Table 2.
Distribution of acute heatwaves and ED visit data used in acute heat wave analysis ( consecutive elevated HI days) in Anchorage, Fairbanks, and the Matanuska-Susitna Valley, Alaska, 2015–2019.
| Total | HI threshold | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 21.1°C (70°F) | 22.2°C (72°F) | 23.3°C (74°F) | 24.4°C (76°F) | 25.6°C (78°F) | 26.7°C (80°F) | 27.8°C (82°F) | 28.9°C (84°F) | 30°C (86°F) | ||
| Number of acute heat wave days above each HI threshold by study area | ||||||||||
| Anchorage [ (%)] | 460 (100) | 126 (27.4) | 94 (20.4) | 67 (14.6) | 44 (9.6) | 24 (5.2) | 14 (3.0) | 4 (0.9) | 0 (0.0) | 0 (0.0) |
| Fairbanks North Star [ (%)] | 460 (100) | 189 (41.1) | 145 (31.5) | 115 (25.0) | 78 (17.0) | 58 (12.6) | 36 (7.8) | 13 (2.8) | 4 (0.9) | 0 (0.0) |
| Matanuska-Susitna [ (%)] | 460 (100) | 110 (23.9) | 78 (17.0) | 57 (12.4) | 33 (7.2) | 17 (3.7) | 11 (2.4) | 6 (1.3) | 2 (0.4) | 0 (0.0) |
| Number of ED visits on acute heat wave days by health outcome | ||||||||||
| Asthma [ (%)] | 2,911 (100) | 899 (30.9) | 687 (23.6) | 516 (17.7) | 357 (12.3) | 232 (8.0) | 146 (5.0) | 58 (2.0) | 9 (0.3) | 0 (0.0) |
| COPD [ (%)] | 2,158 (100) | 620 (28.7) | 462 (21.4) | 335 (15.5) | 215 (10.0) | 113 (5.2) | 58 (2.7) | 18 (0.8) | 5 (0.2) | 0 (0.0) |
| Pneumonia [ (%)] | 2,081 (100) | 558 (26.8) | 407 (19.6) | 302 (14.5) | 202 (9.7) | 137 (6.6) | 82 (3.9) | 34 (1.6) | 4 (0.2) | 0 (0.0) |
| Bronchitis [ (%)] | 1,972 (100) | 521 (26.4) | 388 (19.7) | 273 (13.8) | 166 (8.4) | 98 (5.0) | 63 (3.2) | 17 (0.9) | 7 (0.4) | 0 (0.0) |
| Arrhythmia [ (%)] | 1,617 (100) | 483 (29.9) | 351 (21.7) | 256 (15.8) | 159 (9.8) | 94 (5.8) | 44 (2.7) | 16 (1.0) | 4 (0.2) | 0 (0.0) |
| Cerebrovascular [ (%)] | 434 (100) | 129 (29.7) | 96 (22.1) | 73 (16.8) | 51 (11.8) | 35 (8.1) | 19 (4.4) | 7 (1.6) | 1 (0.2) | 0 (0.0) |
| Ischemic [ (%)] | 200 (100) | 65 (32.5) | 54 (27.0) | 44 (22.0) | 28 (14.0) | 14 (7.0) | 8 (4.0) | 4 (2.0) | 0 (0.0) | 0 (0.0) |
| Myocardial infarction [ (%)] | 81 (100) | 32 (39.5) | 24 (29.6) | 18 (22.2) | 14 (17.3) | 4 (4.9) | 2 (2.5) | 1 (1.2) | 0 (0.0) | 0 (0.0) |
| Heart failure [ (%)] | 441 (100) | 120 (27.2) | 85 (19.3) | 64 (14.5) | 43 (9.8) | 26 (5.9) | 15 (3.4) | 6 (1.4) | 2 (0.5) | 0 (0.0) |
| Heat illness [ (%)] | 35 (100) | 30 (85.7) | 27 (77.1) | 25 (71.4) | 24 (68.6) | 19 (54.3) | 15 (40.0) | 7 (20.0) | 2 (5.7) | 0 (0.0) |
Note: In this analysis, an acute heat wave day was one when the HI exceeded the indicated threshold, as did the previous day (i.e., an acute heat wave occurred if there were at least two elevated HI days in a row.) COPD, chronic obstructive pulmonary disease; ED, emergency department; HI, heat index.