Residential greenness during the entire pregnancy and in different trimesters and the risk of asthma
Distribution of the mean values of cumNDVI within 100 m, 300 m, 500 m, and 1000 m of the participant’s residence during different time periods of pregnancy are presented in Table 4.
Figure 2 and Table S3 show the aHR of asthma in relation to the cumulative exposure to NDVI during different time periods of pregnancy. Increased residential greenness during the entire pregnancy was associated with an increased risk of asthma at 6 years of age with an aHR of 1.61 (95% CI: 1.08, 2.41) per 1 unit increase in NDVI, but the effect was somewhat weaker by 12 years and 27 years of age (Figure 2). The risk of asthma was significantly related to the increased greenness during the third trimester, with an aHR of 2.37 (95% CI: 1.36, 4.14) per 1 unit increase in cumNDVI, and the risk was significantly increased in relation to the highest quartile of the mean cumNDVI (aHR=1.57; 95% CI: 1.04, 2.36) (Table S3). The effect estimates during the third trimester were somewhat weaker and non-significant at the age of 12 years with an aHR of 1.47 (95% CI: 0.96, 2.26) and at the age of 27 years with an aHR of 1.24 (95% CI: 0.85, 1.82) per 1 unit increase in cumNDVI (Figure 2).