Nontuberculous mycobacterial infection is associated with increased respiratory failure: a nationwide cohort study

The impact of nontuberculous mycobacterial lung disease in critically ill patients: Significance for survival and ventilator use

BACKGROUND

This study investigates the impact of nontuberculous mycobacterial lung disease (NTM-LD) on mortality and mechanical ventilation use in critically ill patients.

METHODS

We enrolled patients with NTM-LD or tuberculosis (TB) in intensive care units (ICU) and analysed their association with 30-day mortality and with mechanical ventilator-free survival (VFS) at 30 days after ICU admission.

RESULTS

A total of 5996 ICU-admitted patients were included, of which 541 (9.0 %) had TB and 173 (2.9 %) had NTM-LD. The overall 30-day mortality was 22.2 %. The patients with NTM-LD had an adjusted hazard ratio (aHR) of 1.49 (95 % CI, 1.06-2.05), and TB patients had an aHR of 2.33 (95 % CI, 1.68-3.24), compared to ICU patients with negative sputum mycobacterial culture by multivariable Cox proportional hazard (PH) regression. The aHR of age<65 years, obesity, idiopathic pulmonary fibrosis, end-stage kidney disease, active cancer and autoimmune disease and diagnosis of respiratory failure were also significantly positively associated with ICU 30-day mortality. In multivariable Cox PH regression for VFS at 30 days in patients requiring invasive mechanical ventilation, NTM-LD was negatively associated with VFS (aHR 0.71, 95 % CI: 0.56-0.92, p = 0.009), while TB showed no significant association. The diagnosis of respiratory failure itself predicted unfavourable outcome for 30-day mortality and a negative impact on VFS at 30 days.

CONCLUSIONS

NTM-LD and TB were not uncommon in ICU and both were correlated with increasing 30-day mortality in ICU patients. NTM-LD was associated with a poorer outcome in terms of VFS at 30 days.

Incremental mortality associated with nontuberculous mycobacterial lung disease among US Medicare beneficiaries with chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a common comorbidity in patients with nontuberculous mycobacterial lung disease (NTMLD). Both conditions are associated with increased morbidity and mortality, but data are lacking on the additional burden associated with NTMLD among patients with COPD. Thus, the goal of this study was to assess the incremental mortality risk associated with NTMLD among older adults with COPD.

METHODS

A retrospective cohort study was conducted using the US Medicare claims database (2010-2017). Patients with preexisting COPD and NTMLD (cases) were matched 1:3 by age and sex with patients with COPD without NTMLD (control patients). Patients were followed up until death or data cutoff (December 31, 2017). Incremental risk of mortality was evaluated by comparing the proportions of death, annualized mortality rate, and mortality hazard rate between cases and control patients using both univariate and multivariate analyses adjusting for age, sex, comorbidities, and COPD severity.

RESULTS

A total of 4,926 cases were matched with 14,778 control patients. In univariate analyses, a higher proportion of cases (vs. control patients) died (41.5% vs. 26.7%; P < 0.0001), unadjusted annual mortality rates were higher among cases (158.5 vs. 86.0 deaths/1000 person-years; P < 0.0001), and time to death was shorter for cases. This increased mortality risk was also reflected in subsequent multivariate analyses. Patients with COPD and NTMLD were more likely to die (odds ratio [95% CI], 1.39 [1.27-1.51]), had higher mortality rates (rate ratio [95% CI], 1.36 [1.28-1.45]), and had higher hazard of death (hazard ratio [95% CI], 1.37 [1.28-1.46]) than control patients.

CONCLUSIONS

The substantial incremental mortality burden associated with NTMLD in patients with COPD highlights the importance of developing interventions targeting this high-risk group and may indicate an unmet need for timely and appropriate management of NTMLD.

The Impact of Nontuberculous Mycobacteria Species on Mortality in Patients With Nontuberculous Mycobacterial Lung Disease

Patients with nontuberculous mycobacterial lung disease (NTM-LD) have increased mortality. The impact of NTM species on the risk of mortality remains unclear, especially that of death by non-cancer causes. We conducted a retrospective cohort study from 2006 to 2018 in a tertiary-care hospital in Taiwan. We enrolled patients who fulfilled the microbiological diagnostic criteria of NTM-LD. The mortality causes within 8 years after diagnosis were identified, and the Cox proportional hazard regression was performed for risk factors of mortality. A total of 1,652 subjects with NTM-LD were included. Among them, 723 (43.8%) were infected by Mycobacterium avium complex (MAC), 408 (24.7%) by M. abscessus complex (MABC), 120 (7.3%) by Mycobacterium kansasii (MK), 304 (18.4%) by other rapid-growing mycobacteria (RGM), and 97 (5.9%) by other slow-growing mycobacteria (SGM) groups. The 8-year all-cause mortality was 45.2% for all and the highest in the MK-LD group (59.2%), followed by the MABC-LD and MAC-LD groups. The adjusted hazard ratios were 2.20 (95% confidence interval: 1.40–3.46) in the MK-LD, 1.85 (1.54–2.22) in the MABC-LD, and 1.65 (1.12–2.41) in the MAC-LD groups for all-cause mortality, compared with the SGM group. Kaplan–Meier survival curves showed that all-cause mortality, non-cancer mortality, and mortality due to chronic airway diseases were significantly correlated with NTM species (log-rank p = 0.0031, < 0.001, and 0.001, respectively). High 8-year mortality rates were found in patients with NTM-LDs according to different NTM species. Notably, the difference was significant in non-cancer mortality causes, especially in chronic airway diseases.

Mycobacterial Infections Potentiated by Biologics

Biologic therapies have revolutionized the treatment of immune-mediated inflammatory diseases but are associated with an increased risk of serious and opportunistic infections, including tuberculosis and nontuberculous mycobacterial disease. Despite this increased risk, the overall risk-benefit ratio remains favorable with appropriate screening and risk assessment. Further population-based studies are needed to establish the risk of tuberculosis and nontuberculous mycobacterial disease with the new biologics. This article highlights the incidence and drug-specific risk of tuberculous and nontuberculous mycobacterial infection in the setting of biologics, screening and prevention, and treatment of latent tuberculosis in this setting.

Lower Recovery of Nontuberculous Mycobacteria from Outdoor Hawai'i Environmental Water Biofilms Compared to Indoor Samples

Nontuberculous mycobacteria (NTM) are environmental organisms that can cause opportunistic pulmonary disease with species diversity showing significant regional variation. In the United States, Hawai'i shows the highest rate of NTM pulmonary disease. The need for improved understanding of NTM reservoirs led us to identify NTM from patient respiratory specimens and compare NTM diversity between outdoor and indoor locations in Hawai'i. A total of 545 water biofilm samples were collected from 357 unique locations across Kaua'i (n = 51), O'ahu (n = 202), Maui (n = 159), and Hawai'i Island (n = 133) and divided into outdoor (n = 179) or indoor (n = 366) categories. rpoB sequence analysis was used to determine NTM species and predictive modeling applied to develop NTM risk maps based on geographic characteristics between environments. M. chimaera was frequently identified from respiratory and environmental samples followed by M. chelonae and M. abscessus; yet significantly less NTM were consistently recovered from outdoor compared to indoor biofilms, as exemplified by showerhead biofilm samples. While the frequency of M. chimaera recovery was comparable between outdoor and indoor showerhead biofilms, phylogenetic analyses demonstrate similar rpoB gene sequences between all showerhead and respiratory M. chimaera isolates, supporting outdoor and indoor environments as possible sources for pulmonary M. chimaera infections.

Incidence of nontuberculous mycobacterial disease and coinfection with tuberculosis in a tuberculosis-endemic region: A population-based retrospective cohort study

Nontuberculous mycobacteria (NTM) infection may interfere in the diagnosis and treatment of tuberculosis (TB) in TB-endemic regions. However, the population-based incidence of NTM disease and NTM-TB coinfection remains unclear.We used Taiwan's National Health Insurance Research Database to identify new diagnoses of NTM disease and TB from 2005 to 2013 and calculated the incidence rate and the proportion of NTM-TB coinfection. The patients with NTM disease or TB were determined by the use of disease codes from International Classification of Diseases, Ninth Revision, Clinical Modification, laboratory mycobacterium examination codes, and antimycobacterial therapy receipts.From 2005 to 2013, the age-adjusted incidence rate of NTM disease increased from 5.3 to 14.8 per 100,000 people per year and the age-adjusted incidence rate of NTM-TB coinfection was around 1.2 to 2.2 per 100,000 people per year. The proportion of NTM-TB coinfection among patients with confirmed TB was 2.8%. Male and older patients had a significantly higher incidence of NTM disease. The effects of urbanization and socioeconomic status (SES) on the incidences of TB and NTM disease were different. Rural living and lower SES were significantly associated with increasing the incidence of confirmed TB but not with that of NTM disease. For NTM disease, those living in the least urbanized area had significantly lower incidence rate ratio than in the highest urbanized area. The incidence of NTM-TB coinfection was higher in older patients and compared with patients aged < 45 years, the incidence rate ratio of the patients aged> 74 years was 12.5.In TB-endemic Taiwan, the incidence of NTM disease increased from 2005 to 2013. Male gender and old age were risk factors for high incidence of NTM disease. SES did not have a significant effect on the incidence of NTM disease, but rural living was associated with lower incidence of NTM disease. In TB-endemic areas, NTM-TB coinfection could disturb the diagnosis of TB and treatment, especially in elderly patients.

Risk for cardiovascular disease in patients with nontuberculous mycobacteria treated with macrolide

Background

Macrolide antibiotics are the most important pharmacological agents for the treatment of nontuberculous mycobacterial disease. We investigated the incidence of acute cardiovascular events in patients taking macrolides for nontuberculous mycobacterial disease and determined the difference in risk between clarithromycin and azithromycin.

Methods

A population-based retrospective cohort study was conducted in South Korea using the Health Insurance Review and Assessment Service database. Patients ≥40 years treated with macrolide for nontuberculous mycobacteria (NTM) between 2011 and 2015 were examined. The primary outcome was hospitalization or emergency department visit for cardiovascular disease along with acute myocardial infarction, cerebrovascular disease, and cardiac arrhythmia. The standardized incidence ratio (SIR) for cardiovascular disease was calculated by comparing the patients with the general population in the year 2013. Cox proportional hazard model was used to compare the risk between clarithromycin and azithromycin.

Results

In total, 16,525 patients with nontuberculous mycobacterial disease treated with macrolide were included; 13,870 received clarithromycin and 2,655 received azithromycin. The cardiovascular incidence was significantly higher in patients with nontuberculous mycobacterial disease than in the age- and sex-stratified general population [SIR, 1.44; 95% confidence interval (CI), 1.27-1.61]. The risk was not significantly different between patients treated with clarithromycin and azithromycin (adjusted hazard ratio, 0.90; 95% CI, 0.65-1.24).

Conclusions

The incidence of cardiovascular disease was significantly higher in patients treated with macrolide for nontuberculous mycobacterial disease than in the general population. This risk was not different between patients treated with clarithromycin and azithromycin.

Risk Factors and Outcomes of Nontuberculous Mycobacterial Disease among Rheumatoid Arthritis Patients: A Case-Control study in a TB Endemic Area

Increasing evidence indicates that the risk of nontuberculous mycobacteria (NTM) disease is elevated in patients with rheumatoid arthritis (RA). However, the risk factors and outcomes for NTM disease among RA patients remain unclear. We conducted a case-control study and estimated odds ratios (ORs) for RA patients with NTM disease according to comorbidities and anti-rheumatic medications by using conditional logistic regression. Prior tuberculosis history (adjusted OR (aOR) =5.58, p < 0.001), hypertension (aOR = 2.55, p = 0.013), diabetes mellitus (aOR = 3.31, p = 0.005), interstitial lung disease (aOR = 8.22, p < 0.001), chronic obstructive pulmonary disease (aOR = 8.59, p < 0.001) and exposure to oral corticosteroids in a dose-dependent manner (5- < 10 mg/day aOR = 2.51, Ptrend = 0.007) were associated with a significantly increased risk of NTM disease in RA patients. The predominant species causing NTM disease in RA patients was Mycobacterium intracellulare (46.0%). Most NTM isolates were resistant to the majority of the antibiotics that are currently available, which maybe caused treatment failure; hospitalization and mortality are increased. To prevent and treat NTM disease efficiently, we suggested that it is important to monitor the development of NTM disease in RA patients receiving therapy with corticosteroids, particularly in those with predisposing factors.

Risk for Mycobacterial Disease among Patients with Rheumatoid Arthritis, Taiwan, 2001-2011

Increasing evidence indicates that the risk of acquiring tuberculosis (TB) and nontuberculous mycobacterial disease is elevated among patients with rheumatoid arthritis (RA). To determine the epidemiology of mycobacterial diseases among RA patients in Asia, we conducted a retrospective cohort study. We used a nationwide database to investigate the association of RA with mycobacterial diseases. The risk for development of TB or nontuberculous mycobacterial disease was 2.28-fold and 6.24-fold higher among RA patients than among the general population, respectively. Among RA patients, risk for development of mycobacterial disease was higher among those who were older, male, or both. Furthermore, among RA patients with mycobacterial infections, the risk for death was increased. Therefore, RA patients, especially those with other risk factors, should be closely monitored for development of mycobacterial disease.

Clinical findings in relation to mortality in non-tuberculous mycobacterial infections: patients with Mycobacterium avium complex have better survival than patients with other mycobacteria

We compared the clinical findings and survival in patients with Mycobacterium avium complex (MAC) and other non-tuberculous mycobacteria (NTM). A total of 167 adult non-human immunodeficiency virus (HIV) patients with at least one positive culture for NTM were included. Medical records were reviewed. The patients were categorised according to the 2007 American Thoracic Society (ATS) criteria. MAC comprised 59 % of all NTM findings. MAC patients were more often female (70 % vs. 34 %, p < 0.001) and had less fatal underlying diseases (23 % vs. 47 %, p = 0.001) as compared to other NTM patients. Symptoms compatible with NTM infection had lasted for less than a year in 34 % of MAC patients but in 54 % of other NTM patients (p = 0.037). Pulmonary MAC patients had a significantly lower risk of death compared to pulmonary other NTM (hazard ratio [HR] 0.50, 95 % confidence interval [CI] 0.33–0.77, p = 0.002) or subgroup of other slowly growing NTM (HR 0.55, 95 % CI 0.31–0.99, p = 0.048) or as rapidly growing NTM (HR 0.47, 95 % CI 0.25–0.87, p = 0.02). The median survival time was 13.0 years (95 % CI 5.9–20.1) for pulmonary MAC but 4.6 years (95 % CI 3.4–5.9) for pulmonary other NTM. Serious underlying diseases (HR 3.21, 95 % CI 2.05–5.01, p < 0.001) and age (HR 1.07, 95 % CI 1.04–1.09, p < 0.001) were the significant predictors of mortality and female sex was a predictor of survival (HR 0.38, 95 % CI 0.24–0.59, p < 0.001) in the multivariate analysis. Pulmonary MAC patients had better prognosis than pulmonary other NTM patients. The symptom onset suggests a fairly rapid disease course.

Rheumatoid arthritis increases the risk of nontuberculosis mycobacterial disease and active pulmonary tuberculosis

Background

Few studies have examined the association of rheumatoid arthritis (RA) with nontuberculosis mycobacterium (NTM) disease and pulmonary tuberculosis (PTB).

Methods

We identified 29 131 patients with RA from the catastrophic illness registry who were diagnosed from 1998–2008; 116 524 patients without RA from inpatient data files were randomly frequency matched according to sex, age, and index year and used as a comparison group. Both groups were followed-up until the end of 2010 to measure the incidence of NTM disease and active PTB. We analyzed the risk of NTM disease and active PTB using the Cox proportional hazards regression models, controlling for sex, age, and Charlson comorbidity index (CCI).

Results

The incidence of NTM disease was 4.22 times greater in the RA group than in the non-RA group (1.91 vs 0.45 per 10,000 person-years). The incidence of PTB was 2.99 times greater in the RA group than in the non-RA group (25.3 vs 8.46 per 10,000 person-years). After adjusting for age, sex, and CCI, the adjusted hazard ratios (HRs) of NTM disease and active PTB for the RA group were 4.17 (95% CI = 2.61–6.65) and 2.87 (95% CI = 2.55–3.23), respectively, compared with the non-RA group. In the first 2 years of follow-up, the RA group yielded corresponding adjusted HRs of 4.98 and 3.39 compared with the non-RA group. The follow-up time-specific RA group to the non-RA group HR of both the NTM disease and active PTB varied.

Conclusion

This study can serve as a reference for clinical physicians to increase awareness regarding the detection of NTM disease and active PTB in RA patients among the any stage of the clinical course even without CCI.