., & Sadri-Vakili, G. (2014). Mechanisms of transgenerational inheritance of addictive-like behaviors. Neuroscience, 264, 198–206. https://doi.org/10.1016/j.neuroscience.2013.07.064
- Volkow, N. D., & Muenke, M. (2012). The genetics of addiction. Human genetics, 131(6), 773–777. https://doi.org/10.1007/s00439-012-1173-3
- Hiroi, N., Agatsuma, S. Genetic susceptibility to substance dependence. Mol Psychiatry 10, 336–344 (2005). https://doi.org/10.1038/sj.mp.4001622
- Goldman D, Oroszi G, Ducci F. The genetics of addictions: uncovering the genes. Nat Rev Genet. 2005 Jul;6(7):521-32. doi: 10.1038/nrg1635. PMID: 15995696.
- Mayfield, R. D., Harris, R. A., & Schuckit, M. A. (2008). Genetic factors influencing alcohol dependence. British journal of pharmacology, 154(2), 275–287. https://doi.org/10.1038/bjp.2008.88
- Wang JC, Kapoor M, Goate AM. The genetics of substance dependence. Annu Rev Genomics Hum Genet. 2012;13:241-61. doi: 10.1146/annurev-genom-090711-163844. Epub 2012 Jun 11. PMID: 22703173; PMCID: PMC3474605.
- Hartz, S. M., & Bierut, L. J. (2010). Genetics of addictions. Clinics in laboratory medicine, 30(4), 847–864. https://doi.org/10.1016/j.cll.2010.07.005
- Agrawal, A., Verweij, K. J., Gillespie, N. A., Heath, A. C., Lessov-Schlaggar, C. N., Martin, N. G., Nelson, E. C., Slutske, W. S., Whitfield, J. B., & Lynskey, M. T. (2012). The genetics of addiction-a translational perspective. Translational psychiatry, 2(7), e140. https://doi.org/10.1038/tp.2012.54
- Ducci, F., & Goldman, D. (2012). The genetic basis of addictive disorders. The Psychiatric clinics of North America, 35(2), 495–519. https://doi.org/10.1016/j.psc.2012.03.010
- Bevilacqua, L., & Goldman, D. (2009). Genes and addictions. Clinical pharmacology and therapeutics, 85(4), 359–361. https://doi.org/10.1038/clpt.2009.6
- Kendler KS, Schmitt E, Aggen SH, Prescott CA. Genetic and environmental influences on alcohol, caffeine, cannabis, and nicotine use from early adolescence to middle adulthood. Arch Gen Psychiatry. 2008 Jun;65(6):674-82. doi: 10.1001/archpsyc.65.6.674. PMID: 18519825; PMCID: PMC2844891.
- Gelernter, J., & Kranzler, H. R. (2010). Genetics of drug dependence. Dialogues in clinical neuroscience, 12(1), 77–84. https://doi.org/10.31887/DCNS.2010.12.1/jgelernter
- Thanos, P. K., Gopez, V., Delis, F., Michaelides, M., Grandy, D. K., Wang, G. J., Kunos, G., & Volkow, N. D. (2011). Upregulation of cannabinoid type 1 receptors in dopamine D2 receptor knockout mice is reversed by chronic forced ethanol consumption. Alcoholism, clinical and experimental research, 35(1), 19–27. https://doi.org/10.1111/j.1530-0277.2010.01318.x
- Kreek, M., Nielsen, D., Butelman, E. et al. Genetic influences on impulsivity, risk taking, stress responsivity and vulnerability to drug abuse and addiction. Nat Neurosci 8, 1450–1457 (2005). https://doi.org/10.1038/nn1583
- Drugs, brains, and behavior: The science of addiction. (2007). PsycEXTRA Dataset. https://doi.org/10.1037/e596722007-001
- Hemovich, V., & Crano, W. D. (2009). Family structure and adolescent drug use: an exploration of single-parent families. Substance use & misuse, 44(14), 2099–2113. https://doi.org/10.3109/10826080902858375
- Kilpatrick DG, Acierno R, Saunders B, Resnick HS, Best CL, Schnurr PP. Risk factors for adolescent substance abuse and dependence: data from a national sample. J Consult Clin Psychol. 2000 Feb;68(1):19-30. doi: 10.1037//0022-006x.68.1.19. PMID: 10710837.
- Calhoun, S., Conner, E., Miller, M., & Messina, N. (2015). Improving the outcomes of children affected by parental substance abuse: a review of randomized controlled trials. Substance abuse and rehabilitation, 6, 15–24. https://doi.org/10.2147/SAR.S46439
- Solis, J. M., Shadur, J. M., Burns, A. R., & Hussong, A. M. (2012). Understanding the diverse needs of children whose parents abuse substances. Current drug abuse reviews, 5(2), 135–147. https://doi.org/10.2174/1874473711205020135
- Lander, L., Howsare, J., & Byrne, M. (2013). The impact of substance use disorders on families and children: from theory to practice. Social work in public health, 28(3-4), 194–205. https://doi.org/10.1080/19371918.2013.759005
- Loke, A. Y., & Mak, Y. W. (2013). Family process and peer influences on substance use by adolescents. International journal of environmental research and public health, 10(9), 3868–3885. https://doi.org/10.3390/ijerph10093868
- Varela, A., & Pritchard, M. E. (2011). Peer influence: use of alcohol, tobacco, and prescription medications. Journal of American college health : J of ACH, 59(8), 751–756. https://doi.org/10.1080/07448481.2010.544346
- Pruitt BE, Kingery PM, Mirzaee E, Heuberger G, Hurley RS. Peer influence and drug use among adolescents in rural areas. J Drug Educ. 1991;21(1):1-11. doi: 10.2190/0LWT-23YL-TMP7-TC23. PMID: 2016660.
- Broman C. L. (2016). The Availability of Substances in Adolescence: Influences in Emerging Adulthood. Journal of child & adolescent substance abuse, 25(5), 487–495. https://doi.org/10.1080/1067828X.2015.1103346
- Sinha R. (2008). Chronic stress, drug use, and vulnerability to addiction. Annals of the New York Academy of Sciences, 1141, 105–130. https://doi.org/10.1196/annals.1441.030
- Erickson, C. K., & Wilcox, R. E. (2008). Neurobiological causes of addiction. Journal of Social Work Practice in the Addictions, 1(3), 7-22. https://doi.org/10.1300/j160v01n03_02
- Comorbidity: Addiction and other mental disorders. (2011). PsycEXTRA Dataset. https://doi.org/10.1037/e500132013-001
- Claro, H. G., de Oliveira, M. A., Bourdreaux, J. T., Fernandes, I. F., Pinho, P. H., & Tarifa, R. R. (2015). Drug use, mental health and problems related to crime and violence: cross-sectional study. Revista latino-americana de enfermagem, 23(6), 1173–1180. https://doi.org/10.1590/0104-1169.0478.2663
- Swendsen, J., Conway, K. P., Degenhardt, L., Glantz, M., Jin, R., Merikangas, K. R., Sampson, N., & Kessler, R. C. (2010). Mental disorders as risk factors for substance use, abuse and dependence: results from the 10-year follow-up of the National Comorbidity Survey. Addiction (Abingdon, England), 105(6), 1117–1128. https://doi.org/10.1111/j.1360-0443.2010.02902.x
- Hartwell, K. J., Tolliver, B. K., & Brady, K. T. (2009). Biologic Commonalities between Mental Illness and Addiction. Primary psychiatry, 16(8), 33–39.
- Dauber, H., Braun, B., Pfeiffer-Gerschel, T., Kraus, L., & Pogarell, O. (2018). Co-occurring Mental Disorders in Substance Abuse Treatment: the Current Health Care Situation in Germany. International journal of mental health and addiction, 16(1), 66–80. https://doi.org/10.1007/s11469-017-9784-5
- Ceylan-Isik, A. F., McBride, S. M., & Ren, J. (2010). Sex difference in alcoholism: who is at a greater risk for development of alcoholic complication?. Life sciences, 87(5-6), 133–138. https://doi.org/10.1016/j.lfs.2010.06.002
- Polak, K., Haug, N. A., Drachenberg, H. E., & Svikis, D. S. (2015). Gender Considerations in Addiction: Implications for Treatment. Current treatment options in psychiatry, 2(3), 326–338. https://doi.org/10.1007/s40501-015-0054-5
- Zolala, F., Mahdavian, M., Haghdoost, A. A., & Karamouzian, M. (2016). Pathways to Addiction: A Gender-Based Study on Drug Use in a Triangular Clinic and Drop-in Center, Kerman, Iran. International journal of high risk behaviors & addiction, 5(2), e22320. https://doi.org/10.5812/ijhrba.22320