**1. Introduction**

Regulation of the lung inflammatory response is critical to the successful resolution of pneumonia. Exposure to air pollutants has been linked to negative lung health outcomes, and both male

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

and female sex hormones have been shown to control the lung immune response [1, 2]. This chapter combines evidence of three areas: pneumonia infection, air pollution, and hormonal control of sex-specific immune responses. We will discuss common pathogens responsible for pneumonia and associations with environmental exposures, and lessons learned from animal models of infection and exposure to various air pollutants. Together, this information could help better explain the differences observed in susceptibility to pneumonia between men and women, and help in the development of better treatment options for male and female patients.

an important role in the predisposition of some respiratory infections [11, 12]. Although some studies in animals have shown that females are more resistant than males to some bacterial infections [13, 14], others have shown that these patterns are reversed if animals are pre-exposed to environmental pollutants, such as ozone [15–20]. Incidentally, some clinical studies have reported that men are more susceptible to developing CAP and receive more intensive care than women, and show increased risk to die from pneumonia [21]. Moreover, exposure to air pollution has been associated with an increased risk for respiratory disorders due to its negative effects on lung function and immunity [22]. In this regard, long-term exposures to air pollutants, such as ozone, nitric oxide, and particulate matter in older adults have been linked with increased hospitalization rates for CAP [11, 21, 23, 24]. In addition, exposure to diverse environmental agents has been linked to negative lung health outcomes in children and adults (**Table 1**). The mechanisms

Understanding the Intersection of Environmental Pollution, Pneumonia, and Inflammation: Does...

exposure

fuel use

smoke

Higher in females Air pollution Outpatient visits

, NO<sup>2</sup> )

(PM2.5, SO<sup>2</sup>

sulfur oxides

N/A Tobacco smoke Sinusitis, middle

N/A Particulate matter (PM10)

N/A House biomass

Higher in females Air pollution

N/A UV radiation,

**Table 1.** Effects of the environment on respiratory tract health in children and adults and observed sex differences.

Health outcome Sex differences

http://dx.doi.org/10.5772/intechopen.69627

5

Higher in males

Higher in women

Higher in males

Flight attendants

(smokers) Higher in females (never smokers)

N/A

N/A

Pneumonia Higher in males

Chronic laryngitis

Various communicable respiratory disease

Communityacquired pneumonia (elderly)

for respiratory disease

Invasive pneumococcal disease

ear infections

associated with these clinical outcomes will be discussed in the following sections.

Health outcome Sex differences Environmental

Pneumonia Higher in males Secondhand

**Children Adults**

Pneumonia (incidence and severity)

Bronchitis

for respiratory disease

Mortality

Pneumonia Chronic bronchitis

Pneumonia N/A

Severe pneumonia

Air pollution Pneumonia,

Air pollution Outpatient visits

Solid fuel Pneummonia,

Environmental exposure

Secondhand smoke

Household air quality

Environmental tobacco smoking

Indoor air pollution (solid fuel cooking, keeping large animals)

SO<sup>2</sup> , total suspended particles
