Table 1
Data source.
| VARIABLES | PERIOD | CONSTANT | SOURCE |
|---|---|---|---|
| Mortality from Ischemic Heart Diseases (IHD) | 2018–2022 | 100.000 | 27 |
| Population | 2018–2022 | 100.000 | 32 |
| Electrocardiograph rate | 2018–2022 | 10.000 | 33 |
| Cardiac catheterization rate | 2018–2022 | 10.000 | 34 |
| Access index to hemodynamics | 2018–2022 | E2SFCA | 33 |
| Access index of pre-hospital mobile units | 2018–2022 | E2SFCA | 33 |
| Cardiologists rate | 2018–2022 | 1.000 | 33 |
| Myocardial scintigraphy rate | 2018–2022 | 10.000 | 34 |
| Stress test rate | 2018–2022 | 10.000 | 34 |
| Stress echocardiogram rate | 2018–2022 | 10.000 | 34 |
| Shapefile from southern Brazil | 2022 | 1191 | 35 |
Table 2
Number of deaths attributed to IHD in subjects aged 30 to 70 years in the Southern region of Brazil, 2018–2022.
| VARIABLES | SOUTH REGION N = 59,093 | |||
|---|---|---|---|---|
| PARANÁ N = 21,565 (36.5%) | SANTA CATARINA N = 13,296 (22.5%) | RIO GRANDE DO SUL 24,232 (41.0%) | TOTAL N = 59,093 (100%) | |
| Gender | ||||
| Male | 14,171 (65.7%) | 9,034 (68.0%) | 15,657 (64.6%) | 38,859 (65.8%) |
| Female | 7,394 (34.3%) | 4,262 (32.0%) | 8,575 (35.4%) | 20,230 (34.2%) |
| Race | ||||
| White | 16,299 (75.6%) | 11,894 (89.5%) | 20,721 (85.5%) | 48,912 (82.8%) |
| Non-white | 5,266 (24.4%) | 1,402 (10.5%) | 3,511 (14.5%) | 10,181 (17.2%) |
| Age group (years) | ||||
| 30–40 | 448 (2.1%) | 241 (1.8%) | 362 (1.5%) | 1,051 (1.8%) |
| 40–50 | 1,590 (7.4%) | 970 (7.3%) | 1,403 (5.8%) | 3,962 (6.7%) |
| 50–60 | 4,137 (19.2%) | 2,761 (20.8%) | 4,105 (16.9%) | 10,999 (18.6%) |
| 60–70 | 15,390 (71.4%) | 9,324 (70.1%) | 18,362 (75.8%) | 43,081 (72.9%) |

Figure 1
Spatial distribution of IHD mortality rates in the 1,191 municipalities of southern Brazil, and their clusters. 1A. IHD mortality rates per adjusted population/100,000 inhabitants in Southern Brazil, 2018 to 2022; 1B. Analysis of Local Indicators of Spatial Association (LISA) indicating clusters according to distribution patterns of high and low IHD mortality rates.

Figure 2
Bivariate Local Moran of ischemic heart disease (IHD) in the south region of Brazil.
Table 3
Results of global and local multivariate analysis of IHD mortality rates of municipalities in southern Brazil.
| OLS | GWR | RF | GWRF | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| VARIABLE | COEFFICIENT | Std. ERROR | T-VALUE | PROBABILITY (>|t|) | MIN | 1 st QU | MEDIAN | 3RD QU | MAX | MIN | MAX | MEAN | Std | MIN | MAX | MEAN | Std |
| Electrocardiograph rate | –1.062 | 0.217 | –4.879 | 0.000*** | –2.387 | –1.035 | –0.407 | 0.220 | 2.745 | 3744.675 | 99887.77 | 99959.000 | 19040.083 | 0.364 | 3239.136 | 270.614 | 425.543 |
| Cardiac catheterization rate | 0.229 | 0.065 | 3.500 | 0.000*** | –1.441 | 0.021 | 0.203 | 0.410 | 1.232 | 4755.092 | 30693.36 | 14577.569 | 5217.347 | 0.246 | 7015.351 | 319.890 | 598.804 |
| Access index to hemodynamics | –1.594 | 0.478 | –3.330 | 0.000*** | –23.272 | –2.723 | –0.959. | 0.613 | 6.248 | 4150.982 | 30591.54 | 12584.163 | 5614.0434 | 0.000 | 4039.209 | 277.454 | 460.952 |
| Access index of pre-hospital mobile units | –0.090 | 0.042 | –2.148 | 0.031* | –2.275 | –0.320 | –0.034 | 0.107 | 0.910 | 3988.512 | 30506.97 | 13369.577 | 5293.7682 | 0.156 | 4500.410 | 307.706 | 510.182 |
| Cardiologists rate | –6.409 | 2.429 | –2.639 | 0.008** | –35.999 | –8.610 | –2.799 | 1.230 | 16.051 | 1988.913 | 9959.448 | 5098.821 | 1665.442 | 0.000 | 4643.060 | 140.773 | 339.669 |
| Myocardial scintigraphy rate | 0.189 | 0.462 | 0.410 | 0.681 | –25.294 | –2.034 | 0.137 | 1.464 | 20.759 | 370.279 | 11722.93 | 3081.451 | 2522.169 | 0.000 | 2510.193 | 56.666 | 184.920 |
| Stress test rate | 3.065 | 1.197 | 2.560 | 0.010* | –273.639 | –6.438 | 0.912 | 5.158 | 400.816 | 62.118 | 6995.904 | 2214.965 | 1598.3471 | 0.000 | 1426.459 | 36.062 | 122.344 |
| Stress echocardiogram rate | –1.082 | 0.893 | –1.212 | 0.225 | –50.319 | –1.381 | 0.478 | 3.015 | 26.689 | 683.792 | 5482.294 | 2125.966 | 964.8613 | 0.000 | 2581.386 | 38.119 | 177.638 |
| R2 | 0.066 | 0.656 | 0.058 | 0.983 | |||||||||||||
| Aicc | 10034.81 | 9074.02 | 4550.3 | 2298.4 | |||||||||||||
| Moran Residues | 0.694 | 0.408 | 0.500 | –0.151 | |||||||||||||
[i] Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1.

Figure 3
Importance of the variable according to the incMSE.

Figure 4
Spatial distribution of predictor variables’ importance in the GWRF model.

Figure 5
Ischemic heart disease mortality rates predicted using GWRF.

Figure 6
Determination coefficients of validation and test data using Geographically Weighted Random Forest to predict IHD Mortality Rate.
