Table 1.
Characteristics of participants by smoking statusa
| Variables | Nonsmokers (n = 227) | Former smokers (n = 856) | Current smokers (n = 331) | p-value |
|---|---|---|---|---|
| Age (y) | 71.6 ± 0.4 | 72.1 ± 0.2 | 71.3 ± 0.3 | 0.1433 |
| BMI (kg/m2) | 23.6 ± 0.2 | 23.4 ± 0.1 | 22.7 ± 0.2 | 0.0009 |
| AMD | 35 (12.5) | 115 (14.5) | 56 (18.0) | 0.3052 |
| Residential area | ||||
| Urban | 154 (66.0) | 588 (67.5) | 207 (62.3) | 0.3489 |
| Rural | 73 (34.0) | 268 (32.5) | 124 (37.7) | |
| Education | ||||
| Less than high school | 127 (57.3) | 509 (64.0) | 241 (74.9) | 0.0005 |
| High school and above | 99 (42.7) | 347 (36.0) | 90 (25.1) | |
| Family income | ||||
| < 25th | 88 (36.1) | 373 (44.4) | 182 (54.1) | 0.0113 |
| 25th to 50th | 76 (38.2) | 251 (29.9) | 76 (22.7) | |
| 50th to 75th | 38 (16.3) | 129 (13.8) | 40 (13.4) | |
| 75th to 100th | 24 (9.4) | 96 (11.8) | 30 (9.8) | |
| Alcohol consumption | ||||
| Never | 88 (40.2) | 281 (32.1) | 83 (25.1) | 0.0007 |
| ≤ 1 mo | 41 (19.1) | 162 (19.6) | 51 (15.6) | |
| 2–4/mo | 42 (17.6) | 138 (15.1) | 52 (16.0) | |
| 2–3/wk | 35 (14.4) | 124 (14.6) | 56 (16.6) | |
| ≥ 4 wk | 20 (8.7) | 148 (18.7) | 89 (26.7) | |
| Dietary supplement use | ||||
| Yes | 89 (36.1) | 373 (42.2) | 113 (34.4) | 0.0940 |
| Diabetes mellitus | 35 (15.0) | 162 (18.2) | 68 (19.3) | 0.5096 |
| Hypertension | 98 (42.2) | 438 (52.4) | 129 (40.2) | 0.0028 |
| Smoking behavior | ||||
| Daily smoking amount of former smokers (n/d) | – | 29.8 ± 1.2 | – | – |
| Duration of former smoking (y) | – | 18.3 ± 0.5 | – | – |
| Daily smoking amount of current smokers (n/d) | – | – | 13.8 ± 0.5 | – |
| Duration of smoking (y) | – | – | 49.5 ± 0.5 | – |
Data availability was limited in the following categories: age (n = 1414); BMI (n = 1414); residential area (n = 1414); education (n = 1413); family income (n = 1403); alcohol consumption (n = 1410); dietary supplement use (n = 1414); diabetes mellitus (n = 1414); hypertension (n = 1414); daily smoking amount of former smokers (n = 852); duration of former smoking (n = 855); daily smoking amount (n = 331); duration of smoking (n = 331)
BMI body mass index, AMD age related macular degeneration
aValues are mean ± s.e. or n (%); n = 1414