Chronic obstructive pulmonary disease (COPD) is a common chronic respiratory disease with increased prevalence in the elderly. Telomeres are repetitive DNA sequences found at the end of the chromosome, which progressively shorten as cells divide. Telomere length is known to be a molecular marker of aging. This study aimed to assess the relationship between telomere length and the risk of COPD, lung function, respiratory symptoms, and emphysema index in Chronic Obstructive Pulmonary Disease in Dusty Areas (CODA) cohort.
We extracted DNA from the peripheral blood samples of 446 participants, including 285 COPD patients and 161 control participants. We measured absolute telomere length using quantitative real-time polymerase chain reaction. All participants underwent spirometry and quantitative computed tomography scan. Questionnaires assessing respiratory symptoms and the COPD Assessment Test was filled by all the participants.
The mean age of participants at the baseline visit was 72.5±7.1 years. Males accounted for 72% (321 participants) of the all participants. The mean telomere length was lower in the COPD group compared to the non-COPD group (COPD, 16.81±13.90 kb; non-COPD, 21.97±14.43 kb). In COPD patients, 112 (75.7%) were distributed as tertile 1 (shortest), 91 (61.1%) as tertile 2 and 82 (55%) as tertile 3 (longest). We did not find significant associations between telomere length and lung function, exacerbation, airway wall thickness, and emphysema index after adjusting for sex, age, and smoking status.
In this study, the relationship between various COPD phenotypes and telomere length was analyzed, but no significant statistical associations were shown.
Chronic obstructive pulmonary disease (COPD) is a major and increasing global health problem with large healthcare costs
Telomeres are repetitive DNA sequences, with high G-C content, at the end of chromosome protection. They protect chromosomal ends from being recognized as double-strand breaks and therefore protecting them from end-to-end fusion and degradation
Several studies have shown a significant relationship between reduced telomere length in peripheral blood leukocytes and increased risk of malignancy, cardiovascular disease, and diabetes mellitus
Since COPD is a heterogeneous disease with variable phenotypes
The Participants of the Chronic Obstructive Pulmonary Disease in Dusty Areas (CODA) cohort were analyzed
At baseline examinations, a medical interview and survey questionnaire were administered, and spirometry, physical examination, blood/urine sampling, and CT were performed for all participants. The questionnaire evaluated demographic factors, lifestyle factors, medical history, exacerbation history, and respiratory symptoms during the past year. We defined moderate exacerbation as a history of antibiotics or steroid use for more than two times, and severe exacerbation as more than one hospitalization due to respiratory symptoms within a year.
A written informed consent was given by each participant. This study also received ethical approval from the Institutional Review Board of Kangwon National University Hospital (KNUH 2020-06-007).
Dyspnea was evaluated using the modified Medical Research Council (mMRC) scoring system
Spirometry was measured yearly using the Easy One Kit (NDD Medizintechnik AG, Zurich, Switzerland), before and after inhalation of 400-μg salbutamol. All pulmonary function tests were performed according to the guidelines of the American Thoracic Society/European Respiratory Society
All participants underwent volumetric, thin-section, chest CT at full inspiration and expiration in the supine position. CT images were acquired using a first-generation, dual-source scanner (Somatom Definition, Siemens Healthcare, Forchheim, Germany) in the caudocranial direction using the following parameters: 140 kVp, 100 mA, 0.9–1 beam pitch, and slice thickness of 0.6 mm and 3 mm. The CT data were reconstructed using a soft convolution kernel (B30f)
Venous blood samples were obtained at baseline and DNA was extracted from the buffy coat. Telomere length was measured in DNA isolated from leukocytes. We modified the Cawthon method for relative measurement of telomere length by introducing an oligomer standard to measure absolute telomere length (aTL). In this approach, aTL was calculated by quantitative polymerase chain reaction according to by O’Callaghan and Fenech method
The telomere lengths of all samples were normalized to a reference cell line control sample, which was evaluated on each plate. Telomere length measurements (kb/genome) were normalized by natural log-transformation. For analysis, we divided the participants into three tertiles according to their telomere lengths.
Four hundred and forty-six participants were divided into were divided into two groups; COPD and non-COPD groups. COPD was defined according to GOLD (Global Initiative for Chronic Obstructive Lung Disease) with post-bronchodilator FEV1/forced vital capacity (FVC) <0.70. For analysis, the telomere length for each group (all participants, COPD group and non-COPD group) were divided into tertile groups. Comparison of baseline characteristics between COPD group and non-COPD group were performed using a Student t test and chi-square test. Categorical variable were described as number (%). Continuous variables were reported as the mean±standard deviation. The lung function, mMRC, and CAT score were evaluated using a general linear model adjusting for age, sex, smoking status, and height. To compare the trend of lung function decline according to the tertile groups, we used a mixed model adjusting for age, sex, and smoking status. Logistic regression was used to find the association between telomere length and COPD exacerbation. Odds ratios (ORs) and 95% confidence intervals (CI) were calculated using logistic regression model after adjusting for sex, age, and smoking status. For trend tests, individuals were categorized according to telomere length tertile (coded 1–3) with the first tertile consisting of individuals with the shortest telomere lengths. Those with p-values less than 0.05 were considered statistically significant. All analyses were performed using SAS version 9.4 (SAS Institute Inc., Cary, NC, USA).
The clinical characteristics, respiratory symptoms, and lung functions of the 446 participants at baseline are summarized in
We divided the participants into three groups depending on the telomere length (tertile 1, <8.54; tertile 2, 8.54–23.54; tertile 3, >23.54). A total of 285 participants (63.9%) had a FEV1/FVC <0.70. In COPD patients, 112 (75.7%) were distributed as tertile 1, 91 (61.1%) as tertile 2, and 82 (55%) as tertile 3 (
In all participants and COPD patients, shorter telomere length in tertile was associated with decreased FVC L at pre-bronchodilator (p trend, <0.001 and <0.001, respectively) (
Of the 446 participants, 25 were excluded from the visual assessment of the CT scans due to severe lung distortion and other lung morbidity. Finally, we analyzed 421 participants. Among the 285 patients with COPD, 13 were excluded from the visual assessment of CT scans; only 272 patients were included in the analysis. There were no statistically significant associations between telomere length and emphysema index, mean wall area, and CT subtypes in all participants and COPD patients (
We did not establish a significant association between telomere length and COPD exacerbation in COPD patients. In multivariable analyses, OR for the shortest versus the longest telomere tertile was 0.707 (95% CI, 0.153–3.274) for moderate exacerbation and 0.788 (0.203–3.057) for severe exacerbation (
We investigated the relationship between telomere length and the lung function, respiratory symptoms, emphysema extent, and airway wall thickness in a Korean COPD cohort living near cement plants. Disappointingly, we did not observe significant associations between telomere length and lung function, exacerbation, airway wall thickness, and emphysema index after adjusting for sex, age, and smoking status. However, although no statistical significances have been shown, some tendencies were shown along the telomere length tertile. It was shown that FEV1/FVC (pre-, post-bronchodilator) decreased with shorter telomere length in all participants and in the non-COPD group. The shorter telomere length was shown to decrease FVC (pre-, post-bronchodilator) in COPD group. In all participants and COPD patients, the shorter the telomere length, the lower the FVC (pre-bronchodilator), indicating a decline in the lung function change. On the other hand, in the non-COPD group, the shorter the telomere length, the lower the FVC (post-bronchodilator), indicating an increase in the lung function change. In addition, the shorter the telomere length, the wider the mean wall area in non-COPD group.
COPD is an age-related disease. An accelerated rate of lung function decline with age is one of the central pathophysiological characteristics of COPD. Previous studies have shown that leukocyte telomeres can be like biomarkers in cellular aging
Rode et al. reported that FEV1, FVC and FEV1/FVC decreased with decreasing telomere length quartile (p trend, 5×10−51, 5×10−35, and 6×10−137, respectively) but the associations attenuated after age and multivariable adjustments. In addition, participants with shorter telomeres were 2.06-fold more likely to develop COPD. The results showed that short telomere length is associated with reduced lung function and an increased prevalence of COPD
One study reported that shorter leukocyte telomere length may be a biomarker associated with a poor clinical prognosis in COPD, where short telomere length was associated with reduced quality of life and increased risk of exacerbation and mortality in patients with moderate-to-severe COPD
No significant associations were found between the emphysema index, mean wall area and telomere length in the all participants and COPD patients (p trend, 0.486, 0.669, 0.553, and 0.328, respectively). In the sub-analysis, the correlation of the average telomere length and emphysema CT subtype did not show a statistically significant trend in all participants and COPD group (p trend, 0.179 and 0.390, respectively). In addition, we did not observe any association between telomere length and airway wall thickness, emphysema index and visual CT image features in non-COPD group. However, we established that the shorter the telomere length, the wider the mean wall area in non-COPD group.
The MESA (Multi-Ethnic Study of Atherosclerosis) study found that the presence of centrilobular and panlobular emphysema correlated with increased dyspnea and reduced exercise capacity
Smoking is a well-known environmental factor that promotes aging and cellular senescence
It is worth noting that this is the first study to examine the relationship between telomere length and the phenotypes of COPD in Koreans. Our study investigated the relationship between telomere length and the extent of emphysema, airway wall thickness, and visual assessment on CT scans. Some studies have demonstrated that emphysema as assessed by CT imaging is a good predictor of mortality in COPD patients at various stages of the disease. Although it is still unclear whether emphysema predisposes COPD patients to such systemic manifestations and whether these systemic manifestations contribute to the development of emphysema, it is apparent that recognizing the extent of emphysema is important in evaluating COPD. Taken together, the evaluation of emphysema seems to be beneficial in the management of COPD
Nevertheless, this study has several limitations. First, the small sample size resulted in limited power to detect differences between telomere length and COPD-related phenotypes. Further large-scale studies with longer follow-up periods involving several serial assessments are needed to validate our findings.
Second, telomere length is a complex characteristic that is shaped by several factors, including genetic, epigenetic, lifestyle and environmental determinants. The complex interactions of these factors remain unclear
Third, we measured the leukocyte telomere length. Regarding this point, it is important to note that a correlation between lung and blood telomere length has not been unequivocally demonstrated. This suggests that the associations between telomere length and various diseases cannot easily be interpreted as causative relationship.
In conclusion, the correlation between lung function, respiratory symptoms, or extent and visual assessment and telomere length were analyzed, we did not find statistically significant results. Further studies are needed on the role of telomere length in COPD pathogenesis, as well as the relationship between telomere length and environmental factors including air pollution.
Conceptualization: Kim WJ, Moon DH. Methodology: Kim WJ, Moon DH, Kim J. Formal analysis: Lim MN. Data Curation: Lim MN. Software: Lim MN. Validation: Lim MN, Kim WJ, Moon DH. Investigation: Kim WJ, Moon DH, Kim J. Writing – original draft preparation: Moon DH, Kim WJ. Writing – review and editing: Moon DH, Kim J, Lim MN, Bak SH, Kim WJ. Approval of the final manuscript: all authors.
No potential conflict of interest relevant to this article was reported.
No funding to declare.
Supplementary material can be found in the journal homepage (
Clinical demographic characteristics, respiratory symptom and pulmonary function of non-COPD patients (n=161).
Change in FVC and FEV1 according to telomere length (non-COPD patients, n=161).
The association between telomere length and visual and quantitative CT imaging features in COPD patients (n=272).
The association between telomere length and visual and quantitative CT imaging features in non-COPD participants (n=149).
Flowchart of the study population. CT: computed tomography; COPD: chronic obstructive pulmonary disease; FEV1: forced expiratory volume in 1 second; FVC: forced vital capacity.
Baseline characteristics of the study participants
Characteristic | Total | COPD | Non-COPD | p-value |
---|---|---|---|---|
Participants | 446 | 285 (63.9) | 161 (36.1) | |
Telomere length, kb | 18.68±14.29 | 16.81±13.90 | 21.97±14.43 | <0.001 |
Sex | <0.001 | |||
Male | 321 (72.0) | 227 (79.7) | 94 (58.4) | |
Female | 125 (28.0) | 58 (20.3) | 67 (41.6) | |
Age, yr | 72.54±7.09 | 72.86±7.01 | 71.96±7.22 | 0.199 |
Smoking | <0.001 | |||
Current | 95 (21.3) | 74 (26.0) | 21 (13.0) | |
Former | 185 (41.5) | 134 (47.0) | 51 (31.7) | |
None | 166 (37.2) | 77 (27.0) | 89 (55.3) | |
Pack-year | 17.40±23.36 | 20.22±25.08 | 12.26±18.98 | 0.001 |
CAT | 16.20±9.63 | 17.11±9.60 | 14.60±9.50 | 0.008 |
mMRC | 1.37±1.14 | 1.47±1.14 | 1.18±1.10 | 0.009 |
Pre-bronchodilator | ||||
FVC, L | 2.86±0.80 | 2.89±0.82 | 2.79±0.75 | 0.195 |
FVC, % predicted | 93.46±19.99 | 92.28±20.86 | 95.57±18.21 | 0.095 |
FEV1, L | 1.86±0.59 | 1.74±0.58 | 2.08±0.54 | <0.001 |
FEV1, % predicted | 83.88±23.29 | 76.19±21.07 | 97.48±20.73 | <0.001 |
FEV1/FVC | 65.13±11.49 | 59.78±9.22 | 74.58±8.68 | <0.001 |
Post-bronchodilator | ||||
FVC, L | 2.99±0.80 | 3.10±0.81 | 2.81±0.75 | 0.001 |
FVC, % predicted | 97.74±19.21 | 98.55±19.36 | 96.32±18.92 | 0.239 |
FEV1, L | 1.94±0.59 | 1.83±0.57 | 2.14±0.56 | <0.001 |
FEV1, % predicted | 87.47±22.63 | 80.10±19.99 | 100.50±21.15 | <0.001 |
FEV1/FVC | 65.25±11.44 | 58.84±8.61 | 76.58±5.45 | <0.001 |
IL-8 (n=359) | 18.06±22.31 | 16.89±18.10 | 21.27±30.96 | 0.194 |
IL-6 (n=359) | 2.52±3.48 | 2.51±3.66 | 2.57±2.94 | 0.867 |
CRP (n=359) | 0.28±0.62 | 0.26±0.59 | 0.31±0.70 | 0.475 |
Values are presented as number (%) or mean±SD and analyzed with the t test or chi-square test.
COPD: chronic obstructive pulmonary disease; CAT: COPD Assessment Test; mMRC: modified Medical Research Council; FVC: forced vital capacity; FEV1: forced expiratory volume in 1 second; IL-8: interleukin-8; IL-6: interleukin-6; CRP: C-reactive protein.
Clinical demographic characteristics, respiratory symptom and lung function of all participants (n=446)
Total | Tertile 1 (<8.54) | Tertile 2 (8.54–23.54) | Tertile 3 (>23.54) | Unadjusted p trend | Adjusted p trend | |
---|---|---|---|---|---|---|
Participants | 446 | 148 (33.2) | 149 (33.4) | 149 (33.4) | ||
Telomere length, kb | 18.68±14.29 | 4.73±2.52 | 15.46±4.53 | 35.75±9.43 | <0.001 | |
COPD | <0.001 | |||||
Yes | 285 (63.9) | 112 (75.7) | 91 (61.1) | 82 (55.0) | ||
No | 161 (36.1) | 36 (24.3) | 58 (38.9) | 67 (45.0) | ||
Sex | 0.437 | |||||
Male | 321 (72.0) | 112 (75.7) | 106 (71.1) | 103 (69.1) | ||
Female | 125 (28.0) | 36 (24.3) | 43 (28.9) | 46 (30.9) | ||
Age, yr | 72.54±7.09 | 72.96±6.86 | 71.85±7.39 | 72.80±7.02 | 0.346 | |
Smoking | 0.150 | |||||
Current | 95 (21.3) | 41 (27.7) | 26 (17.5) | 28 (18.8) | ||
Former | 185 (41.5) | 61 (41.2) | 64 (42.9) | 60 (40.3) | ||
None | 166 (37.2) | 46 (31.1) | 59 (39.6) | 61 (40.9) | ||
Pack-year | 17.40±23.36 | 21.28±25.45 | 14.05±18.87 | 16.97±24.82 | 0.029 | |
CAT | 16.20±9.63 | 16.74±0.91 | 16.17±0.93 | 15.79±0.93 | 0.772 | 0.697 |
mMRC | 1.37±1.14 | 1.31±0.11 | 1.38±0.11 | 1.33±0.11 | 0.863 | 0.855 |
Pre-bronchodilator | ||||||
FVC, L | 2.86±0.80 | 2.73±0.06 | 2.77±0.07 | 2.83±0.06 | 0.943 | 0.369 |
FVC, % predicted |
93.46±19.99 | 94.16±1.79 | 93.53±1.84 | 97.07±1.82 | 0.176 | 0.249 |
FEV1, L | 1.86±0.59 | 1.76±0.05 | 1.82±0.05 | 1.88±0.05 | 0.410 | 0.143 |
FEV1, % predicted |
83.88±23.29 | 83.50±2.02 | 83.78±2.08 | 88.66±2.05 | 0.034 | 0.077 |
FEV1/FVC | 65.13±11.49 | 64.19±1.00 | 66.03±1.03 | 66.90±1.02 | 0.031 | 0.096 |
Post-bronchodilator | ||||||
FVC, L | 2.99±0.80 | 2.89±0.06 | 2.87±0.06 | 2.97±0.06 | 0.793 | 0.284 |
FVC, % predicted |
97.74±19.21 | 99.38±1.73 | 96.80±1.78 | 101.64±1.76 | 0.081 | 0.086 |
FEV1, L | 1.94±0.59 | 1.84±0.05 | 1.89±0.05 | 1.96±0.05 | 0.492 | 0.135 |
FEV1, % predicted |
87.47±22.63 | 87.23±1.98 | 86.68±2.03 | 92.20±2.01 | 0.027 | 0.052 |
FEV1/FVC | 65.25±11.44 | 63.84±1.01 | 65.94±1.03 | 66.66±1.02 | 0.213 | 0.072 |
IL-8 (n=263) | 16.89±18.10 | 16.82±17.86 | 15.73±13.28 | 18.37±22.92 | 0.664 | |
IL-6 (n=263) | 2.51±3.66 | 2.56±4.18 | 2.71±3.49 | 2.19±2.95 | 0.668 | |
CRP (n=263) | 0.26±0.59 | 0.27±0.58 | 0.29±0.73 | 0.22±0.41 | 0.740 | |
Exacerbation | ||||||
Moderate | 10 (3.5) | 3 (2.7) | 3 (3.3) | 4 (4.9) | 0.707 | |
Severe | 13 (4.6) | 4 (3.6) | 4 (4.4) | 5 (6.1) | 0.704 | |
Moderate or severe | 18 (6.3) | 6 (5.4) | 6 (6.6) | 6 (7.3) | 0.850 |
Values are presented as number (%) or mean±SD and analyzed with the t test or chi-square test.
Study participants were divided into three groups based on telomere length, with the first tertile being the shortest and the third tertile being the longest.
Adjusted variables: sex, age, smoking status, height.
Adjusted variables: sex, age, smoking status.
COPD: chronic obstructive pulmonary disease; CAT: COPD Assessment Test; mMRC: modified Medical Research Council; FVC: forced vital capacity; FEV1: forced expiratory volume in 1 second; IL-8: interleukin-8; IL-6: interleukin-6; CRP: C-reactive protein.
Clinical demographic characteristics, respiratory symptom and pulmonary function of COPD patients (n=285)
Tertile 1 |
Tertile 2 |
Tertile 3 |
Unadjusted p trend | Adjusted p trend | ||
---|---|---|---|---|---|---|
Participants | 285 | 95 (33.3) | 95 (33.3) | 95 (33.3) | ||
Telomere length | 18.68±14.29 | 4.11±2.30 | 12.89±4.13 | 33.44±10.17 | <0.001 | |
Sex | 0.206 | |||||
Male | 227 (79.6) | 79 (83.2) | 70 (73.7) | 78 (82.1) | ||
Female | 58 (20.4) | 16 (16.8) | 25 (26.3) | 17 (17.9) | ||
Age | 72.86±7.01 | 73.29±7.04 | 72.69±7.32 | 72.61±6.73 | 0.768 | |
Smoking | 0.215 | |||||
Current | 74 (26.0) | 28 (29.5) | 25 (26.3) | 21 (22.1) | ||
Former | 134 (47.0) | 48 (50.5) | 38 (40.0) | 48 (50.5) | ||
None | 77 (27.0) | 19 (20.0) | 32 (33.7) | 26 (27.4) | ||
Pack-year | 20.30±25.08 | 25.31±27.03 | 15.05±19.10 | 20.71±27.44 | 0.020 | |
CAT | 17.11±9.60 | 16.87±1.18 | 17.57±1.21 | 16.67±1.27 | 0.680 | 0.886 |
mMRC | 1.47±1.14 | 1.36±0.14 | 1.56±0.14 | 1.43±0.15 | 0.283 | 0.697 |
Pre-bronchodilator | ||||||
FVC, L | 2.89±0.82 | 2.77±0.08 | 2.88±0.09 | 2.89±0.09 | 0.823 | 0.217 |
FVC, % predicted |
92.28±20.86 | 93.86±2.44 | 96.56±2.41 | 96.37±2.53 | 0.525 | 0.403 |
FEV1, L | 1.74±0.58 | 1.68±0.06 | 1.74±0.06 | 1.72±0.07 | 0.962 | 0.593 |
FEV1, % predicted |
76.19±21.07 | 77.55±2.47 | 79.66±2.44 | 77.90±2.56 | 0.637 | 0.908 |
FEV1/FVC | 59.79±9.22 | 60.31±1.09 | 60.10±1.08 | 59.51±1.13 | 0.853 | 0.552 |
Post-bronchodilator | ||||||
FVC, L | 3.10±0.81 | 2.93±0.08 | 3.00±0.08 | 3.06±0.08 | 0.517 | 0.157 |
FVC, % predicted |
98.55±19.36 | 99.22±2.28 | 100.67±2.25 | 102.23±2.37 | 0.562 | 0.319 |
FEV1, L | 1.83±0.57 | 1.76±0.06 | 1.79±0.06 | 1.81±0.06 | 0.734 | 0.512 |
FEV1, % predicted |
80.10±19.99 | 81.25±2.35 | 82.12±2.32 | 81.66±2.45 | 0.881 | 0.889 |
FEV1/FVC | 58.84±8.61 | 59.46±1.02 | 59.33±1.01 | 58.97±1.06 | 0.931 | 0.695 |
IL-8 (n=263) | 16.89±18.10 | 17.10±19.12 | 16.35±12.85 | 17.24±21.65 | 0.941 | |
IL-6 (n=263) | 2.51±3.66 | 2.51±4.27 | 2.91±3.67 | 2.06±2.78 | 0.311 | |
CRP (n=263) | 0.26±0.59 | 0.25±0.54 | 0.33±0.77 | 0.20±0.38 | 0.378 | |
Exacerbation | ||||||
Moderate | 10 (3.5) | 3 (3.2) | 3 (3.2) | 4 (4.2) | 0.902 | |
Severe | 13 (4.6) | 4 (4.2) | 4 (4.2) | 5 (5.3) | 0.923 | |
Moderate or severe | 18 (6.3) | 6 (6.3) | 6 (6.3) | 6 (6.3) | - |
Values are presented as number (%) or mean±SD and analyzed with the t test or chi-square test.
Adjusted variables: sex, age, smoking status, height.
COPD patients were divided into three groups based on telomere length, with the first tertile being the shortest and the third tertile being the longest.
Adjusted variables: sex, age, smoking status.
COPD: chronic obstructive pulmonary disease; CAT: COPD Assessment Test; mMRC: modified Medical Research Council; FVC: forced vital capacity; FEV1: forced expiratory volume in 1 second; IL-8: interleukin-8; IL-6: interleukin-6; CRP: C-reactive protein.
Change in FVC and FEV1 according to telomere length (all participants, n=446)
Tertile 1 (<8.54) | Tertile 2 (8.54–23.54) | Tertile 3 (>23.54) | p trend | |
---|---|---|---|---|
Pre-bronchodilator | ||||
FVC, mL/yr | −4.294±1.707 | −5.086±1.898 | −6.044±2.187 | <0.001 |
FEV1, mL/yr | −2.675±1.692 | −3.796±1.820 | −3.304±2.000 | 0.736 |
Post-bronchodilator | ||||
FVC, mL/yr | −2.467±1.577 | −3.480±1.737 | −2.578±1.990 | 0.952 |
FEV1, mL/yr | −2.199±0.903 | −2.709±0.975 | −1.364±1.094 | 0.409 |
Study participants were divided into three groups based on telomere length, with the first tertile being the shortest and the third tertile being the longest.
Adjusted variables: sex, age, smoking status, height.
FVC: forced vital capacity; FEV1: forced expiratory volume in 1 second.
Change in FVC and FEV1 according to telomere length (COPD patients, n=285)
Tertile 1 |
Tertile 2 |
Tertile 3 |
p trend | |
---|---|---|---|---|
Pre-bronchodilator | ||||
FVC, mL/yr | −5.652±2.004 | −6.358±2.248 | −7.346±2.706 | <0.001 |
FEV1, mL/yr | −3.297±2.005 | −5.225±2.197 | −4.206±2.477 | 0.679 |
Post-bronchodilator | ||||
FVC, mL/yr | −5.003±1.900 | −5.368±2.114 | −4.606±2.518 | 0.856 |
FEV1, mL/yr | −2.463±0.975 | −2.958±1.078 | −1.998±1.269 | 0.674 |
Adjusted variables: sex, age, smoking status, height.
COPD patients were divided into three groups based on telomere length, with the first tertile being the shortest and the third tertile being the longest.
FVC: forced vital capacity; FEV1: forced expiratory volume in 1 second; COPD: chronic obstructive pulmonary disease.
The association between telomere length and visual and quantitative CT imaging features in all participants (n=421)
Variable | Total | Tertile 1 (<8.54) | Tertile 2 (8.54–23.54) | Tertile 3 (>23.54) | p trend | ||||
---|---|---|---|---|---|---|---|---|---|
|
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No. (%) | Mean±SD | No. (%) | Mean±SD | No. (%) | Mean±SD | No. (%) | Mean±SD | ||
Participants | 421 | 142 (33.7) | 139 (33.0) | 140 (33.3) | |||||
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Emphysema index | 5.69±6.55 | 6.22±6.35 | 5.33±5.84 | 5.51±7.38 | 0.486 | ||||
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Mean wall area, % | 68.85±5.19 | 69.85±0.56 | 68.95±0.63 | 70.79±0.68 | 0.669 | ||||
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CT subtype | |||||||||
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Normal | 199 (47.3) | 19.02±1.27 | 55 (38.7) | 4.31±0.96 | 67 (48.2) | 15.20±0.92 | 77 (55.0) | 34.67±0.87 | |
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PSE | 30 (7.1) | 15.18±2.75 | 14 (9.9) | 5.19±2.51 | 10 (7.2) | 16.64±2.22 | 6 (4.3) | 34.09±3.09 | |
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Bronchial | 10 (2.4) | 24.11±4.47 | 0 (0) | 5 (3.6) | 15.90±5.21 | 5 (3.6) | 33.78±5.93 | ||
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Trace | 48 (11.4) | 14.94±2.17 | 23 (16.2) | 2.10±1.58 | 12 (8.6) | 15.22±1.86 | 13 (9.3) | 34.43±1.93 | |
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Mild | 82 (19.5) | 16.90±1.75 | 29 (20.4) | 4.63±1.48 | 32 (23.0) | 12.81±1.62 | 21 (15.0) | 35.33±1.74 | |
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Moderate | 38 (9.0) | 18.01±2.44 | 17 (12.0) | 4.61±2.95 | 11 (7.9) | 16.42±3.77 | 10 (7.1) | 38.50±3.75 | |
| |||||||||
Confluent and advanced | 14 (3.3) | 23.90±3.94 | 4 (2.8) | 0.64±5.32 | 2 (1.4) | 11.38±5.78 | 8 (5.7) | 35.47±3.14 | |
| |||||||||
p trend | 0.179 | 0.537 | 0.518 | 0.830 |
Study participants were divided into three groups based on telomere length, with the first tertile being the shortest and the third tertile being the longest.
Adjusted variables: sex, age, smoking status.
CT: computed tomography; SD: standard deviation; PSE: paraseptal emphysema.
The OR of exacerbation according to telomere length (COPD patients, n=285)
Moderate | Severe | Moderate or severe | |
---|---|---|---|
Telomere length | |||
Tertile 1 |
0.707 (0.153–3.274) | 0.788 (0.203–3.057) | 0.997 (0.307–3.241) |
Tertile 2 |
0.681 (0.146–3.184) | 0.781 (0.200–3.050) | 0.966 (0.295–3.157) |
p-value | 0.859 | 0.919 | 0.998 |
Adjusted variables: sex, age, smoking status, height.
COPD patients were divided into three groups based on telomere length, with the first tertile being the shortest and the third tertile being the longest.
OR: odds ratio; COPD: chronic obstructive pulmonary disease.