High prevalence of interstitial lung abnormalities in middle-aged never-smokers.

Background: Interstitial lung abnormalities (ILA) are incidental findings on chest computed tomography (CT). These patterns can present at an early stage of fibrotic lung disease. Our aim was to estimate the prevalence of ILA in the Swedish population, in particular in never-smokers, and find out its association with demographics, comorbidities and symptoms. Methods: Participants were recruited to the Swedish CArdioPulmonary BioImage Study (SCAPIS), a population-based survey including men and women aged 50-64 years performed at six university hospitals in Sweden. CT scan, spirometry and questionnaires were performed. ILA were defined as cysts, ground-glass opacities, reticular abnormality, bronchiectasis and honeycombing. Findings: Out of 29 521 participants, 14 487 were never-smokers and 14 380 were men. In the whole population, 2870 (9.7%) had ILA of which 134 (0.5%) were fibrotic. In never-smokers, the prevalence was 7.9% of which 0.3% were fibrotic. In the whole population, age, smoking history, chronic bronchitis, cancer, coronary artery calcium score and high-sensitive C-reactive protein were associated with ILA. Both ILA and fibrotic ILA were associated with restrictive spirometric pattern and impaired diffusing capacity of the lung for carbon monoxide. However, individuals with ILA did not report more symptoms compared with individuals without ILA. Interpretation: ILA are common in a middle-aged Swedish population including never-smokers. ILA may be at risk of being underdiagnosed among never-smokers since they are not a target for screening.

Baseline characteristics and survival of patients of idiopathic pulmonary fibrosis: a longitudinal analysis of the Swedish IPF Registry.

BACKGROUND: Observational data under real-life conditions in idiopathic pulmonary fibrosis (IPF) is scarce. We explored anti-fibrotic treatment, disease severity and phenotypes in patients with IPF from the Swedish IPF Registry (SIPFR). METHODS: Patients enrolled between September 2014 and April 2020 and followed ≥ 6 months were investigated. Demographics, comorbidities, lung function, composite variables, six-minute walking test (6MWT), quality of life, and anti-fibrotic therapy were evaluated. Agreements between classification of mild physiological impairment (defined as gender-age-physiology (GAP) stage 1) with physiological and composite measures of severity was assessed using kappa values and their impact on mortality with hazard ratios. The factor analysis and the two-step cluster analysis were used to identify phenotypes. Univariate and multivariable survival analyses were performed between variables or groups. RESULTS: Among 662 patients with baseline data (median age 72.7 years, 74.0% males), 480 had a follow up ≥ 6 months with a 5 year survival rate of 48%. Lung function, 6MWT, age, and BMI were predictors of survival. Patients who received anti-fibrotic treatment ≥ 6 months had better survival compared to untreated patients [p = 0.007, HR (95% CI): 1.797 (1.173-2.753)] after adjustment of age, gender, BMI, smoking status, forced vital capacity (FVC) and diffusion capacity of carbon monoxide (DLCO). Patients with mild physiological impairment (GAP stage 1, composite physiological index (CPI) ≤ 45, DLCO ≥ 55%, FVC ≥ 75%, and total lung capacity (TLC) ≥ 65%, respectively) had better survival, after adjustment for age, gender, BMI and smoking status and treatment. Patients in cluster 1 had the worst survival and consisted mainly of male patients with moderate-severe disease and an increased prevalence of heart diseases at baseline; Cluster 2 was characterized by mild disease with more than 50% females and few comorbidities, and had the best survival; Cluster 3 were younger, with moderate-severe disease and had few comorbidities. CONCLUSION: Disease severity, phenotypes, and anti-fibrotic treatment are closely associated with the outcome in IPF, with treated patients surviving longer. Phenotypes may contribute to predicting outcomes of patients with IPF and suggest the patients' need for special management, whereas single or composite variables have some limitations as disease predictors.

Gender differences at presentation of idiopathic pulmonary fibrosis in Sweden.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a disease with poor prognosis mainly affecting males. Differences in clinical presentation between genders may be important both for the diagnostic work-up and for follow-up. In the present study, we therefore explored potential gender differences at presentation in a Swedish cohort of IPF-patients. METHODS: We studied patients included in the Swedish IPF- registry over a three-year period from its launch in 2014. A cross-sectional analysis was performed for data concerning demographics, lung function, 6- min walking test (6MWT) and quality of life (QoL) (King's Brief Interstitial Lung Disease (K-BILD) score). RESULTS: Three hundred forty- eight patients (250 (72%) males, 98 (28%) females, median age 72 years in both genders) were included in the registry during the study period. Smoking history (N = 169 (68%) vs. N = 53 (54%), p < 0.05), baseline lung function (Forced vital capacity, % of predicted (FVC%): 68.9% ± 14.4 vs. 73.0% ± 17.7, p < 0.05; Total lung capacity, % of predicted (TLC%): 62.2% ± 11.8 vs. 68.6% ± 11.3%, p < 0.001) were significantly different at presentation between males and females, respectively. Comorbidities such as coronary artery disease (OR: 3.5-95% CI: 1.6-7.6) and other cardiovascular diseases (including atrial fibrillation and heart failure) (OR: 3.8-95% CI: 1.9-7.8) also showed significant differences between the genders. The K- BILD showed poor quality of life, but no difference was found between genders in total score (54 ± 11 vs. 54 ± 10, p = 0.61 in males vs. females, respectively). CONCLUSIONS: This study shows that female patients with IPF have a more preserved lung function than males at inclusion, while males have a significant burden of cardiovascular comorbidities. However, QoL and results on the 6MWT did not differ between the groups. These gender differences may be of importance both at diagnosis and follow- up of patients with IPF.

An Atypical Case of Idiopathic Pulmonary Fibrosis in a Patient from Africa.

A 39 years old African man presented with fatigue, loss of weight and night sweats; radiology showed a possible usual interstitial pneumonia pattern. The patient missed follow-up visits, and presented again after 3 years with productive cough and general illness. Pulmonary function tests showed a decline of FVC compared to a previous investigation. The CT scans showed progression of the interstitial lung disease, and a multidisciplinary conference recommended to proceed with a surgical lung biopsy. Histopathology showed an atypical pattern, with bronchiolar metaplasia. A new multidisciplinary conference made a diagnosis of IPF, and the patient was treated with antifibrotic drugs with a good effect, reaching stability of lung function. This case report highlights the need to improve knowledge and to better characterize rare pulmonary diseases, and especially IPF, among African patients.

Delay and inequalities in the treatment of idiopathic pulmonary fibrosis: the case of two Nordic countries.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is characterized by progressive loss of lung function with high mortality within the first 5 years from diagnosis. In 2011-2014, two drugs, pirfenidone and nintedanib, have been approved worldwide for prevention of IPF progression. National IPF-registries have been established in both Finland and Sweden. Our study explored potential differences in the care of IPF in these two countries. METHODS: Patients included consecutively in the Finnish and Swedish IPF-registries from January 1, 2014 through December 31, 2016 were included in the study. Data on demographics and lung function at the time of inclusion were collected. Access to antifibrotic drugs and data on disease outcomes, mortality and the proportion of patients who underwent lung transplantation, was collected during a 3-year follow up. RESULTS: One-hundred and fifty-two patients from the Finnish and 160 patients from the Swedish IPF-cohorts were included in the study. At inclusion, Finnish patients were significantly older than the Swedish patients (74.6 years vs 72.5 years, p = 0.017). The proportion of non-smokers was significantly higher in the Finnish cohort (41.7% vs 26.9%, p = 0.007). Forced vital capacity (FVC), % of predicted (78.2 vs 71.7 for Finnish and Swedish patients, respectively, p = 0.01) and diffusion capacity for carbon monoxide (DLCO), % of predicted (53.3 vs 48.2 for Finnish and Swedish patients, respectively, p = 0.002) were significantly higher in the Finnish cohort compared to the Swedish cohort at the time of inclusion. During the 3-year follow up period, 45 (29.6%) Finnish and 111 (69.4%) Swedish patients, respectively, were initiated on treatment with an antifibrotic drug (pirfenidone or nintedanib) (p <  0.001). When comparing possible determinants of treatment, patients with higher FVC % were less likely to start antifibrotic drugs (OR 0.96, 95%CI 0.93-1.00, p <  0.024). To be resident in Sweden was the main determinant for receiving antifibrotic drugs (OR 5.48, 95%CI 2.65-11.33, p < 0.0001). No significant difference in number of deaths and lung transplantation during the follow up period was found. CONCLUSIONS: This study highlights differences concerning how IPF patients are treated in Finland and Sweden. How these differences will influence the long-term outcome of these patients is unknown.