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).