What Causes Addiction?

Alcoholism and other forms of addiction were once considered to be a problem of morality or weak will. Unfortunately, much of society still holds these archaic views despite increasingly overwhelming evidence that addiction is a complex, multifactorial disease including biological, psychological and sociological elements.

From a biological perspective, family, twin and adoption studies demonstrate that addiction has a biogenetic basis that is transmitted within families. The core of the predisposition is a set of genes that are responsible for the feeling of reward derived in the mesolimbic system of the brain. Individuals with an inherited hypodopaminergic functioning are more prone to seek substances or behavior that stimulate dopamine release and thus provide reward. Recognition of addiction as an inherited, reward deficiency disease provides a biological basis of understanding and helps to alleviate social stigma.

A positive family history of alcoholism elevates one's risk for alcohol abuse. Additionally, two distinct personality-related factors further enhance the risk. Firstly, proneness for social deviance or antisociality is directly associated with alcohol problems suggesting that addiction is a manifestation of a general difficulty in regulating behavior. This personality trait was significantly associated with a family history of alcoholism. Secondly, excitement/ pleasure-seeking was found to be a basic approach tendency that promoted increased drinking, which, in turn, leads to alcohol problems. However, it could also be argued that alcohol use can promote impulsive, excitement-seeking behavior. This raises the question of whether the expressions of such genetic traits are shaped by the environment.

The effect of environment on genetic expression has been examined. Genotype-environment correlations have been made to better understand the extent to which individuals are exposed to environments as a function of their genetic predispositions. Alcohol abuse was correlated with environments that activate or maintain the expression of the underlying genetic liability for alcoholism. Specifically, decreases in family moral-religious emphasis, family cohesion, and increased organization (strictness) were associated with pathological alcohol use.

While there is clearly a genetic predisposition, environmental factors seem to significantly affect the likelihood of the expression of the disease.

Without further elaboration, it becomes abundantly apparent that this is a complex topic, with a multitude of interacting variables as causative factors in the development and manifestation of addiction. It is a gross over simplification to state that addiction is caused by any one of the various factors. Appreciating the multifactorial aspect of the disease, it is clear that prevention and treatment approaches require a diverse and complementary range of individualized therapies.

Further study will continue to elucidate these and other interacting etiological factors. There is no one simple 'cause', any more than there is a simple isolated cause of other chronic, progressive, potentially fatal diseases such as breast cancer or adult onset (type II) diabetes. Similarly, it is absurd to ascribe issues of morality or will to any of these diseases. It is time for all of society, and government, to dismiss such archaic, stereotypical conceptions of addiction, and to shift our focus to solutions and away from shaming and blaming.