The CCSS has added substantially to the understanding of the health and health care of long-term survivors of childhood cancer. We have described a paradigm of cancer survivorship that is distinct from the traditional models of chronic disease.
80 Once cured of their primary disease, most children with cancer enjoy a period of relative health during their adolescent years, with morbidity only developing many years later. Many survivors have unhealthy lifestyles that can be expected to further contribute to their health risks as they age. Most survivors are not observed at a cancer center, are not receiving recommended risk-based health care or surveillance, are unaware of their risks, and are observed by health care providers who are, understandably, unfamiliar with this population. These factors should be considered when developing interventions aimed at encouraging healthy lifestyles and risk-based health care. illustrates some of the key relationships.
81Emmons et al
82 completed the first intervention study through CCSS that aimed to promote a healthy lifestyle (smoking cessation). The Partnership for Health study enrolled 796 participants from the CCSS cohort who identified themselves as smokers. The goals of the intervention were to address survivor-related factors associated with optimal health promotion, enhance self-efficacy and social support, increase knowledge about the health risks of smoking, reduce barriers to quitting, help participants set goals, and provide feedback regarding behavior change. Participants were randomly assigned to either a self-help intervention or a peer-counseling intervention. Self-help participants received a letter from the study physicians highlighting the importance of smoking cessation to reduce the risk of secondary cancers and a cessation manual. In the peer-counseling intervention, each survivor was assigned a trained childhood cancer survivor as a counselor. Up to six telephone calls were provided in a 7-month period, along with tailored and targeted materials and free nicotine replacement therapy. Follow-up assessments, including the primary outcome measure of smoking status, were conducted 8 and 12 months after the baseline survey for both groups of participants.
Results of the Partnership for Health study revealed that 15% of all participants had quit smoking at the initial 8-month follow-up. The smoking quit rate in the peer-counseling group was statistically significantly higher than in the self-help group at both the 8-month (17%
v 9%;
P < .01) and 12-month follow-up evaluations (15%
v 9%;
P < 0.01).
82 Controlling for baseline self-efficacy and depression, participants in the peer-counseling intervention group were twice as likely to quit smoking by the 12-month follow-up than those in the self-help group (odds ratio, 1.99; 95% CI, 1.27 to 3.14). The total cost of the intervention in the peer-delivered group was approximately $300 per participant compared with $1.25 in the control group. Thus a relatively low-intensity and low-cost intervention resulted in a high-impact behavioral modification, namely, smoking cessation. The Partnership for Health study also demonstrated the ability to successfully conduct a large-scale behavioral intervention study through the CCSS and serves as a model for future health behavior intervention studies.
To our knowledge, there are no published studies that promote risk-based care and surveillance among vulnerable childhood cancer survivors. The CCSS has designed three such studies that are aimed to promote breast cancer screening among women treated with chest irradiation, cardiovascular screening among survivors treated with cardiotoxic therapy, and skin protection and early skin cancer detection among survivors treated with irradiation. Pending external funding, we anticipate conducting these trials in the near future.
There is much more opportunity for study in this area. Over time, the CCSS has developed an infrastructure capable of supporting the rigorous testing of interventions, has an extensive track record of successful collaborations with independent investigators, and has served as a resource for numerous investigator-initiated, externally supported studies. With the current expansion of the CCSS to include long-term childhood cancer survivors diagnosed from 1987 to 1999, we will have access to a cohort of survivors whose ages span from childhood to the late 50s, with a diversity of race and ethnicity, geographical locale, socioeconomic strata, and interval from cancer diagnosis. There are few comparable resources that offer such an established infrastructure and a diverse cohort of survivors to allow the completion of adequately powered intervention trials aimed at encouraging healthy lifestyle behaviors and promoting risk-based health care.
As noted in the introduction of this special issue, the CCSS is an open resource available to investigators at non-CCSS institutions. We strongly encourage CCSS and non-CCSS investigators to collaborate with us in developing scientifically rigorous intervention studies. Potential topics of study include promoting a healthy diet (including adequate calcium intake) and physical activity and avoiding excessive alcohol consumption. These healthy habits, in addition to avoidance or cessation of smoking, can be targeted individually, or several habits can be targeted in the same intervention. Similarly, there is much opportunity to promote risk-based care and recommended screening and surveillance. This might include study of the transition of adolescent or young adult survivors from the treating institution to their primary care physician and the testing of a shared care model. Recognizing that most primary care physicians have only a few childhood cancer survivors in their practice, it is highly unlikely that traditional methods of continuing medical education will provide enough detail for primary care clinicians to follow their cancer survivors. Instead, study through the CCSS offers the opportunity to test various methods of providing patient-specific education to clinicians. Similarly, little attention has been given to integrating insurance companies or other health payors into the promotion of risk-based care among this population. When designing such trials, it is important to understand that these interventions will need to be delivered at a distance, because most adult survivors of childhood cancer are not being observed actively by their treating institution. However, this is also true of most cancer survivors in North America, and thus the interventions are more likely to be generalizable in comparison with high-intensity and controlled trials within single institutions. Finally, the CCSS has demonstrated that risky health behaviors and poor compliance with recommended medical and dental care are influenced frequently by social factors such as income and education. Similar risk factors prevail in the general population. Thus future interventions targeted at decreasing smoking or alcohol use, increasing levels of physical activity, or improving compliance with guidelines for risk-based care might be more effective if they address the conditions that lead to social disadvantage.
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