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Aging, COPD, and other risk factors do not explain the increased prevalence of pulmonary Mycobacterium avium complex

Mohammed Al-Houqani1, Frances Jamieson2, Mauli Mehta3

  • 1Faculty of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates.

Chest
|July 5, 2011
PubMed
Abstract

Insights

Increases in pulmonary Mycobacterium avium complex (pMAC) disease are partly explained by aging and COPD, but remain multifactorial. Environmental or pathogen factors may also contribute to rising pMAC cases.

Area of Science:

  • Pulmonary Medicine
  • Infectious Diseases
  • Epidemiology

Background:

  • Pulmonary Mycobacterium avium complex (pMAC) isolation and disease rates have increased, with the cause remaining unexplained.
  • This study investigates potential drivers of rising pMAC prevalence in Ontario, Canada.

Purpose of the Study:

  • To explore population-level risk factors contributing to the increase in pMAC isolation and disease.
  • To determine the impact of aging, HIV, solid organ transplant, COPD, and TNF-α inhibition on pMAC disease trends.

Main Methods:

  • Analyzed patient data for pMAC disease between 2003 and 2008, including age and sex.
  • Estimated the contribution of demographic and clinical factors to observed increases in pMAC disease.

Main Results:

  • pMAC isolation and disease prevalence increased from 8.44 to 12.62 and 4.35 to 6.81 per 100,000, respectively.
  • Population aging could account for 70 additional cases, while increased COPD prevalence explained 11 cases.
  • HIV, solid organ transplant, and TNF-α inhibition combined explained no more than 73 additional cases.

Conclusions:

  • Population aging is a significant risk factor, but only partially explains the rise in pMAC disease.
  • The increase in pMAC disease is likely multifactorial, potentially involving environmental or pathogen factors.
  • Further research is needed to identify all contributing factors to the pMAC disease increase.

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