Comparison between respondents with and without FM
| FM (n=189) | No FM (n=427) | P value | Weighted P value | |
| Age (years) | 46±11 | 44±12 | 0.312 | 0.04 |
| Female gender, n (%) | 107 (56.6) | 370 (86.7) | <0.0001 | – |
| Marital status | ||||
| Single, n (%) | 37 (19.6) | 79 (18.5) | 0.739 | 1.000 |
| Married, n (%) | 137 (72.5) | 300 (70.3) | 0.631 | 0.519 |
| Separated, n (%) | 12 (6.3) | 39 (9.1) | 0.271 | 0.848 |
| Widowed, n (%) | 3 (1.6) | 9 (2.1) | 1.000 | 1.000 |
| Employment status | ||||
| Student, n (%) | 4 (2.1) | 25 (5.9) | 0.061 | 0.019 |
| Employed, n (%) | 158 (83.6) | 336 (78.7) | 0.188 | 0.047 |
| Unemployed, n (%) | 17 (9.0) | 49 (11.5) | 0.399 | 0.059 |
| Retired, n (%) | 10 (5.3) | 17 (4.0) | 0.523 | 0.187 |
| COVID-19 symptoms | ||||
| Fever, n (%) | 128 (67.7) | 301 (70.5) | 0.491 | 0.746 |
| Cough, n (%) | 100 (52.9) | 192 (45.0) | 0.069 | 0.046 |
| Dyspnoea, n (%) | 86 (45.5) | 151 (35.4) | 0.017 | 0.001 |
| Headache, n (%) | 112 (59.3) | 278 (65.1) | 0.165 | 0.108 |
| Myalgia, n (%) | 133 (70.4) | 303 (71.0) | 0.882 | 0.749 |
| Arthralgia, n (%) | 122 (64.6) | 282 (66.0) | 0.719 | 0.246 |
| Anosmia or ageusia, n (%) | 134 (70.9) | 303 (71.0) | 0.988 | 0.352 |
| Abdominal pain, n (%) | 71 (37.6) | 158 (37.1) | 0.910 | 0.696 |
| Treatment setting | ||||
| No treatment, n (%) | 45 (23.8) | 120 (28.1) | 0.279 | 0.019 |
| Home treatment, n (%) | 103 (54.5) | 272 (63.7) | 0.032 | 0.233 |
| Hospital admission, n (%) | 36 (19.0) | 30 (7.0) | <0.0001 | <0.0001 |
| ICU admission, n (%) | 5 (2.6) | 5 (1.2) | 0.185 | 0.234 |
| COVID-19 duration (days) | 14 (7–21) | 12 (7–20) | 0.424 | 0.820 |
| COVID-19 treatment | ||||
| Analgesics/NSAIDs, n (%) | 131 (69.3) | 291 (68.1) | 0.755 | 0.364 |
| LMWH, n (%) | 58 (30.7) | 73 (17.1) | <0.0001 | <0.0001 |
| Hydroxychloroquine, n (%) | 22 (11.6) | 31 (7.3) | 0.074 | 0.029 |
| Supplemental oxygen, n (%) | 34 (18) | 32 (7.5) | <0.0001 | <0.0001 |
| Pre-existent comorbid diseases | ||||
| Rheumatoid arthritis or other inflammatory arthritides, n (%) | 7 (3.7) | 23 (5.4) | 0.371 | 0.294 |
| Connective tissue diseases, n (%) | 0 (0) | 3 (0.7) | 0.248 | 0.251 |
| Anxiety, n (%) | 37 (19.6) | 71 (16.6) | 0.375 | 0.198 |
| Depression, n (%) | 11 (5.8) | 25 (5.9) | 0.986 | 0.414 |
| Diabetes, n (%) | 3 (1.6) | 7 (1.6) | 0.962 | 0.706 |
| High blood pressure, n (%) | 51 (27) | 46 (10.8) | <0.0001 | <0.0001 |
| Chronic pulmonary diseases, n (%) | 16 (8.5) | 36 (8.4) | 0.989 | 0.575 |
| History of myocardial infarction, n (%) | 1 (0.5) | 2 (0.5) | 0.920 | 0.983 |
| History of stroke, n (%) | 0 (0) | 2 (0.5) | 0.346 | 0.418 |
| Other neurological diseases, n (%) | 1 (0.5) | 2 (0.5) | 0.920 | 0.763 |
| Malignancy, n (%) | 2 (1.1) | 3 (0.7) | 0.650 | 0.349 |
| BMI (kg/m2) | 30.4±4.4 | 23±2.9 | <0.0001 | <0.0001 |
| BMI category | ||||
| Underweight, n (%) | 0 (0) | 19 (4.4) | 0.001 | 0.001 |
| Normal weight, n (%) | 19 (10.1) | 316 (74) | <0.0001 | <0.0001 |
| Overweight, n (%) | 77 (40.7) | 83 (19.4) | <0.0001 | <0.0001 |
| Obese, n (%) | 93 (49.2) | 9 (2.1) | <0.0001 | <0.0001 |
P values <0.05 are highlighted in bold.
BMI, body mass index; FM, fibromyalgia; ICU, intensive care unit; LMWH, low-molecular-weight heparin; NSAID, non-steroidal anti-inflammatory drug.