A vaccine has been associated with ‘significantly lower’ dementia risk among the elderly. A substantial observational study published in Neurology discovered that receiving a high-dose flu jab is linked to a reduced risk of Alzheimer’s disease in adults aged 65 and above.

A recent study has highlighted a promising link between a particular vaccine and a notably lower risk of dementia among the elderly. Published in the journal Neurology, the research reveals that seniors who received a high-dose flu vaccine showed a decreased likelihood of developing Alzheimer’s disease.

This investigation was spearheaded by scientists at McGovern Medical School, part of UTHealth in Houston. According to the Alzheimer’s Society, currently, around 982,000 individuals in the UK live with dementia, with this number anticipated to climb to 1.4 million by 2040, as reported by the Mirror.

The study, titled ‘Risk of Alzheimer Dementia After High-Dose vs Standard-Dose Influenza Vaccination’, analyzed the health records of nearly 165,000 older individuals who were administered either a high-dose or standard-dose flu vaccine. Results indicated that those who received the high-dose version experienced a nearly 55% reduction in Alzheimer’s risk over a period of approximately two years.

In previous research, the same team found that the standard-dose vaccine was associated with a 40% reduced risk over four years. The high-dose flu vaccine contains quadruple the amount of antigen—the substance that prompts an immune response—compared to standard vaccines. The study’s authors suggest that these enhanced vaccines provide superior protection against flu infections, which may help reduce severe illness and related systemic inflammation that can lead to neuroinflammation and neurodegeneration.

While both men and women demonstrated a reduced risk of Alzheimer’s following the high-dose flu vaccine compared with the standard-dose alternative, the protective benefit appeared more consistent and endured longer in women.

The study’s advantages include its substantial sample size and its methodology, which compared vaccinated cohorts. The researchers acknowledged limitations, including “healthy-user bias”, the likelihood that people who pursue high-dose vaccines also engage with health care in ways that influence dementia risk, and dependence on claims data that may have incorrectly classified Alzheimer’s disease.

The researchers say additional studies are needed to better understand vaccine dosage, immune responses, and long-term cognitive outcomes. Further investigation is also needed to establish whether vaccination might affect disease progression once symptoms have emerged.

In England, over 18.2 million patients registered with a GP were recorded as having received the flu jab during the 2024 to 2025 season. As of late November 2025, uptake figures showed that 70% of people aged 65 and over, 42% of expectant mothers, and 71% of care home residents were vaccinated.

Who should have the flu vaccine?

According to the NHS, the flu jab is recommended for people in the UK who face a greater risk of severe illness from flu. It’s provided on the NHS annually in autumn or winter. You can get the free NHS flu vaccine if you:

• are aged 65 or over
• have certain long-term health conditions
• are pregnant
• live in a care home
• are the main carer for an older or disabled person, or receive a carer’s allowance
• live with someone who has a weakened immune system

Frontline health and social care workers can also receive a flu vaccine through their employer.

Symptoms of Alzheimer’s disease and what causes it?

According to the NHS, Alzheimer’s disease is the most common cause of dementia in the UK. It says: “Dementia is the name for a group of symptoms associated with an ongoing decline of brain functioning. It can affect memory, thinking skills and other mental abilities. The symptoms of Alzheimer’s disease progress slowly over several years. Sometimes these symptoms are confused with other conditions and may initially be put down to old age.” In the initial stages, the primary indicator of Alzheimer’s disease is memory loss. For instance, someone with early-stage Alzheimer’s disease may:

As Alzheimer’s disease advances, memory difficulties will deteriorate. Additional symptoms may also emerge, such as:

• forget about recent conversations or events
• misplace items
• forget the names of places and objects
• have trouble thinking of the right word
• ask questions repetitively
• show poor judgement or find it harder to make decisions
• become less flexible and more hesitant to try new things

The conduct of those living with Alzheimer’s disease can also alter. For example, they may:

• increasing confusion and disorientation – for example, getting lost, or wandering and not knowing what time of day it is
• obsessive, repetitive or impulsive behaviour
• delusions (believing things that are untrue) or feeling paranoid and suspicious about carers or family members
• problems with speech or language (aphasia)
• disturbed sleep
• changes in mood, such as frequent mood swings, depression and feeling increasingly anxious, frustrated or agitated
• difficulty performing spatial tasks, such as judging distances
• seeing or hearing things that other people do not (hallucinations)

A range of further symptoms may also manifest as Alzheimer’s disease progresses, such as:

• be aggressive, such as hitting or shouting
• become upset or restless
• call out or repeat the same question again and again

A number of other symptoms may also develop as Alzheimer’s disease progresses, such as:

• difficulty eating and swallowing (dysphagia)
• difficulty changing position or moving around without assistance
• weight loss – sometimes severe
• unintentional passing of urine (urinary incontinence) or stools (bowel incontinence)
• gradual loss of speech
• significant problems with short and long-term memory