Counties included in our analytic cohort tended to be younger, wealthier, have fewer racial and ethnic minorities, and have fewer uninsured relative to the national average of all counties (Table 1).
Table 1
County Characteristics and the Adjusted Association Between 2008 to 2016 Per Capita Local Public Health Department Spending and Percentage Point Differences in County-level (a) 2008 Sociodemographics and (b) 2008 to 2016 Sociodemographic Shifts
| County-level demographics | Changes in per capita spending |
Sociodemographic characteristics | Characteristics of all US counties in 2008 (N=3005), mean (SD) | Characteristics of sampled counties in 2008 (N=793), mean (SD) | Based on 2008 sociodemographics† (95% CI) | Based on 2008 to 2016 sociodemographic shifts‡ (95% CI) |
% over 65 years old | 16.1 (4.2) | 15.8 (4.2) | + $0.53* (+ $0.01 to + $1.06) | - $2.79*** (- $4.18 to - $1.40) |
% Black | 8.3 (14.0) | 7.3 (12.1) | + $0.00 (- $0.16 to + $0.17) | - $0.40 (- $2.39 to + $1.58) |
% Hispanic | 8.5 (13.5) | 7.2 (10.3) | + $0.02 (- $0.19 to + $0.22) | + $0.56 (- $1.09 to + $2.21) |
% in poverty | 15.1 (6.0) | 13.9 (5.2) | - $0.39 (- $1.10 to + $0.32) | - $0.08 (- $1.20 to + $1.04) |
% unemployed | 5.8 (2.1) | 6.0 (1.8) | - $1.31* (- $2.34 to - $0.27) | - $0.01 (- $1.26 to + $1.25) |
% uninsured | 14.3 (4.7) | 12.9 (40.0) | - $0.14 (- $0.70 to + $0.41) | - $0.55 (- $1.20 to + $0.10) |
†All reported values were from the same linear model, which included each of the 2008 county-level sociodemographic characteristics (percent over 65 years old, Black, Hispanic, in poverty, unemployed, and uninsured) and were additionally adjusted for baseline per capita spending in 2008, the median household income within a county, and a binary determination rurality.
‡All reported values were from the same linear model, which included 2008 to 2016 shifts in county-level sociodemographic characteristics (percent over 65 years old, Black, Hispanic, in poverty, unemployed, and uninsured) and were additionally adjusted for baseline per capita spending in 2008, shifts in the median household income within a county from 2008 to 2016, and a binary determination of rurality.
*p<0.05; **p<0.01; ***p<0.001
County-level, 2008 sociodemographic characteristics associated with changes in per capita LPHD spending included age and the unemployment rate (Table 1). For every additional percentage point in the proportion of a county over 65 years old, per capita spending increased by an estimated +$0.53 (95% CI: +$0.01 to +$1.06) and for every additional percentage point in the proportion of the population who was unemployed, per capita spending decreased by $1.31 (95% CI: -$2.34 to -$0.27).
When evaluating the association between 2008 to 2016 demographic shifts with changes in per capita LPHD spending, only an increase in the proportion of the population that was 65 years or older was statistically significant. For every additional percentage point, per capita spending decreased by -$2.79 (95% CI: -$4.18 to -$1.40).