Table 3.
Incidence density and RA cohort to non-RA cohort HRs of hearing loss by sex, age and comorbidity in the two cohorts
| Variables | Non-RA cohort | RA cohort | RA cohort to non-RA cohort | |||||
| HR (95% CI) | ||||||||
| Event (n) | Person-years | Incidence density† | Event (n) | Person-years | Incidence density† | Crude | Adjusted‡ | |
| Sex | ||||||||
| Women | 663 | 454 249 | 1.46 | 314 | 110 956 | 2.83 | 1.94 (1.69 to 2.22)*** | 1.95 (1.70 to 2.23)*** |
| Men | 264 | 117 782 | 2.24 | 115 | 28 130 | 4.09 | 1.82 (1.46 to 2.27)*** | 1.85 (1.48 to 2.30)*** |
| Age, years | ||||||||
| 20–39 | 40 | 98 817 | 0.40 | 19 | 25 020 | 0.76 | 1.89 (1.09 to 3.26)* | 1.80 (1.02 to 3.16)* |
| 40–59 | 355 | 295 193 | 1.20 | 208 | 72 982 | 2.85 | 2.37 (2.00 to 2.81)*** | 2.32 (1.95 to 2.76)*** |
| ≥60 | 532 | 178 021 | 2.99 | 202 | 41 084 | 4.92 | 1.63 (1.39 to 1.92)*** | 1.62 (1.37 to 1.90)*** |
| Comorbidity | ||||||||
| DM | ||||||||
| No | 765 | 514 262 | 1.49 | 362 | 124 722 | 2.90 | 1.95 (1.72 to 2.21)*** | 1.94 (1.71 to 2.20)*** |
| Yes | 162 | 57 770 | 2.80 | 67 | 14 363 | 4.66 | 1.66 (1.25 to 2.21)*** | 1.74 (1.30 to 2.32)*** |
| Hyperlipidaemia | ||||||||
| No | 654 | 464 753 | 1.41 | 320 | 113 890 | 2.81 | 2.00 (1.75 to 2.28)*** | 1.96 (1.72 to 2.25)*** |
| Yes | 273 | 107 279 | 2.54 | 109 | 25 195 | 4.33 | 1.69 (1.36 to 2.11)*** | 1.74 (1.39 to 2.18)*** |
| Hypertension | ||||||||
| No | 481 | 402 716 | 1.19 | 233 | 97 031 | 2.40 | 2.01 (1.72 to 2.35)*** | 1.94 (1.66 to 2.28)*** |
| Yes | 446 | 169 316 | 2.63 | 196 | 42 054 | 4.66 | 1.76 (1.49 to 2.08)*** | 1.82 (1.54 to 2.16)*** |
| Hyperthyroidism | ||||||||
| No | 909 | 563 891 | 1.61 | 416 | 135 733 | 3.06 | 1.90 (1.69 to 2.13)*** | 1.92 (1.71 to 2.16)*** |
| Yes | 18 | 8140 | 2.21 | 13 | 3352 | 3.88 | 1.76 (0.86 to 3.58) | 1.72 (0.84 to 3.55) |
| IHD | ||||||||
| No | 671 | 491 566 | 1.37 | 316 | 118 909 | 2.66 | 1.95 (1.70 to 2.23)*** | 1.96 (1.71 to 2.24)*** |
| Yes | 256 | 80 466 | 3.18 | 113 | 20 176 | 5.60 | 1.75 (1.40 to 2.18)*** | 1.75 (1.40 to 2.19)*** |
| Stroke | ||||||||
| No | 896 | 559 458 | 1.60 | 414 | 136 197 | 3.04 | 1.90 (1.69 to 2.13)*** | 1.90 (1.69 to 2.14)*** |
| Yes | 31 | 12 573 | 2.47 | 15 | 2888 | 5.19 | 2.10 (1.13 to 3.89)* | 2.18 (1.16 to 4.12)* |
| CKD | ||||||||
| No | 835 | 538 065 | 1.55 | 369 | 124 534 | 2.96 | 1.91 (1.69 to 2.16)*** | 1.94 (1.71 to 2.19)*** |
| Yes | 92 | 33 967 | 2.71 | 60 | 14 551 | 4.12 | 1.53 (1.11 to 2.12)* | 1.73 (1.25 to 2.42)** |
| Hypothyroidism | ||||||||
| No | 917 | 569 055 | 1.61 | 426 | 137 393 | 3.10 | 1.92 (1.71 to 2.16)*** | 1.94 (1.73 to 2.18)*** |
| Yes | 10 | 2977 | 3.36 | 3 | 1692 | 1.77 | 0.53 (0.15 to 1.93) | 0.69 (0.19 to 2.57) |
| Autoimmune diseases§ | ||||||||
| No | 916 | 568 956 | 1.61 | 418 | 135 186 | 3.09 | 1.92 (1.71 to 2.15)*** | 1.94 (1.73 to 2.18)*** |
| Yes | 11 | 3076 | 3.58 | 11 | 3899 | 2.82 | 0.79 (0.34 to 1.82) | 0.89 (0.38 to 2.07) |
*P<0.05, **P<0.01, ***P<0.001.
†Per 1000 person-years.
‡Model mutually adjusted for sex, age (continuous), DM, hyperlipidaemia, hypertension, hyperthyroidism, IHD, stroke, CKD, hypothyroidism and autoimmune diseases.
§Autoimmune diseases including psoriasis, SLE, systemic sclerosis, Sjogren syndrome, dermatomyositis, polymyositis and vasculitis.
CKD, chronic kidney disease; DM, diabetes mellitus; IHD, ischaemic heart disease; RA, rheumatoid arthritis; SLE, systemic lupus erythematosus.