Background and Objectives Lung cancer is the most common cancer and cancer related cause of death worldwide. yr. During a mean follow up of 7.5 (��2.2) yr 150 cases of lung cancer occurred. Using 7 h of sleep as the reference group multivariable adjusted hazard ratios (95%CI) for lung cancer were 1.18 (0.77-1.82) 1 (ref) and 0.97 (0.67-1.41) from lowest to the highest category of sleep duration (for quadratic trend 0.697) respectively. In a secondary analysis smoking status did not change the sleep duration-lung cancer association (2002). If the data was not available at the baseline than the information from as close to sleep assessment as possible (usually from 12 mo prior questionnaire) was obtained. Age and body mass index (BMI) were used as continuous variables. Race was dichotomized as white non-white. Exercise was classified as rarely/never 1 1 and 5-7/wk. Smoking was classified as never past and current smokers. For alcohol consumption subjects were asked RAF265 (CHIR-265) the following question: ��How often do you usually consume alcoholic beverages?�� Possible responses were: rarely/never 1 times/mo 1 time/wk 2 times/wk 5 times/wk daily and ��2 times/d. These responses were interpreted as the number of alcoholic drinks consumed during the specified period. For current analyses alcohol consumption was classified as <1 1 5 and >7 drinks/wk. Diagnosis of T2D was self-reported and validated by detailed review of the medical records in a subsample[34]. Diagnosis of sleep apnea (Yes No) and snoring (rarely/never few/occasionally mostly/always and unknown/missing) parental history of cancer and caloric intake were based on self-reported information. For categorical variables indicator values were created for missing observations. We classified each subject into one of the following categories of average sleep duration: ��6 h 7 h and ��8 h. We computed person-time of follow up from the time when sleep duration was assessed until the first occurrence of a) confirmed lung cancer b) death or c) the date of last available follow up (August 1st 2011 Baseline demographic variables were recorded and compared across categories of sleep duration. We used proportional hazard models to compute multivariable adjusted hazard ratios (HR) with corresponding 95% confidence intervals (CI) using participants reporting 7 h of sleep duration as the reference group. Potential confounding was RAF265 (CHIR-265) assessed for established risk factors of lung cancer. First we adjusted for age and race in model 1. Second we also controlled for parental history of cancer exercise Rabbit Polyclonal to MARCH2. RAF265 (CHIR-265) frequency caloric intake BMI T2D alcohol consumption smoking status sleep apnea and snoring in model 2. To further RAF265 (CHIR-265) address confounding by age we calculated age-standardized incidence rate for lung cancer using year 2000 US Standard Population. In secondary analyses we evaluated whether there were statistically significant interactions between sleep duration and smoking status or sleep apnea by using a product term of both variables in a hierarchical model. Assumptions for proportional hazard models were tested (by including main effects and product terms of sleep duration and logarithmic-transformed time factor) and were met for all those variables except snoring (150 cases respectively). The participants with missing data on sleep duration were more likely to be older; current smokers heavy alcohol drinkers (>7/wk) had a higher prevalence of sleep apnea and sedentary lifestyle. They however were less likely to have parental history of cancer and had a lower caloric intake compared to people with complete data on sleep duration. Tab 2 Comparison of baseline characteristics between those with missing and people with complete data on sleep duration During a mean follow up of 7.5 (��2.2) yr 150 cases of lung cancer were diagnosed. Crude incidence rates of RAF265 (CHIR-265) lung cancer were 0.86 0.8 and 1.21 cases/1 0 person-years for people reporting an average sleep duration of ��6 h 7 h and ��8 h respectively (Table 3). Using 7 h of sleep as the reference group multivariable adjusted hazard ratios (95%CI) for lung cancer were 1.18 (0.77-1.82) 1 (ref) and 0.97 (0.67-1.41) from lowest to the highest category of sleep duration (for quadratic trend 0.697) respectively (Table 3). Tab 3 Hazard.