Table 2. Factors associated with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)-like illness after coronavirus disease 2019 (COVID-19) and ME/CFS-like illness without prior COVID-19 in Kaiser Permanente Northern California, 2022.
| ME/CFS-like illness after COVID-19 among persons with any history of COVID-19 | ME/CFS-like illness without prior COVID-19 among all persons | |||||
|---|---|---|---|---|---|---|
| Factor | n (%)a | PRb (CI) | aPRc (CI) | n (%)a | PRb (CI) | aPRd (CI) |
| Total (n) | 77 | - | - | 569 | - | - |
| Age, years | ||||||
| 18–34 | 9 (0.82) | -e | - | 86 (1.73) | - | - |
| 35–49 | 34 (0.62) | 0.76 (0.14, 4.02) | 0.87 (0.15, 5.09) | 170 (1.27) | 0.73 (0.34, 1.57) | 0.64 (0.29, 1.4) |
| 50–64 | 26 (0.11) | 0.13 (0.03, 0.55) | 0.17 (0.04, 0.75) | 241 (2.19) | 1.26 (0.59, 2.73) | 0.89 (0.4, 1.97) |
| 65+ | 8 (0.04) | 0.05 (0.01, 0.2) | 0.07 (0.02, 0.34) | 72 (0.57) | 0.33 (0.12, 0.91) | 0.15 (0.05, 0.48) |
| Race & ethnicity | ||||||
| Asian | 3 (0.01) | 0.02 (0, 0.08) | 0.02 (0, 0.11) | 34 (0.94) | 0.75 (0.29, 1.9) | 0.7 (0.28, 1.77) |
| Black | 5 (0.32) | 0.59 (0.08, 4.24) | 0.38 (0.04, 3.36) | 29 (2.83) | 2.24 (0.65, 7.72) | 1.23 (0.36, 4.23) |
| Latino/Hispanic | 25 (0.87) | 1.62 (0.28, 9.26) | 0.81 (0.16, 4.12) | 101 (2.24) | 1.77 (0.85, 3.69) | 1.19 (0.49, 2.89) |
| White | 35 (0.54) | - | - | 348 (1.26) | - | - |
| Other/Unknown | 9 (0.11) | 0.2 (0.06, 0.75) | 0.12 (0.03, 0.49) | 57 (1.01) | 0.8 (0.4, 1.61) | 0.57 (0.27, 1.22) |
| Sex | ||||||
| Female | 60 (0.46) | 0.96 (0.17, 5.28) | 0.78 (0.07, 8.59) | 452 (1.83) | 2.08 (0.96, 4.53) | 1.85 (0.81, 4.26) |
| Male | 17 (0.49) | - | - | 117 (0.88) | - | - |
| Charlson Comorbidity Index score | ||||||
| 0 or no visits | 43 (0.59) | - | - | 301 (1.17) | - | - |
| 1–2 | 26 (0.18) | 0.31 (0.08, 1.23) | 0.41 (0.1, 1.72) | 188 (1.83) | 1.56 (0.77, 3.18) | 1.87 (1.02, 3.44) |
| 3+ | 8 (0.09) | 0.16 (0.05, 0.52) | 0.4 (0.09, 1.73) | 80 (2.37) | 2.02 (0.85, 4.79) | 4.53 (1.73, 11.87) |
| Body mass index (kg/m 2 ) | ||||||
| < 30 | 27 (0.28) | - | - | 252 (1.14) | - | - |
| ≥ 30 | 42 (0.67) | 2.44 (0.34, 17.51) | 1.71 (0.28, 10.58) | 272 (2.5) | 2.19 (1.15, 4.17) | 1.65 (0.89, 3.08) |
| COVID-19 vaccination status at time of first COVID-19 episode | ||||||
| None | 53 (2.16) | - | - | - | - | - |
| At least one vaccination | 22 (0.03) | 0.01 (0, 0.04) | 0.02 (0.01, 0.05) | - | - | - |
CI = 95% confidence interval
aUnweighted row count, weighted row percent
bCrude prevalence ratio (CI)
cPrevalence ratio (CI) adjusted for age, race/ethnicity, sex, Charlson Comorbidity Index score, BMI, vaccination status at time of first COVID-19 episode
dPrevalence ratio (CI) adjusted for age, race/ethnicity, sex, Charlson Comorbidity Index score, BMI
eDash indicates the reference group