Risk Factors for Mortality among 2009 A/H1N1 Influenza Hospitalizations in Maricopa County, Arizona, April 2009 to March 2010
Table 2
Rates of antiviral administration (mean and 95% confidence intervals) among A/H1N1 influenza inpatients by pandemic wave, Maricopa County, April 1, 2009 to March 31, 2010.
Variable
Total
Pandemic wave
valuea
Spring
Fall
Number of patients that received antivirals (% of total A/H1N1 cases)
361/500 (72.2)
84/142 (59.2)
277/358 (74.4)
<0.0001
Race/ethnicity
Hispanics
128/190 (67.4)
29/60 (48.3)
99/130 (76.2)
<0.0001
Whites, non-Hispanic
136/186 (73.1)
31/51 (60.8)
105/135 (77.8)
0.02
Black, non-Hispanic
46/59 (78.0)
12/13 (92.3)
34/46 (73.9)
0.16
Native American
24/30 (80.0)
6/8 (75.0)
18/22 (81.8)
0.68
Asian
4/4 (100)
0/0 (0.0)
4/4 (100.0)
N/A
Gender
Female
206/280 (73.6)
49/79 (62.0)
157/201 (78.1)
0.006
Male
155/220 (70.5)
35/63 (55.6)
120/157 (76.4)
0.002
Age (years)
<18
161/231 (69.7)
31/61 (50.8)
130/170 (76.5)
<0.0001
18–49
122/162 (75.3)
22/40 (55.0)
100/122 (82.0)
0.001
≥50
78/107 (72.9)
31/41 (75.6)
47/66 (71.2)
0.62
Patients according to severity
ICU
111/150 (74.0)
23/41 (56.1)
88/109 (80.7)
0.002
Mechanical ventilation
73/105 (69.5)
13/28 (46.4)
60/77 (77.9)
0.002
Deaths
43/63 (68.3)
5/11 (45.5)
38/52 (73.1)
0.074
Wave 1 (spring) refers to April 1 through August 15, 2009; fall wave refers to August 16, 2009 through March 31, 2010. Data are percentages of cases unless otherwise specified.
aDetermined by the Chi-square test statistic. values show the univariate comparisons of proportions between spring and fall waves.
