title: Telomere Shortening in Blood Leukocytes of Patients with Chronic Obstructive Pulmonary Disease.
abstract: BACKGROUND
  Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation that is not completely reversible by administration of inhaled bronchodilators. Many studies propose that telomere length shortening might have occurred in COPD patients. We aimed to determine the telomere length in COPD patients and compare the results of non-smoking and smoking control subjects.
  
  
  METHODS
  In our case-control study, 84 clinically stable COPD patients were recruited on admission to Masih Daneshvari Hospital. Eighty-five healthy controls were also selected including 45 non-smokers and 40 smokers admitted for diseases other than COPD. Spirometry was done for all subjects. Telomere length was measured by quantitative real time PCR as described by Cawthon. The telomere repeat copy number (T) to single-gene copy number (S) ratio was calculated using the comparative Ct method.
  
  
  RESULTS
  The mean ±SD of age was 64.33±10.04 years in patients and 65.06 ±10.02 years in controls (P=0.693). The mean ±SD of FEV1 was 1.62±0.75 L in patients, 2.84±0.54 L in smoker controls and 2.83±0.56 L in non-smoker controls; significant differences were detected in this regard between cases and controls (P<0.001). T/S ratio was significantly lower in COPD patients (0.61±0.08) than in the control subjects (0.69±0.09) (P<0.001). However, telomere length was shorter in the patients than in controls in each age group (P<0.001). Additionally, there were no statistically significant differences in telomere length between the smoker and non-smoker control subjects. Regarding the correlation between BMI and telomere length, there were no significant differences among the patients and control groups.
  
  
  CONCLUSIONS
  In conclusion, we found that telomere length in COPD patients was shorter than that in smoker and non-smoker controls, irrespective of age, sex, spirometric variables, BMI and history of cigarette smoking.
authors.affiliation: Department of Anatomy, Faculty of Medicine Tehran University of Medical Sciences (TUMS), Tehran, Iran ; Virology Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Makan
authors.initials: M
authors.lastname: Sadr
authors.affiliation: Department of Anatomy, Faculty of Medicine Tehran University of Medical Sciences (TUMS), Tehran, Iran.
authors.forename: Seyed Mohammad Hossein
authors.initials: SM
authors.lastname: Noori Mugahi
authors.affiliation: Department of Anatomy, Faculty of Medicine Tehran University of Medical Sciences (TUMS), Tehran, Iran.
authors.forename: Gholamreza
authors.initials: G
authors.lastname: Hassanzadeh
authors.affiliation: Virology Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Seyed Alireza
authors.initials: SA
authors.lastname: Nadji
authors.affiliation: Tracheal Diseases Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Arda
authors.initials: A
authors.lastname: Kiani
authors.affiliation: Chronic Respiratory Diseases Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Atefeh
authors.initials: A
authors.lastname: Abedini
authors.affiliation: Virology Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Javadi
authors.affiliation: Virology Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Forozan
authors.initials: F
authors.lastname: Mohammadi
authors.affiliation: Chronic Respiratory Diseases Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Masjedi
authors.affiliation: Chronic Respiratory Diseases Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Moslem
authors.initials: M
authors.lastname: Bahadori
keywords: Aging; Chronic obstructive pulmonary disease; Telomere; Telomere length