Editor’s note: Find the latest COVID-19 news and guidance in Medscape’s Coronavirus Resource Center.
When 23 frail elderly patients in Norway died in early 2021 shortly after they had received an mRNA-based vaccine against COVID-19, Norwegian health authorities cautioned physicians to conduct more thorough assessments of patients prior to immunization, and launched an investigation into the safety of the BNT162b2 vaccine (Comirnaty; Pfizer-BioNTech).
Now, the results of that investigation and of a subsequent larger study of nursing home residents in Norway have shown no increased risk for short-term mortality following COVID-19 vaccination in the overall population of elderly patients. The new research also showed clear evidence of a survival benefit compared with the unvaccinated population, Anette Hylen Ranhoff, MD, PhD, said at the annual meeting of the European Geriatric Medicine Society, held in a hybrid format in Athens, Greece, and online.
“We found no evidence of increased short-term mortality among vaccinated older individuals, and particularly not among the nursing home patients,” said Ranhoff, a senior researcher at the Norwegian Institute of Public Health and professor at University of Bergen, Norway. “But we think that this [lower] mortality risk was most likely a sort of ‘healthy-vaccinee’ effect, which means that people who were a bit more healthy were vaccinated, and not those who were the very, very most frail.”
“We have more or less the same data in France about events, with very high rates of vaccination,” said session moderator Athanase Benetos MD, PhD, professor and chairman of geriatric medicine at the University Hospital of Nancy in France, who was not involved in the study.
“In my department, a month after the end of the vaccination and at the same time while the pandemic in the city was going up, we had a 90% decrease in mortality from COVID in the nursing homes,” he told Ranhoff.
Frail elderly patients were not included in clinical trials of COVID-19 vaccines, and although previous studies have shown a low incidence of local or systemic reactions to vaccination among older people, “we think that quite mild adverse events following vaccination could trigger and destabilize a frail person,” Ranhoff said.
As reported Jan. 15, 2021, in BMJ, investigation by the Norwegian Medicines Agency (NOMA) into 13 of the 23 reported cases concluded that common adverse reactions associated with mRNA vaccines could have contributed to the deaths of some of the frail elderly patients
Steinar Madsen, MD, NOMA medical director, told BMJ “we are not alarmed or worried about this, because these are very rare occurrences and they occurred in very frail patients with very serious disease.”
Health Authorities Investigate
In response to the report and at the request of the Norwegian Public Health Institute and NOMA, Ranhoff and colleagues investigated the first 100 deaths among nursing-home residents who received the vaccine. The team consisted of three geriatricians and an infectious disease specialist who sees patients in nursing homes.
They looked at each patient’s clinical course before and after vaccination, their health trajectory and life expectancy at the time of vaccination, new symptoms following vaccination, and the time from vaccination to new symptoms and to death.
In addition, the investigators evaluated Clinical Frailty Scale (CFS) scores for each patient. CFS scores range from 1 (very fit) to 9 (terminally ill, with a life expectancy of less than 6 months who are otherwise evidently frail).
The initial investigation found that among 95 evaluable patients, the association between vaccination and death was “probable” in 10, “possible” in 26, and “unlikely” in 59.
The mean time from vaccination to symptoms was 1.4 days in the probable cases, 2.5 days in the possible cases, and 4.7 days in the unlikely cases.
The mean time from vaccination to death was 3.1, 8.3, and 8.2 days, respectively.
In all three categories, the patients had mean CFS scores ranging from 7.6 to 7.9, putting them in the “severely frail” category, defined as people who are completely dependent for personal care but seem stable and not at high risk for dying.
“We have quite many nursing home residents in Norway, 35,000; more than 80% have dementia, and the mean age is 85 years. We know that approximately 45 people die every day in these nursing homes, and their mean age of death is 87.5 years,” Ranhoff said.
Ranhoff and colleagues also looked more broadly into the question of potential vaccine-related mortality in the total population of older people in Norway from the day of vaccination to follow-up at 3 weeks.
They conducted a matched cohort study to investigate the relationship between the mRNA SARS-CoV-2 vaccine and overall death among persons aged 65 and older in the general population, and across four groups: patients receiving home-based care, long-term nursing home patients, short-term nursing home patients, and those not receiving health services.
The researchers identified a total of 967,786 residents of Norway aged 65 and over at the start of the country’s vaccination campaign at the end of December, 2020, and they matched vaccinated individuals with unvaccinated persons based on demographic, geographic, and clinical risk group factors.
Ranhoff showed Kaplan-Meier survival curves for the total population and for each of the health-service states. In all cases there was a clear survival benefit for vaccinated vs. unvaccinated patients. She did not, however, provide specific numbers or hazard ratios for the differences between vaccinated and unvaccinated individuals in each of the comparisons.
The study was supported by the Norwegian Institute of Public Health. Ranhoff and Benetos reported no conflicts of interest.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.