Mortality factors in idiopathic inflammatory myopathy: focusing on malignancy and interstitial lung disease

The prevalence, clinical features, predictive factors and investigations to screen for cancer in patients with inflammatory myositis. A case series from two tertiary care centers in Riyadh, Saudi Arabia

Objectives:

To describes the epidemiology of cancer in patients with idiopathic inflammatory myopathies (IIM) treated at 2 tertiary centers in Riyadh, Saudi Arabia.

Methods:

This was a retrospective multi-center study evaluating the prevalence and the type of malignancy in an IIM population in King Saud University Medical City and King Abdulaziz Medical City between August 2017 to August 2018.

Results:

In total, 60 patients were included. Four had neoplasms (6.7%), 2 men had lymphoma, a woman had breast cancer and a second, ovarian cancer. Two patients died due to cancer or its complications. Older age (age >40 years), dysphagia, necrotic rash, absence of interstitial lung disease, high erythrocyte sedimentation rate and a negative anti Jo-1 antibody were potentially predictive risk factors for neoplasm. All patients diagnosed with cancer-associated myositis were investigated with routine and invasive modalities. Three of the 4 patients had abnormal findings in both modalities. One patient, the routine investigations were unremarkable, but a computed tomography of the pelvis revealed an ovarian mass that was subsequently diagnosed as malignant.

Conclusion:

An individualized approach might be more appropriate for high risk patients. Larger prospective studies are required to confirm the findings of the current study.

Analysis of risk factors of interstitial lung disease and mortality rates in Chinese patients with idiopathic inflammatory myopathy

Aim

To investigate the risk factors for interstitial lung disease (ILD) and prognosis in patients with idiopathic inflammatory myopathy (IIM).

Methods

A retrospective longitudinal study was performed in patients diagnosed with IIM between January 2012 and December 2018.

Results

The study cohort included 91 men and 195 women who were classified as having dermatomyositis (DM, n = 183), polymyositis (PM, n = 77), or clinical amyopathic DM (CADM, n = 26). ILD was identified in 46.5% (n = 133) of patients with IIM. The independent risk factors for ILD were age at disease onset, presence of anti‐Ro‐52 antibody, Gottron's papules, elevated serum immunoglobulin M levels and hypoalbuminemia. Older age at disease onset, ILD, malignancy, and increased serum aspartate aminotransferase and neutrophil‐to‐lymphocyte ratio (NLR) were identified as the independent predictors for mortality, whereas elevated serum albumin level was associated with a better prognosis. A total of 73 deaths (25.5%) occurred after a median follow‐up time of 33 months. Infection (49.3%) was the leading cause of death. In the overall cohort, the 1‐year, 5‐year and cumulative survival rates were 83.2%, 74.2% and 69.4%, respectively. The receiver operating characteristic curve indicated that the optimal cut‐off value of NLR for predicting death in IIM was 6.11.

Conclusion

IIM patients have a poor prognosis with substantial mortality, especially in patients who have older age at onset, ILD, malignancy and higher NLR. Close monitoring and aggressive therapies are required in patients having poor predictive factors.

The ILD-GAP risk prediction model performs poorly in myositis-associated interstitial lung disease

PURPOSE

Myositis-associated interstitial lung disease (MA-ILD) is associated with increased mortality, but no prognostic model exists in this population. The ILD-GAP index was developed to predict mortality risk across all subtypes of chronic ILD. The purpose of this study was to validate the ILD-GAP risk prediction model in patients with MA-ILD.

PROCEDURES

We completed a retrospective cross-sectional study of patients enrolled in the Johns Hopkins Myositis Center database between 2006 and 2017. Cumulative mortality rates were estimated using the Kaplan-Meier test. Model calibration was determined by using standardized mortality ratios of observed versus expected deaths.

MAIN FINDINGS

179 participants with MA-ILD were included. The mean baseline percent predicted forced vital capacity was 65.2 ± 20.6%, forced expiratory volume in the first second 65.4 ± 20.4%, and carbon monoxide diffusing capacity 61.6 ± 20.0%. Thirty-two participants died (17.9%). The ILD-GAP model had poor discriminative performance and calibration.

CONCLUSIONS

The ILD-GAP risk prediction model is a poor predictor of mortality among individuals with MA-ILD. The identification of a better predictive model for MA-ILD is needed to help guide care in this patient population.

Hospitalization mortality and associated risk factors in patients with polymyositis and dermatomyositis: A retrospective case-control study

BACKGROUND

Polymyositis and dermatomyositis (PM/DM) are systemic autoimmune diseases with multiple organ involvements that manifest as muscular and cutaneous disorders, interstitial lung disease (ILD) and malignancies. However, information concerning the outcomes and associated factors for PM/DM patients who are hospitalized is limited.

METHODS

We retrospectively reviewed the medical charts of PM/DM patients admitted to a Chinese tertiary referral hospital (Peking Union Medical College Hospital, PUMCH) from 2008 to 2014. The deceased group included 63 patients who had "deceased discharge" status or were confirmed to have died within two weeks of hospital discharge. The demographic data, clinical manifestations, and direct causes of death were analyzed retrospectively. Medical records for 126 age- and sex-matched PM/DM patients were selected as controls from 982 inpatients successively admitted to the same center during the same period. In addition to the comparison of clinical manifestations between the two groups, binary logistic regression was conducted to explore the risk factors related to PM/DM mortality.

RESULTS

Over the past 6 years at PUMCH, the in-hospital mortality rate of PM/DM patients was 4.58%. The male gender and the elder patients had a high risk of death (P = 0.031 and P = 0.001 respectively). The three most frequent causes of death for PM/DM patients were pulmonary infection (35%), ILD exacerbation (21%) or both conditions (25%). Pulmonary infection (P<0.001, OR = 5.63, 95% CI, 2.37-13.36), pneumomediastinum (P = 0.041, OR = 11.02, 95%CI, 1.10-110.54), Gottron's papules (P = 0.010, OR = 3.24, 95%CI, 1.32-7.97), and elevated erythrocyte sedimentation rate (ESR) (P = 0.005, OR = 9.9, 95%CI 2.0-49.0) were independent risk factors for in-hospital mortality of PM/DM patients.

CONCLUSION

PM/DM patients continue to display high in-hospital mortality. Pulmonary infection is the strongest predictor of poor prognosis in PM/DM patients, followed by pneumomediastinum, Gottron's papules, and elevated ESR.

Assessment of Mortality in Autoimmune Myositis With and Without Associated Interstitial Lung Disease

PURPOSE

Among patients with autoimmune myositis, associated interstitial lung disease (MA-ILD) is a known contributor of excess morbidity and mortality. Recent data on survival in idiopathic inflammatory myopathies originate primarily in Asia and Europe and vary widely. We sought to examine mortality in a large U.S. myositis cohort focusing in particular on the impact of associated ILD.

METHODS

A cross-sectional analysis of participants from the Johns Hopkins Myositis Center with autoimmune myositis (polymyositis [PM], dermatomyositis [DM], or clinically amyopathic dermatomyositis [CADM]) was conducted. The primary outcome assessed was all-cause mortality. Cumulative mortality rates were estimated using the Kaplan-Meier test; the Cox proportional hazards model was used to compare group differences in survival.

RESULTS

Eight hundred and thirty-one participants were included with a median follow-up time of 4.5 years. Four hundred thirty-eight (53 %) had PM, 362 (43 %) had DM, and 31 (4 %) had CADM. Ninety-four (11 %) participants had clinically evident ILD. Overall, 51 participants died (6 %). In those without ILD, the survival rates at 1, 5, and 10 years were 99, 95, and 90 %, respectively. In those with ILD, the survival rates at 1, 5, and 10 years were 97, 91, and 81 %, respectively. The risk of death was statistically significantly higher among participants with ILD compared to those without ILD (HR 2.13. 95 % CI 1.06-4.25; p = 0.03).

CONCLUSIONS

We analyzed one of the largest known cohorts of patients with autoimmune myositis and found significantly higher mortality rates among those with clinically evident ILD compared to those without clinically evident ILD. Our results suggest that ILD remains an important and significant source of mortality in patients with inflammatory myopathies and as such should be screened for and treated aggressively.

Investigation into the cause of mortality in 49 cases of idiopathic inflammatory myopathy: A single center study

Idiopathic inflammatory myopathy (IIM) is an autoimmune disease characterized by chronic muscle weakness and myositis with unknown etiology. IIM may affect the function of multiple organs and has a poor prognosis. In the present study, the causes of mortality in patients with IIM admitted to the Xiangya Hospital during the last 14 years were investigated. The investigation included an analysis of frequent causes of IIM, and of infections and associated complications. A cohort study was conducted on 676 patients with IIM that were admitted to Xiangya Hospital from January, 2001 to January, 2015. There were 49 patient mortalities (7.2% of the total cases), of which 34 mortalities were infection-associated and 15 were not infection-associated. The proportion of infection-associated IIM mortalities had increased since 2001. Of the 34 infection-associated mortalities, 31 cases (63.3%) were of fungal and bacterial infections, most frequently infecting the lungs and the blood. Klebsiella pneumoniae and Acinetobacter baumannii were the most commonly isolated pathogens, and co-infection with the two pathogens was observed in the majority of cases. In the IIM mortalities not associated with infection, there were 2 acute myocardial infarction cases, 2 acute interstitial lung disease cases, 4 malignancies and 1 case of each of the following: Arrhythmia, pneumothorax, ventilator weakness, pulmonary artery hypertension, gastrointestinal bleeding, liver failure and renal failure. Three mortalities were secondary to viral hepatitis in the present study. Pathogenic infection was the most frequent cause of mortality in patients with IIM. The remaining causes of mortality included secondary to heart failure, lung dysfunction and malignancy. Following the ubiquitous application of glucocorticoids and immunosuppressants, the proportion of infection-associated mortalities increased in patients with IIM. Thus, in addition to focusing on the primary disease, infection should receive increased attention during clinical practice.

Early illness features associated with mortality in the juvenile idiopathic inflammatory myopathies

OBJECTIVE

Because juvenile idiopathic inflammatory myopathies (IIMs) are potentially life-threatening systemic autoimmune diseases, we examined risk factors for juvenile IIM mortality.

METHODS

Mortality status was available for 405 patients (329 with juvenile dermatomyositis [DM], 30 with juvenile polymyositis [PM], and 46 with juvenile connective tissue disease-associated myositis [CTM]) enrolled in nationwide protocols. Standardized mortality ratios (SMRs) were calculated using US population statistics. Cox regression analysis was used to assess univariable associations with mortality, and random survival forest (RSF) classification and Cox regression analysis were used for multivariable associations.

RESULTS

Of 17 deaths (4.2% overall mortality), 8 (2.4%) were in juvenile DM patients. Death was related to the pulmonary system (primarily interstitial lung disease [ILD]) in 7 patients, gastrointestinal system in 3, and multisystem in 3, and of unknown etiology in 4 patients. The SMR for juvenile IIMs overall was 14.4 (95% confidence interval [95% CI] 12.2-16.5) and was 8.3 (95% CI 6.4-10.3) for juvenile DM. The top mortality risk factors in the univariable analysis included clinical subgroup (juvenile CTM, juvenile PM), antisynthetase autoantibodies, older age at diagnosis, ILD, and Raynaud's phenomenon at diagnosis. In multivariable analyses, clinical subgroup, illness severity at onset, age at diagnosis, weight loss, and delay to diagnosis were the most important predictors from RSF; clinical subgroup and illness severity at onset were confirmed by multivariable Cox regression analysis.

CONCLUSION

Overall mortality was higher in juvenile IIM patients, and several early illness features were identified as risk factors. Clinical subgroup, antisynthetase autoantibodies, older age at diagnosis, and ILD are also recognized as mortality risk factors in adult myositis.