Smoking in parents increases meningococcal disease risk

The risk of invasive meningococcal disease in children is strongly influenced by parental smoking and unfavourable socioeconomic circumstances, according to new research.

The largest increase in risk—more than eightfold—was among children of parents who both smoked, although researchers warned this may be an over estimate because such families are likely to have mul-tiple social disadvantage not covered by the study's adjustment for those factors.

The research found that children in households where 20 cigarettes a day were smoked were 2.6 times more likely to develop meningococcal disease than children in the control groups.

The study, published in the Archives of Disease in Childhood (2000;83:117-21) examined all the cases of invasive meningococcal disease diagnosed over 18 months in 35 districts of the Czech Republic. A total of 71 cases were identified in children under 15 years.

To each case, two controls were matched by age, sex, district, and place of origin (urban or rural). The controls were recruited from healthy children at the same schools as the cases. The authors said that the proportion of smoking parents was substantially higher among cases than controls.

They identified several socio-economic factors, notably maternal education, as being important in determining risk of the disease. The report also points to a number of biological possibilities put forward for a link between smoking and meningococcal disease.

The authors stated: “Exposure to smoke causes direct damage to the nasopharyngeal mucosa. Passive smoking is associated with increased risk of respiratory disease in young children.