Gender Differences in Idiopathic Pulmonary Fibrosis: Are Men and Women Equal?

Background: Idiopathic pulmonary fibrosis (IPF) is characterized by a male predominance. The aim of the study was to explore gender differences in a well-designed French multicentre prospective IPF cohort (COhorte FIbrose, COFI) with a 5-year follow-up.

Methods: Between 2007 and 2010, 236 patients with incident IPF were included in COFI. Gender characteristics were compared using a t-test, Chi-squared test and ANOVA, as appropriate. Survival analyses were performed.

Results: Fifty-one (22%) females and 185 (78%) males with an average age at diagnosis of 70.1 ± 9.20 and 67.4 ± 10.9 years, respectively, were included in the cohort. Women were significantly less exposed to tobacco smoke [never n = 32 (62.7%) vs. n = 39 (21.1%), p < 0.001] and to occupational exposure [n = 7 (13.7%) vs. n = 63 (34.1%), p = 0.012]. Baseline forced vital capacity, % of predicted (FVC%) was significantly better in women compare to men (83.0% ± 25.0 v. 75.4% ± 18.7 p = 0.046). At presentation honeycombing and emphysema on CT scan were less common in women [n = 40 (78.4%) vs. n = 167 (90.3%) p = 0.041] and [n = 6 (11.8%) vs. n = 48 (25.9%) p = 0.029], respectively. During follow-up fewer women were transplanted compared to men [n = 1 (1.96%) vs. n = 20 (10.8%) p = 0.039]. Medians of survival were comparable by gender [31 months (CI 95%: 28–40) vs. 40 months (CI 95%: 33–72) p = 0.2]. After adjusting for age and FVC at inclusion, being a woman was not associated to a better survival.

Conclusions: Women appear to have less advanced disease at diagnosis, maybe due to less exposure history compare to men. Disease progression and overall survival remains comparable regardless gender, but women have less access to lung transplantation.

Low income and outcome in idiopathic pulmonary fibrosis: An association to uncover

BACKGROUND

Low income, a known prognostic indicator of various chronic respiratory diseases, has not been properly studied in idiopathic pulmonary fibrosis (IPF). We hypothesize that a low income has an adverse prognostic impact on IPF.

METHODS

Patients were selected from the French national prospective cohort COFI. Patients' income was assessed through the median city-level income provided by the French National Institute of Statistics and Economic Studies according to their residential address. Patients were classified in two groups as "low income" vs. "higher income" depending on whether their annual income was estimated to be < or ≥18 170 €/year (the first quartile of the income distribution in the study population). The survival and progression-free survival (PFS) of the groups were compared by a log-rank test and a Cox model in multivariate analysis.

RESULTS

200 patients were included. The average follow-up was 33.8 ± 22.7 months. Patients in the low income group were significantly more likely to be of non-European origin (p < 0.006), and to have at least one occupational exposure (p < 0.0001), and they tended to have a higher cumulative exposure to fine particles PM_2.5 (p = 0.057). After adjusting for age, gender, forced vital capacity at inclusion, geographical origin, and occupational exposure having a low-income level was a factor associated with a worse PFS (HR: 1.81; CI_95%: 1.24-2.62, p = 0.001) and overall survival (HR: 1.49; CI_95%: 1.0006-2.23, p = 0.049).

CONCLUSIONS

Low income appears to be a prognostic factor in IPF. IPF patients with low incomes may also be exposed more frequently to occupational exposures.

Role of atmospheric pollution on the natural history of idiopathic pulmonary fibrosis

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) has an unpredictable course corresponding to various profiles: stability, physiological disease progression and rapid decline. A minority of patients experience acute exacerbations (AEs). A recent study suggested that ozone and nitrogen dioxide might contribute to the occurrence of AE. We hypothesised that outdoor air pollution might influence the natural history of IPF.

METHODS

Patients were selected from the French cohort COhorte FIbrose (COFI), a national multicentre longitudinal prospective cohort of IPF (n=192). Air pollutant levels were assigned to each patient from the air quality monitoring station closest to the patient's geocoded residence. Cox proportional hazards model was used to evaluate the impact of air pollution on AE, disease progression and death.

RESULTS

Onset of AEs was significantly associated with an increased mean level of ozone in the six preceding weeks, with an HR of 1.47 (95% CI 1.13 to 1.92) per 10 µg/m³ (p=0.005). Cumulative levels of exposure to particulate matter PM₁₀ and PM_2.5 were above WHO recommendations in 34% and 100% of patients, respectively. Mortality was significantly associated with increased levels of exposure to PM₁₀ (HR=2.01, 95% CI 1.07 to 3.77) per 10 µg/m³ (p=0.03), and PM_2.5 (HR=7.93, 95% CI 2.93 to 21.33) per 10 µg/m³ (p<0.001).

CONCLUSION

This study suggests that air pollution has a negative impact on IPF outcomes, corroborating the role of ozone on AEs and establishing, for the first time, the potential role of long-term exposure to PM₁₀ and PM_2.5 on overall mortality.

Obstructive sleep apnoea and related comorbidities in incident idiopathic pulmonary fibrosis

The objectives of this prospective study were: 1) to determine the prevalence and determinants of obstructive sleep apnoea (OSA) in patients with newly diagnosed idiopathic pulmonary fibrosis (IPF); 2) to determine whether OSA was associated with cardiovascular disease (CVD) as well as increased oxidative stress and levels of IPF biomarkers in the blood.

A group of 45 patients with newly diagnosed IPF attended polysomnography. The prevalence of CVD and the severity of coronary artery calcification were investigated by high-resolution computed tomography. The levels of 8-hydroxydeoxyguanosine (8-OH-DG) and various IPF biomarkers in the blood were compared between patients with no or mild OSA (apnoea–hypopnoea index (AHI) <15 events·h−1), with moderate OSA (15 ≤AHI <30 events·h−1) and with severe OSA (AHI ≥30 events·h−1).

The prevalence of moderate-to-severe OSA and severe OSA was 62% and 40%, respectively. AHI did not correlate with demographic or physiological data. All patients with severe OSA had a medical history of CVD,versus41.2% and 40% of those with no or mild OSA, or with moderate OSA, respectively (p<0.0001). Ischaemic heart disease (IHD) and moderate-to-severe coronary artery calcifications were strongly associated with severe OSA. The 8-OH-DG and matrix metalloproteinase-7 serum levels were significantly increased in the severe OSA group.

Moderate-to-severe OSA is highly prevalent in incident IPF and severe OSA is strongly associated with the presence of CVD, particularly IHD.

Nonspecific interstitial pneumonia: survival is influenced by the underlying cause

Idiopathic, nonspecific interstitial pneumonia (NSIP) is most often associated with various clinical disorders, including connective tissue diseases (CTDs) and chronic hypersensitivity pneumonitis (cHP). Emerging evidence also suggests that “idiopathic” NSIP may be the lung manifestation of undifferentiated CTD (UCTD). However, whether or not NSIP outcome is influenced by the underlying cause remains uncertain.

This retrospective study included 127 biopsy-proven NSIP patients (65 women, mean±sd age 55±12 years). Survivals were estimated using a Kaplan–Meier curve and compared using the log-rank test. Multivariate analyses were based on a Cox model.

15 (11.8%) patients had cHP, 29 (22.8%) had CTD, 32 (25.2%) satisfied the Kinder criteria for UCTD and 51 (40.1%) had idiopathic NSIP. At the end of follow-up (mean±sd 64±54 months), a difference in survival was observed between aetiological groups (p=0.002). Survival was better for UCTD than for idiopathic NSIP (p=0.020) and similar to that observed for CTD. cHP survival tended to be poorer than that of idiopathic NSIP (p=0.087) and was an independent predictor of mortality (hazard ratio 2.17, 95% CI 1.05–4.47; p=0.035).

NSIP outcome is influenced by its cause. cHP exhibits the highest mortality. UCTD does not differ from CTD supporting the concept of autoimmune NSIP, with a prognosis that is better than that of idiopathic NSIP.

Imbalance of circulating endothelial cells and progenitors in idiopathic pulmonary fibrosis

BACKGROUND

Fibrogenesis during idiopathic pulmonary fibrosis (IPF) is strongly associated with abnormal vascular remodeling. Respective abundance of circulating endothelial cells (CEC) and endothelial progenitor cells (EPC) might reflect the balance between vascular injury and repair and potentially serve as biomarkers of the disease.

OBJECTIVES AND METHODS

We postulated that CEC and EPC subtypes might be differently modulated in IPF. Sixty-four consecutive patients with newly diagnosed IPF were prospectively enrolled and compared to thirteen healthy volunteers. CEC were counted with immunomagnetic CD146-coated beads; progenitors CD34+45(dim)/CD34+133+/CD34+KDR+were assessed through flow cytometry and EPC (colony-forming-units-Endothelial Cells, CFU-EC, and endothelial colonies forming cells, ECFC) were quantified by cell culture assays.

RESULTS

IPF patients were characterized by a marked increase in CEC associated to an EPC defect: both CD34(+)KDR(+) cells and CFU-EC were decreased versus controls. Moreover, in IPF subjects with a low diffusing capacity of the lung for carbon monoxide (DL(CO)) < 40 %, CFU-EC and ECFC were higher compared to those with DL(CO) > 40 %. Finally, ECFC were negatively correlated with DL(CO). During an 18 month follow up, CEC levels increased in patients with exacerbation, including those who died during follow up. Finally, ECFC from patients with exacerbation proliferative potential was strongly increased.

CONCLUSION

IPF is basically associated with both a vascular injury and a repair defect. This study highlights an adaptative process of EPC mobilization in the most severe forms of IPF, that could reflect enhanced homing to the pulmonary vasculature, which clinical consequences remain to be determined.

Progression of idiopathic pulmonary fibrosis: lessons from asymmetrical disease

BACKGROUND

In idiopathic pulmonary fibrosis (IPF) the distribution and spatial-temporal progression of fibrotic changes may be influenced by general or locoregional conditions. From this perspective, patients with asymmetrical disease (AIPF) may be unique.

METHODS

This retrospective study included 32 patients (26 men, mean ± SD age 69 ± 7 years) with AIPF, as defined by an asymmetry ratio (most affected--least affected fibrosis score)/(most affected + least affected fibrosis score) >0.2. The global fibrosis score was the average of the right and left scores. Patients with AIPF were compared with 64 matched controls with symmetrical IPF.

RESULTS

Patients with AIPF did not differ from controls in global fibrosis score and forced vital capacity, but carbon monoxide transfer factor was less decreased (52 ± 19% vs 43 ± 13%, p=0.009). The rate of gastro-oesophageal reflux and acute exacerbations was significantly higher in patients with AIPF (62.5% vs 31.3%, p=0.006 and 46.9% vs 17.2%, p=0.004, respectively). In patients with AIPF the right side was more likely to be involved (62.5%); the median asymmetry ratio was 0.5 (range 0.24-1). Although the global fibrosis score worsened significantly in all 23 patients with AIPF with serial high-resolution CT scans (p<0.0001), pulmonary fibrosis remained asymmetrical in all except three. During follow-up, 15 patients with AIPF experienced 18 acute exacerbations. The first episode was virtually unilateral, occurring in the most affected lung in 10 patients (66.7%). Survival was similar between patients with AIPF and controls.

CONCLUSION

AIPF may be related to locoregional factors including gastro-oesophageal reflux which may be responsible for both disease expansion and the occurrence of acute exacerbations.

[Diagnostic challenges in sarcoidosis]

The diagnostic of sarcoidosis is done when clinical and radiological usual signs are present with nonnecrotizing granuloma and in the absence of any other granulomatous disease. However, if associated with usual manifestations of sarcoidosis and if published similar case reports are available, diagnostic is not excluded by atypical clinical or radiological facts. Chest thin-section hight-resolution computed tomographic scan is very useful to obvious typical findings when chest-X-ray looks unusual. In some cases, achievement of granuloma can be delayed if sarcoidosis does not require any drug. Besides, difficulties exist regarding alternative diagnosis, particularly tuberculosis for patients from endemic countries. Lastly, clinical course manifestations rise to know the discriminate between sarcoidosis, treatment side-effects and others sarcoidosis-associated diseases.