Smoking can increase pain severity in cancer patients

The relationship between smoking and cancer is well established. In a study published in the January 2011 issue of PAIN, researchers report evidence to suggest that cancer patients who continue to smoke despite their diagnosis experience greater pain than nonsmokers. They found that for a wide range of cancer types and for cancers in stages I to IV, smoking was associated with increased pain severity and the extent to which pain interfered with a patient's daily routine.

"To elucidate important relations between pain and smoking among persons with cancer, and to identify prospective targets for intervention, it is necessary to build upon past findings by examining smoking status and pain reporting in greater detail, across a wider range of cancer patients, and with regard to potential benefits of quitting smoking," commented lead investigator Joseph W. Ditre, PhD, Department of Psychology, Texas A&M University. "Specifically, we hypothesized that, among patients with diverse cancer diagnoses, current smokers would report greater pain, pain interference, and pain-related distress than former smokers and/or never smokers. We also planned to examine associations between pain and other smoking variables (e.g., number of years since quitting) in an exploratory fashion."

In this cross-sectional study, investigators surveyed 224 patients with a range of cancer diagnoses. Patients completed self-report measures of pain severity, pain-related distress, and pain-related interference, as well as a demographics questionnaire. Patients were asked to rate their perceived severity of bodily pain (1 = ''none" to 6 = ''very severe") and the degree to which pain interfered with their daily routine (1 = ''not at all" to 5 = ''extremely"). Current smokers experienced more severe pain than never smokers, and also reported more interference from pain than either never smokers or former smokers. Among former smokers, there was an inverse relation between pain and the number of years since quitting, suggesting that quitting smoking may reduce pain over time.

"Clinicians must do more to assist cancer patients to quit smoking after their diagnosis," according to Lori Bastian, MD, Durham VA Medical Center and Department of Internal Medicine, Duke University, writing in an accompanying commentary. While pointing out the complexities inherent in studies of the relationships among pain, cancer diagnoses, and nicotine addiction, she observed that "The major strength of this study is the diverse types of cancer and stage of disease." She continues, "Although more research is needed to understand the mechanisms that relate nicotine to pain, physicians should aggressively promote smoking cessation among cancer patients. Preliminary findings suggest that smoking cessation will improve the overall treatment response and quality of life."