Adhering to Recommended Lifestyle Changes and Medications 9 Months to 3 Years after Hematopoietic Stem Cell Transplant: Self-Reported Adherence and the Practical, Psychological, and Social Correlates of Adherence

Survivors of hematopoietic stem cell transplantation (SCT) must adhere to various lifestyle changes and medication regimens to protect their health and recovery, often for an extended time. Little evidence describes adherence after SCT or correlates of adherence, although evidence from other populations strongly suggests that adherence will be suboptimal for many survivors. To explore these research questions, we conducted secondary analyses on self-reported data from 255 survivors participating in a larger intervention trial. All had undergone stem cell transplant (SCT) (55% autologous, 45% allogeneic) 9 months to 3 years prior to enrollment for a hematologic cancer. After completing baseline measures, they were randomized to one of 4 study arms that varied the writing instructions they were provided as they completed 4 brief writing assignments (1 per week over 4 weeks) in which they wrote about their SCT experience. The 2x2 factorial design crossed whether they used evidence-based instructions for emotionally expressive writing (yes/no) and whether they were told their writing was to be shared with other patients as a form of peer support (yes/no). Writing instructions were not associated with outcomes in the present analyses and are not further described (see Rini et al, 2014). Participants completed a follow-up assessment 3 weeks after the intervention. Collapsing across study arms, we examined participants' self-reports about whether their medical team currently recommended changes to their diet and social activities (e.g., avoiding crowds or ill people), and whether they were currently supposed to be taking medications related to their SCT; because this was not a primary goal of the research, we did not assess what medications they were prescribed. Survivors who reported a recommendation to engage in each behavior also reported the extent to which they were following recommendations on a scale from 1=not at all to 5=completely. A substantial minority of participants reported that their medical team currently recommended changes to their diet (14.2%) and social activities (18.3%), and that they needed to take SCT-related medications (46.5%). Participants who had undergone SCT more recently (fewer weeks since SCT) were more likely to report recommendations to change their social activities (r = -.18, p = .005). Also, compared to autologous SCT survivors, allogeneic SCT survivors were more likely to report recommendations to change their diet (p = .03) and social activities (p = .004), and the need to take medications (p < .001). Only 55.2% of participants who reported being informed of the need to make dietary changes said they were quite a bit or completely adherent (4 or 5 on the response scale). A greater, but still suboptimal, proportion (74.0%) were quite a bit or completely adherent with recommended social activity changes, and 95.8% were quite a bit or completely adherent with medication use (83.9% completely and 11.9% quite a bit). Depending on the medication in question and survivors' definition of being completely versus quite a bit adherent, these findings may indicate cause for concern. Research on solid organ transplant suggests that even small deviations from recommended dosages can influence graft loss or rejection (Dobbels et al., 2010). With respect to correlates of adherence, better physical functioning (SF-36 physical component scores; r = -.33, p = .04) was associated with lower adherence with dietary changes. For social activity changes, having a higher quality relationship with a partner and having more years of education were associated with greater adherence (r = .41, p = .02, and r = .40, p = .01, respectively) whereas having children was associated with lower adherence (r = -.31, p = .03). For medications, better physical functioning was associated with lower adherence (r=-.19, p =.045). Findings suggest that practical, psychological, and social factors may influence adherence to important lifestyle and medication regimens after SCT. They also provide a rationale for larger scale studies using rigorous measures. Using digital platforms/devices to track adherence would provide needed rigor while enabling development of digital coaching interventions to promote sustained behavior change. In the era of consumerization of medicine, it is important to provide evidence to patients that consumerization also means sustained self-engagement to optimize their outcome.