Climate exposure clusters and adult blood pressure in the Northern Finland Birth Cohort 1966

Abstract Introduction Climatic conditions have been associated with cardiovascular health, but most studies focus on short term exposure and individual weather parameters. The aim of the present work is to explore the use of longitudinal multidimensional clustering in studying the relationship between climate exposure over the life-course and adult blood pressure (BP). Methods An array of 7 climate parameters (annual averages) was linked to health data from the Northern Finland Birth Cohort 1966, using geolocations from their residential history. Only participants living in Finland during the entire study period (1970-2011) were included (n = 4191). Individual climate trajectories were clustered using the kml3d algorithm across youth (4-24y) and adult (25-46y) life stages. Generalized linear models were used to assess the relationship between climate clusters and clinically measured systolic BP (SBP) and diastolic BP (DBP) at 46 years. All models were adjusted for known predictors of environmental exposure and BP. Results Two youth climate clusters (A and B) were identified, while three clusters (A, B and C) emerged in adulthood. Compared to reference cluster A, B describes a colder northern climate, while C represents a transition to a warmer southern climate. Preliminary results show that adult exposure to this warmer southern climate (C) is associated with lower SBP (-4.63 mmHg, 95%CI -6.01,-3.25) and DBP (-1.98mmHg, 95%CI -2.93,-1.03). Likewise, growing up in a colder climate (B) was suggested to be associated with lower SBP (-1.21mmHg, 95%CI -2.28,-0.15) but not DBP (-0.37 95%CI -2.25,-0.15). Conclusions Youth and adult climate exposure were independently associated with adult BP. Studies including individuals raised in southern Finland are needed to assess whether changes in climate exposure play a role. Our results show that kml3d clustering can identify distinct climate clusters at country level, facilitating observational studies on climate exposure. Key messages • We analyzed climate exposure clusters with blood pressure in a Finnish birth cohort. Results suggest that youth and adulthood exposure are associated with adult blood pressure independently. • The kml3d algorithm identified distinct climate exposure clusters at the national level in 7 climate variables over 42 years, enabling future studies on long-term climate exposure.