Table 3.
Immunogenicity after 6 months of vaccination, and associated factors
| Total [n = 126] |
Serology after 6 months | |||
|---|---|---|---|---|
| Positive [120 (95.2%)] |
Negative 6 (4.8%) |
p-Value | ||
| Age, years | 87.62 ± 8.27 | 87.24 ± 8.25 | 95.12 ± 3.97 | 0.03 |
| Females [n (%)] | 104 (82.5) | 98 (81.6) | 6 (100) | 0.2 |
| Charlson Index > 3 [n (%)] | 81 (64.3) | 77 (64.1) | 4 (66.6) | 0.7 |
| Number of drugs | 7.86 ± 3.31 | 7.76 ± 3.33 | 7.82 ± 2.31 | 0.9 |
| MNA-Short 8–11 points [n (%)] | 8 (6.3) | 8 (6.6) | 0 (0) | 0.5 |
| IB [n (%)] | ||||
| Moderate (IB = 40–59) | 29 (23) | 27 (22.5) | 2 (33.3) | 0.6 |
| Grave (IB = 20–39) | 28 (22.2) | 28 (23.3) | 0 (0) | |
| Total (IB = 0–19) | 30 (23.8) | 29 (24.2) | 1 (16.7) | |
| Dementia [n (%)] | 110 (87.3) | 104 (86.6) | 6 (100) | 0.3 |
| Reisberg GDS [n (%)] | ||||
| Moderate (GDS 5) | 12 (9.5) | 12 (10) | 0 (0) | 0.1 |
| Grave (GDS 6–7) | 72 (57.1) | 69 (57.5) | 3 (50) | |
| CFS [n (%)] | ||||
| Mild–moderate (CFS = 5–6) | 56 (44.4) | 51 (83.3) | 5 (83.3) | 0.9 |
| Severe (CFS = 7–9) | 67 (53.2) | 66 (55) | 1 (16.7) | |
| FI-VIG | ||||
| Need for palliative care (IF-VIG > 0.06) [n (%)] | 9 (7.1) | 8 (6.6) | 1 (16.6) | 0.2 |
| Handgrip strength | ||||
| Right | 10.75 ± 6.83 | 10.63 ± 6.95 | 10.87 ± 3.12 | 0.1 |
| Left | 10.34 ± 6.71 | 10.66 ± 6.80 | 10.04 ± 3.10 | 0.09 |
| Previous COVID-19 [n (%)] | 88 (69.8) | 87 (70) | 1 (16.6) | 0.009 |
| Serology + prior vaccination [n (%)] | 76 (60.31) | 76 (63.3) | 0 (0) | 0.02 |
Statistically significant values are given in bold
In multivariate analysis using a linear regression model (enter), no particular variable was associated with the presence of serology after 6 months: older age (years of age: B = 0.812, 95% CI 0.608–1.084; p = 0.157), sex (male sex: B = 0.241, 95% CI 0.098–1.981; p = 0.998), comorbidity (Charlson Index: B = 0.909, 95% CI 0.505–1.638; p = 0.909), disability (Barthel Index: B = 0.958, 95% CI 0.907–1.013; p = 0.130), frailty (SCF: B = 0.398, 95% CI 0.045–3.481; p = 0.291), previous Covid-19 (B = 0.782, 95% CI 0.048–12.859; p = 0.996), and positive serology prior to vaccination (B = 0.112, 95% CI 0.167–1.076; p = 0.996)
IB Barthel Index, GDS Global Deterioration Scale, CFS Clinical Frail Scale, FI-VIG Frailty Index-VIG, COVID-19 coronavirus disease 2019, CI confidence interval