In France, the use of paracetamol has increased by 50% in 10 years and its active agent, acetaminophen remains the most widely used analgesic. The use of paracetamol during pregnancy and in infants is already documented as linked to a whole range of risks, this study warns of a new risk in the event of exposure in infants: an increased risk of asthma and respiratory problems in adolescence. This study from the University of Melbourne (Australia), presented at the 2018 Congress of the European Respiratory Society, deciphers the responsible process and identifies specific variants of GST genes that increase susceptibility to lung problems.
Thus, children who take paracetamol during the first 2 years of life and carry certain variants may be at greater risk of suffering from asthma before the age of 18. However, the researchers demonstrate here an association - and not a causal relationship - between the use of paracetamol and the onset of asthma in adolescence, in particular in subjects carrying a particular variant of the gene. glutathione S-transferase (GSTP1).
The study is conducted among 620 children followed from birth to 18 years as part of the Melbourne Atopy cohort. These children recruited before their birth because considered to be at high risk of developing an allergic disease, due to family history, were evaluated every 4 weeks after birth for the first 15 months of life, then at 18 months and at 2 years for taking paracetamol. At the age of 18, the researchers analyzed a sample of blood or saliva for variants of the GST genes: GSTT1, GSTM1 and GSTP1 and for the possible diagnosis of asthma via a spirometry test. This analysis shows that:
- Childhood paracetamol consumption in subjects carrying a variant of the GSTP1 gene, GSTP1 Ile/Ile is associated with an 80% increased risk of developing asthma.
- in contrast, increased exposure to paracetamol in children with other types of GST variants does not impact asthma risk.
- other effects are identified in children who have a variant of GSTM1, part of which does not work. In these children, the use of paracetamol appears to be associated with a small but significant reduction in the quantity of expired air, therefore with a change in pulmonary function. But the researchers don't know if this change is clinically important.
One possible explanation: GST genes contain the instructions to make enzymes that use an antioxidant called glutathione to "absorb" the effects of toxin exposure in the body and lungs. This mechanism helps prevent cell damage and inflammation. But paracetamol consumes glutathione and in doing so reduces the body's ability to manage exposure to toxic substances, explained lead author Ms Dai, a nurse in the Allergy and Lung Health Unit at the University of Melbourne .
The study thus presents very preliminary evidence of a harmful effect of paracetamol in infants on respiratory health in the event of particular genetic profiles. But beware, the association could be linked to confounding factors, including lower respiratory tract infections caused by viruses in infants treated with paracetamol…Further research is therefore needed to confirm these findings.
NB Nestlé supported this study