Television watching and colorectal cancer survival in men

Abstract

Purpose To assess the association between pre- and postdiagnostic time spent sitting watching TV as well as other sedentary behaviors (other sitting at home and at work/driving) and mortality from colorectal cancer or other causes, and overall mortality. Methods We followed stage I-III colorectal cancer patients from the Health Professionals Follow-up Study (1986–2010). Cox models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). Results 926 and 714 patients were included in the analysis of pre- and postdiagnostic TV watching respectively, and 471 and 325 died during follow-up. Prolonged prediagnostic TV viewing was associated with increased risk of colorectal cancer-specific mortality independent of leisure-time physical activity. The HRs (95% CIs) for 0–6, 7–13,14–20 and ≥21 h/wk were 1.00 (referent), 0.84 (0.56–1.25), 1.15 (0.75–1.78), 2.13 (1.31–3.45) (Ptrend=0.01). The association was observed primarily among overweight and obese individuals. Prediagnostic TV watching was also associated with overall mortality within 5 years of diagnosis, largely due to the association with colorectal cancer mortality. Other prediagnostic sitting at home or at work/driving was not associated with mortality. Postdiagnostic TV viewing was associated with non-significant increased risk of colorectal cancer-specific mortality (HR for ≥21 vs 0–6 h/wk=1.45; 95% CI 0.73–2.87) adjusting for TV viewing before diagnosis. Conclusion Prolonged prediagnostic TV watching is associated with higher colorectal cancer-specific mortality independent of leisure-time physical activity among colorectal cancer patients.

Postdiagnosis sedentary behavior and health outcomes in cancer survivors: A systematic review and meta‐analysis

“…[22][23][24][27][28][29] In addition, to rate the quality of evidence, this review used GRADE. First, although a meta-analysis examining the interaction between postdiagnosis sedentary behavior and both all-cause and CRC-specific mortality provides new information in this field, the likelihood of reverse causation in the primary studies must be acknowledged.…”

“…32,37,38,42 All 5 studies that examined anthropometric outcomes contained serious ROB. The sample size ranged from 580 to 2293 participants and included patients and survivors of colorectal, [22][23][24]27 breast, 26 endometrial, 21 hematologic, 28 prostate, 25 and renal cell 29 cancers. 49,53 Study Characteristics A summary of study characteristics is provided in Supporting Table 4.…”

“…This was because of cross-sectional design [49][50][51][52] and potential for systematic error in self-reported outcome assessment. All studies assessed sedentary behavior by self-report, with domains including television viewing time, 21,22,[26][27][28][29] total sitting time, 24 occupational sitting time, 25 and leisure time spent sitting. The 9 studies addressing mortality were prospective in design.…”

“…49,53 Study Characteristics A summary of study characteristics is provided in Supporting Table 4. 23 Every study reported all-cause mortality, 6 reported cancer-specific mortality, including CRC, [22][23][24] prostate cancer, 25 renal cancer, 29 and hematologic cancer. The sample size ranged from 580 to 2293 participants and included patients and survivors of colorectal, [22][23][24]27 breast, 26 endometrial, 21 hematologic, 28 prostate, 25 and renal cell 29 cancers.…”

“…The 9 studies addressing mortality were prospective in design. 28 Two studies reported mortality from CVD, 22,23 and 2 reported other mortality outcomes, 23,24 which included noncancer and non-CVD mortality as well as noncancer mortality. All studies assessed sedentary behavior by self-report, with domains including television viewing time, 21,22,[26][27][28][29] total sitting time, 24 occupational sitting time, 25 and leisure time spent sitting.…”