Conceived and designed the experiments: YCM, TCL, JGL. Analyzed the data:
SYY, HJC. Contributed reagents/materials/analysis tools: CCL, TCL, JGL. Wrote the paper: YCM, TCL.
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Figure 1. Time trends in the prevalence of TCM use among asthma prevalent and incident patients
Figure 2. Time trends in the prevalence of asthma stratified by (A) sex (B) age (C) insurance premium (D) urbanization level
Figure 3. Time trends in the incidence of asthma stratified by (A) sex (B) age (C) insurance premium (D) urbanization level
Table 1. Prevalence and incidence of asthma in Taiwan
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 Prevalence rates of asthma
Prevalent cases 56,885 60,593 64,266 67,709 70,195 75,081 78,767 82,551 86,650 91,096 95,952 101,535 Age (year) 55.1±18.7 55.4 ±19.0 55.9±19.4 56.6±19.6 57.1±19.9 57.2±20.4 57.4±20.8 57.6±21.2 57.6±21.8 57.5±22.3 57.3±22.9 57.1±23.4 Age at death (year) 68.2±20.0 72.9 ±14.0 74.7±12.0 75.2±12.1 76.6±11.4 75.8±12.9 75.3±13.5 76.4±13.4 76.5±14.3 76.7±13.5 76.7±15.0 76.9±15.2 Total population 751,514 758,012 773,155 773,213 770,002 799,830 814,823 827,555 841,577 854,044 867,049 880,902
Prevalence rate (%) 7.57 7.99 8.31 8.76 9.12 9.39 9.67 9.98 10.30 10.67 11.07 11.53
Standardized prevalence rate
(%) 7.57 7.84 8.02 8.23 8.43 8.65 8.86 9.08 9.35 9.69 10.09 10.57
Prevalence of TCM use (%) 38.58 37.29 35.27 34.64 34.72 33.01 31.23 31.41 30.84 31.24 29.86 29.26
Age
18–30 2.84 3.20 3.55 4.01 4.54 5.14 5.84 6.62 7.60 8.78 10.24 11.85
30–40 4.24 4.36 4.28 4.30 4.21 4.19 4.15 4.17 4.22 4.39 4.56 4.82
40–50 6.28 6.48 6.58 6.59 6.63 6.67 6.66 6.59 6.54 6.54 6.48 6.47
50–60 9.73 9.79 9.67 9.66 9.68 9.67 9.57 9.62 9.52 9.43 9.33 9.29
60 19.75 20.33 20.86 21.27 21.58 21.86 22.06 22.12 22.11 21.99 21.88 21.72
Sex
Female 7.79 8.25 8.56 8.95 9.33 9.62 9.91 10.24 10.59 10.99 11.42 11.91
Male 7.36 7.75 8.08 8.56 8.90 9.16 9.43 9.72 10.01 10.35 10.73 11.16
Insurance premium
0–20,000 8.33 8.76 9.14 9.74 10.21 10.56 10.89 10.38 10.69 11.10 11.55 12.07
20,000–40,000 5.98 6.45 6.56 6.93 7.34 7.60 7.93 10.18 10.52 10.86 11.29 11.76
40,000–60,000 6.62 7.08 7.42 7.71 7.85 7.88 8.17 8.39 8.65 8.97 9.30 9.76
60,000 10.05 7.47 7.87 8.05 8.29 8.80 9.04 9.35 9.62 10.08 10.29 10.56
Urbanization level
High-density urban area 5.78 6.25 6.56 6.82 7.20 7.49 7.83 8.18 8.56 8.95 9.38 9.92
Medium-density urban area 7.24 7.52 7.87 8.52 8.82 9.07 9.28 9.58 9.86 10.26 10.67 11.09
Newly developed area 7.42 7.92 8.15 8.69 9.01 9.29 9.50 9.75 10.09 10.44 10.74 11.16
General area 9.77 10.33 10.65 11.1 11.44 11.77 12.08 12.42 12.68 12.97 13.40 13.83
Aging society area 12.51 12.69 13.32 13.42 14.10 14.41 14.72 15.04 15.33 15.62 16.11 16.53
Rural area 13.05 13.70 14.14 14.19 14.64 14.87 15.26 15.68 15.88 16.35 16.88 17.46
Non-developed area 10.73 11.23 11.55 11.80 12.33 12.83 13.05 13.29 13.54 13.84 14.11 14.66
Table 2. Multivariate-adjusted relative risk of annual prevalence of asthma rates for sex, age, time, insurance premium, and urbanization level
Variable Crude prevalence ratio
2001 1.06 (1.05, 1.06)*** 1.04 (1.03, 1.05)***
2002 1.10 (1.09, 1.11)*** 1.07 (1.06, 1.08)***
2003 1.16 (1.15, 1.17)*** 1.10 (1.09, 1.11)***
2004 1.20 (1.20, 1.21)*** 1.13 (1.12, 1.14)***
2005 1.24 (1.23, 1.25)*** 1.16 (1.15, 1.16)***
2006 1.28 (1.27, 1.29)*** 1.18 (1.17, 1.19)***
2007 1.32 (1.31, 1.33)*** 1.20 (1.19, 1.21)***
2008 1.36 (1.35, 1.37)*** 1.22 (1.21, 1.23)***
2009 1.41 (1.40, 1.42)*** 1.25 (1.24, 1.25)***
2010 1.46 (1.45, 1.47)*** 1.27 (1.26, 1.28)***
2011 1.52 (1.51, 1.53)*** 1.30 (1.29, 1.31)***
Sex
Female 1.00 1.00
Male 0.95 (0.94, 0.95)*** 0.93 (0.92, 0.93)***
Age
18–30 1.00 1.00
30–40 0.73 (0.72, 0.73)*** 0.72 (0.72, 0.73)***
40–50 1.10 (1.09, 1.11)*** 1.09 (1.08, 1.09)***
50–60 1.61 (1.60, 1.61)*** 1.57 (1.56, 1.57)***
60 3.62 (3.61, 3.64)*** 3.44 (3.43, 3.46)***
Insurance premium
0–20,000 1.00 1.00
20,000–40,000 0.92 (0.92, 0.93)*** 1.00 (0.99, 1.00) 40,000–60,000 0.81 (0.81, 0.81)*** 0.99 (0.98, 0.99)***
≥60,000 0.91 (0.91, 0.92)*** 1.02 (1.01, 1.02)***
Urbanization level
High-density urban area 1.00 1.00
Medium-density urban area 1.18 (1.18, 1.19)*** 1.15 (1.15, 1.16)***
Newly developed area 1.20 (1.19, 1.20)*** 1.19 (1.18, 1.19)***
General area 1.53 (1.52, 1.53)*** 1.30 (1.29, 1.30)***
Aging society area 1.86 (1.85, 1.88)*** 1.28 (1.27, 1.30)***
Rural area 1.95 (1.94, 1.96)*** 1.42 (1.41, 1.43)***
Non-developed area 1.64 (1.63, 1.65)*** 1.31 (1.30, 1.32)***
***: p<0.001.
Table 3. Multivariate-adjusted relative risk of annual incidence rates of t asthma for sex, age, time, insurance premium, and urbanization level
Variable Crude relative risk
2001 0.93 (0.90, 0.96)*** 0.90 (0.88, 0.93)***
2002 0.72 (0.69, 0.74)*** 0.69 (0.67, 0.72)***
2003 0.62 (0.59, 0.64)*** 0.58 (0.56, 0.60)***
2004 0.67 (0.65, 0.70)*** 0.62 (0.59, 0.64)***
2005 0.66 (0.64, 0.69)*** 0.60 (0.58, 0.62)***
2006 0.56 (0.54, 0.58)*** 0.51 (0.49, 0.52)***
2007 0.57 (0.55, 0.59)*** 0.49 (0.47, 0.51)***
2008 0.52 (0.51, 0.54)*** 0.44 (0.43, 0.46)***
2009 0.53 (0.51, 0.55)*** 0.44 (0.42, 0.46)***
2010 0.53 (0.51, 0.55)*** 0.43 (0.42, 0.45)***
2011 0.63 (0.61, 0.65)*** 0.50 (0.49, 0.52)***
Sex
Female 1.00 1.00
Male 0.81 (0.80, 0.82)*** 0.80 (0.78, 0.81)***
Age
18–30 1.00 1.00
30–40 1.25 (1.22, 1.29)*** 1.31 (1.27, 1.35)***
40–50 1.48 (1.44, 1.53)*** 1.58 (1.53, 1.63)***
50–60 2.34 (2.27, 2.41)*** 2.56 (2.48, 2.64)***
60 4.34 (4.23, 4.46)*** 4.69 (4.57, 4.82)***
Insurance premium
0–20,000 1.00 1.00
20,000–40,000 0.91 (0.89, 0.92)*** 1.12 (1.10, 1.15)***
40,000–60,000 0.87 (0.85, 0.89)*** 1.05 (1.03, 1.08)***
≥60,000 0.85 (0.82, 0.88)*** 1.01 (0.97, 1.05) Urbanization level
High-density urban area 1.00 1.00
Medium-density urban area 1.11 (1.09, 1.13)*** 1.11 (1.08, 1.13)***
Newly developed area 1.05 (1.03, 1.08)*** 1.06 (1.03, 1.08)***
General area 1.35 (1.31, 1.38)*** 1.18 (1.15, 1.21)***
Aging society area 1.51 (1.43, 1.59)*** 1.09 (1.03, 1.15)***
Rural area 1.65 (1.58, 1.71)*** 1.27 (1.22, 1.32)***
Non-developed area 1.42 (1.37, 1.48)*** 1.19 (1.15, 1.24)***
***: p<0.001.
Year
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
Prevalence of TCM use
0 % 10 % 20 % 30 % 40 % 50 % 60 % 70 %
asthma prevalence patients asthma incidence patients
Figure 1 Time trends in the prevalence of TCM use among asthma prevalent and incident patients
Year
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 0
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 0
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 0
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 0
Figure 2 Time trends in the prevalence of asthma stratified by (A) sex (B) age (C) insurance premium (D) urbanization level
(A) Sex (B) Age
(C) Insurance premium Year (D) Urbanization level
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 0.0
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 0.0
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 0.0
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 0.0