The etiology of Substance Disorders has at some level a spiritual, psychological, cultural, and biological cause. For all of these to be in play as a cause one must hold to substance dualism. That is, that human persons are body and mind(soul). John Feinberg(PHD Philosophy University of Chicago) describes substance dualism as material and immaterial. He writes.” “ Material things are extended and bounded things.... immaterial objects are consciousness or cognition. Human nature has traditionally been understood as a combination of a material thing and an immaterial substance.” So a adequate etiological theory would have to explain what happens to the material(Psychological and biological) and the immaterial(spiritual and the concept of culture). Not all are on a equal playing field as the evidence might show some are the “primary” cause where the others only“contribute" somewhat.
Culturally, the views of substance abuse or disorders can vary to a great degree, but there is some influence despite. Some of this influence comes from family. Parents play a big role and can have a grave impact on a child for good or bad. So culture has a moderate effect it seems.
Psychologically, the substance abuser may have feelings of self-worthlessness, which leads to sadness, then depression, then to some way to deal with that depression. To deal with it substance abuser will then, by free choice if chosen, cope with some sort of drink or drug. Then the brain’s balance is off because of how the abuser coped. Christian counselors Timothy E. Clinton and George W. Ohlschlager expand on what happens in this process writing , ”Brain chemistry is at the heart of what creates and sustains addiction. Addicts seek to either raise or lower their mood using complex (and sometimes criminal) rituals of self-medicating behavior…. In doing so, addicts will eventually train their brains to neurochemically “depend” on the substance or behavior.” So, to what effect do psychological factors play to the cause of substance disorder? Strong effects in seems.
Biologically, there are some twin studies that there are genetic factors to take into consideration, but this does not pre-determine one will become a substance abuser because of the dual nature of the human person. The material side may be prone, but the mind(soul) would not so much if one hold to at least a moderate-conservative orthodox Christian worldview. Biological contribution to the cause of substance disorders is mild at best and is not definitive as more studies are needed.
Finally, spiritual causes with the immaterial self in a human person falls in the area of sin. The Apolstle Paul in his letter to the Romans penning,
21So I find it to be a law that when I want to do right, evil lies close at hand. 22For I delight in the law of God, in my inner being, 23but I see in my members another law waging war against the law of my mind and making me captive to the law of sin that dwells in my members. 24Wretched man that I am! Who will deliver me from this body of death? 25Thanks be to God through Jesus Christ our Lord! So then, I myself serve the law of God with my mind, but with my flesh I serve the law of sin. 
If we takes Pauls word to be prima facie true(or at first sight) then the immaterial side or “mind” or “inner being” is part of the cause with the body or “flesh” as he puts it. They are in conjuction with one another, but the immaterial side is not the same as the flesh. So, in of itself is does contribute to the cause as that is where the “law of God, in my inner being” is in a struggle against the body. Also, sin is immaterial as well as thoughts of coping with a substance in a abusive way are immaterial Feinberg defined in a earlier paragraph.
I think the best treatment is situational to some degree, but these are the universals. 1. People need to seek God through prayer, fasting(Matthew 6), and Bible reading(2 Timothy 3:16-17). 2.Being involved with others (ideally who strggltue with substance disorder(s) to confess sins to begin the healing process(James 5:16) by bringing the darker side of ourselves into the light. This could be AA, Celebrate Recovery, New Life group, etc. The groups have to be structured to some degree to reap good fruit.
 John S. Feinberg, No One Like Him : The Doctrine of God, The foundations of evangelical theology (Wheaton, Ill.: Crossway Books, 2001), 214.
 “Attitudes toward substance-abuse problems can vary widely across various cultural groups.” David G. Benner and Peter C. Hill, Baker Encyclopedia of Psychology & Counseling, 2nd ed., Baker reference library (Grand Rapids, Mich.: Baker Books, 1999), 1178.
Apologetics study Bible gives a commentary on Exodus 20:5 saying “However, children suffer the consequences of their parents’ sinful choices. A parent’s adultery, substance abuse, manipulation or other dysfunctional behavior establishes a pattern that children model as they mature. The result can be a repetition of their parents’ emotional brokenness leading to conflict, divorce, poverty or other conditions that make their children’s, and even their grandchildren’s, lives difficult.
In this verse God suggests that one reason we should obey Him is for the sake of our children, grandchildren, and great-grandchildren. Like ripples spreading across a pool of calm water, our actions have consequences for generations to come. We can create waves of difficulty or blessing (v. 6), according to the choices we make. Ted Cabal, Chad Owen Brand, E. Ray Clendenen et al., The Apologetics Study Bible: Real Questions, Straight Answers, Stronger Faith (Nashville, TN: Holman Bible Publishers, 2007), 115.
 Timothy E. Clinton, George W. Ohlschlager and American Association of Christian Counselors, Caring for People God's Way (Nashville, Tenn.: Thomas Nelson, Inc., 2005-), 254.
 Baker Encyclopedia of Psychology says about genetic influence(biology), “ In addition to advances in the understanding of neurotransmitter actions involved in alcohol dependence, recent research has investigated the part genetics play in alcoholism. For years family, twin, and adoptive studies have suggested a role for genetics, environment, and choice in alcohol abuse. More recent twin studies have strengthened genetic involvement in the vulnerability to alcoholism. Alcohol dehydrogenase and aldehyde dehydrogenase are enzymes involved in the metabolism of ethanol in the body. Variants in genes responsible for these enzymes are associated with increased risk of alcoholism. In addition, genes involved in the synthesis and activity of the neurotransmitters serotonin and dopamine are thought to be associated with impulsive behavior and alcohol abuse. (Research suggests that impulsivity and alcoholism tend to occur together and run in families.) The data generated from genetic studies of alcoholism are equivocal at best; while suggestive, the precise effect these gene variants have on alcohol dependency is unknown.” David G. Benner and Peter C. Hill, Baker Encyclopedia of Psychology & Counseling, 2nd ed., Baker reference library (Grand Rapids, Mich.: Baker Books, 1999), 497.
 The Holy Bible : English Standard Version. (Wheaton: Standard Bible Society, 2001), Ro 7:21–25.
 Prima facie. (n.d.). Collins English Dictionary - Complete & Unabridged 10th Edition. Retrieved April 25, 2011, from Dictionary.com website: http://dictionary.reference.com/browse/Prima facie