Table 4 Frequency of breathing irregularities by age group and mutation type
| Â | Breath-holding | Hyperventilation | ||||||
|---|---|---|---|---|---|---|---|---|
| Â | Not at all | Less than everyday | Every day or many times a day | Total | Not at all | Less than everyday | Every day or many times a day | Total |
n (%a) | 118 (31.2) | 79 (20.9) | 181 (47.9) | 378 | 207 (53.6) | 77 (20.0) | 102 (26.4) | 386 |
Age group, n (%a) | ||||||||
 0–6 years | 17 (34.7) | 8 (16.3) | 24 (49.0) | 49 | 19 (39.6) | 5 (10.4) | 24 (50.0) | 48 |
 7–12 years | 31 (23.9) | 30 (23.1) | 69 (53.1) | 130 | 71 (54.6) | 19 (14.6) | 40 (30.8) | 130 |
 13–19 years | 37 (32.7) | 16 (14.2) | 60 (53.1) | 113 | 66 (57.9) | 26 (22.8) | 22 (19.3) | 114 |
 20 years and above | 33 (38.4) | 25 (29.1) | 28 (32.6) | 86 | 51 (54.3) | 27 (28.7) | 16 (17.0) | 94 |
Mutation type, n (%a) | ||||||||
 C-terminal deletion | 13 (31.7) | 7 (17.1) | 21 (51.2) | 41 | 25 (59.5) | 4 (9.5) | 13 (31.0) | 42 |
 Early truncating | 5 (17.9) | 6 (21.4) | 17 (60.7) | 28 | 14 (51.9) | 4 (14.8) | 9 (33.3) | 27 |
 Large deletion | 5 (19.2) | 7 (26.9) | 14 (53.9) | 26 | 14 (53.8) | 6 (23.1) | 6 (23.1) | 26 |
 p.Arg106Trp | 5 (33.3) | 5 (33.3) | 5 (33.3) | 15 | 8 (53.3) | 4 (26.7) | 3 (20.0) | 15 |
 p.Arg133Cys | 10 (34.5) | 6 (20.7) | 13 (44.8) | 29 | 15 (50.0) | 7 (23.3) | 8 (26.7) | 30 |
 p.Arg168* | 14 (35.0) | 10 (25.0) | 16 (40.0) | 40 | 24 (55.8) | 11 (25.6) | 8 (18.6) | 43 |
 p.Arg255* | 12 (27.3) | 5 (11.4) | 27 (61.4) | 44 | 22 (50.0) | 7 (15.9) | 15 (34.1) | 44 |
 p.Arg270* | 7 (29.2) | 7 (29.2) | 10 (41.6) | 24 | 13 (54.2) | 4 (16.6) | 7 (29.2) | 24 |
 p.Arg294* | 9 (33.3) | 5 (18.5) | 13 (48.2) | 27 | 15 (55.6) | 2 (7.4) | 10 (37.0) | 27 |
 p.Arg306Cys | 8 (30.8) | 5 (19.2) | 13 (50.0) | 26 | 11 (42.3) | 5 (19.2) | 10 (38.5) | 26 |
 p.Thr158Met | 10 (29.4) | 7 (20.6) | 17 (50.0) | 34 | 18 (50.0) | 9 (25.0) | 9 (25.0) | 36 |
 Other | 20 (45.5) | 9 (20.5) | 15 (34.1) | 44 | 28 (60.9) | 14 (30.4) | 4 (8.7) | 46 |