Cigarette smoking increases the risk of a number of cancers (1
), and continued smoking after a cancer diagnosis has been linked with adverse outcomes for cancer patients, including treatment complications, diminished treatment efficacy, reduced overall survival, increased risk of second cancers, and poorer quality of life (QoL) (for reviews see (3
)). Unfortunately, a substantial number of people with smoking-related and non-smoking related cancers continue to smoke after their diagnosis. Estimates vary, with the highest rates reported for people with lung and head and neck cancers (with 24%– 60% smoking) (6
) and more modest rates among breast, prostate, and colorectal cancer survivors (7%–13% smoking (9
)). Population-based data suggest that approximately 20% of long-term cancer survivors smoke after their diagnosis (10
), with rates varying greatly by age and cancer site.
Smoking may also be a concern for family members who serve as informal caregivers while the cancer patient undergoes treatment. Smoking-related comorbidities such as cardiovascular disease and chronic obstructive pulmonary disease may comprise the health of family caregivers, diminishing their quality of life. In addition, smoking is linked with negative emotionality, depression, and history of psychiatric disorders in the general population (12
), suggesting that smoking caregivers may be a population at risk for poor mental health-related quality of life, especially in the context of increased stress associated with caregiving. Although one study of family members of patients with lung cancer found that symptoms of distress were actually associated with increased intentions to quit smoking (14
), findings from the general caregiving literature indicate that, compared with non-caregivers, caregivers are more likely to engage in unhealthy lifestyle behaviors (15
). This includes include greater frequency of smoking (16
), particularly if they are providing high-levels of care or experiencing high strain. This suggests that the stress and burden of caregiving might undermine smoking cessation efforts or that smoking may increase perceived stress and burden among caregivers. Research shows that cancer patients who smoke are likely to have family members who smoke (14
). One cessation trial recruiting smoking relatives of cancer patients reported that on average, cancer patients have two relatives who smoke (17
) and a recent study reported that 18% of family caregivers of women with lung cancer continued smoking after the diagnosis(18
It may be especially important to consider smoking in the context of dyads of cancer patients and their family caregivers. Continued smoking after a cancer diagnosis may be associated with guilt or blame about the cause of the cancer, particularly for cancers that are strongly associated with smoking, such as lung cancer. Patients and caregivers may experience increased distress after a cancer diagnosis if their loved one continues to smoke, particularly if they are not smoking, due to worry and increased recognition of the health risks for both partners(19
). If a cancer patient does quit smoking, continued smoking by family members may undermine the patients’ quit attempts (20
) and cause contentious interactions among family members. In a qualitative study of lung cancer patients, most of whom quit smoking after their diagnosis, Bottorff and colleagues (21
) found that many relationships with smoking family members were characterized by frequent stressful interactions regarding smoking and coercive attempts to get the family member to stop smoking. These types of negative interpersonal encounters would be expected to undermine social support and increase distress, thereby diminishing dyad members’ QoL. Despite the plausible mechanisms connecting cancer caregiver-patient smoking and QoL, few prior studies have examined whether the smoking of one dyad member is related to the QoL of both caregivers and their care recipients diagnosed with cancer. This study sought to build on the prior research by utilizing a large sample of cancer patients and caregivers recruited from multiple sites across the country that included patients with a cancer strongly associated with smoking (lung cancer) and one not commonly associated with smoking (colorectal cancer).
The first aim of the present study was to characterize patterns of smoking among recently diagnosed lung and colorectal cancer patients and their family caregivers, Second, we sought to characterize the context of smoking among lung and colorectal cancer caregivers by examining the association between caregiver smoking and psychosocial adjustment. As prior research has indicated that high-level or more intense caregiving is associated with more smoking among caregivers (16
), we hypothesized that smoking caregivers would report greater perceived caregiving burden and greater depression and anxiety. Finally, we examined the concordance of smoking between caregivers and cancer patients and concomitant associations with mental and physical QoL for both cancer patients and caregivers. Based on prior research indicating stronger associations between caregiving strain and emotional, rather than physical QoL(22
), we hypothesized that dyad members with discordant smoking status (one member smoked while the other did not) would report poorer mental health, but no difference in physical QoL.