title: Can Angiotensin-Converting Enzyme Inhibitors Reduce the Incidence, Severity, and Duration of Radiation Proctitis?
abstract: OBJECTIVE
  To determine whether participants taking angiotensin-converting enzyme inhibitors (ACEIs) and treated with radical radiation therapy with neoadjuvant/adjuvant hormone therapy have less incidence, severity, and duration of radiation proctitis.
  
  
  METHODS
  A propensity score analysis of 817 patients who underwent radical radiation therapy with neoadjuvant or adjuvant hormone therapy as primary line management in a cohort study during 2009 to 2013 was conducted. Patients were stratified as follows: group 1, hypertensive patients taking ACEIs (as a study group); group 2, nonhypertensive patients not taking ACEIs; and group 3, hypertensive patients not taking ACEIs (both as control groups). The incidence, severity, and duration of proctitis were the main outcome. χ(2) tests, Mann-Whitney U tests, analysis of variance, risk ratio (RR), confidence interval (CI), Kaplan-Meier plots, and log-rank tests were used.
  
  
  RESULTS
  The mean age of the participants was 68.91 years, with a follow-up time of 3.38 years. Based on disease and age-matched comparison, there was a statistically significant difference of proctitis grading between the 3 groups: χ(2) (8, n=308) = 72.52, P<.001. The Mann-Whitney U test indicated that grades of proctitis were significantly lower in hypertensive patients taking ACEIs than in nonhypertensive patients not taking ACEIs and hypertensive patients not taking ACEIs (P<.001). The risk ratio (RR) of proctitis in hypertensive patients taking ACEIs was significantly lower than in hypertensive patients not taking ACEIs (RR 0.40, 95% CI 0.30-0.53, P<.001) and in nonhypertensive patients not taking ACEIs (RR 0.58, 95% CI 0.44-0.77, P<.001). Time to event analysis revealed that hypertensive patients taking ACEIs were significantly different from the control groups (P<.0001). Furthermore, hypertensive patients taking ACEIs had significantly faster resolution of proctitis (P<.0001).
  
  
  CONCLUSIONS
  Patients who were taking ACEIs were significantly less likely to have high-grade proctitis after radical radiation therapy with neoadjuvant or adjuvant hormone therapy (P<.001). The intake of ACEIs was significantly associated with a reduced risk of radiation-induced proctitis and also with acceleration of its resolution.
authors.affiliation: Academic Section of Urology, Division of Cancer Research, School of Medicine, University of Dundee, Scotland, UK. Electronic address: alashkham@yahoo.com.
authors.forename: Abduelmenem
authors.initials: A
authors.lastname: Alashkham
authors.affiliation: Academic Section of Urology, Division of Cancer Research, School of Medicine, University of Dundee, Scotland, UK.
authors.forename: Catherine
authors.initials: C
authors.lastname: Paterson
authors.affiliation: Tayside Clinical Trials Unit, School of Medicine, University of Dundee, Scotland, UK.
authors.forename: Petra
authors.initials: P
authors.lastname: Rauchhaus
authors.affiliation: Academic Section of Urology, Division of Cancer Research, School of Medicine, University of Dundee, Scotland, UK.
authors.forename: Ghulam
authors.initials: G
authors.lastname: Nabi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D016009:Chi-Square Distribution; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy / Q000379:methods; D060787:Neoplasm Grading; D011349:Proctitis / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D057216:Propensity Score; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D018709:Statistics, Nonparametric; D013997:Time Factors
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors