Trends in Cardiovascular Disease Mortality by County-Level Social Vulnerability Index in the United States

Abstract

Background Although cardiovascular mortality (CVM) rates in the United States have been declining overall, our study evaluated whether this holds true for areas with increased social deprivation. Methods and Results We used county-level cross-sectional age-adjusted CVM rates (aa-CVM) (2000-2019) linked to the Centers for Disease Control and Prevention Social Vulnerability Index (SVI-2010). We grouped counties as per SVI (Groups I 0-0.2, II 0.21-0.4, III 0.41-0.6, IV 0.61-0.8, and V 0.81-1) and calculated the relative change in the aa-CVM between 2000 to 2003 and 2016 to 2019. We used adjusted linear regression analyses to explore the association between a higher SVI and temporal aa-CVM improvement; we studied this temporal change in aa-CVM across subgroups of race, sex, and location. The median aa-CVM rate (per 100 000) was 272.6 (interquartile range [IQR]: 237.5-311.7). The aa-CVM was higher in men (315.6 [IQR: 273.4-363.9]) than women (221.3 [IQR: 189.6-256.7]), and in Black residents (347.2 [IQR: 301.1-391.1]; P<0.001) than White residents (258.9 [IQR: 226-299.1]; P<0.001). The aa-CVM for SVI I (233.6 [IQR: 214.8-257.0]) was significantly lower than that of group V (323.6 [IQR: 277.2-359.2]; P<0.001). The relative reduction in CVM was significantly higher for SVI group I (32.2% [IQR: 24.2-38.4]) than group V (27.2% [IQR: 19-34.1]) counties. After multivariable adjustment, a higher SVI index was associated with lower relative improvement in the age-adjusted CVM (model coefficient -3.11 [95% CI, -5.66 to -1.22]; P<0.001). Conclusions Socially deprived counties in the United States had higher aa-CVM rates, and the improvement in aa-CVM over the past 20 years was lower in these counties.

Keywords: cardiovascular mortality; social determinants of health; social vulnerability.

Figure 1. Distribution of the Social Vulnerability Index groups in the United States.

This figure depicts the US counties according to the Social Vulnerability Index (SVI).

Figure 2. Age‐adjusted cardiovascular mortality (CVM) in the counties in the United States.

A, Age‐adjusted CMV (per 100 000) for the time period 2000 to 2003. B, Age‐adjusted cardiovascular mortality (per 100 000) for the time period 2016 to 2019. We observed that almost all counties (98.3%) reported a decline in their age‐adjusted CMV over this time.

Figure 3. The median percent relative change in age‐adjusted cardiovascular mortality (per 100 000) between 2000 to 2003 and 2016 to 2019 in counties in the United States.

We observed a median percent relative decline of 29.93 (IQR: −22.47 to 36.38) overall in the United States. CVM indicates cardiovascular mortality; and IQR, interquartile range.