Previous SARS-CoV-2 Infection, Age, and Frailty Are Associated With 6-Month Vaccine-Induced Anti-Spike Antibody Titer in Nursing Home Residents.

OBJECTIVES: Older nursing home residents make up the population at greatest risk of morbidity and mortality from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. No studies have examined the determinants of long-term antibody responses post vaccination in this group. DESIGN: Longitudinal cohort study. SETTING AND PARTICIPANTS: Residents from 5 nursing homes assessed before vaccination, and 5 weeks and 6 months post vaccination, with the BNT162b2 messenger RNA SARS-CoV-2 vaccine. METHODS: Comprehensive clinical assessment was performed, including assessment for comorbidity, frailty, and SARS-CoV-2 infection history. Serum nucleocapsid and anti-spike receptor binding domain (RBD) antibodies were analyzed at all timepoints. An in vitro angiotensin-converting enzyme (ACE2) receptor-spike RBD neutralization assay assessed serum neutralization capacity. RESULTS: Of 86 participants (81.1 ± 10.8 years; 65% female), just under half (45.4%; 39 of 86) had evidence of previous SARS-CoV-2 infection. All participants demonstrated a significant antibody response to vaccination at 5 weeks and a significant decline in this response by 6 months. SARS-CoV-2 infection history was the strongest predictor of antibody titer (log-transformed) at both 5 weeks [ß: 3.00; 95% confidence interval (CI): 2.32-3.70; P < .001] and 6 months (ß: 3.59; 95% CI: 2.89-4.28; P < .001). Independent of SARS-CoV-2 infection history, both age in years (ß: -0.05; 95% CI: -0.08 to -0.02; P < .001) and frailty (ß: -0.22; 95% CI: -0.33 to -0.11; P < .001) were associated with a significantly lower antibody titer at 6 months. Anti-spike antibody titers at both 5 weeks and 6 months significantly correlated with in vitro neutralization capacity. CONCLUSIONS AND IMPLICATIONS: In older nursing home residents, SARS-CoV-2 infection history was the strongest predictor of anti-spike antibody titers at 6 months, whereas age and frailty were independently associated with lower titers at 6 months. Antibody titers significantly correlated with in vitro neutralization capacity. Although older SARS-CoV-2 naïve nursing home residents may be particularly vulnerable to breakthrough SARS-CoV-2 infection, the relationship between antibody titers, SARS-CoV-2 infection, and clinical outcomes remains to be fully elucidated in this vulnerable population.

Experiences and priorities of older adults during the COVID-19 pandemic.

BACKGROUND: Throughout the COVID-19 pandemic, older adults have been prioritized in public health campaigns to limit social interactions and 'cocoon' in their homes. This limits the autonomy of older people and may have unintended adverse consequences. AIMS: To ascertain the self-reported physical and psychological effects of 'cocooning' and the expressed priorities of older adults themselves during the pandemic. METHODS: This is a cross-sectional, survey-based study involving 93 patients aged 65 and older, attending geriatric medicine out-patient and ambulatory day hospital services or our in-patient rehabilitation units. Demographic data was obtained from the medical records. Frailty level was calculated using the Clinical Frailty Scale (CFS), and disease burden was calculated with the Charlson Comorbidity Index. RESULTS: Mean age was 79.1 (range 66-96), 24% had dementia, and most were mildly frail (CFS < 5). One-third reported new feelings of depression, decreased mobility, and loss of enjoyment as a consequence 'cocooning'. Loneliness was more prevalent amongst in-patients (38% vs 9%, p > 0.001). Respondents worried more about the risks of COVID-19 to their family than themselves. Expressed priorities varied from 'enjoying life as much as possible' to 'protecting the development of children'. CONCLUSIONS: Adverse consequences of 'cocooning' were commonly expressed amongst older adults. Public health policy should take into account the heterogeneity of this population and be sensitive to their self-expressed wishes and priorities.