Statins: cause of fibrosis or the opposite? Effect of cardiovascular drugs in idiopathic pulmonary fibrosis

Association between statin use and the risk for idiopathic pulmonary fibrosis and its prognosis: a nationwide, population-based study

Given the pleiotropic effects of statins beyond their lipid-lowering effects, there have been attempts to evaluate the role of statin therapy in IPF, but they have shown inconclusive results. Data from the National Health Insurance Service (NHIS) database of South Korea were used to investigate the effects of statin therapy on IPF. The IPF cohort consisted of a total of 10,568 patients who were newly diagnosed with IPF between 2010 and 2017. These patients were then matched in a 1:3 ratio to 31,704 subjects from a control cohort without IPF, with matching based on age and sex. A case-control study was performed to evaluate the association between statin use and the risk for IPF, and the multivariable analysis revealed that statin use was associated with a lower risk for IPF (adjusted OR 0.847, 95% CI 0.800-0.898). Using the IPF cohort, we also evaluated whether statin use at the time of diagnosis was associated with future clinical outcomes. The statin use at the time of IPF diagnosis was associated with improved overall survival (adjusted HR 0.779, 95% CI 0.709-0.856). Further prospective studies are needed to clarify the role of statin therapy in IPF.

Statins and thyroid eye disease (TED): a systematic review

PURPOSE

Thyroid eye disease (TED) is the foremost extrathyroidal manifestation of Graves' disease (GD). Currently, available treatments do not entirely prevent the long-term consequences of TED and have distinct disadvantages. Therefore, this systematic review explored available evidence regarding the efficacy of statins in preventing and treating TED.

METHODS

Relevant studies investigating statin usage in patients with GD or TED were identified by searching Medline (Pubmed and Ovid), Scopus, Web of Science, ProQuest, and Cochrane Library databases (from the database inception to September 2023). The review was done according to the PRISMA statement. Web searching was done independently by two investigators. Two researchers independently extracted the data, and any disagreement was adjudicated by consensus. Based on the study design, the studies' quality appraisal was done using the Newcastle-Ottawa Scale (NOS) and Version 2 of the Cochrane risk-of-bias tool (RoB2).

RESULTS

The literature search identified 145 publications, of which four met the inclusion criteria (Three retrospective cohort studies and one randomized clinical trial) and were reviewed in full text. The two retrospective cohort studies demonstrated the beneficial effects of statins on TED in newly diagnosed GD Stein et al. showed that statins, regardless of the type, prevent or delay TED (HR: 0.74 (0.65-0.84)), especially in men or treatment duration of more than one year. Nilsson et al. fascinatingly revealed that at least 60 days of statin usage in the preceding year could decrease the risk of TED development by around 40%. One RCT showed a higher treatment response for active moderate-to-severe TED in patients with hypercholesterolemia who took atorvastatin 20 mg in addition to ivGC for 24 weeks without any increase in serious side effects. The retrospective study revealed that the need for reconstructive surgery was reduced in patients with severe TED who received statin therapy.

CONCLUSION

Statin therapy could be a potential adjunctive modality for preventing and treating TED.

TRIAL REGISTRATION

PROSPERO registration number: CRD42022315522.

Progress in understanding and treating idiopathic pulmonary fibrosis: recent insights and emerging therapies

Idiopathic pulmonary fibrosis (IPF) is a long-lasting, continuously advancing, and irrevocable interstitial lung disorder with an obscure origin and inadequately comprehended pathological mechanisms. Despite the intricate and uncharted causes and pathways of IPF, the scholarly consensus upholds that the transformation of fibroblasts into myofibroblasts-instigated by injury to the alveolar epithelial cells-and the disproportionate accumulation of extracellular matrix (ECM) components, such as collagen, are integral to IPF's progression. The introduction of two novel anti-fibrotic medications, pirfenidone and nintedanib, have exhibited efficacy in decelerating the ongoing degradation of lung function, lessening hospitalization risk, and postponing exacerbations among IPF patients. Nonetheless, these pharmacological interventions do not present a definitive solution to IPF, positioning lung transplantation as the solitary potential curative measure in contemporary medical practice. A host of innovative therapeutic strategies are presently under rigorous scrutiny. This comprehensive review encapsulates the recent advancements in IPF research, spanning from diagnosis and etiology to pathological mechanisms, and introduces a discussion on nascent therapeutic methodologies currently in the pipeline.

Prostaglandin E2 (PGE2) and Roflumilast Involvement in IPF Progression

The ECM propagates processes in idiopathic pulmonary fibrosis (IPF), leading to progressive lung scarring. We established an IPF-conditioned matrix (IPF-CM) system as a platform for testing drug candidates. Here, we tested the involvement of a PGE2 and PDE4 inhibitor, Roflumilast, in the IPF-CM system. Primary normal/IPF tissue-derived human lung fibroblasts (N/IPF-HLFs) were cultured on Matrigel and then removed to create the IPF-CM. N-HLFs were exposed to the IPF-CM/N-CM with/without PGE2 (1 nM) and Roflumilast (1 µM) for 24 h. The effect of the IPF-CM on cell phenotype and pro-fibrotic gene expression was tested. In addition, electronic records of 107 patients with up to 15-year follow-up were retrospectively reviewed. Patients were defined as slow/rapid progressors using forced vital capacity (FVC) annual decline. Medication exposure was examined. N-HLFs cultured on IPF-CM were arranged in large aggregates as a result of increased proliferation, migration and differentiation. A PGE2 and Roflumilast combination blocked the large aggregate formation induced by the IPF-CM (p < 0.001) as well as cell migration, proliferation, and pro-fibrotic gene expression. A review of patient records showed that significantly more slow-progressing patients were exposed to NSAIDs (p = 0.003). PGE2/PDE4 signaling may be involved in IPF progression. These findings should be further studied.

Association between the use of statins and risk of interstitial lung disease/idiopathic pulmonary fibrosis: time-dependent analysis of population-based nationwide data

BACKGROUND

We aimed to study whether statin use is associated with lowering the development of interstitial lung disease (ILD) and idiopathic pulmonary fibrosis (IPF).

METHODS

The study population was the Korean National Health Insurance Service-Health Screening Cohort. ILD and IPF cases were identified using diagnosis codes (J84.1 for ILD and J84.1A as a special code for IPF) based on the International Classification of Diseases, 10th Revision. The study participants were followed up from 1 January 2004 to 31 December 2015. Statin use was defined by the cumulative defined daily dose (cDDD) per 2-year interval and participants were categorised into never-users, <182.5, 182.5-365.0, 365.0-547.5 and ≥547.5 by cDDD. A Cox regression was used to fit models with time-dependent variables of statin use.

RESULTS

Incidence rates for ILD with and without statin use were 20.0 and 44.8 per 100 000 person-years, respectively, and those for IPF were 15.6 and 19.3 per 100 000 person-years, respectively. The use of statins was independently associated with a lower incidence of ILD and IPF in a dose-response manner (p-values for trend <0.001). ILD showed respective adjusted hazard ratios (aHRs) of 1.02 (95% CI 0.87-1.20), 0.60 (95% CI 0.47-0.77), 0.27 (95% CI 0.16-0.45) and 0.24 (95% CI 0.13-0.42) according to the increasing category of statin use compared with never-users. IPF showed respective aHRs of 1.29 (95% CI 1.07-1.57), 0.74 (95% CI 0.57-0.96), 0.40 (95% CI 0.25-0.64) and 0.21 (95% CI 0.11-0.41).

CONCLUSION

A population-based cohort analysis found that statin use is independently associated with a decreased risk of ILD and IPF in a dose-response manner.

Anti-fibrotic effects of statin drugs: a review of evidence and mechanisms

Fibrosis is a pathological repair process common among organs, that responds to damage by replacement of tissue with non-functional connective tissue. Despite the widespread prevalence of tissue fibrosis, manifesting in numerous disease states across myriad organs, therapeutic modalities to prevent or alleviate fibrosis are severely lacking in quantity and efficacy. Alongside development of new drugs, repurposing of existing drugs may be a complementary strategy to elect anti-fibrotic compounds for pharmacologic treatment of tissue fibrosis. Drug repurposing can provide key advantages to de novo drug discovery, harnessing the benefits of previously elucidated mechanisms of action and already existing pharmacokinetic profiles. One class of drugs a wealth of clinical data and extensively studied safety profiles is the statins, a class of antilipidemic drugs widely prescribed for hypercholesterolemia. In addition to these widely utilized lipid-lowering effects, increasing data from cellular, pre-clinical mammalian, and clinical human studies have also demonstrated that statins are able to alleviate tissue fibrosis originating from a variety of pathological insults via lesser-studied, pleiotropic effects of these drugs. Here we review literature demonstrating evidence for direct effects of statins antagonistic to fibrosis, as well as much of the available mechanistic data underlying these effects. A more complete understanding of the anti-fibrotic effects of statins may enable a clearer picture of their anti-fibrotic potential for various clinical indications. Additionally, more lucid comprehension of the mechanisms by which statins exert anti-fibrotic effects may aid in development of novel therapeutic agents that target similar pathways but with greater specificity or efficacy.

Effectiveness and mechanism of metformin in animal models of pulmonary fibrosis: A preclinical systematic review and meta-analysis

Background: Pulmonary fibrosis (PF) is a lung disease with no curative drug, characterized by a progressive decrease in lung function. Metformin (MET) is a hypoglycemic agent with the advantages of high safety and low cost and has been used in several in vivo trials to treat fibrotic diseases.

Objective: This study aimed to explore the efficacy and safety of MET in treating PF and elaborate on its mechanism.

Methods: Eight databases were searched for in vivo animal trials of MET for PF from the time of database creation until 1 March 2022. The risk of bias quality assessment of the included studies was conducted using SYRCLE’s risk of bias assessment. Pulmonary inflammation and fibrosis scores were the primary outcomes of this study. Hydroxyproline (HYP), type I collagen (collagen I), α-smooth muscle actin (α-SMA), transforming growth factor-β (TGF-β), Smad, AMP-activated protein kinase (AMPK), and extracellular signal–regulated kinase (ERK) protein expression in lung tissues and animal mortality were secondary outcomes. Effect magnitudes were combined and calculated using Revman 5.3 and Stata 16.0 to assess the efficacy and safety of MET in animal models of PF. Inter-study heterogeneity was examined using the I² or Q test, and publication bias was assessed using funnel plots and Egger’s test.

Results: A total of 19 studies involving 368 animals were included, with a mean risk of bias of 5.9. The meta-analysis showed that MET significantly suppressed the level of inflammation and degree of PF in the lung tissue of the PF animal model. MET also reduced the content of HYP, collagen I, α-SMA, and TGF-β and phosphorylation levels of Smad2, Smad3, p-smad2/3/smad2/3, ERK1/2, and p-ERK1/2/ERK1/2 in lung tissues. MET also elevated AMPK/p-AMPK levels in lung tissues and significantly reduced animal mortality.

Conclusion: The results of this study suggest that MET has a protective effect on lung tissues in PF animal models and may be a potential therapeutic candidate for PF treatment.

Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=327285, identifier CRD42022327285.

A Single-Cell Network-Based Drug Repositioning Strategy for Post-COVID-19 Pulmonary Fibrosis

Post-COVID-19 pulmonary fibrosis (PCPF) is a long-term complication that appears in some COVID-19 survivors. However, there are currently limited options for treating PCPF patients. To address this problem, we investigated COVID-19 patients’ transcriptome at single-cell resolution and combined biological network analyses to repurpose the drugs treating PCPF. We revealed a novel gene signature of PCPF. The signature is functionally associated with the viral infection and lung fibrosis. Further, the signature has good performance in diagnosing and assessing pulmonary fibrosis. Next, we applied a network-based drug repurposing method to explore novel treatments for PCPF. By quantifying the proximity between the drug targets and the signature in the interactome, we identified several potential candidates and provided a drug list ranked by their proximity. Taken together, we revealed a novel gene expression signature as a theragnostic biomarker for PCPF by integrating different computational approaches. Moreover, we showed that network-based proximity could be used as a framework to repurpose drugs for PCPF.

Evaluation for clinical benefit of metformin in patients with idiopathic pulmonary fibrosis and type 2 diabetes mellitus: a national claims-based cohort analysis

Background

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease with high morbidity and limited treatment options. Type 2 diabetes mellitus (T2DM) is a common comorbid illness among patients with IPF and is often treated with metformin, the first-line agent in the management of T2DM. There is growing evidence demonstrating metformin’s anti-fibrotic properties; however, there is little real-world clinical data regarding its potential effectiveness in IPF. This study aims to evaluate the clinical benefit of metformin in patients with IPF and T2DM.

Methods

This nationwide cohort study used de-identified administrative claims data from OptumLabs® Data Warehouse to identify 3599 adults with IPF and concomitant T2DM between January 1, 2014 and June 30, 2019. Two cohorts were created: a cohort treated with metformin (n = 1377) and a cohort not treated with metformin (n = 2222). A final 1:1 propensity score-matched cohort compared 1100 patients with IPF and T2DM receiving metformin to those with both diagnoses but not receiving metformin; matching accounted for age, sex, race/ethnicity, residence region, year, medications, oxygen use, smoking status, healthcare use, and comorbidities. Outcomes were all-cause mortality (primary) and hospitalizations (secondary).

Results

Among 2200 patients with IPF and T2DM included in this matched analysis, metformin therapy was associated with a reduction in all-cause mortality (hazard ratio [HR], 0.46; 95% confidence interval [CI], 0.36–0.58; p < 0.001) and hospitalizations (HR, 0.82; 95% CI, 0.72–0.93; p = 0.003) compared to patients not receiving metformin.

Conclusions

Among patients with IPF and T2DM, metformin therapy may be associated with improved clinical outcomes. However, further investigation with randomized clinical trials is necessary prior to metformin’s broad implementation in the clinical management of IPF.

Extracellular Lipids in the Lung and Their Role in Pulmonary Fibrosis

Lipids are major actors and regulators of physiological processes within the lung. Initial research has described their critical role in tissue homeostasis and in orchestrating cellular communication to allow respiration. Over the past decades, a growing body of research has also emphasized how lipids and their metabolism may be altered, contributing to the development and progression of chronic lung diseases such as pulmonary fibrosis. In this review, we first describe the current working model of the mechanisms of lung fibrogenesis before introducing lipids and their cellular metabolism. We then summarize the evidence of altered lipid homeostasis during pulmonary fibrosis, focusing on their extracellular forms. Finally, we highlight how lipid targeting may open avenues to develop therapeutic options for patients with lung fibrosis.

Progress of Statin Therapy in the Treatment of Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a type of interstitial lung disease (ILD) characterized by the proliferation of fibroblasts and aberrant accumulation of extracellular matrix. These changes are accompanied by structural destruction of the lung tissue and the progressive decline of pulmonary function. In the past few decades, researchers have investigated the pathogenesis of IPF and sought a therapeutic approach for its treatment. Some studies have shown that the occurrence of IPF is related to pulmonary inflammatory injury; however, its specific etiology and pathogenesis remain unknown, and no effective treatment, with the exception of lung transplantation, has been identified yet. Several basic science and clinical studies in recent years have shown that statins, the traditional lipid-lowering drugs, exert significant antifibrotic effects, which can delay the progression of IPF and impairment of pulmonary function. This article is aimed at summarizing the current understanding of the pathogenesis of IPF, the progress of research on the use of statins in IPF models and clinical trials, and its main molecular targets.

The Effect of Cardiovascular Medications on Disease-Related Outcomes in Idiopathic Pulmonary Fibrosis: A Systematic Review and Meta-Analysis

Background: Multiple studies have revealed that idiopathic pulmonary fibrosis (IPF) patients are more at risk for cardiovascular diseases and that many IPF patients receive cardiovascular medications like statins, angiotensin-converting enzyme inhibitor (ACEI), angiotensin receptor blocker (ARB), and anticoagulants. Existing studies have reported divergent findings on the link between cardiovascular medications and fibrotic disease processes. The aim of this study is to synthesize the evidence on the efficacy of cardiovascular medications in IPF. Methods: We searched studies reporting the effect of cardiovascular medications on IPF in the PubMed, Embase, Web of Science, Cochrane Library, and two Chinese databases (China National Knowledge Infrastructure database and China Wanfang database). We calculated survival data, forced vital capacity (FVC) decline, and IPF-related mortality to assess the efficacy of cardiovascular medications in IPF. We also estimated statistical heterogeneity by using I² and Cochran Q tests, and publication bias was evaluated by risk of bias tools ROBINS-I. Results: A total of 12 studies were included in the analysis. The included studies had moderate-to-serious risk of bias. Statin use was associated with a reduction in mortality (hazard ratio (HR), 0.89; 95% CI 0.83-0.97). Meta-analysis did not demonstrate any significant relationship between statin use and the FVC decline (HR, 0.86; 95% CI 0.73-1.02), ACEI/ARB use, and survival data (HR, 0.92; 95% CI 0.73-1.15) as well as anticoagulant use and survival data (HR, 1.16; 95% CI 0.62-2.19). Conclusion: Our study suggested that there is a consistent relationship between statin therapy and survival data in IPF population. However, there is currently insufficient evidence to conclude the effect of ACEI, ARB, and anticoagulant therapy on IPF population especially to the disease-related outcomes in IPF.