Dementia

Overview

Background

An estimated 637,000 people in the UK have dementia syndrome and the annual cost of their care is £17 billion(Alzheimer’s Society 2007). Alzheimer’s disease is the commonest type of dementia (affecting around 60% of those with dementia), followed by vascular dementia (20–25%) and dementia with Lewy bodies (10–15%)(Overshott 2005; DTB 2003).

About 80% of people with dementia will have behavioural changes or psychological symptoms at some time (Overshott 2005), which can reduce quality of life for both patients and carers, and often result in transfer to residential care and higher costs(Finkel 2000; O’Donnell 1992; Lawlor 2002; Donaldson 1997). The symptoms can include anxiety, depressed mood, psychotic symptoms, and behavioural symptoms such as aggression, agitation, wandering, sexual disinhibition, and screaming and swearing(Finkel 1997). Psychotic symptoms such as delusions and hallucinations occur in 30–50% of all patients with dementia(Jeste 2000), and in about 80% of patients with dementia with Lewy bodies(McKeith 2006).

There are 2 main types of medication used to treat Alzheimer’s disease – cholinesterase inhibitors and NMDA receptor antagonists. Cholinesterase inhibitors include donepezil hydrochloride (Aricept), rivastigmine (Exelon) and galantamine (Reminyl). The NMDA receptor antagonist is memantine (Ebixa). Drugs may also be used to treat symptoms of dementia, for example, antipsychotic drugs, antidepressants, anti-anxiety drugs and hypnotics(Burns 2009). However, the generally recommended practice for such symptoms of dementia is to try non-drug methods first (e.g. behavioural and psychological interventions, occupational activities, environmental approaches), unless the patient is severely distressed or there is an immediate risk of harm to themselves or others(DTB 2003; NICE 2006). NICE guidelines recommend that people with dementia with mild-to-moderate non-cognitive symptoms should not be prescribed antipsychotic drugs, and that those with severe non-cognitive symptoms (i.e. psychosis and/or agitated behaviour causing significant distress) should only be offered treatment with an antipsychotic drug if specific conditions have been met(NICE 2006).

Clinical evidence

One systematic review found that the evidence available for acupuncture does not demonstrate effectiveness in Alzheimer’s disease (Lee 2009),although only three randomised controlled trials (RCTs) were located for this. By contrast, a review for dementia in general found 22 RCTs, which demonstrated a significant positive advantage for acupuncture over control groups (Gu 2008). Since most of the trials were for vascular dementia, it’s notable that a Cochrane review one year earlier had found no suitable RCTs at all for this condition (Peng 2007)

There have been several randomised controlled trials published since these systematic reviews, all with promising results. All are for vascular dementia (not Alzheimers) and all are from China. All of them compared acupuncture to medication; two also used a combined acupuncture plus medication group. In five trials, acupuncture was significantly better than medication (Zhang 2011, Chen 2011, Wang 2010, Zhang 2008, Liu 2008b) and in three it was similar in effect (Zhao 2009, Chen 2009, Liu 2008a). Various different acupuncture treatment modalities were used: manual needling (Zhang 2011, Liu 2008a), electroacupuncture (Zhao 2009, Zhang 2008, Liu 2008b), moxibustion (Chen 2011, Wang 2010) and ear taping/pressing (Chen 2009). Most studies used recognised outcomes measures relevant to dementia and some also investigated possible biochemical mechanisms (see below).

Despite this, there is certainly a need for larger, better quality trials, preferably from a wider range of countries.

Potential mechanisms

In general, acupuncture is believed to stimulate the nervous system and cause the release of neurochemical messenger molecules. The resulting biochemical changes influence the body’s homeostatic mechanisms, thus promoting physical and emotional well-being.

Research has shown that acupuncture treatment may specifically help in dementia by:

• regulating neuropeptide substances (somatostatin and arginine vasopressin) relevant to learning and memory (Chen 2011; Wang 2010);
• reducing the levels of 8-OHdG (Shi 2012) and decreasing lipid peroxidation in the brain (Zhu 2010; Yang 2007), suggesting that acupuncture helps to prevent oxidative damage;
  activating certain cognitive-related regions in the brain(Wang 2012);
• decreasing the overproduction of nitric oxide and strengthening the ability to eliminate free radicals (He 2012);
• decreasing cholinergic neuron damage and reducing the abnormal activation and hyperplasia of astrocytes (Miao 2009);
• decreasing the number of activated glial cells so as to protect the neurons (Zhu 2009);
  lowering acetylcholinesterase activity (Yang 2007);
• suppressing vascular dementia-induced increase of interleukin-1beta and tumor necrosis factor-alpha levels in the hippocampus (Li 2007);
• improving glucose metabolism in the bilateral frontal lobes, bilateral thalamus, temporal lobe and lentiform nucleus (Chen 2006);
• acting on areas of the brain known to reduce sensitivity to pain and stress, as well as promoting relaxation and deactivating the ‘analytical’ brain, which is responsible for anxiety and worry (Hui 2010; Hui 2009);
• increasing the release of adenosine, which has antinociceptive properties (Goldman 2010).