Risk Factors for Mortality among 2009 A/H1N1 Influenza Hospitalizations in Maricopa County, Arizona, April 2009 to March 2010
Table 1
Characteristics of A/H1N1 influenza hospitalizations and deaths by pandemic wave, Maricopa County, April 1, 2009 to March 31, 2010.
Variable
Total
Pandemic wave
valuea (degrees of freedom)
Spring
Fall
Age (years)
<18
246/546 (45.1)
62/144 (43.1)
184/402 (45.8)
0.045 (2)
18–49
183/546 (33.5)
41/144 (26.9)
142/402 (35.3)
≥50
117/546 (21.4)
41/144 (28.4)
76/402 (18.9)
Race/ethnicity
Hispanics
206/546 (37.7)
60/144 (41.7)
146/402 (36.3)
0.54 (5)
Whites, non-Hispanic
207/546 (37.9)
52/144 (36.1)
155/402 (38.6)
Black, non-Hispanic
62/546 (11.4)
13/144 (9.0)
49/402 (12.2)
Native American
34/546 (6.2)
9/144 (6.2)
25402 (6.2)
Asian
5/546 (0.9)
0/144 (0.0)
5/402 (1.2)
Other/unknown
32/546 (5.9)
10/144 (6.9)
22/402 (5.5)
Gender
Female
303/546 (55.5)
80/144 (55.6)
223/402 (55.5)
0.99 (1)
Male
243/546 (44.5)
64/144 (44.4)
179/402 (44.5)
Patients according to severity
ICU
153/519 (29.5)
41/140 (29.3)
112/379 (29.6)
0.95 (1)
Mechanical ventilation
106/522 (20.3)
28/144 (19.4)
78/378 (20.6)
0.76 (1)
Deaths
77/546 (14.1)
11/144 (7.6)
66/402 (16.4)
0.009 (1)
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 for age and race/ethnicity obtained from group wise comparisons, while values for gender and severity comparisons correspond to each category.
