Table I.
Characteristics of Participants in Surveys of 1991, 1999, and 2007
| 1991 (n=38,146) | 1999 (n=25,532) | 2007 (n=21,693) | P for Trend | |
|---|---|---|---|---|
| Age, y | 46.7±15.8 | 43.8±13.8 | 52.9±12.0 | <.0001 |
| Sex | <.0001 | |||
| Men | 18,495 (48.5) | 12,354 (48.4) | 8385 (38.7) | |
| Women | 19,651 (51.5) | 13,178 (51.6) | 13,308 (61.3) | |
| Systolic blood pressure | 119.7±19.2 | 124.9±14.9 | 140.1±23.3 | <.0001 |
| Diastolic blood pressure | 73.8±11.1 | 79.0±8.9 | 84.5±12.4 | <.0001 |
| Family history of hypertension | 6783 (17.8) | 5840 (22.9) | 2356 (10.9) | <.0001 |
| Body mass index | 22.5±3.3 | 23.4±2.6 | 24.7±3.7 | <.0001 |
| Underweight | 2892 (7.6) | 517 (2.0) | 702 (3.2) | <.0001 |
| Normal weight | 24,560 (64.4) | 15,383 (60.2) | 9016 (41.6) | |
| Overweight | 8405 (22.0) | 8387 (32.8) | 8187 (37.7) | |
| Obesity | 2289 (6.0) | 1245 (4.9) | 3788 (17.5) | |
| Cigarette smoking | 12,177 (31.9) | 6799 (26.6) | 3744 (17.3) | <.0001 |
| Men | 11,034 (59.7) | 6300 (51.0) | 3555 (42.4) | |
| Women | 1143 (5.8) | 499 (3.8) | 189 (1.4) | |
| Alcohol consumption | 7762 (20.3) | 5367 (21.0) | 3674 (16.9) | <.0001 |
| Men | 7535 (40.7) | 5155 (41.7) | 3564 (42.5) | |
| Women | 227 (1.2) | 212 (1.6) | 110 (0.8) | |
| Education | <.0001 | |||
| Illiterate | 9116 (23.9) | 2521 (9.9) | 4567 (21.1) | |
| Primary school | 7410 (19.4) | 9499 (37.2) | 8375 (38.6) | |
| Middle school | 11,947 (31.3) | 12,540 (49.1) | 6967 (32.1) | |
| High school | 7632 (20.0) | 946 (3.7) | 1380 (6.4) | |
| College/university or above | 2041 (5.4) | 26 (0.1) | 404 (1.9) |
The values are expressed as mean±standard deviation or number (percentage).