Table 1.
Descriptive analysis of risk factors according to the residence area (proximal versus reference).
| Variable | Reference Area | Proximal Area | Total | p | |||
|---|---|---|---|---|---|---|---|
| n | % (or mean ± SD) | n | % (or mean ± SD) | n | % (or mean ± SD) | ||
| Gender | 1.000 | ||||||
| Men | 54 | 54.00 | 50 | 54.95 | 104 | 54.45 | |
| Women | 46 | 46.00 | 41 | 45.05 | 87 | 45.55 | |
| Total | 100 | 100.00 | 91 | 100.00 | 191 | 100.00 | |
| Age | 100 | 45.13 ± 15.03 | 91 | 47.31 ± 15.13 | 191 | 46.17 ± 15.08 | 0.320 |
| BMI (categorical) | 0.049 | ||||||
| Normal | 34 | 34.00 | 19 | 20.88 | 53 | 27.75 | |
| Overweight | 42 | 42.00 | 37 | 40.66 | 79 | 41.36 | |
| Obese | 24 | 24.00 | 35 | 38.46 | 59 | 30.89 | |
| Total | 100 | 100.00 | 91 | 100.00 | 191 | 100.00 | |
| BMI (continuous) | 100 | 27.39 ± 4.60 | 91 | 29.16 ± 5.27 | 191 | 28.23 ± 5.00 | 0.014 |
| Pack-years | 98 | 9.43 ± 16.44 | 89 | 8.98 ± 17.84 | 187 | 9.22 ± 17.07 | 0.858 |
| Occupational Exposure | 0.039 | ||||||
| NO | 67 | 67.00 | 47 | 51.65 | 114 | 59.69 | |
| YES | 33 | 33.00 | 44 | 48.35 | 77 | 40.31 | |
| Total | 100 | 100.00 | 91 | 100.00 | 191 | 100.00 | |
| Cardiovascular comorbidity | 0.762 | ||||||
| NO | 67 | 67.00 | 59 | 64.84 | 126 | 65.97 | |
| YES | 33 | 33.00 | 3291 | 35.16 | 65 | 34.03 | |
| Total | 100 | 100.00 | 100.00 | 191 | 100.00 | ||
| Respiratory symptoms in childhood | 0.221 | ||||||
| NO | 82 | 82.00 | 67 | 73.63 | 149 | 78.01 | |
| YES | 18 | 18.00 | 2491 | 26.37 | 42 | 21.99 | |
| Total | 100 | 100.00 | 100.00 | 191 | 100.00 | ||
| Family history of respiratory diseases | 0.008 | ||||||
| NO | 72 | 72.00 | 70 | 76.92 | 142 | 74.35 | |
| YES | 28 | 28.00 | 21 | 23.08 | 49 | 25.65 | |
| Total | 100 | 100.00 | 91 | 100.00 | 191 | 100.00 | |
| Wood heating | 0.008 | ||||||
| NO | 58 | 58.00 | 32 | 35.96 | 90 | 47.62 | |
| YES | 42 | 42.00 | 57 | 64.04 | 99 | 52.38 | |
| Total | 100 | 100.00 | 89 | 100.00 | 189 | 100.00 | |
| Employed | 0.083 | ||||||
| NO | 50 | 50.00 | 34 | 37.36 | 84 | 43.99 | |
| YES | 50 | 50.00 | 57 | 62.64 | 107 | 56.02 | |
| Total | 100 | 100.00 | 91 | 100.00 | 191 | 100.00 | |
| Metabolic comorbidity | 1.000 | ||||||
| NO | 72 | 72.00 | 66 | 72.53 | 138 | 43.98 | |
| YES | 28 | 28.00 | 25 | 27.47 | 53 | 56.02 | |
| Total | 100 | 100.00 | 91 | 100.00 | 191 | 100.00 | |
| Distance from the main road running through the valley (buffer 500 m) | <0.0001 | ||||||
| Near | 4 | 4.00 | 33 | 36.26 | 37 | 19.37 | |
| Far | 96 | 96.00 | 58 | 63.74 | 154 | 80.63 | |
| Total | 100 | 100.00 | 91 | 100.00 | 191 | 100.00 | |
| Employed in Industry | 0.004 | ||||||
| NO | 90 | 90.00 | 67 | 73.63 | 157 | 82.20 | |
| YES | 10 | 10.00 | 24 | 26.37 | 34 | 17.80 | |
| Total | 100 | 100.00 | 91 | 100.00 | 191 | 100.00 | |
Notes—N: number; SD: standard deviation; BMI: body mass index. Acute myocardial infarction or ischemic heart disease, stroke or transient ischemic attack, obliterative arterial disease of the lower limbs, deep vein thrombosis, and embolism were considered as cardiovascular comorbidity. Jaundice, liver disorders or colic, liver failure, hepatitis, high cholesterol and/or triglycerides in the blood, diabetes were considered as metabolic comorbidities.