1. General characteristics
The mean age of participants with hypertension was 60 years. About half of them were men (50.4%) and 58.5% were from rural areas. Table 1 presents their demographic characteristics, behavioral risk factors, and weight status. Rates of smoking and alcohol consumption were significantly higher in men than in women (p < 0.001). Women had a higher obesity (BMI ≥ 28kg/m2) prevalence (22.6% vs. 18.4%) than men (p = 0.01).
Table 1. Demographic characteristics of Chinese adults with hypertension based on China Health and Nutrition Survey 2011
|
All
|
Women
|
Men
|
P-value**
|
Sample size (N)
|
3,579
|
1,775
|
1,804
|
|
Age (year, mean±SD)
|
60.0±12.4
|
61.6±11.7
|
58.5±12.9
|
< 0.001
|
BMI (kg/m2)
|
25.3±5.4
|
25.4±5.2
|
25.2±5.6
|
0.13
|
Residence (%)
|
|
|
|
|
Urban
|
41.5
|
41.5
|
41.5
|
1.0
|
Rural
|
58.5
|
58.5
|
58.5
|
|
Geographic region† (%)
|
|
|
|
0.33
|
Western China
|
20.1
|
21.1
|
19.1
|
|
Eastern China
|
49.4
|
48.6
|
50.3
|
|
Central China
|
30.5
|
30.3
|
30.6
|
|
Marital status* (%)
|
|
|
|
< 0.001
|
Married
|
83.2
|
76.0
|
90.3
|
|
Single
|
16.8
|
24.0
|
9.7
|
|
Ethnicity
|
|
|
|
1.0
|
Han
|
92.0
|
92.0
|
90.0
|
|
Minority
|
8.0
|
8.0
|
8.0
|
|
Occupational status (%)
|
|
|
|
< 0.001
|
Employed
|
44.1
|
32.1
|
56.0
|
|
Unemployed
|
55.9
|
67.9
|
44.0
|
|
Health insurance (%)
|
|
|
|
|
Insured
|
95.8
|
95.9
|
95.7
|
0.82
|
Not insured
|
4.2
|
4.1
|
4.3
|
|
Education (%)
|
|
|
|
< 0.001
|
≤ Elementary school
|
48.2
|
60.8
|
35.7
|
|
Middle school
|
27.4
|
22.4
|
32.4
|
|
High school
|
17.1
|
13.0
|
21.1
|
|
≥ College
|
7.3
|
3.8
|
10.8
|
|
Smoking (%)
|
|
|
|
< 0.001
|
Non-smoker
|
65.9
|
94.3
|
38.0
|
|
Ex-smoker
|
6.4
|
0.8
|
11.8
|
|
Smoker
|
27.7
|
4.9
|
50.2
|
|
Alcohol consumption (%)
|
|
|
|
< 0.001
|
Drinking
|
34.5
|
8.7
|
59.9
|
|
Not drinking
|
65.5
|
91.3
|
40.1
|
|
Weight status (%)
|
|
|
|
0.01
|
Normal weight (18.5≤BMI<24)
|
36.4
|
36.0
|
36.8
|
|
Underweight (BMI<18.5)
|
2.2
|
2.3
|
2.0
|
|
Overweight (24≤BMI<28)
|
41.0
|
39.1
|
42.8
|
|
Obese (BMI≥28)
|
20.5
|
22.6
|
18.4
|
|
Hypertension was defined as having an average systolic blood pressure BP ≥ 140 mmHg, diastolic blood pressure ≥ 90mmHg, self-reported being previously diagnosed as hypertension by a physician or taking antihypertension drugs currently;
Non-smoker was defined as subjects who responded negatively to “have you ever smoked cigarettes?”; ex-smoker was defined as subjects who responded positively to questions “have you ever smoked cigarettes?” but negatively to “do you still smokes cigarettes?”; current smoker was defined as subjects who responded both positive answers to questions “have you ever smoked cigarettes?” and “do you still smokes cigarettes?”; drinking refers to subject who regularly drink alcohol since last year.
*Single includes never married, divorced, widowed and separated;
†Western China includes Guangxi, Guizhou and Chongqing; Eastern China includes Shanghai, Beijing, Jiangsu, Liaoning and Shandong; Central China includes Henan, Hubei, Henan and Heilongjiang;
**p-value was calculated from t-test for continuous variables and chi-square test for categorical variables.
2. Awareness, treatment, and control of hypertension
Overall, 27.6% of Chinese adults had hypertension in the sample, and the hypertension prevalence were 29.5% and 25.8% in men and women (p<0.001), respectively. The estimated prevalence of awareness, treatment, and control were 55.7%, 46.5%, and 20.3% among Chinese adults with hypertension, respectively. The prevalence of awareness and treatment were higher in women compared to men, but the prevalence of hypertension control was higher in men than in women (Figure 1).
Of those who were aware of their hypertension status, 83.0% (n = 1,664) received antihypertensive treatment. In addition, 43.8% (n = 728) of those who received treatment had their blood pressure under control (SBP/DBP < 140/90 mmHg).
Table 2 presents the proportions of hypertension outcomes in different subgroups. Older adults (≥ 65 yrs) had higher hypertension awareness and treatment rates compared to young adults (18-49 yrs). Hypertension awareness, treatment and control rates were higher in urban areas compared to rural areas and were higher in Eastern China compared to Central China. Participants who had a higher educational attainment (high school and above) were more likely to be aware of hypertension, and got treated and controlled. In contrast, participants who were ethnic minorities and obese were less likely to have controlled hypertension.
Table 2. Proportion¶ (%) of hypertension awareness, treatment, and control among Chinese adults with hypertension (HTN) based on CHNS 2011
|
Awareness
(1,993)
|
Treatment
(1,664)
|
Control
(728)
|
HTN
|
Awarenessa
|
HTN
|
Treatedb
|
Age group (years)
|
|
|
|
|
|
18-49
|
36.2
|
25.9
|
71.7
|
12.7
|
49.0
|
50-64
|
58.1**
|
48.6**
|
83.6**
|
22.2**
|
45.7
|
65+
|
64.8**
|
56.8**
|
87.6**
|
22.8**
|
32.9
|
Residence
|
|
|
|
|
|
Rural
|
48.0
|
38.4
|
80.0
|
13.5
|
35.2
|
Urban
|
66.6**
|
58.0**
|
87.0**
|
30.0**
|
51.7**
|
Geographic region†
|
|
|
|
|
|
Central China
|
50.1
|
39.6
|
79.0
|
13.3
|
33.6
|
Western China
|
47.2
|
39.1
|
82.9
|
15.7
|
40.2
|
Eastern China
|
62.6**
|
53.8**
|
85.1**
|
26.6**
|
49.4**
|
Ethnicity
|
|
|
|
|
|
Han
|
56.7
|
47.5
|
83.7
|
21.3
|
44.9
|
Minority
|
44.1**
|
35.0**
|
79.4
|
9.1**
|
26.0‡
|
Marital status*
|
|
|
|
|
|
Unmarried
|
58.9
|
49.8
|
84.5
|
19.6
|
39.5
|
Single
|
55.0
|
45.8
|
83.3
|
20.5
|
44.7
|
Occupational status
|
|
|
|
|
|
Unemployed
|
64.5
|
56.4
|
87.4
|
24.4
|
43.3
|
Employed
|
44.6**
|
34.0**
|
76.3**
|
15.2**
|
44.7
|
Health insurance
|
|
|
|
|
|
Not insured
|
51.3
|
42.0
|
81.8
|
19.3
|
46.0
|
Insured
|
55.9
|
46.7
|
83.6
|
20.4
|
43.7
|
Education
|
|
|
|
|
|
≤ Elementary school
|
54.2
|
45.0
|
82.9
|
16.0
|
35.6
|
Middle school
|
52.9
|
43.8
|
82.9
|
21.2‡
|
48.4**
|
High school
|
60.0§
|
51.6‡
|
86.1
|
27.1**
|
52.5**
|
≥ Collage
|
65.9**
|
54.8‡
|
83.1
|
29.9**
|
54.5**
|
Smoking
|
|
|
|
|
|
Non-smoker
|
58.4
|
50.1
|
85.7
|
21.7
|
43.3
|
Ex-smoker
|
68.4‡
|
55.3
|
80.8
|
28.5§
|
51.6
|
Smoker
|
46.3**
|
36.0**
|
77.8**
|
15.3**
|
42.6
|
Alcohol consumption
|
|
|
|
|
|
Not drinking
|
58.7
|
50.9
|
86.8
|
21.5
|
42.1
|
Drinking
|
50.0**
|
38.1**
|
76.0**
|
18.2§
|
47.9
|
Weight status
|
|
|
|
|
|
Normal weight (BMI<24)
|
50.7
|
40.5
|
79.8
|
20.2
|
50.0
|
Overweight (24≤BMI<28)
|
58.6**
|
49.6**
|
84.8§
|
21.8
|
43.8
|
Obese (BMI≥28)
|
59.4**
|
51.6**
|
83.5‡
|
17.7
|
34.4**
|
¶3,579 adults with hypertension;
Hypertension was defined as having an average systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥ 90 mmHg, self-reported being previously diagnosed as hypertension by a physician or taking antihypertension drugs currently;
Non-smoker was defined as subjects who responded negatively to “have you ever smoked cigarettes?”; ex-smoker was defined as subjects who responded positively to questions “have you ever smoked cigarettes?” but negatively to “do you still smokes cigarettes?”; current smoker was defined as subjects who responded both positive answers to questions “have you ever smoked cigarettes?” and “do you still smokes cigarettes?”; drinking refers to subject who regularly drink alcohol since last year.
Awareness of hypertension status was defined as a self-report of hypertension diagnosed by a doctor before, or taking any antihypertensive drugs;
Control of hypertension was defined as blood pressure (SBP/DBP) < 140/90 mmHg;
a Treatment among subjects who were aware of their hypertension;
b Control among participant who took antihypertension medications;
*Single includes never married, divorced, widowed and separated;
†Western China includes Guangxi, Guizhou and Chongqing; Eastern China includes Shanghai, Beijing, Jiangsu, Liaoning and Shandong; Central China includes Henan, Hubei, Henan and Heilongjiang;
Chi-square test were performed §p<0.05, ‡p<0.01, **p<0.001.
3. Hypertension prevalence, awareness, treatment in CHNS 2001 and InterASIA 2000-2001
Overall, hypertension prevalence in CHNS 2001 was 18.0%. Hypertension awareness, treatment, and control rates were 18.0%, 24.0%, 20.0% and 4.5% among subjects with hypertension in China, respectively. Of these 24.0% individuals who were aware of their condition, 78% were receiving prescribed antihypertensive medications, and 24% of those receiving treatment were adequately controlled. The overall hypertension prevalence was 26.5%, and hypertension awareness, treatment, and control rates were 43.0%, 29.9%, and 7.7%, respectively in InterASIA study. Of those who were aware of their hypertension, 61.5% received treatment, and 29.1% of those who received treatment had their blood pressure controlled (SBP/DBP < 140/90 mmHg). (Table 3) These hypertension rates were lower than those in our study.
Table 3. Comparison of average blood pressure, hypertension prevalence, awareness, treatment and control across China Health and Nutrition Survey (CHNS) 2011, CHNS 2001 and the International Collaborative Study of Cardiovascular Disease in ASIA (InterASIA 2000-2001) among Chinese adults
|
CHNS 2011
|
CHNS 2001(16)
|
InterASiA (2000-2001)(17)
|
Blood pressure‡
|
SBP/DBP
|
SBP/DBP
|
SBP/DBP
|
All subjects
|
143/89
|
N/A
|
149/90
|
Those took treatment
|
143/87
|
N/A
|
148/89
|
Those did not take treatment
|
143/90
|
N/A
|
149/91
|
Hypertension profile (%)
|
|
|
|
Prevalence
|
27.6
|
18.0
|
26.5
|
Awareness
|
55.7
|
24.0
|
43.0
|
Treatment‡
|
46.5
|
20.0
|
29.9
|
Treatment§
|
83.0
|
78%
|
61.5
|
Control‡
|
20.3
|
4.5
|
7.7
|
Control¶
|
43.8
|
24%
|
29.1
|
SBP systolic blood pressure, DPB diastolic blood pressure;
‡among subjects with hypertension;
§among subjects who were aware of their hypertension;
¶among subjects who took antihypertensive medications;
Control of hypertension was defined as SBP/DBP < 140/90 mm Hg among subjects receiving pharmacological treatment;
N/A indicated data not specified.
4. Factors associated with hypertension awareness and treatment
Table 4 presents findings from multivariate logistic regression that identified factors associated with hypertension awareness, treatment, and control. Women were more likely to be aware of their hypertension than men, with an OR of 1.37 (95% CI, 1.12-1.66). Rural residency, minority ethnicity, and unemployment were negatively associated with hypertension awareness. Adults who were overweight and obese were more likely to be aware of their hypertension compared to those with normal weights. Factors associated with treatment of hypertension were similar to those related to hypertension awareness except for smoking status and drinking. Smoking status was not associated with treatment of hypertension. Current drinkers were less likely to be taking antihypertensive medication (OR, 0.53; 95% CI, 0.39-0.72).
Table 4. Multivariable logistic regression analysis of factors associated with hypertension awareness, treatment and control among Chinese adults with hypertension (n=3,579) in CHNS 2011
|
Awareness
|
Treatment¶
|
Control
|
Control‡
|
Women (vs. men)
|
1.37 (1.12 - 1.66)
|
0.94 (0.65 - 1.34)
|
1.32 (1.04 - 1.68)
|
1.17 (0.88 - 1.57)
|
Age group (years)
|
|
|
|
|
18-49 (ref)
|
|
|
|
|
50-64
|
2.34 (1.92 - 2.85)
|
1.87 (1.32 - 2.65)
|
1.87 (1.43 - 2.44)
|
1.33 (0.92 - 1.92)
|
65+
|
3.13 (2.45 - 3.99)
|
2.57 (1.65 - 4.02)
|
1.84 (1.34 - 2.52)
|
1.06 (0.70 - 1.62)
|
Residence
|
|
|
|
|
Urban (vs. rural)
|
1.75 (1.50 - 2.04)
|
1.50 (1.14 - 1.97)
|
2.16 (1.79 - 2.60)
|
1.79 (1.43 - 2.24)
|
Geographic region†
|
|
|
|
|
Central (ref)
|
|
|
|
|
Western
|
0.92 (0.75 - 1.12)
|
1.35 (0.93 - 1.96)
|
1.33 (1.01 - 1.75)
|
1.33 (0.95 - 1.88)
|
Eastern
|
1.50 (1.27 - 1.77)
|
1.52 (1.14 - 2.01)
|
2.12 (1.72 - 2.63)
|
1.78 (1.37 - 2.31)
|
Ethnicity (vs. Han)
|
|
|
|
|
Minority
|
0.74 (0.57 - 0.96)
|
0.78 (0.49 - 1.26)
|
0.47 (0.31 - 0.73)
|
0.52 (0.31 - 0.86)
|
Occupational status (vs. unemployed)
|
|
|
|
|
Employed
|
0.78 (0.66 - 0.93)
|
0.74 (0.54 - 1.00)
|
0.92 (0.74 - 1.15)
|
0.96 (0.72 - 1.26)
|
Marital status* (vs. single)
|
|
|
|
|
Married
|
1.09 (0.89 - 1.34)
|
1.27 (0.89 - 1.83)
|
1.11 (0.87 - 1.43)
|
1.16 (0.86 - 1.57)
|
Health insurance (vs. not insured)
|
|
|
|
|
Insured
|
1.32 (0.93 - 1.87)
|
1.44 (0.77 - 2.68)
|
1.08 (0.70 - 1.66)
|
0.90 (0.52 - 1.55)
|
Weight status
|
|
|
|
|
Normal weight ((BMI<24) (ref)
|
|
|
|
|
Overweight (24≤BMI<28)
|
1.41 (1.20 - 1.66)
|
1.52 (1.15 - 2.01)
|
0.96 (0.79 - 1.16)
|
0.83 (0.65 - 1.05)
|
Obese (BMI≥28)
|
1.57 (1.29 - 1.92)
|
1.99 (1.39 - 2.84)
|
0.77 (0.60 - 0.98)
|
0.56 (0.42 - 0.76)
|
Education
|
|
|
|
|
≤ Elementary school (ref)
|
|
|
|
|
Middle school
|
1.11 (0.92 - 1.33)
|
1.08 (0.78 - 1.50)
|
1.39 (1.11 - 1.74)
|
1.57 (1.20 - 2.06)
|
High school
|
1.34 (1.07 - 1.67)
|
1.42 (0.97 - 2.08)
|
1.65 (1.28 - 2.12)
|
1.53 (1.13 - 2.07)
|
≥ College
|
1.69 (1.23 - 2.32)
|
1.04 (0.64 - 1.71)
|
1.77 (1.26 - 2.48)
|
1.80 (1.20 - 2.70)
|
Smoking status
|
|
|
|
|
Non-smoker (ref)
|
|
|
|
|
Ex-smoker
|
1.62 (1.16 - 2.24)
|
0.75 (0.46 - 1.23)
|
1.47 (1.04 - 2.09)
|
1.23 (0.80 - 1.88)
|
Smoker
|
0.86 (0.70 - 1.04)
|
0.83 (0.59 - 1.18)
|
0.81 (0.63 - 1.05)
|
0.83 (0.61 - 1.14)
|
Alcohol consumption
|
|
|
|
|
Drinking
(vs. not drinking)
|
0.95 (0.79 - 1.13)
|
0.53 (0.39 - 0.72)
|
0.96 (0.77 - 1.19)
|
1.03 (0.78 - 1.35)
|
¶Treatment among subjects who were aware of their hypertension;
‡control among participant who took antihypertension medications;
Hypertension was defined as having an average systolic blood pressure ≥ 140 mmHg, diastolic blood pressure ≥ 90mmHg, self-reported being previously diagnosed as hypertension by a physician or taking antihypertension drugs currently;
Non-smoker was defined as subjects who responded negatively to “have you ever smoked cigarettes?”; ex-smoker was defined as subjects who responded positively to questions “have you ever smoked cigarettes?” but negatively to “do you still smokes cigarettes?”; current smoker was defined as subjects who responded both positive answers to questions “have you ever smoked cigarettes?” and “do you still smokes cigarettes?”; drinking refers to subject who regularly drink alcohol since last year.
Awareness of hypertension status was defined as a self-report of hypertension diagnosed by a Physician before, or taking any antihypertensive drugs;
Control of hypertension was defined as blood pressure (SBP/DBP) < 140/90 mmHg;
*Single includes never married, divorced, widowed and separated;
†Western China includes Guangxi, Guizhou and Chongqing; Eastern China includes Shanghai, Beijing, Jiangsu, Liaoning and Shandong; Central China includes Henan, Hubei, Henan and Heilongjiang.
5. Factors associated with hypertension control
Hypertension was better controlled in women (1.32, 1.04-1.68) compared with men, and in older (≥ 65 years old) (1.84, 1.34-2.52) compared to young or mid-aged adults People in urban areas (2.16; 1.79-2.60) and those from Eastern China (2.12; 1.72-2.63) were more likely to have controlled hypertension. In contrast, minority ethnicity (0.47; 0.31-0.73) and obese (0.77; 0.60-0.98) participants were less likely to have their hypertension controlled. Among participants taking medication for hypertension, those in an urban area, located in Eastern China, and with higher educational attainment had higher odds of hypertension control, whereas minorities (0.52; 0.31-0.86) and people with obesity (0.56; 0.42-0.76) were less likely to have their blood pressure controlled.