PON1 and asthma: Sub-group analysis showed that asthma-associated PON-1 reduction was significant in children (SMD = −1.85, 95% CI 3.11 to −0.59, p = 0.004) but not in adults (SMD = −1.30, 95% CI −2.65 to 0.05, p = 0.06) (Fig. 5).