Research

Secondhand smoke shown to damage children’s eyes

A study examining the eyes of 1,400 Hong Kong children has a drawn a link between secondhand smoke and eye damage.

According to researchers from the Chinese University of Hong Kong, children exposed to secondhand smoke from family members have, on average, a thinner choroid than those from smoke-free households.

Additionally, greater exposure to secondhand smoke, such as from multiple family members, was linked to even thinner tissue.

The research team behind the project examined children between the ages of six and eight who presented at Chinese University of Hong Kong Eye Centre between 2016 and 2017, with 459 reporting exposure to secondhand smoke.

After adjustments for age, sex, body mass index, axial length and birth weight, the team found exposure to secondhand smoke was associated with a thinner choroid by .3 μm in the central subfield, 7.2 μm in the inner inferior, 6.4 μm in the outer inferior, 6.4 μm in the inner temporal, and 7.3 μm in the outer temporal. Thinning was slightly greater among children who were exposed to multiple smokers.

“In summary, we have shown an association of secondhand smoke to thinning of choroidal thickness by 6 μm to 8 μm among children exposed to secondhand smoking at home in Hong Kong,” the report stated.

“The thinning was associated with the number of smokers in the family and the quantity of smoking, suggesting a dose-dependent relationship. While it is unknown if there is a casual relationship from this association or if this is due to confounding factors, these findings add to the potential harmful effect of secondhand smoking on children’s ocular health and development.”

While the thinning identified in the study is low compared to that seen among long-term adult smokers, the potential for long term-exposure throughout a child’s development has the potential for visual problems later in life.

The researchers also noted that further work is needed to confirm the findings, as well as the reason why certain sections of the choroid displayed greater thinning than others.

The findings were recently published in the journal JAMA Ophthalmology.