Nationwide Increasing Incidence of Nontuberculous Mycobacterial Diseases Among Adults in Denmark: Eighteen Years of Follow-Up

Andreas A Pedersen; Anders Løkke; Andreas Fløe; Rikke Ibsen; Isik S Johansen; Ole Hilberg

doi:10.1016/j.chest.2024.03.023

Nationwide Increasing Incidence of Nontuberculous Mycobacterial Diseases Among Adults in Denmark: Eighteen Years of Follow-Up

Chest. 2024 Mar 16:S0012-3692(24)00393-3. doi: 10.1016/j.chest.2024.03.023. Online ahead of print.

Authors

Andreas A Pedersen¹, Anders Løkke², Andreas Fløe³, Rikke Ibsen⁴, Isik S Johansen⁵, Ole Hilberg⁶

Affiliations

¹ Department of Medicine, Lillebaelt Hospital, Vejle, Denmark; Department of Regional Health Research, University of Southern Denmark, Odense, Denmark; Mycobacterial Center for Research Southern Denmark (MyCRESD), Odense, Denmark. Electronic address: andreas.arnholdt.pedersen@rsyd.dk.
² Department of Medicine, Lillebaelt Hospital, Vejle, Denmark; Department of Regional Health Research, University of Southern Denmark, Odense, Denmark.
³ Department of Respiratory Diseases, Aarhus University Hospital, Aarhus, Denmark.
⁴ Department of Medicine, Lillebaelt Hospital, Vejle, Denmark; i2minds, Aarhus, Denmark.
⁵ Mycobacterial Center for Research Southern Denmark (MyCRESD), Odense, Denmark; Department of Infectious Diseases, Odense University Hospital, Odense, Denmark; Research Unit of Infectious Diseases, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
⁶ Department of Medicine, Lillebaelt Hospital, Vejle, Denmark; Department of Regional Health Research, University of Southern Denmark, Odense, Denmark; Mycobacterial Center for Research Southern Denmark (MyCRESD), Odense, Denmark.

PMID: 38499239
DOI: 10.1016/j.chest.2024.03.023

Abstract

Background: The epidemiology of nontuberculous mycobacteria (NTM) infections is not well described. In this study, we determine the incidence and prevalence of NTM infections and focus on social risk factors. In addition, we describe people with pulmonary and extrapulmonary NTM.

Research question: What are the incidence and prevalence of NTM, and what are the characteristics of the affected patients?

Study design and methods: This is a nationwide retrospective register-based cohort study in Denmark. Adult patients in the Danish national registers who received a diagnosis of NTM disease from 2000 to 2017 were classified as having either pulmonary or extrapulmonary NTM disease.

Results: We identified 1,146 adults with an NTM diagnosis. Of these, 661 patients had pulmonary NTM, of whom 50.4% were male, whereas 485 had extrapulmonary NTM, of whom 59.6% were male. The median age (interquartile range) was 66 (18) years and 57 (32) years, respectively. The yearly incidence rate per 100,000 increased between 2000 and 2017 for both pulmonary NTM (0.4 to 1.3) and extrapulmonary NTM (0.3 to 0.6). The annual prevalence per 100,000 increased from 0.4 to 3.5 for pulmonary NTM and from 0.3 to 1.0 for extrapulmonary NTM. The incidence rate increased with age. The incidence of pulmonary NTM was highest among those who were 70 years of age or older (19.3 per 100,000). Compared with patients with pulmonary NTM, patients with extrapulmonary NTM were more likely to be employed and had a higher educational level.

Interpretation: The prevalence of NTM disease in Denmark increased between 2000 and 2017. Patients with pulmonary NTM and patients with extrapulmonary NTM represent two distinct groups that differ in age, sex, education, and employment status. Increased suspicion of pulmonary NTM disease is warranted in the elderly after exclusion of more common lung infections.

Keywords: epidemiology; nontuberculous mycobacterial disease; nontuberculous mycobacterial extrapulmonary disease; nontuberculous mycobacterial pulmonary disease.