Table 1
Descriptive characteristics of southern Chilean shellfish divers. Total absolute and relative frequencies as well as stratified for sampling frame.
| Characteristics | Total N = 125 | Divers on list of fishermen’s unions N = 98 | Divers not belonging to a union N = 27 | PChi2 |
|---|---|---|---|---|
| n (%) | n (%) | n (%) | ||
| Age (years) ≥ 40 | 93 (74.4) | 75 (76.5) | 18 (66.7) | 0.29 |
| Secondary education | 45 (36.0) | 34 (34.7) | 11 (40.7) | 0.56 |
| Active smoker | 54 (43.5) | 43 (44.3) | 11 (40.7) | 0.74 |
| Alcohol consumption | 91 (72.8) | 70 (71.4) | 21 (77.8) | 0.51 |
| Alcoholism | 60 (48.0) | 46 (46.9) | 14 (51.9) | 0.65 |
| Diving years (median with range) | 25 (minimum: 1.0; maximum: 52.0) | 25 (minimum: 1.0; maximum: 52.0) | 25 (minimum: 1.0; maximum: 34.0) | (pMann-Whitney-U-test) 0.21 |
| Dives per week | 0.95 | |||
| <or equal to seven dives | 84 (67.2) | 66 (67.3) | 18 (66.7) | |
| More than seven dives | 41 (32.8) | 32 (32.7) | 9 (33.3) | |
| Diving duration | 0.56 | |||
| <or equal 60 minutes | 43 (34.4) | 35 (35.7) | 8 (29.6) | |
| More than 60 minutes | 82 (65.6) | 63 (64.3) | 19 (70.4) | |
| Ability to read decompression tables | 60 (48.0) | 47 (48.0) | 13 (48.1) | 0.99 |
| Use of decompression tables | 0.73 | |||
| Occasionally | 44 (35.2) | 34 (34.7) | 10 (37.0) | |
| Always | 54 (43.2) | 44 (44.9) | 10 (37.0) | |
| Deep dives | 98 (78.4) | 79 (80.6) | 19 (70.4) | 0.25 |
| Middle ear barotrauma (NMissing 3) | 28 (23.0) | 25 (26.3) | 3 (11.1) | (pFisher exact) 0.08 |
| Decompression sickness## | 100 (80.0) | 82 (83.7) | 18 (66.7) | 0.05 |
| Audiometry | 0.63 | |||
| -Normal | 57 (45.6) | 43 (43.9) | 14 (51.9) | |
| -Suggestive of sensorineural hearing loss | 36 (28.8) | 30 (30.6) | 6 (22.2) | |
| -Others (Suggestive of conductive hearing loss, unilateral hearing loss and mixed hearing loss) | 32 (25.6) | 25 (25.5) | 7 (25.9) |
[i] ##Symptoms of type II decompression sickness more than once.
Table 2
Prevalence of hearing loss in southern Chilean shellfish divers by potential risk factors.
| Any type of hearing loss | Sensorineural hearing loss | Other types of hearing loss | |||||||
|---|---|---|---|---|---|---|---|---|---|
| n (%) | NMissing | pChi2 | n (%) | NMissing | pChi2 | n (%) | NMissing | pChi2 | |
| Age (years) | <0.01 | <0.01# | <0.01# | ||||||
| <40 | 5 (15.6) | 2 (6.90) | 3 (10.0) | ||||||
| ≥40 | 63 (76.7) | 34 (53.1) | 29 (49.2) | ||||||
| Secondary education | 0.02 | 0.06 | 0.04 | ||||||
| No | 50 (62.5) | 26 (46.4) | 24 (44.4) | ||||||
| Yes | 18 (40.0) | 10 (27.0) | 8 (22.9) | ||||||
| Active smokers | 1 | 0.02 | 0.01 | 1 | 0.26 | ||||
| No | 44 (62.9) | 26 (50.0) | 18 (4.9) | ||||||
| Yes | 23 (42.6) | 10 (24.4) | 13 (29.5) | ||||||
| Regular alcohol consumption | 0.54 | 0.73 | 0.50 | ||||||
| No | 20 (58.8) | 10 (41.7) | 10 (41.7) | ||||||
| Yes | 48 (52.7) | 26 (37.7) | 22 (33.8) | ||||||
| Alcoholism | 0.34 | 0.20 | 0.81 | ||||||
| No | 38 (58.5) | 22 (44.9) | 16 (37.2) | ||||||
| Yes | 30 (50.0) | 14 (31.8) | 16 (34.8) | ||||||
| Diving years | <0.01 | <0.01 | <0.01 | ||||||
| ≤25 | 22 (31.9) | 9 (16.1) | 13 (21.7) | ||||||
| >25 | 46 (82.1) | 27 (73.0) | 19 (65.5) | ||||||
| Nº of dives per week | 0.52 | 0.24 | 0.87 | ||||||
| ≤7 | 44 (52.4) | 21 (34.4) | 23 (36.5) | ||||||
| >7 | 24 (58.5) | 15 (46.9) | 9 (34.6) | ||||||
| Diving duration | 0.82 | 0.59 | 0.84 | ||||||
| ≤1 hour/dive | 24 (55.8) | 14 (42.2) | 10 (34.5) | ||||||
| >1 hour/dive | 44 (53.7) | 22 (36.7) | 22 (36.7) | ||||||
| Deep dives more than 30 meters | 0.11 | 0.21 | 0.18 | ||||||
| No | 11 (40.7) | 6 (27.3) | 5 (23.8) | ||||||
| Yes | 57 (58.2) | 30 (42.3) | 27 (39.7) | ||||||
| Ability to read decompression tables | 0.04 | 0.31 | 0.02 | ||||||
| No | 41 (63.1) | 19 (44.2) | 22 (47.8) | ||||||
| Yes | 27 (45.0) | 17 (34.0) | 10 (23.3) | ||||||
| Use of decompression tables | 0.54 | 0.46 | 0.81 | ||||||
| Never | 16 (59.3) | 9 (45.0) | 7 (38.9) | ||||||
| Occasionally | 24 (54.5) | 13 (39.4) | 11 (35.5) | ||||||
| Always | 28 (51.9) | 14 (35.0) | 14 (35.0) | ||||||
| Middle ear barotrauma | 3 | 0.42 | 3 | 0.66 | 1 | 0.36 | |||
| No | 49 (52.1) | 26 (36.6) | 23 (33.8) | ||||||
| Yes | 17 (60.7) | 8 (42.1) | 9 (45.0) | ||||||
| Decompression sickness## | 0.11 | 0.06# | 0.42 | ||||||
| No | 10 (40.0) | 4 (21.1) | 6 (28.6) | ||||||
| Yes | 58 (58.8) | 32 (43.2) | 26 (38.2) | ||||||
[i] #: pFisher Exact.
##Symptoms of type II decompression sickness more than once.
Table 3
Crude (cOR) and adjusted (aOR) odds ratio for different types of hearing loss among shellfish divers in southern Chile.
| Variables | Any type of hearing loss | Sensorineural hearing loss | Other type of hearing loss | |||
|---|---|---|---|---|---|---|
| cOR 95% CI | aOR 95% CI | cOR 95% CI | aOR 95% CI | cOR 95% CI | aOR 95% CI | |
| Age (years) ≥ 40 | 11.3 (4.0–32.4) | 5.4 (1.5–19.1) | 15.3 (3.4–69.8) | 4.4 (0.8–25.1) | 8.7 (2.4–31.8) | 6.1 (1.1–32.0) |
| <40 | 1 | 1 | 1 | 1 | 1 | 1 |
| Secondary education: Yes | 0.40 (0.2–0.9) | 0.9 (0.3–2.5) | 0.43 (0.2–1.1) | 0.9 (0.2–3.2) | 0.4 (0.1–1.0) | 0.75 (0.2–2.7) |
| No | 1 | 1 | 1 | 1 | 1 | 1 |
| Active smoker | 0.44 (0.2–0.9) | 0.5 (0.2–1.2) | 0.32 (0.1–0.8) | 0.34 (0.1–1.0) | 0.61 (0.3–1.5) | 0.64 (0.2–1.8) |
| Non-smoker | 1 | 1 | 1 | 1 | 1 | 1 |
| Diving years > 25 | 9.83 (4.2–23.0) | 5.41 (2.0–14.7) | 14.1 (5.1–39.0) | 9.20 (2.6–32.6) | 6.90 (2.6–18.3) | 3.7 (1.2–11.7) |
| Diving years ≤ 25 | 1 | 1 | 1 | 1 | 1 | 1 |
| Ability to read decompression tables: Yes | 0.50 (0.2–1.0) | 0.83 (0.3–2.2) | 0.70 (0.3–1.5) | 1.38 (0.4–4.6) | 0.33 (0.1–0.8) | 0.62 (0.2–2.0) |
| No | 1 | 1 | 1 | 1 | 1 | 1 |
| Decompression sickness#: Yes | 2.1 (0.9–5.1) | 0.71 (0.2–2.4) | 2.9 (0.9–9.4) | 0.68 (0.1–3.3) | 1.55 (0.5–4.5) | 0.53 (0.1–2.2) |
| No | 1 | 1 | 1 | 1 | 1 | 1 |
[i] #Symptoms of type II decompression sickness more than once.