Epidemiology of Neurological Disorders

Dr. Yeşim YASİN Fall-2013

Outline:

• Global burden of neurological disorders

• National burden of neurological disorders

• Most commonly seen neurological disorders: a

public health approach

• Prevention

Global burden of disesase

•Neurological diseases are becoming

increasingly important in terms of

public health throughout the world

and in Turkey.

Global burden of disesase

• The Global Burden of Disease report drew the

attention of the international health

community to the fact that the burden of

mental and neurological disorders had been

seriously underestimated by traditional

epidemiological methods that took into

account only mortality, not disability rates.

Global burden of disease

• The Global Burden of Disease report specifically

showed that while mental and neurological

disorders are responsible for about 1% of deaths,

they account for almost 11% of disease burden

worldwide

• Many conditions including neuropsychiatric disorders

and injuries cause considerable ill-health but no or

few direct deaths.

• Neuropsychiatric disorders and injuries in

particular were major causes of lost years of

healthy life as measured by DALYs,

• were significantly underestimated when measured

by mortality alone

Common neurological disorders

• Stroke

• Dementia

• Epilepsy

• parkinsonS disease

• Headeache disorders

• Multiple sclerosis

• Neuroinfections

• Neurological disorders

associated with

malnutrition

• Pain associated with

neurological disorders

• Traumatic brain disorder

Estimates of disability adjusted life years (DALYs)

Table 1. Number of DALYs for neurological disorders and as percentage of global DALYs projected for 2015 and 2030

neur

opsy

chia

tric

cat

egor

y

2%

4.3%

Percentage of total DALYs for selected

diseasesa and neurological disordersb

Neurological disoerders constitute slightly over 6% of total burden,

DALYs for individual neurological disorders as percentage of

total neurological disorders

Neurological disorders as percentage of total DALYs for 2005,

2015 and 2030 across income category

Neurological disorders contribute to 10.9%, 6.7%, 8.7% and 4.5% of the global burden of disease in high, upper middle, lower middle and low income countries, respectively, in 2005.

Estimates of deaths

Deaths attributable to neurological disorders as percentage of

total deaths, 2005, 2015, 2030

Deaths from selected neurological disorders as percentage of

total neurological disorders

Deaths

DALYs

Deaths and DALYs from

selected neurological

disorders as percentage

of total neurological

disordres

Neurological disorders as percentage of total deaths for 2005,

2015 and 2030 across World Bank income category

Neurological disorders constitute 16.8% of the total deaths in lower middle income

countries compared with 13.2% of the total deaths in high income countries.

Estimates of years of healthy life lost as a resultof disability (YLDs)

YLDs per 100 000 population associated with neurological disorders and other diseases and injuries with neurological sequelae and as percentage of total YLDs projected for 2015 and 2030

The number of YLDs per 100 000 population

associated with neurological disorders and other diseases and injuries with neurological sequelae

is projected to decline from 1264 in 2005 to 1109

in 2030

YLDs per 100 000 population associated with neurological disorders and other diseases and injuries with neurological sequelae and as percentage of total YLDs projected for 2015 and 2030

YLDs associated with Alzheimer and other dementias, however, are projected to increase by 38%.

Top five causes of YLDs among neurological disorders, by income

category YLDs per 100 000 population for neuroinfections, and the nutritional deficiencies and neuropathies category are highest for low income countries

neurological injuries, epilepsy and migraine, they are highest in upper middle income countries

For Alzheimer and other dementias they are highest for high income countries

YLDs associated with neurologicaldisorders by incomecategory

almost half of the burden in terms of YLDs attributable to neurological disorders is in low income countries followed by lower middle income countries

Turkey, Burden of Disease

Turkey, Burden of disease

BURDEN ATTRIBUTABLE TO SEVEN BASIC RISK FACTORS

• Alcohol use

• Insufficient

consumption of fruits

and vegetables

• Physical inactivity

• High colesterol

• Smoking

• High body mass

index

• High blood

pressure

Hypertension as a common risk factor

number of deaths attributed to hypertension, which refers to the fact that they could be prevented by keeping hypertension under control is 39.731 for cerebrovascular diseases

alcohol consumption-attributed deaths are mostly the consequences ischemic heartdiseases and hemorragic stroke. 2088 deaths caused by hemorrhagic stroke could be prevented by prevention of alcohol consumption

11109 deaths caused by ischemic stroke could be prevented by prevention of obesity

high cholesterol is among major risk factors of ischemic heart

diseases and ischemic stroke.

Prevention of high cholesterol could prevent 7.802 deaths

caused by ischemic stroke

Sufficient amount of physical activity could prevent 10.269 deaths caused by

ischemic stroke.

As for burden of disease which is preventable, physical activity could

prevent 101.578 DALY in ischemic stroke.

Prevention

•Many neurological disorders can be prevented!

Prevention

• Primary prevention

• Secondary prevention

• Tertiary prevention

Primary prevention

• High risk approach (individual approach)

• Population based approach

Prevention- high risk strategy • Elimination of the major risk factors.

• Controlling high blood pressure

• Lowering the level of blood cholesterol

• Quitting tobacco use

• Controlling diabetes

• Maintaining a healthy weight, body mass index

• Diet

• Exercising regularly

•Prevention and treatment of coronary hearth diseases

Prevention- population based strategy

• Raising awareness of health personnel about treatment and

prevention of neurological diseases

A comprehensivenational strategy; community-based health promotion and access to treatment can substantially decrease the burden associated with cerebrovascular diseases (stroke)

• Health promotion programmes to prevent risk factors.

• Smoke free air space

• Diabet control programmes

• Promoting and creating built or natural environments that encourage

and support physical activity.

Prevention-population based strategy

Prevention- population based strategy

• immunization programme for the prevention of

neuroinfections (poliomyelitis, neurological consequences of

infections)

• Road safety – prevention of traumatic brain injury

Traumatic brain injury is the leading cause ofdeath and disability in children and young adults

Tertiary prevention

• Using medication

• Rehabilitation

ASPIRIN In cases of acute stroke, aspirin is given as soon as CT or

MRI has excluded intracranial

haemorrhage.

Immediate aspirin treatment slightly

lowers the risk of early recurrent stroke and

increases the chances of survival free of

disability

about one fewer patient dies or is left dependent per

100 treated. However, because aspirin is applicable to so many stroke patients,

it has the potential to have a substantial public health

effect.

WHO recommendations

• Gain commitment from decision-makers • Increase public and professional awareness• Minimize stigma and eradicate discrimination• Strengthen neurological care within the existing

health systems • Incorporate rehabilitation into the key strategies • Establish links to other sectors• Define priorities for research

Conclusions

• Estimating the burden of diseases is difficult due to

• imperfect medical registration,

• variations in structure of patient referral and influence of

secondary diagnoses.

• Taking into account the current aging of the population, the

prevalence of some neurological diseases, such as CVA, Parkinson's

disease and dementia will rise.

• Priority setting for care and treatment is hampered by differences in

burden of illness on the individual and on the community level

THANK YOU!

52