Prevalence, incidence and Pharmacoeconomics of dementia

Abstract

Dementia has challenged scientists, policy-makers, economists and society with a number of questions which remains unanswered even now. These unanswered questions have lead to steady rise in treatment costs. Government has a strategy to provide care to all the affected patients of dementia but have no strategy to deal with rise in demand for treatment and cost of treatment.

Statistics show that in 2010 there are 821,884 people who are afflicted with dementia in UK and it is expected to cost economy an exorbitant amount of £23 billion. 1.3 % of the UK population is suffering from dementia but it indirectly affects 42% of the population who live with these affected people provides them care and support, so social impact of dementia on society cannot be computed.

Keywords: Dementia, prevalence, incidence.

Introduction

What is dementia?

Dementia is a continuously escalating disease and is irreversible and causes an overall deterioration of mental abilities due to loss of brain cells.

People with dementia appears normal and exhibit characteristics of a normal person but with disease progressing they exhibit severe impairment in cognitive abilities like memory impairment, aphasia, apraxia, agnosia, aggression, sleep disturbances, affected problem solving abilities, as a result a patient suffering from dementia cannot carry out normal activities & relationships (About.com,2009).

Symptoms of dementia besides above mentioned are severely affected judgment and reasoning abilities with loss of consciousness (wrong diagnosis, 2010).

Often symptoms of other mental illness like psychosis and depression are similar to dementia symptom called as delirium are confused with dementia but clinically dementia is established only when symptoms exists for more than 6 months (NHS choice, 2009).

Dementia could be differentiated into 2 major types-

1. Static- which is caused by injury in head

2. Progressive- which is due to steady long period degradation in mental skills caused by an damage or any diseased condition

Types of dementia

Alzheimer’s disease, Dementia with Lewy bodies (DLB), frontotemporal dementia, vascular dementia and mixed dementias (medicine net.com,2009).

Disease conditions that can cause dementia are-Dementia in Parkinson’s disease, HIV associated dementia, Dementia Pugilistica, Corticobasal degeneration (CBD), Creutzfeldt-Jakob Disease (CJD), Niemann-Pick disease, Batten diseas, Lafora body disease and Huntington's disease is a hereditary disease which causes dementia (medicine net.com, 2009).

Parts of brain affected in dementia

Occipital lobes, parietal lobes, frontal lobes, cerebellum and other movement controlling areas (Fernandez et al.2010)

Risk factors of dementia

Age- It is the biggest risk factor for dementia. As the risk of getting dementia increases with age so elderly people are more at risk but that does not mean that it cannot affect young people as Niemann-Pick disease, Batten disease, Lafora body disease can affect children and in UK alone there are more than 15,000 people below the age of 65 who are suffering wit dementia (medicine net.com, 2009) .

Genetics- scientists have recently discovered numerous genes are involved in the development of dementia presence of these genes in a person significantly increases his chances of getting dementia (medicine net.com, 2009).

Smoking and alcohol use- researchers have revealed that smokers suffer from progressive degradation of mental abilities and risk of getting dementia increases significantly. Also chronic use of alcohol increases the risk of getting dementia (medicine net.com, 2009).

Atherosclerosis- causes plaque formation thereby hardening and narrowing of major arteries, it obstructs the blood supply to various parts of brain and can cause stroke (medicine net.com, 2009).

Cholesterol- elevated levels of low density lipoprotein significantly increases the risk of angina, heart attack and stroke and hence increased risk of developing vascular dementia (medicine net.com, 2009).

Homocysteine- it is observed that in there is a link between plasma homocysteine levels and getting vascular dementia or Alzheimer’s and people who are at risk have elevated levels of this amino acid (medicine net.com, 2009).

Mild cognitive impairment- people with moderately affected mental abilities are at risk of their condition progressing to severe dementia. These people are at a high risk than rest population but it is mandatory that these people will surely develop dementia (medicine net.com, 2009).

Down syndrome- studies have revealed that many of the Down syndrome patients evolve typical neurofibrillary tangles and plaques of Alzheimer’s disease (medicine net.com, 2009).

Prevalence and incidence of dementia (give definition and various studies)

Prevalence of a disease could be defined as “the total cases of the disease in the population at a given time divided by the number of individuals in the population”. It gives a projection of how commonly the disease is occurring in the society (Ferri et al, 2005).

Incidence of a disease could be defined as “the risk of developing new condition within a specified period of time”. It is represented as proportion or rate (Ferri et al, 2005).

Until 2008 more than 30 million have been affected with dementia worldwide and it is projected that by 2050 patients of dementia will cross 100 million mark. In UK, almost 1.3% of the total population which amounts to 821,884 people is suffering from dementia. By 2051 it projected that UK will have 1,735,087 dementia patients (Ferri et al, 2005).

Important fact is that 50% of the dementia cases in Caucasian society are Alzheimer’s disease showing high prevalence of the dementia in western world.

Until early 21st century it was believed that dementia is a disease that affects older people above 65 years of age but in UK alone 15,034 people with dementia have been reported who are below 65 years of age and this group includes children as well (Fernandez et al, 2010).

Below in table 1 it is depicted that currently in 2010 age group 80-84 have highest number of patients but as the society will modernize patients in age group 8084 will increase along with other groups such 85-89 and 90-94 years age group. Hence in this table impact of lifestyle is clearly shown (refer table 1).

Table 1. Showing the number of people affected with dementia in various age groups Adapted from Dementia UK: The Full Report to the Alzheimer's Society produced by King's College London and the London School of Economics

In table 2 different age groups and prevalence rates of dementia in males and females have been shown below. We can see that in Europe prevalence rates in males and females were very low and similar till age group 55-59 years, while prevalence rates in UK showed mixed trends in males and females. But as the age increases in Europe and UK males show lesser prevalence rates than females. So unknown factor not mentioned in the study increases the prevalence rates in females (refer table 2).

Table 2. showing % prevalence rates of dementia in UK Adapted from Dementia UK: The Full Report to the Alzheimer's Society produced by King's College London and the London School of Economics

In table 3 number of people affected with dementia in UK have been shown and we can see the highest number of dementia patients are in England contributing significantly to the total number of dementia patients in UK (refer table 3).

Engla

nd (2005)

Scotla

nd (2010)

Wale

s (2005)

Northern

Islan

d (2010)

UK (2010)

0

100,000

200,000

300,000

400,000

500,000

600,000

700,000

800,000

900,000

Series 1

Table 3. showing number of people In UK affected with dementia Adapted from Dementia UK: The Full Report to the Alzheimer's Society produced by King's College London and the London School of Economics

Table 4 shows number of patients affected with dementia in developing countries and it indicates that impact of genetics and lifestyle of patients on dementia.

Singapore Indonesia Malaysia Myanmar

Philippines Thailand Viet Nam

No. of people affected with Dementia

22,000 600,000 60,000 130,000 175,000 250,000 275,000

Table 4.No. of people affected by dementia in South-east Asia in 200 Adapted from Dementia UK: The Full Report to

the Alzheimer's Society produced by King's College London and the London School of Economics

In Table 5 below risk of developing dementia has been projected and we can see that risk of getting dementia till 40-44 years is 1in 10,000 but as the age increase to 60-64 chances of getting dementia increases to 1 in 1000 and in age group 85-89 risk of dementia increases to 1 in 10.

Table 5. showing risk of developing dementia Adapted from Dementia UK: The Full Report to the Alzheimer's Society produced by King's College London and the London School of Economics

Treatment

National institute of health and clinical excellence (NICE) recommends two kinds of treatment for dementia.

1. Psychological & Behavioural treatment Behaviour management consists of special ordered exercises carried out by carers. Cognitive stimulation involves a memory-stimulating, problem-solving and interactive sessions carried out by carers (NHS choice,2009).Reality orientation therapy aims to restore the person with his senses and makes him aware of this going on around him (NHS choice,2009). Multisensory stimulation uses a variety of techniques, including lighting, relaxing music, sounds, massage cushions and sensations to stimulate the brain (NHS choice,2009).

2. Medical treatment

Although medical treatment is not very successful but the therapy is aimed at preventing the progression of disease but cannot recover the damage done.

Acetylcholinesterase inhibitors blocks the degradation of acetylycholine e.g donepezilAnti-psychotic drugs are used to treat the symptoms of dementia like depression, dizziness etc (NHS choice,2009).Glutamate blockers e.g. memantine(NHS choice,2009).

Prevention

Studies have unfolded the mystery of dementia and factors that can influence the development of dementia. Researchers have suggested that people with blood glucose level under control are low at risk to dementia (medicine net.com,2009)

Studies also have revealed that people who exercise intellect stimulating activities, such as social communications with other people, chess, and crossword puzzles and playing a musical instrument are at a lower risk of developing dementia (medicine net.com,2009).

Other factors that can influence development of dementia development are plasma homocysteine concentration, lowering cholesterol levels, lowering blood pressure, exercise and controlling inflammation (medicine net.com,2009).

World market for dementia

Worldwide treatment cost of dementia varies from country to country and also depends upon the types of medicines available. Overall estimated cost of dementia in 2007 was US$315.4 Billion, which includes medicines cost and care cost (Alzheimer’s disease international, 2009).

The mean life long treatment and care cost for dementia is $174,000(Alzheimer’s disease international, 2009).

Dementia treatment costs in some of the South-east Asian countries are given bellow:

Singapore US$391 million Indonesia US$2,128 millionMalaysia US$511 million Myanmar US$118 millionPhilippines US$601 million Thailand US$1,330 millionViet Nam US$751 million

The worldwide drug market for dementia is estimated to be US$50.4 Billion (major pharma markets like U S, UK, and Japan accounts for US$ 5.5 Billion of the worldwide sales) (Alzheimer’s disease international, 2009).

The latest drug approved for treatment of dementia is Aricept (donezpil) which alone occupies a market of $2.5 Billion (refer table 6).

Table 6. showing worldwide sales of dementia drugs

Cost of treatment in UK

The cumulative cost of treating late onset dementia in UK is estimated to be mean value of £27,647 per person. To treat 1.3% of the dementia affected population of UK, it costs NHS annually over £23 Billion. Sum of £23 billion comprises of income lost by people providing them care, who have to leave their jobs or have to reduce working hours. Reduction in income affects economy indirectly by reduction in the amount of taxes paid to the Exchequer. In 2007 Exchequer lost £123 million pounds in terms of taxes and due to reduction in working hours £ 690 pounds were lost. In 2002, in Scotland a law (Receipt of Attendance Allowance) was passes which entitled dementia patients free care which added an additional burden of £919 pounds on the economy(Fernandez et al., 2010).

It is projected that by 2026, treatment cost of dementia will increase by 45 % to £34.6 billion. This increase in the cost is attributed to increase in the service cost which will add an additional £9 billion. This cost is expected to increase further due to increase in the pay and inflation each year and it could add a maximum amount of £47.5 billion (Fernandez et al., 2010).

All these factors have a huge economic impact on the treatment of mental health.

Table 6.showing the cost associated with prevalent diseases adapted from ( Fernandez, Leal & Gray,2010)

Figure 1. showing the cost associated with different services for dementia adapted from ( Fernandez, Leal & Gray,2010)

Table 7 below shows the comparative cost between dementia and other prevalent diseases like cancer, heart disease and stroke. It is clearly evident from the statistics that cost of treatment

of cancer per year per patient is £5,999 and that of heart disease is £3,455 while the mean salary in UK is £24,700 and as already mentioned cost of treatment on dementia is £27,647.

Proportion of older people in receipt of home care

Proportion of older people who receive day care

Hourly home care cost

England 3.9% 1.7%. £9.20 - £22.10

Scotland 6.9% 1.3% £740- £187 per person per year

Wales 4.3% 1.6% £17.6

Northern Ireland 2.4 % 1.1 % -

Table 7. showing the annual cost of treating one dementia patient adapted from ( Fernandez, Leal & Gray,2010)

Cost effective treatment for dementia & Potential savings

As no such medicine is available till now which can cure or reverse the effects of dementia treatment is aimed at preventing further progression of the disease by symptomatic drugs and behavioral & psychological exercises.

NICE recommends psychological and behavioral therapy as the first line treatment for dementia. Acetylcholinesterase inhibitors has been recommended by NICE treatment for moderate dementia. Early detection and prevention of further progression of disease will not only benefit the patient but will also reduce the utilization of services which could be provided to other needy people and can save cost (NHS choice , 2009).

table 8 showing the comparative increasing cost of drugs and their cost effectivenessadpated from NHS choice, 2009

Recently in a study conducted has revealed that long time exposure of NSAID’s can lower the risk of vascular dementia by controlling stroke and can also control inflammation reducing chances of Alzheimer’s disease(Fernandez et al., 2010).

In table 8 shown below are various neurological diseases and potential savings that could be achieved by introducing an effective intervention and statistics show that maximum saving could be achieved by an effective intervention.

A c e ty lc h o lin e s tera se in h ib ito rs (A C h Is ) c o s t a ss o c ia te d fo r 1 Q A L Y w a s £ 2 3 ,0 0 0 to £ 3 5 ,0 0 0 , d e p e n d in g o n th e c h o ic e o f d ru g .A ric e p t c o s ts £ 2 .5 0 a d a y

F o r m ild d e m e n ti a , e s ti m a te s w e re fro m £ 5 6 ,0 0 0 to £ 7 2 ,0 0 0 Q A L Y .

F o r tre a ti n g p e o p le w ith m o d e ra te ly s e v e re -to -se v e re d e m e n ti a u s in g m e m a n ti n e w a s e sti m a te d a s £ 7 0 ,0 0 0 to £ 9 0 ,0 0 0

Table 9. shows the potential savings that could be achieved by controlling neurological diseases

References

About.com, 2009 [available online] http://alzheimers.about.com/od/diagnosisofalzheimers/tp/Types-of-Dementia.htm

Alzheimer’s disease international, 2009 [available online] http://www.alz.co.uk/media/releases.html [accessed on 6 Mar 2010]

Dementia (2006) NICE: Supporting people with dementia and their carers in health and social care [available online]disease/book-diseases-4c.htm [accessed on 6 Mar 2010]

Fernandez, R.L., Leal, J., Gray, A. (2010). Dementia 2010. Alzheimer’s research trust. 1-12

Ferri, C., et al. (2005). Study of dementia prevalence.  The Lancet . Vol 366.2112-2117

Medicine net.com, 2009 [available online] http://www.medicinenet.com/dementia_pictures_slideshow/article.htm [accessed on 6 Mar 2010]

Medline Plus, 2010 [available online] http://www.nlm.nih.gov/medlineplus/ency/imagepages/17146.htm

NHS choices, 2009 [available online] http://www.nhs.uk/Conditions/Dementia/Pages/Diagnosis.aspx

Wrong diagnosis, 2010 [ available online] http://www.wrongdiagnosis.com/a/alzheimers_