Table 1.

Selected characteristics and risk of death for patients with cancer who had eligible postdiagnosis information on smoking status, by smoking status before and after cancer diagnosis, The Shanghai Cohort Study 1986–2010

No. of casesNo. of deaths (%)Person-years at riskaAverage person-yearsaMedian survival (y)Average age at diagnosisReceived surgery (%)Received chemotherapy (%)Received radiation therapy (%)HRb (95% CI)
All patients with cancer1632931 (57.0%)6,9714.35.468.873.945.718.0
 Lifetime never nonsmokers340170 (50.0%)1,6965.07.568.676.543.217.11.00 (reference)
 Former smokers at cancer diagnosis545270 (49.5%)1,9443.65.971.476.944.214.30.97 (0.79–1.19)
 Current smokers at cancer diagnosis747491 (65.7%)3,3314. (0.91–1.41)
Patients with cancer who were current smokers at cancer diagnosis and survived until the next annual follow-up interview
 Quitters after cancer diagnosis (r = 0)214120 (56.1%)6963.34.468.974.351.912.61.00 (reference)
 Intermittent smokers after cancer diagnosis (r >0 and r <1)336223 (66.4%)2,1526.47.165.874.748.525.90.89 (0.70–1.12)
 Continued smokers after cancer diagnosis (r = 1)197148 (75.1%)4822. (1.37–2.27)
  • aPerson-years at risk began at one year after cancer diagnosis (see details in the Materials and Methods).

  • bAll Cox models were adjusted for age at diagnosis (continuous), level of education (primary school, middle school, or college or above), cumulative number of pack-year of smoking before diagnosis (continuous), treatment modalities: surgery (yes/no), chemotherapy (yes/no), and radiation therapy (yes/no), and cancer site.