Table 1.
Baseline characteristics at baseline by group
| Variable | No (%) | ||
| Oral route (n=140) | IM route (n=143) | Total (n=283) | |
| Sociodemographic data | |||
| Women | 87 (62.1) | 78 (54.5) | 165 (58.3) |
| Age (years), mean (SD) | 74.2 (5.8) | 76.2 (6.7) | 75.2 (6.3) |
| Educational level | |||
| Illiteracy | 4 (2.9) | 7 (5.1) | 11 (4.0) |
| Incomplete education | 48 (34.5) | 46 (33.6) | 94 (34.1) |
| Primary education | 58 (41.7) | 63 (46.0) | 121 (43.8) |
| Secondary education | 16 (11.5) | 10 (7.3) | 26 (9.4) |
| Tertiary education | 4 (2.9) | 4 (2.9) | 8 (2.9) |
| Higher education | 9 (6.5) | 7 (5.1) | 16 (5.8) |
| Social occupational class* | |||
| Classes I–IV | 31 (27.7) | 33 (27.3) | 64 (27.5) |
| Classes V–VI | 81 (72.3) | 88 (72.7) | 169 (72.5) |
| Living alone | 32 (21.4) | 30 (22.2) | 62 (21.9) |
| Clinical data | |||
| Tobacco habit | |||
| Ex-smoker | 27 (19.7) | 25 (18.4) | 52 (19.0) |
| Smoker | 9 (6.6) | 10 (7.4) | 19 (7.0) |
| Non-smoker | 101 (73.7) | 101 (74.3) | 202 (74.0) |
| Vegetarian | 2 (1.4) | 0 (0) | 2 (0.7) |
| Having undergone gastrectomy | 1 (0.7) | 2 (1.4) | 3 (1.1) |
| Symptoms | |||
| Paresthesia | 33 (23.6) | 45 (31.5) | 78 (27.6) |
| Asthenia | 43 (30.7) | 54 (37.8) | 97 (34.3) |
| Loss of appetite | 12 (8.6) | 30 (21.0) | 42 (14.8) |
| Sadness | 37 (26.4) | 53 (37.1) | 90 (31.8) |
| Showing ≥1 symptom | 70 (50.0) | 83 (58.0) | 153 (54.1) |
| Signs | |||
| Glossitis | 2 (1.4) | 9 (6.3) | 11 (3.9) |
| Position sensitivity | 2 (1.4) | 1 (0.7) | 3 (1.1) |
| Vibration sensitivity | 15 (10.7) | 13 (9.1) | 28 (9.9) |
| Showing ≥1 altered sign | 16 (11.4) | 21 (14.7) | 37 (13.1) |
| Haemogram-clinical biochemistry | |||
| Vitamin B12 (pg/mL), mean (SD) | 173.1 (27.3) | 166.4 (32.6) | 169.7 (30.2) |
| Anaemia† | 16 (11.4) | 27 (18.9) | 43 (15.2) |
| Haematocrit (%), mean (SD) | 42.4 (4.0) | 41.9 (4.2) | 42.1 (4.1) |
| MCV (fL), mean (SD) | 92.1 (6.7) | 94.3 (7.4) | 93.2 (7.1) |
| Anti-intrinsic factor antibody | 15 (11.0) | 15 (10.5) | 30 (10.8) |
| Medication | |||
| Proton-pump inhibitors (PPI) | 57 (40.7) | 64 (44.8) | 121 (42.8) |
| Metformin | 69 (49.3) | 56 (39.2) | 125 (44.2) |
| PPI and metformin | 33 (23.6) | 30 (21.0) | 63 (22.3) |
| Scales | |||
| MMSE‡, mean (SD) | 30.8 (4.6) | 30.2 (4.8) | 30.5 (4.7) |
| EQ-5D-utilities, mean (SD) | 0.817 (0.169) | 0.855 (0.139) | 0.836 (0.171) |
*Neoweberian occupational social class (CSO-SEE12).41
†Anaemia was defined by the WHO criteria (haemoglobin <12 g/L in women and <13 g/L in men). https://www.who.int/vmnis/indicators/haemoglobin.
‡Maximum score=35 points. Normal score=30–35. Borderline score=24–29 points. Scores <24 points in patients aged >65 years and scores <29 points in patients aged <65 years suggest cognitive impairment.
IM, intramuscular; MCV, Mean Corpuscular Volume; MMSE, Mini Mental State Examination.