Spatiotemporal Variation of the Association between Urbanicity and Incident Hypertension among Chinese Adults

Urbanization and systolic/diastolic blood pressure from a gender perspective: Separating longitudinal from cross-sectional association

There has been a generally negative view of the impact of urbanization on a rising burden of non-communicable diseases including cardiovascular disease. However, the evidence on the relationship between urbanization and cardiovascular health has remained inconclusive. A comprehensive picture of the relationship is lacking, given an implicit assumption that the longitudinal association between changes in cardiovascular health and an increasingly urbanized environment is similar between less and more urbanized communities, men and women. We used the longitudinal data on adults (18-64 years) from the China Health and Nutrition Survey (1991-2015) and employed within-between random-effects models to disaggregates the longitudinal and cross-sectional associations between urbanization and systolic/diastolic blood pressure (SBP/DBP) and examined heterogeneities in the longitudinal association by average urbanization level and gender. We found that the positive longitudinal association of urbanization with SBP/DBP was stronger in less urbanized than more urbanized communities. The cross-sectional association between urbanization and SBP was negative and significant, although the cross-sectional association between urbanization and DBP was of no statistical significance. Moreover, the positive longitudinal association between urbanization and DBP was stronger among men than women, although the gender heterogeneity in the longitudinal association of urbanization with SBP was not significant.

Thirty-Year Urbanization Trajectories and Obesity in Modernizing China

The effects of long-term urbanization changes in obesity are unclear. Data were obtained from the China Health and Nutrition Survey (CHNS) 1989-2018. A multidimensional urbanicity index was used to define the urbanization level for communities. Group-based trajectory modeling was used to identify distinct urbanization change trajectories. Gender-stratified multilevel models were used to investigate the association between urbanization trajectories and weight/BMI, through the PROC MIXED procedure, as well as the risk of being overweight + obesity (OO)/obesity (OB), through the PROC GLIMMIX procedure. A total of three patterns of the trajectory of change in urbanization were identified in 304 communities (with 1862 measurements). A total of 25.8% of communities had a low initial urbanization level and continuous increase (termed "LU"), 22.2% of communities had a low-middle initial urbanization level and constant increase (termed "LMU"), and 52.0% of communities had a middle-high initial urbanization and significant increase before 2009, followed by a stable platform since then (termed "MHU"). During the 30 follow-up years, a total of 69490 visits, contributed by 16768 adult participants, were included in the analysis. In the period, weight and BMI were observed in an increasing trend in all urbanization trajectory groups, among both men and women. Compared with LU, men living in MHU were related to higher weight, BMI, and an increased risk of OO (OR: 1.46, 95%CI: 1.26 to 1.69). No significant associations were found between urbanization trajectories and OB risk in men. Among women, the associations between urbanization and all obesity indicators became insignificant after controlling the covariates. Obesity indicators increased along with urbanization in the past thirty years in China. However, the differences among urbanization trajectories narrowed over time. More urbanized features were only significantly associated with a higher risk of obesity indicators in Chinese men. The effects of urbanization on obesity among women were buffered.