Association of BMI and Change in Weight With Mortality in Patients With Fibrotic Interstitial Lung Disease

BACKGROUND

Mortality risk assessment in interstitial lung disease (ILD) is challenging. Our objective was to determine the prognostic significance of BMI and change in weight in the most common fibrotic ILD subtypes.

RESEARCH QUESTION

Could BMI and weight loss over time be reliable prognostic indicators in patients with fibrotic ILD?

STUDY DESIGN AND METHODS

This observational retrospective multicenter cohort study enrolled patients with fibrotic ILD from the six-center CAnadian REgistry for Pulmonary Fibrosis (CARE-PF, derivation) and the ILD registry at the University of California, San Francisco (UCSF, validation). Patients were subcategorized as underweight (BMI < 18.5), normal weight (BMI 18.5-24.9), overweight (BMI 25-29.9), or obese (BMI > 30). Annual change in weight was calculated for all years of follow-up as the slope of best fit using the least square method based on every available measurement. Separate multivariable analyses evaluated the associations of BMI and change in weight with mortality, adjusting for common prognostic variables.

RESULTS

The derivation and validation cohorts included 1,786 and 1,779 patients, respectively. Compared with patients with normal BMI, mortality was highest in patients who were underweight (hazard ratio [HR], 3.19; 95% CI, 1.88-5.43; P < .001) and was lowest in those who were overweight (HR, 0.52; 95% CI, 0.36-0.75; P < .001) or obese (HR, 0.55; 95%CI, 0.37-0.83; P < .001) in the analysis adjusted for the ILD-GAP (gender, age, physiology) Index. Patients who had a weight loss of at least 2 kg within 1 year had increased risk of death in the subsequent year (HR, 1.41; 95% CI, 1.01-1.97; P = .04) after adjustment for the ILD-GAP Index and baseline BMI category, with a plateau in risk for patients with greater weight loss. Consistent results were observed in the validation cohort.

INTERPRETATION

Both BMI and weight loss are independently associated with 1-year mortality in fibrotic ILD. BMI and weight loss may be clinically useful prognostic indicators in fibrotic ILD.

Integrating Clinical Probability into the Diagnostic Approach to Idiopathic Pulmonary Fibrosis: An International Working Group Perspective

BACKGROUND

When considering the diagnosis of idiopathic pulmonary fibrosis (IPF), experienced clinicians integrate clinical features that help to differentiate IPF from other fibrosing interstitial lung diseases, thus generating a "pre-test" probability of IPF. The aim of this international working group perspective was to summarize these features using a tabulated approach similar to chest HRCT and histopathologic patterns reported in the international guidelines for the diagnosis of IPF, and to help formally incorporate these clinical likelihoods into diagnostic reasoning to facilitate the diagnosis of IPF.

METHODS

The committee group identified factors that influence the clinical likelihood of a diagnosis of IPF, which was categorized as a pre-test clinical probability of IPF into "high" (70-100%), "intermediate" (30-70%), or "low" (0-30%). After integration of radiological and histopathological features, the post-test probability of diagnosis was categorized into "definite" (90-100%), "high confidence" (70-89%), "low confidence" (51-69%), or "low" (0-50%) probability of IPF.

FINDINGS

A conceptual Bayesian framework was created, integrating the clinical likelihood of IPF ("pre-test probability of IPF") with the HRCT pattern, the histopathology pattern when available, and/or the pattern of observed disease behavior into a "post-test probability of IPF". The diagnostic probability of IPF was expressed using an adapted diagnostic ontology for fibrotic interstitial lung diseases.

INTERPRETATION

The present approach will help incorporate the clinical judgement into the diagnosis of IPF, thus facilitating the application of IPF diagnostic guidelines and, ultimately improving diagnostic confidence and reducing the need for invasive diagnostic techniques.

Association of BMI with pulmonary function, functional capacity, symptoms, and quality of life in ILD

Obesity is a health epidemic associated with greater morbidity and mortality in the general population. Mass loading of the thorax from obesity leads to a restrictive pulmonary defect that reduces lung capacity in obese individuals without pulmonary disease, and may exacerbate the restrictive pulmonary physiology that is characteristic of interstitial lung disease (ILD). The purpose of this study was to test the association of body mass index (BMI) with pulmonary function, functional capacity, and patient-reported outcomes (dyspnea and quality of life) in patients with ILD. We analyzed 3169 patients with fibrotic ILD from the Canadian Registry for Pulmonary Fibrosis. Patients were subcategorized as underweight (BMI<18.5 kg/m2), normal weight (18.5≤BMI<25), overweight (25≤BMI<30), obese I (30≤BMI<35), obese II (35≤BMI<40), and obese III (BMI>40). Analysis was performed using a linear regression with adjustment for common prognostic variables. Overweight and obese BMI categories were associated with worse pulmonary function, functional capacity, dyspnea, and quality of life compared to normal weight. This is likely a result of mass loading on the thorax, and we speculate that intentional weight-loss may improve lung function and functional capacity in obese patients with fibrotic ILD. The underweight BMI category was also associated with worse functional capacity compared to normal weight, which may reflect greater disease severity or the presence of other comorbidities. Future work should explore the clinical utility of BMI to improve patient outcomes.

Detection and Early Referral of Patients With Interstitial Lung Abnormalities: An Expert Survey Initiative

BACKGROUND

Interstitial lung abnormalities (ILA) may represent undiagnosed early-stage or subclinical interstitial lung disease (ILD). ILA are often observed incidentally in patients who subsequently develop clinically overt ILD. There is limited information on consensus definitions for, and the appropriate evaluation of, ILA. Early recognition of patients with ILD remains challenging, yet critically important. Expert consensus could inform early recognition and referral.

RESEARCH QUESTION

Can consensus-based expert recommendations be identified to guide clinicians in the recognition, referral, and follow-up of patients with or at risk of developing early ILDs?

STUDY DESIGN AND METHODS

Pulmonologists and radiologists with expertise in ILD participated in two iterative rounds of surveys. The surveys aimed to establish consensus regarding ILA reporting, identification of patients with ILA, and identification of populations that might benefit from screening for ILD. Recommended referral criteria and follow-up processes were also addressed. Threshold for consensus was defined a priori as ≥ 75% agreement or disagreement.

RESULTS

Fifty-five experts were invited and 44 participated; consensus was reached on 39 of 85 questions. The following clinically important statements achieved consensus: honeycombing and traction bronchiectasis or bronchiolectasis indicate potentially progressive ILD; honeycombing detected during lung cancer screening should be reported as potentially significant (eg, with the Lung CT Screening Reporting and Data System "S-modifier" [Lung-RADS; which indicates clinically significant or potentially significant noncancer findings]), recommending referral to a pulmonologist in the radiology report; high-resolution CT imaging and full pulmonary function tests should be ordered if nondependent subpleural reticulation, traction bronchiectasis, honeycombing, centrilobular ground-glass nodules, or patchy ground-glass opacity are observed on CT imaging; patients with honeycombing or traction bronchiectasis should be referred to a pulmonologist irrespective of diffusion capacity values; and patients with systemic sclerosis should be screened with pulmonary function tests for early-stage ILD.

INTERPRETATION

Guidance was established for identifying clinically relevant ILA, subsequent referral, and follow-up. These results lay the foundation for developing practical guidance on managing patients with ILA.

Sex and gender in interstitial lung diseases

Sex and gender differences influence key domains of research, lung health, healthcare access and healthcare delivery. In interstitial lung diseases (ILDs), mouse models of pulmonary fibrosis are clearly influenced by sex hormones. Additionally, short telomeres, a biomarker of telomere regulation gene mutations, are impacted by sex, while heritability unexplained by genetic variation may be attributable to gendered environmental factors that drive epigenetic control. Diseases like idiopathic pulmonary fibrosis, hypersensitivity pneumonitis, occupational ILDs, connective tissue-associated ILDs and lymphangioleiomyomatosis have different prevalence and prognosis between men and women. These differences arise from a complex interplay between biological sex and sociocultural gender influencing genetics, epigenomic modifiers, hormones, immune function, response to treatment and interaction with healthcare systems. Much work remains to be done to systematically integrate sex and gender analysis into relevant domains of science and clinical care in ILD, from strategic considerations for establishing research priorities to guidelines for establishing best clinical practices. Accounting for sex and gender in ILD is essential to the practice of individualised, patient-centred medicine.

Relative environmental and social disadvantage in patients with idiopathic pulmonary fibrosis

BACKGROUND

Air pollution exposure is associated with disease severity, progression and mortality in patients with idiopathic pulmonary fibrosis (IPF). Combined impacts of environmental and socioeconomic factors on outcomes in patients with IPF are unknown. The objectives of this study were to characterise the relationships between relative environmental and social disadvantage with clinical outcomes in patients with IPF.

METHODS

Patients with IPF were identified from a longitudinal database at University of California, San Francisco. Residential addresses were geocoded and linked to the CalEnviroScreen 3.0 (CES), a tool that quantifies environmental burden in California communities, combining population, environmental and pollution vulnerability into individual and composite scores (higher scores indicating greater disadvantage). Unadjusted and adjusted linear and logistic regression and Fine and Gray proportional hazards models were used.

RESULTS

603 patients were included. Higher CES was associated with lower baseline forced vital capacity (β=-0.073, 95% CI -0.13 to -0.02; p=0.006) and diffusion capacity of the lung for carbon monoxide (β=-0.11, 95% CI -0.16 to -0.06; p<0.001). Patients in the highest population vulnerability quartile were less likely to be on antifibrotic therapy (OR=0.33; 95% CI 0.18 to 0.60; p=0.001) at time of enrolment, compared with those in the lowest quartile. An association between CES and mortality was suggested, but sensitivity analyses demonstrated inconsistent results. Relative disadvantage of the study cohort appeared lower compared with the general population.

CONCLUSIONS

Higher environmental exposures and vulnerability were associated with lower baseline lung function and lower antifibrotic use, suggesting that relative socioenvironmental disadvantage has meaningful impacts on patients with IPF.

Effect of continued antifibrotic therapy after forced vital capacity decline in patients with idiopathic pulmonary fibrosis; a real world multicenter cohort study

RATIONALE

Longitudinal data on the impact of continued, switched or discontinued antifibrotic therapy in patients with idiopathic pulmonary fibrosis (IPF) who have disease progression is needed.

OBJECTIVE

We hypothesized that ongoing antifibrotic use (versus discontinuation) in the setting of forced vital capacity (FVC) decline would be associated with less future decline and lower likelihood of a composite outcome of FVC decline, lung transplant, or death.

METHODS

We performed a multicenter cohort study using data from the Canadian Registry for Pulmonary Fibrosis in patients with IPF with FVC decline ≥10% over 6 months on antifibrotic therapy. The association of continued, switched or discontinued therapy with (1) further change in FVC and (2) a composite of FVC decline ≥10%, transplant, or death, in the subsequent 6 months, was assessed using adjusted linear and logistic regression modelling, respectively. Generalized estimating equations accounted for repeated observations per patient.

RESULTS

165 patients had a decline in FVC ≥10% over 6 months while receiving antifibrotic therapy. Compared to continued use, antifibrotic discontinuation after FVC decline was associated with greater additional FVC decline (-207 mL 95%CI -353 to -62, p = 0.005) and higher odds of FVC decline ≥10%, transplant, or death (odds ratio 12.2 95%CI 1.2 to 130.5, p = 0.04). There was no difference between continued versus switched antifibrotic therapy.

CONCLUSIONS

Ongoing antifibrotic therapy in the setting of FVC decline is associated with less future FVC decline and lower odds of FVC decline ≥10%, transplant, or death in a real-world cohort of IPF.

Malignancy Risk Associated with Mycophenolate Mofetil or Azathioprine in Patients with Fibrotic Interstitial Lung Disease

Some of these results were presented in abstract form at the 2021 American Thoracic Society International Conference, May 2021.

Neighborhood-level Disadvantage Impacts on Patients with Fibrotic Interstitial Lung Disease

RATIONALE

Fibrotic interstitial lung diseases (fILDs) represent a group of pathologic entities characterized by scarring of the lungs and high morbidity and mortality. Research investigating how socioeconomic and residential factors impact outcomes in patients with fILDs is lacking.

OBJECTIVES

To determine the association between neighborhood-level disadvantage and presentation severity, disease progression, lung transplant, and mortality in patients with fILD from the United States (U.S.) and Canada.

METHODS

Multi-center, international, prospective cohort study of 4729 patients with fILD from one U.S. and eight Canadian ILD registry sites. Neighborhood-level disadvantage was measured by the area deprivation index (ADI) in the U.S. and the Canadian Index of Multiple Deprivation (CIMD) in Canada.

MEASUREMENTS AND MAIN RESULTS

In the U.S., but not Canadian cohort, patients with fILD living in neighborhoods with the greatest disadvantage (top quartile) experience the highest risk of mortality (hazard ratio=1.51, p=0.002) and in subgroups of patients with idiopathic pulmonary fibrosis (IPF), the top quartile of disadvantage experienced the lowest odds of lung transplant (odds ratio=0.46, p=0.04). Greater disadvantage was associated with reduced baseline diffusion capacity for carbon monoxide (DLCO) in both cohorts, but it was not associated with baseline forced vital capacity (FVC) or FVC or DLCO decline in either cohort.

CONCLUSIONS

Patients with fILD who live in areas with greater neighborhood-level disadvantage in the U.S. experience higher mortality, and patients with IPF experience lower odds of lung transplant. These disparities are not seen in Canadian patients, which may indicate differences in access to care between the U.S. and Canada.

Treatment of fibrotic interstitial lung disease: current approaches and future directions

Fibrotic interstitial lung disease (ILD) represents a large group of pulmonary disorders that are often progressive and associated with high morbidity and early mortality. Important advancements in the past 10 years have enabled a better understanding, characterisation, and treatment of these diseases. This Series paper summarises the current approach to treatment of fibrotic ILDs, both pharmacological and non-pharmacological, including recent discoveries and practice-changing clinical trials. We further outline controversies and challenges, with discussion of evolving concepts and future research directions.

Worldwide experiences and opinions of healthcare providers on eHealth for patients with interstitial lung diseases in the COVID-19 era

Interstitial lung diseases (ILD) comprise a group of pulmonary diseases characterised by diffuse parenchymal abnormalities, which can lead to irreversible pulmonary fibrosis [1].

The #COVID19 pandemic has led to an increase in the use of eHealth for patients with interstitial lung disease. Healthcare providers worldwide are positive towards further implementation of eHealth for research and clinical practice.https://bit.ly/3h2545M

Survival after inpatient or outpatient pulmonary rehabilitation in patients with fibrotic interstitial lung disease: a multicentre retrospective cohort study

BACKGROUND

The impact of pulmonary rehabilitation (PR) on survival in patients with fibrotic interstitial lung disease (ILD) is unknown. Given the challenges conducting a large randomised controlled trial, we aimed to determine whether improvement in 6-minute walk distance (6MWD) was associated with better survival.

METHODS

This retrospective, international cohort study included patients with fibrotic ILD participating in either inpatient or outpatient PR at 12 sites in 5 countries. Multivariable models were used to estimate the association between change in 6MWD and time to death or lung transplantation accounting for clustering by centre and other confounders.

RESULTS

701 participants (445 men and 256 women) with fibrotic ILD were included. The mean±SD ages of the 196 inpatients and 505 outpatients were 70±11 and 69±12 years, respectively. Baseline/changes in 6MWD were 262±128/55±83 m for inpatients and 358±125/34±65 m for outpatients. Improvement in 6MWD during PR was associated with lower hazard rates for death or lung transplant on adjusted analysis for both inpatient (HR per 10 m 0.94, 95% CI 0.91 to 0.97, p<0.001) and outpatient PR (HR 0.97, 95% CI 0.95 to 1.00, p=0.042). Participation in ≥80% of planned outpatient PR sessions was associated with a 33% lower risk of death (95% CI 0.49% to 0.92%).

CONCLUSIONS

Patients with fibrotic ILD who improved physical performance during PR had better survival compared with those who did not improve performance. Confirmation of these hypothesis-generating findings in a randomised controlled trial would be required to definitely change clinical practice, and would further support efforts to improve availability of PR for patients with fibrotic ILD.

Management of Fibrotic Hypersensitivity Pneumonitis

Fibrotic hypersensitivity pneumonitis (fHP) is a chronic, often progressive fibrosing form of interstitial lung disease caused by inhaled antigenic exposures. fHP can lead to impaired respiratory function, reduced disease-related quality of life, and early mortality. Management of fHP should start with exposure remediation where possible, with systemic immunosuppression and antifibrotic therapy considered in patients with symptomatic or progressive disease. Nonpharmacologic and supportive management should be offered and, in cases of treatment-resistant, progressive illness, lung transplant should be considered.

Validation and minimum important difference of the UCSD Shortness of Breath Questionnaire in fibrotic interstitial lung disease

RATIONALE

The University of California, San Diego Shortness of Breath Questionnaire (UCSDSOBQ) is a frequently used domain-specific dyspnea questionnaire; however, there is little information available regarding its use and minimum important difference (MID) in fibrotic interstitial lung disease (ILD). We aimed to describe the key performance characteristics of the UCSDSOBQ in this population.

METHODS

UCSDSOBQ scores and selected anchors were measured in 1933 patients from the prospective multi-center Canadian Registry for Pulmonary Fibrosis. Anchors included the St. George's Respiratory Questionnaire (SGRQ), European Quality of Life 5 Dimensions 5 Levels questionnaire (EQ-5D-5L) and EQ visual analogue scale (EQ-VAS), percent-predicted forced vital capacity (FVC%), diffusing capacity of the lung for carbon monoxide (DLCO%), and 6-min walk distance (6MWD). Concurrent validity, internal consistency, ceiling and floor effects, and responsiveness were assessed, followed by estimation of the MID by anchor-based (linear regression) and distribution-based methods (standard error of measurement).

RESULTS

The UCSDSOBQ had a high level of internal consistency (Cronbach's alpha = 0.97), no obvious floor or ceiling effect, strong correlations with SGRQ, EQ-5D-5L, and EQ-VAS (|r| > 0.5), and moderate correlations with FVC%, DLCO%, and 6MWD (0.3 < |r| < 0.5). The MID estimate for UCSDSOBQ was 5 points (1-8) for the anchor-based method, and 4.5 points for the distribution-based method.

CONCLUSION

This study demonstrates the validity of UCSDSOBQ in a large and heterogeneous population of patients with fibrotic ILD, and provides a robust MID estimate of 5-8 points.

Home spirometry in patients with idiopathic pulmonary fibrosis: data from the INMARK trial

Background

Data from the INMARK trial were used to investigate the feasibility and validity of home spirometry as a measure of lung function decline in patients with idiopathic pulmonary fibrosis (IPF).

Methods

Subjects with IPF and preserved forced vital capacity (FVC) were randomised to receive nintedanib or placebo for 12 weeks followed by open-label nintedanib for 40 weeks. Clinic spirometry was conducted at baseline and weeks 4, 8, 12, 16, 20, 24, 36 and 52. Subjects were asked to perform home spirometry at least once a week and ideally daily. Correlations between home- and clinic-measured FVC and rates of change in FVC were assessed using Pearson correlation coefficients.

Results

In total, 346 subjects were treated. Mean adherence to weekly home spirometry decreased over time but remained above 75% in every 4-week period. Over 52 weeks, mean adherence was 86%. Variability in change from baseline in FVC was greater when measured by home rather than clinic spirometry. Strong correlations were observed between home- and clinic-measured FVC at all time-points (r=0.72–0.84), but correlations between home- and clinic-measured rates of change in FVC were weak (r=0.26 for rate of decline in FVC over 52 weeks).

Conclusion

Home spirometry was a feasible and valid measure of lung function in patients with IPF and preserved FVC, but estimates of the rate of FVC decline obtained using home spirometry were poorly correlated with those based on clinic spirometry.

In a 52-week study in 346 subjects with idiopathic pulmonary fibrosis, mean adherence to weekly home spirometry was 86%. Estimates of the rate of decline in forced vital capacity obtained using home and clinic spirometry were poorly correlated.https://bit.ly/2WjIQ4b

Social Media Content of Idiopathic Pulmonary Fibrosis Groups and Pages on Facebook: Cross-sectional Analysis

Background

Patients use Facebook as a resource for medical information. We analyzed posts on idiopathic pulmonary fibrosis (IPF)-related Facebook groups and pages for the presence of guideline content, user engagement, and usefulness.

Objective

The objective of this study was to describe and analyze posts from Facebook groups and pages that primarily focus on IPF-related content.

Methods

Cross-sectional analysis was performed on a single date, identifying Facebook groups and pages resulting from separately searching “IPF” and “idiopathic pulmonary fibrosis.” For inclusion, groups and pages needed to meet either search term and be in English, publicly available, and relevant to IPF. Every 10th post was assessed for general characteristics, source, focus, and user engagement metrics. Posts were analyzed for presence of IPF guideline content, useful scientific information (eg, scientific publications), useful support information (eg, information about support groups), and potentially harmful information.

Results

Eligibility criteria were met by 12 groups and 27 pages, leading to analysis of 523 posts. Of these, 42% contained guideline content, 24% provided useful support, 20% provided useful scientific information, and 5% contained potentially harmful information. The most common post source was nonmedical users (85%). Posts most frequently focused on IPF-related news (29%). Posts containing any guideline content had fewer likes or comments and a higher likelihood of containing potentially harmful content. Posts containing useful supportive information had more likes, shares, and comments.

Conclusions

Facebook contains useful information about IPF, but posts with misinformation and less guideline content have higher user engagement, making them more visible. Identifying ways to help patients with IPF discriminate between useful and harmful information on Facebook and other social media platforms is an important task for health care professionals.

Exposures and associations with clinical phenotypes in hypersensitivity pneumonitis: A scoping review

Antigen identification is important for establishing a confident diagnosis of hypersensitivity pneumonitis (HP). There are no systematically curated lists of HP-associated exposures that inform clinical relevance or disease phenotype. We sought to systematically identify all reported causes of HP in the literature and evaluate their clinical relevance. A scoping review was performed to identify all publications describing HP cases and their associated exposures (even if unknown) from Jan 1990-June 2020. Frequencies of exposures and meta-analysis of proportions for registry-based studies were determined for specific exposure categories, and associations with fibrotic and non-fibrotic HP were assessed. 24,138 publications were identified, with 967 publications included in the final analysis, representing 62 unique exposures associated with HP. Certain exposures were more frequently reported than others, including birds (comprising 32% of HP cases in registry-based studies) and mould (17% registry study HP cases). Antigen-indeterminate HP comprised 15-24% of registry-based studies. Limited data found contaminated metal-working fluids, isocyanate exposure, and hot tub lung were rarely associated with fibrotic features, whereas antigen-indeterminate HP cases were more frequently associated with fibrosis. There was heterogeneity in HP case definition and how causative exposures were identified. We identified 62 unique exposures associated with HP, with specific exposures associated with clinical phenotypes. These data may inform clinical assessment and the development of questionnaires to identify antigens in the diagnostic evaluation of suspected HP. OPEN SCIENCES FRAMEWORK REGISTRATION: osf.io/4aq5m.

Description of a Multi-faceted COVID-19 Pandemic Physician Workforce Plan at a Multi-site Academic Health System

BACKGROUND

The evolving COVID-19 pandemic has and continues to present a threat to health system capacity. Rapidly expanding an existing acute care physician workforce is critical to pandemic response planning in large urban academic health systems.

INTERVENTION

The Medical Emergency-Pandemic Operations Command (MEOC)-a multi-specialty team of physicians, operational leaders, and support staff within an academic Department of Medicine in Calgary, Canada-partnered with its provincial health system to rapidly develop a comprehensive, scalable pandemic physician workforce plan for non-ventilated inpatients with COVID-19 across multiple hospitals. The MEOC Pandemic Plan comprised seven components, each with unique structure and processes.

METHODS

In this manuscript, we describe MEOC's Pandemic Plan that was designed and implemented from March to May 2020 and re-escalated in October 2020. We report on the plan's structure and process, early implementation outcomes, and unforeseen challenges. Data sources included MEOC documents, health system, public health, and physician engagement implementation data.

KEY RESULTS

From March 5 to October 26, 2020, 427 patients were admitted to COVID-19 units in Calgary hospitals. In the initial implementation period (March-May 2020), MEOC communications reached over 2500 physicians, leading to 1446 physicians volunteering to provide care on COVID-19 units. Of these, 234 physicians signed up for hospital shifts, and 227 physicians received in-person personal protective equipment simulation training. Ninety-three physicians were deployed on COVID-19 units at four large acute care hospitals. The resurgence of cases in September 2020 has prompted re-escalation including re-activation of COVID-19 units.

CONCLUSIONS

MEOC leveraged an academic health system partnership to rapidly design, implement, and refine a comprehensive, scalable COVID-19 acute care physician workforce plan whose components are readily applicable across jurisdictions or healthcare crises. This description may guide other institutions responding to COVID-19 and future health emergencies.