subsequent addictive influence of nicotine more than a decade later. Other forms of substance abuse, such as alcohol and addictive drugs, appear to have similar prenatal effects, altering gene expression to produce lasting functional and structural changes in the brain. For example, intergenerational transmission of susceptibility to morphine and cocaine addiction has been demonstrated in animal studies (Beitner-Johnston et al., 1992).
People who use any type of drug are likely to use others (Capaldi et al., 1996; Donovan and Jessor, 1985; Kandel and Yamaguchi, 1993), which suggests that the drugs may share common biological substrates and/or serve common functions. Specifically, there is evidence that substance abuse helps individuals cope with dysregulated serotonin by facilitating release and/or impeding reuptake of the neurotransmitter. Dysregulation of serotonin and of the dopamine system is also tied to adverse early environments in animal and human studies. A likely pathway to clusters of poor health habits, then, is suggested by genetic risk interacting with challenging prenatal or early childhood conditions to produce serotonergic dysregulation, which is then “treated” through multiple poor health habits (especially those involving addictive substances) that represent efforts at self-medication.
Prospects for modifying these behaviors have expanded in recent years. For example, “stage models” of behavior change provide important insights into the modification of risk factors for disease and the corresponding predisease pathways they implicate. When trying to change health behaviors, people go through a series of stages that influence their receptivity to different kinds of interventions. This observation laid the groundwork for matching the type of intervention to the stage of readiness to change. For example, individuals still considering whether to change a behavior (such as stopping smoking) are best approached through persuasive communications that highlight the benefits of change, whereas those already committed to change may be best served by interventions that induce them to make explicit commitments to change and that provide training for bridging the gap between intentions and action. Similarly, strategies of relapse prevention are best directed to those facing the problem of long-term maintenance. This matching approach has been successfully applied to smoking cessation, quitting cocaine, weight control, modification of a high-fat diet, adolescent delinquent behavior, practice of safe sex, condom use, sunscreen use, exercise, and obtaining regular mammograms (Prochaska, 1994; Prochaska et al., 1992).
A lesson learned from secondary prevention concerns modification of multiple behavioral risk factors simultaneously (such as diet, exercise, and stress management). The strategy is to identify effective ingredients from studies of single-risk-factor behavior change programs and combine them into packages of effective multibehavior change programs. For example,