Tuberculosis mortality is influenced by the density of the living trees

reference

rj Blount, L. Pascopella, P. Barry et al. The crown roof of urban living trees is associated with a reduced mortality of mortality during tuberculosis treatment in California. sci Total Environ . 2020; 711: 134580.

Study goal

Determination of the connection between urban tree coverage and mortality by outpatient tuberculosis (TB) infection.

participant

All patients with diagnosed TB infection in the state of California between 2000 to 2012 (n = 33,962; average age 46.9 years; 59.4 % male), according to the Californian TB register.

draft

The researchers pursued the morbidity and mortality status of the participants and compared it with the amount of tree population, which surrounds their residential address (or in the case of homelessness the accommodation or crossing of the road, which is closest to the place where they spend most of their time), as investigated by a nationwide satellite-based vegetation detection database. The researchers used 4 different buffer zones with different radii (50 m, 100 m, 200 m and 300 m), whereby the tree cover was shown as a percentage of the entire land area and divided into quintile for analysis.

The data was checked for demographic, socio-economic and clinical covariates: age, gender, breed, ethnicity, immigration within one year, household income, employment status, drug abuse, homelessness and simultaneous HIV infection.

target parameter

The researchers rated 2 results:

• mortality rate, divided into 3 categories: TB-related, cardiopulmonary and others)
• Acid-Fast Bacilli (AFB) Sputum smear: The usual method to determine the presence of pathogenic TB bacteria

important knowledge

For each of the 4 buffer radii (50 m–300 m), there was a reverse relationship between the percentage of tree covering and the overall mortality, the TB-related and cardiopulmonary mortality. After adjustments to all covariates, the comparison of the highest with the lowest tree cover quintile showed significant reductions in the overall mortality risk as follows:

• 50 m buffer: 22 % reduced risk (HR 0.78, 95 % KI 0.68–0.90, p = 0.0003)
• 100 m buffer: 21 % reduced risk (HR 0.79, 95 % KI 0.68–0.91, p = 0.002)
• 200 m buffer: 13 % reduced risk (HR 0.87, 95 % KI 0.75–1.00, p = 0.02)
• 300 m buffer: 11 % reduced risk (HR 0.89, 95 % KI 0.77–1.04, p = 0.03)

In addition, the researchers for each of the 4 buffer radii measure an opposite relationship between the percentage tree covering and the positivity of the AFB sputum smear. After adjustments to all covariates, the comparison of the highest with the lowest tree cover quintile showed significant reductions in the positivity of the AFB sputum smear as follows:

• 50 m buffer: 7 % reduced opportunities (OR 0.93, 95 % KI 0.86–1.01, p = 0.02)
• 100 m buffer: 11 % reduced opportunities (OR 0.89, 95 % KI 0.82–0.96, p = 0.001)
• 200 m buffer: 14 % reduced opportunities (OR 0.86, 95 % KI 0.79–0.93, p = 0.0002)
• 300 m buffer: 12 % reduced risk (OR 0.88, 95 % KI 0.81–0.96, p = 0.002)

The positivity of the AFB sputum smear was directly connected to the patient mortality, as is typical for a TB infection.

Comment

This current study is the first to examine the effects of Green areas on a certain respiratory infectious disease (TB). The readers of the literature "green space and health" is aware that the proximity to various forms of "nature" has a positive effect on the state of health and the prevalence of diseases. ^{1 Large -scale surveys to public health have shown the opposite connection between life near green spaces and the mortality rate. shown that the mortality rates decrease due to respiratory diseases when people live surrounded by a denser green area.}

This is a contemporary knowledge to possibly tackle the current global Covid-19 pandemic, which has also shown a connection between air pollution concentration and respiratory morbidity and mortality.

There are many mechanisms that are responsible for the health -promoting ability of nature that have been discussed in this and other magazines. ^{5.6 One of the most relevant factors in connection with mortality in respiratory diseases is the ability of vegetation to reduce air pollution and improve air quality. This happens via 2 processes:}

1. Das filing of fine dust (pm), such as soot, ash and combustion products, on overgrown surfaces, effort you out of the air; and
2. The absorption of toxic gases (e.g. no _{x ö 3 ) in leaves as part of the respiratory function of plants, filter you from the air.}

The extent of the increase in air quality and reducing air pollutants due to vegetation is considerable, although it is estimated that around 18 million tons of air pollutants from trees are removed annually in the United States. Pollutants that favor respiratory diseases. These and other advantages (e.g. reduction in air temperature as well as psychophysiological stress and all-east-wing stress 8.9 ) were calculated to prevent 670,000 cases of acute respiratory diseases annually, with an estimated health value of $ 6.8 billion. on TB mortality in California is only one of several specific conditions that benefit from an improvement in air quality through green plants.

Other respiratory diseases can benefit from the improvement of air quality near green areas in a similar way. This is a contemporary knowledge to possibly tackle the current global covid-19 pandemic, which has also shown a connection between air pollution concentration and respiratory morbidity and mortality. To reduce coronaviruses. This strategy can be particularly effective to address problems of environmental rights and inequality between the municipalities of the urban arms and colored communities that are disproportionately affected by Covid-19, air quality problems and the lack of healthy green areas.

restrictions

This was an observation study, and therefore a causality of the tree density cannot be determined on TB mortality. In addition, the researchers rated the tree density only near the patient's residential address, not in other places such as work or school, where the participants may also have come across green space effects. However, the results of this study in connection with other research results give the existence of a strong and statistically significant inverse relationship.

FAZIT

Several factors influence the progress of infectious disease such as tuberculosis. It is known that external factors such as air pollution influence the severity of respiratory diseases. Environmental characteristics, including the density of trees that improve the air quality that surround the residence of a person, have to significantly influence the potential, state of health and the mortality rates in the entire population, especially for risk groups in sub -supplied communities.