An article published in the journal Tobacco Control reports that children who are exposed to second hand tobacco smoke have an increased risk of severe infectious diseases that require hospital admission. In addition to respiratory illnesses, these children were more likely to be admitted for a range of infectious diseases, such as meningococcal disease. The most harm was noted for children who were exposed in the first few months of life, particularly those born prematurely or with low birth weight.

To arrive at these findings, researchers studied 7,402 children born in Hong Kong in April and May 1997. They investigated the association between second hand smoke exposure and hospital admission for any infectious illness during the first eight years of life.

The greatest risk of hospital admission was seen in children who lived in the same house as someone who smoked within three meters of them during their first few months of life – 33% were admitted within the first year of life. Researchers found a 45% increase in the likelihood of being admitted because of an infectious disease in those with exposure to second hand smoke during the first 6 months of life.

Infants with low birth weights were 75% more likely to be admitted and those who were premature were 2 times as likely to be admitted – significantly increased risks of hospitalization after exposure for these vulnerable infants.

Second hand smoke, the authors suggest, is not only affecting the respiratory system, but also the immune system: “An excess risk of severe morbidity from both respiratory and other infections for all infants exposed to second hand smoke suggests that such exposure, as well as acting via direct contact with the respiratory tract, may also affect the immune system,” they write.

They conclude that, “Reducing household SHS [second hand smoke] exposure in infants and particularly in more vulnerable infants can reduce infectious morbidity and corresponding hospital use. Policy options to protect infants and children from household SHS exposure should be implemented.”

Early life second hand smoke exposure and serious infectious morbidity during the first 8 years: evidence from Hong Kong’s ”Children of 1997” birth Cohort
M K Kwok, C M Schooling, L M Ho, S S L Leung, K H Mak, S M McGhee, T H Lam, G M Leung
Tobacco Control (2008)
doi:10.1136/tc.2007.023887
Click Here to View Abstract

Written by: Peter M Crosta