Table 3: Prevalence ratios for hypertension, by location, BMI and smoking status* .
| Variable | No. of patients |
Unadjusted prevalence ratio | Adjusted prevalence ratio† (95% CI) | ||
|---|---|---|---|---|---|
| All | With hypertension | Without hypertension | |||
| Location |
|||||
| Urban |
188 076 |
42 448 |
146 628 |
1.00 |
1.00 (ref) |
| Rural |
54 403 |
14 494 |
39 909 |
1.21 |
1.24 (1.19–1.30) |
| Missing data |
7 867 |
1 238 |
6 629 |
0.71 |
0.95 (0.82–1.11) |
| BMI |
|||||
| 18–24 (normal) |
52 989 |
11 286 |
41 703 |
1.00 |
1.00 (ref) |
| < 18 (underweight) |
7 745 |
1 795 |
5 950 |
1.09 |
1.13 (0.95–1.35) |
| 25–29 (overweight) |
51 433 |
13 769 |
37 664 |
1.26 |
1.51 (1.38–1.64) |
| ≥ 30 (obese) |
47 510 |
14 785 |
32 725 |
1.46 |
2.42 (2.22–2.63) |
| Missing data |
90 669 |
15 545 |
75 124 |
0.81 |
0.99 (0.91–1.08) |
| Smoking status |
|||||
| Never smoked |
62 020 |
14 284 |
47 736 |
1.00 |
1.00 (ref) |
| Current smoker |
17 629 |
3 679 |
13 308 |
0.91 |
1.01 (0.89–1.15) |
| Past smoker |
20 024 |
6 716 |
13 308 |
1.46 |
1.94 (1.73–2.16) |
| Missing data | 150 673 | 32 501 | 118 172 | 0.94 | 1.50 (1.40–1.61) |
Note: CI = confidence interval, ref = reference category. *Missing data included as a group in the models. Because of the large amount of missing data, especially for BMI and smoking status, we included people with missing data as a group in each variable when calculating prevalence ratios. †Log-binomial regression. Along with 5 main effect variables (age, sex, location, BMI and smoking status), the model also included 8 interaction terms: age*sex, age*BMI, sex*BMI, age*smoking, sex*smoking, location*BMI, location*smoking, and BMI*smoking. Only the effects of location, BMI and smoking status are reported in this table.