Source: MedScapeToday.com

February 24, 2012 (Palm Springs, California) — Cancer patients who smoke experience more severe symptoms than nonsmoking cancer patients and are also at greater risk of misusing opioids, a new study shows.

“Our findings show a profile of higher levels of physical symptoms (pain, fatigue, poor appetite, and insomnia) and psychological symptoms (depression and anxiety) among smokers than non-smokers,” report Diane Novy, PhD, from the Pain Management Center at the University of Texas MD Anderson Cancer Center in Houston, Texas, and colleagues.

The findings underscore the importance of smoking cessation for this patient population, she told Medscape Medical News, even though it’s unclear if there is a causal effect.

“We don’t know the cause. They may smoke more because of the pain,” she said in an interview. However, studies also show that smoking has been known to increase certain types of pain such as back pain, and nerve pain, she added. “If we can motivate them to stop smoking, I think they’re better off.”

The findings were presented here at the American Academy of Pain Medicine (AAPM) 28th Annual Meeting.

Pain, Fatigue, Insomnia

The study included 486 cancer patients (52% female), with a mean age of 55 years, who were referred to the Pain Management Center for uncontrolled pain. Ninety-four patients were smokers, and the rest (n = 356), classified as nonsmokers, were former smokers or never-smokers. The patients were diagnosed with a wide range of cancers, the most common being gastrointestinal (18.5%), followed by hematologic (15%) and head and neck cancer (14.6%).

The most common cancer among the smokers was head and neck cancer (22.3% vs 12.8% in nonsmokers), and the most common cancer in nonsmokers was gastrointestinal (19.9% vs 12.8% in smokers). Lung cancer was slightly less common among smokers than nonsmokers (10.6% vs 11.5%).

As part of their intake, patients completed the Edmonton Symptom Assessment Scale (ESAS) and the Screener and Opioid Assessment for Patients with Pain (SOAPP).

The ESAS showed that pain, fatigue, insomnia, appetite, depression, and anxiety were all statistically significantly worse in smokers than nonsmokers.

Specifically, on a scale of 0 (no symptoms) to 10, smokers reported the following:

  • a median pain level of 6.5 compared with 5 in nonsmokers (P < .001);
  • a median fatigue level of 8 compared with 7 in nonsmokers (P < .001);
  • a median depression level of 5 compared with 3 in nonsmokers (P < .001);
  • a median anxiety level of 6 compared with 3 in nonsmokers (P < .001);
  • a median level of 5 for poor appetite compared with 3 in nonsmokers (P = .023); and
  • a median insomnia level of 6 compared with 4 in nonsmokers (P = .026).

In addition, the SOAPP suggested that smokers were at greater risk for opioid misuse than were nonsmokers. Smokers reported more frequent mood swings than nonsmokers (26.6% vs 12.5%; P = .002) and were more likely to admit to occasional use of medication in a manner other than how it was prescribed (39.4% vs 19.6%; P < .001), occasional use of illegal drugs in the past 5 years (13.8% vs 2.6%; P < .001), and past legal problems or arrest (25.5% vs 8.2%; P < .001).

Further, among the smokers, 51% reported that they smoke within an hour of waking — an indication of higher risk for opioid misuse compared with smokers who delay their first cigarette.

Taken together, the findings point to the importance of extra caution when managing pain in cancer patients, said Dr. Novy.

“With cancer patients, opioids will always be the mainstay of treatment,” she said. With smokers, “we might change the route of delivery, so it might be a fentanyl patch that the patient can’t misuse, or it might be an opioid that does not have as much addiction potential like methadone, or maybe nerve blocks or other procedures.”

Smoking cessation should also be emphasized, she added. “When we work with patients and we’re able to say smokers seem to experience more pain and more of a symptom burden… for some patients it is an amazing wake-up call.”

On the basis of her results she suggests a clinical interview that explores a patient’s pain coping mechanisms and smoking triggers could help to inform treatment.

“For example, if expectation of analgesic benefit appeared to be an important smoking motivator, challenging these expectations and increasing coping self-efficacy would be reasonable treatment goals,” she reported.

If future studies confirm that smoking is associated with depression symptoms, treatment of depression would be appropriate.

Bi-Directional Interaction

The study by Dr. Novy and colleagues “makes an important contribution to a small, but rapidly growing scientific literature regarding complex and potentially bi-directional interactions between pain and smoking,” commented Joseph W. Ditre, PhD, a clinical psychologist at Texas A & M University in College Station.

“There is growing empirical and clinical interest in purported associations between tobacco smoking and the aggravation of cancer symptoms and treatment side effects, such as pain,” said Dr. Ditre, who recently published findings very similar to those of the current study.

“The current findings are highly consistent with the results of our 2011 study, which showed that continued smoking despite a cancer diagnosis was associated with greater pain severity and interference from pain,” he told Medscape Medical News.

“Some researchers have suggested that other factors (eg, depression) may be responsible for observed relations between smoking and increased pain,” he noted. “Thus, it would be interesting to know whether the current findings remain significant after accounting for sociodemographic, disease-specific, and psychiatric factors. Also, to get a better sense of whether continued smoking may increase pain and functional impairment in a causal fashion, future research should investigate longitudinal relations between continued smoking, smoking abstinence, and pain-related outcomes among persons with cancer.”

He said he agreed with Dr. Novy that smoking cessation should be emphasized in this population.

“Interestingly, our 2011 study showed a negative correlation between pain ratings and number of years since quitting smoking, suggesting that quitting smoking may confer benefit with respect to pain reporting,” he told Medscape Medical News. “Conversely, there is some question as to whether abstaining from smoking may increase pain in the short term (perhaps via removal of a preferred coping strategy, or via direct neurobiological processes).

“That said, smoking cessation is clearly indicated for persons with cancer, not just because smoking may increase pain, but because persistent smoking has been associated with impaired healing, reduced treatment efficacy, and increased risk for developing a second primary cancer,” Dr. Ditre added. “Thus, the advantages of quitting smoking likely greatly outweigh potential disadvantages, especially with respect to cancer-related outcomes.”

The study was supported by funding from the American Cancer Society and the National Institute on Drug Abuse. Dr. Novy has disclosed no relevant financial relationships. Dr. Ditre and his coauthors have disclosed no relevant financial relationships.

This news story was resourced by the Oral Cancer Foundation, and vetted for appropriateness and accuracy.