Table 2.
Risk factors associated with the development of long COVID (WHO definition)
| Risk factor | Total numbers per strata (n = 384,137) | Long COVID symptoms (n = 29,869) (7.78) n (%) | Unadjusted HR (95% CI) | Adjusted HRa (95% CI) |
|---|---|---|---|---|
| Sex | ||||
| Men | 171,593 | 9,090 (5.3) | Ref. | Ref. |
| Women | 212,544 | 20,779 (9. 8) | 1.86 (1.81–1.90) | 1.52 (1.48–1.56) |
| Age (years) | ||||
| 18–29 | 95,969 | 6,932 (7.2) | Ref. | Ref. |
| 30–39 | 78,302 | 5,805 (7.4) | 1.13 (1.10–1.18) | 0.94 (0.90–0.97) |
| 40–49 | 75,349 | 5,784 (7.7) | 1.14 (1.10–1.18) | 0.89 (0.86-0.93) |
| 50–59 | 73,262 | 5,485 (7.5) | 1.07 (1.04–1.11) | 0.80 (0.77–0.83) |
| 60–69 | 35,932 | 2,790 (7.8) | 1.09 (1.05–1.14) | 0.74 (0.70–0.78) |
| ≥70 | 25,323 | 3,073 (12.1) | 1.39 (1.33–1.45) | 0.75 (0.70–0.81) |
| Ethnicity | ||||
| White | 246,717 | 20,462 (8.3) | Ref. | Ref. |
| Asianb | 47,788 | 3,647 (7.6) | 0.90 (0.82–0.99) | 0.99 (0.89–1.09) |
| Black | 15,846 | 1,053 (6.7) | 1.01 (0.91–1.11) | 1.21 (1.10–1.34) |
| Mixed | 5,976 | 407 (6.8) | 0.98 (0.92–1.04) | 1.14 (1.07–1.22) |
| Otherc | 5,438 | 404 (7.4) | 0.94 (0.91–0.97) | 1.06 (1.03–1.10) |
| Missing | 62,372 | 3,896 (6.3) | 0.74 (0.71–0.76) | 0.92 (0.88–0.95) |
| BMI (kg m−2) | ||||
| <18.5 | 10,312 | 762 (7.4) | 0.93 (0.86–1.00) | 0.93 (0.86–1.00) |
| 18.5–25 | 117,630 | 8,849 (7.5) | Ref. | Ref. |
| 25–30 | 109,707 | 8,612 (7.9) | 1.06 (1.03–1.09) | 1.07 (1.04–1.10) |
| >30 | 95,799 | 9,233 (9.6) | 1.29 (1.25–1.33) | 1.10 (1.07–1.14) |
| Missing | 50,689 | 2,413 (4.8) | 0.63 (0.60–0.65) | 0.91 (0.86–0.95) |
| Smoking status | ||||
| Non-smoker | 141,967 | 9,671 (6.8) | Ref. | Ref. |
| Ex-smoker | 139,294 | 12,407 (8.9) | 1.33 (1.29–1.36) | 1.08 (1.05–1.11) |
| Current smoker | 85,765 | 7,072 (8.3) | 1.31 (1.27–1.35) | 1.12 (1.08–1.15) |
| Missing | 17,111 | 719 (4.2) | 0.61 (0.56–0.65) | 0.90 (0.83–0.97) |
| Socioeconomic status quintile (IMD) | ||||
| 1 (least deprived) | 66,564 | 4,392 (6.6) | Ref. | Ref. |
| 2 | 68,657 | 4,963 (7.2) | 1.09 (1.05–1.13) | 1.05 (1.00–1.09) |
| 3 | 70,699 | 5,486 (7.8) | 1.19 (1.14–1.24) | 1.10 (1.05–1.14) |
| 4 | 84,002 | 6,523 (7.8) | 1.20 (1.16–1.25) | 1.07 (1.03–1.11) |
| 5 (most deprived) | 87,270 | 7,883 (9.0) | 1.33 (1.28–1.38) | 1.11 (1.07–1.16) |
| Missing | 6,945 | 622 (9.0) | 1.28 (1.7–1.39) | 1.10 (1.01–1.20) |
| Symptoms recorded before COVID-19 | 78,880 | 13,207 (16.7) | 2.92 (2.85–2.99) | 2.07 (2.02–2.12) |
| Comorbidities | ||||
| COPD | 8,040 | 1,741 (21.7) | 2.71 (2.58–2.85) | 1.55 (1.47–1.64) |
| BPH | 4,961 | 596 (12.0) | 1.39 (1.28–1.51) | 1.39 (1.28–1.52) |
| Fibromyalgia | 4,031 | 900 (22.3) | 3.17 (2.97–3.39) | 1.37 (1.28–1.47) |
| Anxiety | 77,753 | 10,481 (13.5) | 2.17 (2.12–2.23) | 1.35 (1.31–1.39) |
| Erectile dysfunction | 16,678 | 1,551 (9.3) | 1.15 (1.09–1.21) | 1.33 (1.26–1.41) |
| Depression | 83,903 | 11,222 (13.4) | 2.22 (2.17–2.27) | 1.31 (1.27–1.34) |
| Migraine | 43,043 | 5,597 (13.0) | 1.88 (1.83–1.94) | 1.26 (1.22–1.30) |
| Multiple sclerosis | 791 | 98 (12.4) | 1.52 (1.25–1.85) | 1.26 (1.03–1.53) |
| Celiac disease | 1,669 | 207 (12.4) | 1.58 (1.38–1.81) | 1.25 (1.09–1.43) |
| Learning disability | 3,283 | 295 (9.0) | 1.22 (1.09–1.37) | 1.24 (1.11–1.40) |
| IBS | 27,492 | 3,691 (13.4) | 1.84 (1.78–1.91) | 1.20 (1.15–1.24) |
| Endometriosis | 5,727 | 800 (14.0) | 1.92 (1.79–2.06) | 1.19 (1.11–1.28) |
| Low Hb | 20,039 | 2,683 (13.4) | 1.78 (1.71–1.85) | 1.18 (1.13–1.23) |
| Deafness | 3,767 | 514 (13.6) | 1.53 (1.40–1.67) | 1.16 (1.06–1.27) |
| Eating disorder | 3,488 | 504 (14. 5) | 1.92 (1.75–2.09) | 1.16 (1.06–1.27) |
| Substance misuse | 6,449 | 775 (12.0) | 1.69 (1.58–1.82) | 1.15 (1.07–1.23) |
| Back pain | 5,483 | 718 (13.1) | 1.76 (1.64–1.90) | 1.15 (1.07–1.24) |
| Asthma | 76,946 | 8,527 (11.1) | 1.59 (1.55–1.63) | 1.15 (1.12–1.18) |
| Chronic sinusitis | 6,838 | 873 (12.8) | 1.63 (1.52–1.74) | 1.14 (1.07–1.22) |
| PCOS | 9,599 | 1,166 (12.2) | 1.73 (1.63–1.84) | 1.14 (1.07–1.21) |
aaHRs estimated using a multivariable Cox proportional hazards model, including age, sex, ethnic group, socioeconomic status, index year, vaccination status, symptoms recorded before COVID-19 and comorbidities. bThe Asian category consisted of participants with origin from all over Asia including India, Pakistan, China, Cambodia, Thailand, Vietnam, Malaysia, Sri Lanka, Nepal, Bangladesh, Japan or Taiwan. cThe other ethnicity category consisted of patients with native American, Middle Eastern or Polynesian origin.
COPD, chronic obstructive pulmonary disease; BPH, benign prostatic hyperplasia; IBS, irritable bowel syndrome; Hb, hemoglobin; PCOS; polycystic ovary syndrome; Ref., reference.