Dementia — NZ Condition Guide | KiwiMeds

What is Dementia?

Dementia is not a single disease but a group of conditions characterised by a decline in memory, thinking, behaviour, and the ability to perform everyday activities. Alzheimer’s disease is the most common type, accounting for 60–70% of cases. Dementia affects around 70,000 New Zealanders and numbers are growing as the population ages.

Overview

Early dementia symptoms include memory loss that disrupts daily life (particularly remembering recent events), difficulty with planning or problem solving, confusion with time and place, trouble with familiar tasks, problems with language (word-finding difficulties), poor judgement, withdrawal from social activities, and personality or mood changes. Symptoms progress over time. Dementia is not a normal part of ageing — if you are concerned about your memory or that of a family member, see a GP.

Treatment in New Zealand

There is currently no cure for most types of dementia. Medicines can help manage symptoms: cholinesterase inhibitors (donepezil, rivastigmine, galantamine — all funded by Pharmac) improve memory and behaviour in Alzheimer’s disease. Memantine is used for moderate-severe Alzheimer’s. Non-pharmacological approaches — cognitive stimulation, structured activity, carer support — are important. Managing cardiovascular risk factors (blood pressure, cholesterol, diabetes) may slow progression.

NZ-Specific Information

Alzheimer’s NZ (alzheimers.org.nz) provides information, support, and carer resources. Specialist memory services are available through geriatric medicine and neurology services. Carer support is available through Age Concern NZ and district health services. Advanced care planning is important — decisions about future care should be made while the person still has capacity.

Frequently Asked Questions

Is dementia the same as Alzheimer’s? No — Alzheimer’s disease is the most common cause of dementia, but dementia can also be caused by vascular disease, Lewy bodies, and frontotemporal changes. Can dementia be prevented? Risk can be reduced by managing cardiovascular risk factors, staying mentally and physically active, maintaining social connections, and not smoking.

Supplements That May Support Management

⚠️ Important: The supplements listed below have varying levels of clinical evidence. They are not a substitute for prescribed medications and should only be considered as adjunctive support under the guidance of a qualified healthcare professional. Always inform your GP or pharmacist before commencing any supplement, as interactions with prescribed medicines are possible.

• Omega-3 Fatty Acids (DHA-dominant) — DHA is the predominant omega-3 fatty acid in brain tissue and is essential for neuronal membrane integrity and synaptic function. Supplementation may modestly slow cognitive decline in those with mild cognitive impairment, though evidence in established Alzheimer’s disease is less strong. DHA-dominant formulations (500–1000 mg DHA/day) are most studied.
• B Vitamins (B6, B12, Folate) — Homocysteine reduction — Elevated plasma homocysteine is a significant and modifiable risk factor for brain atrophy and cognitive decline. The OXFORD OPTIMA trial demonstrated that B vitamin supplementation in those with elevated homocysteine significantly slowed brain atrophy and cognitive decline. Supplementation is most beneficial in those with documented elevated homocysteine.
• Vitamin D — Vitamin D deficiency is associated with significantly increased dementia risk (1.5–2x higher) in large prospective studies. Supplementation in deficient older adults is recommended for neurological and cardiovascular health.
• Ginkgo Biloba (EGb 761 extract) — The standardised Ginkgo biloba extract EGb 761 at 240 mg/day has the strongest evidence among herbal supplements for dementia, with randomised trial evidence supporting stabilisation of cognitive function and activities of daily living in mild-to-moderate Alzheimer’s disease.
• Lion’s Mane Mushroom (Hericium erinaceus) — Lion’s mane stimulates nerve growth factor (NGF) synthesis, supporting neuronal maintenance and regeneration. Small clinical trials have demonstrated improvements in cognitive function scores in mild cognitive impairment with 250 mg three times daily.

Relevant Vaccinations

Individuals living with dementia may benefit from the following vaccinations. Please discuss your vaccination status with your GP or practice nurse, as eligibility and funding through the New Zealand National Immunisation Schedule may apply.

• Influenza (annual) — Influenza infection has been associated with increased dementia risk and accelerated cognitive decline. Annual vaccination is funded and strongly recommended for people with or at risk of dementia.
• Pneumococcal — Recommended for adults aged 65+ and those with dementia. Pneumonia-related hospitalisation accelerates functional and cognitive decline.
• Shingles (Shingrix) — Recent evidence suggests shingles vaccination reduces the risk of dementia onset. Recommended for adults 50+.
• COVID-19 — COVID-19 and post-COVID neurological complications accelerate cognitive decline in people with existing dementia. Maintaining vaccination is strongly recommended.

Dietary Guidance

Evidence-based dietary modifications play a meaningful role in the management of dementia. The following foods are generally recommended as part of a balanced, condition-appropriate diet. A referral to a registered dietitian may be beneficial for personalised nutritional planning.

• Mediterranean or MIND dietary pattern — The MIND diet (Mediterranean-DASH Intervention for Neurodegenerative Delay) is the best-evidenced dietary pattern for dementia prevention and cognitive preservation, combining Mediterranean and DASH elements. It specifically emphasises green leafy vegetables (6+ servings/week), berries, nuts, olive oil, fish, and whole grains.
• Oily fish (brain DHA source) — Regular dietary DHA from fatty fish is the most important nutritional factor for brain health maintenance. Aim for 2–3 servings weekly.
• Berries (especially blueberries) — Blueberry consumption has the most consistent evidence for cognitive benefit, with flavonoids supporting cerebrovascular function and neuronal signalling.
• Extra virgin olive oil — Oleocanthal in EVOO has anti-amyloid properties, promoting clearance of beta-amyloid plaques associated with Alzheimer’s pathology. Regular consumption (≥4 tablespoons/day in the Mediterranean diet) is associated with reduced dementia risk.
• Limit: ultra-processed foods, saturated fat, refined sugar — These promote neuroinflammation, cerebrovascular disease, and insulin resistance — all established dementia risk factors. The MIND diet specifically identifies red meat, butter, margarine, cheese, pastries, and fried/fast food as foods to limit.

Related Conditions & Medications

Related conditions: Hypertension, Type 2 Diabetes.