title: Prevalence of hypertension and type 2 diabetes mellitus in patients with colorectal cancer and their median survival time: A cohort study.
abstract: BACKGROUND
  Type 2 diabetes mellitus (DM) and hypertension are worldwide epidemic. Association between DM and colon cancer was obtained in previous studies. Prevalence of DM and hypertension in the patients with colorectal cancer (CRC) has not been reported in Iran. The present study was aimed to investigate the prevalence of hypertension and type 2 DM and their effect on median survival time in patients with CRC.
  
  
  METHODS
  Overall, 2570 individual-year follow-ups were conducted for 1127 patients with CRC. For the diagnosis of type 2 DM, fasting blood sugar test and glycosylated hemoglobin test were used and for hypertension, blood pressure was measured in two turns. The descriptive indices were calculated, and the mean and median survival from CRC diagnosis time was calculated using survival analysis and a comparison among survival times was done through log-rank test. Stata software 12 (Stata Corp. 2011. Stata Statistical Software: Release 12. College Station, TX: Stata Corp LP) was used for data analysis.
  
  
  RESULTS
  The prevalence of hypertension and type 2 DM in the patients with CRC was respectively 13.38% (95% confidence interval [CI]: 11.1-15.8) and 8.69% (95% CI: 7-10.7). Median survival time in patients with hypertension and DM were 8.52 and 4.9 years. According to log-rank test, no significant difference was observed between the survival time of CRC patients suffering from hypertension and diabetes type 2.
  
  
  CONCLUSIONS
  The obtained findings in this study indicate that survival time in patients with type 2 DM less than hypertension but two metabolic diseases have the same effect on survival rate of the patients with CRC. Understanding the risk factors for CRC may guide the development of strategies targeted toward its prevention.
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Shahrekord University of Medical Sciences, Shahrekord, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Ahmadi
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Shahrekord University of Medical Sciences, Shahrekord, Iran.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Mobasheri
authors.affiliation: Department of Epidemiology, School of Public Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Seyed Saeed
authors.initials: SS
authors.lastname: Hashemi-Nazari
authors.affiliation: Department of Pathology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Azar
authors.initials: A
authors.lastname: Baradaran
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Shahrekord University of Medical Sciences, Shahrekord, Iran.
authors.forename: Zahra Molavi
authors.initials: ZM
authors.lastname: Choobini
keywords: Colorectal cancer; diabetes; hypertension; survival time