PUBLIC HEALTH

Figure 3.1 Deaths caused by neurological disorders

Disability

Disability can be defined as a physical or mental impairment that substantially limits one or more major life activities. Disabilities can be caused by disease, trauma or other health conditions and may require ongoing medical care. Many neurological diseases result in disability, and lasting disability is the most common outcome after a neurological illness or injury. The main neurological disabilities are impairment of motor or cognitive functions. These include a wide range, from loss of mobility in stroke and paraplegia to cognitive impairment in head injury. Other lasting disabilities include epilepsy and loss of sight or hearing. Disability may be a fixed disability as occurs in head injury or progressive as in dementia. Neurological disorders contribute >14% of the total burden of YLDs in Africa. (Fig. 3.2). The causes include infections 4.2%, nutrition/neuropathies 4%, head injuries 3.6%, epilepsy 0.9%, migraine 0.6%, stroke 0.4%, and neurodegeneration 0.4%.

Figure 3.2 Disability caused by neurological disorders

Mental Disease

Neuropsychiatric disorders including depression, psychoses, alcohol abuse and substance use account for significant proportion of global disease burden >14% of YLDs. These frequently coexist with neurological disorders but are not covered in this textbook. Neurological and mental disease together account for >28% of total YLDs in Africa.

Death and disability (DALYs)

Globally neurological disorders contribute >6% of the total DALYs. In Africa NDs account for about 3% of total burden of disease as measured by DALYs. The main neurological disorders contributing to DALYs in Africa are stroke 1.1%, infections (mostly tetanus & meningitis) 0.9%, and epilepsy 0.5%. However this is an underestimate as the burden of HIV related neurological disorders is not included in this category by WHO estimate. HIV/AIDS on its own accounts for over 5% of total DALYs worldwide, most of which occurs in SSA.

HEALTH PROMOTION AND DISEASE PREVENTION

Health promotion can be defined as the process of enabling people to increase control over their health and its determinants, and thereby improve their lives. The primary means of health promotion occurs through developing a healthy public policy that addresses the prerequisites of health such as income, housing, food, water, security, employment, transport and quality working conditions.

Disease prevention (preventive medicine or preventive care) refers to measures taken to prevent illness or injury, rather than curing them. The major preventable risk factors for global disease are outlined below in Table 3.1. Prevention strategies are designed to decrease morbidity and mortality and are categorised as primary, secondary and tertiary prevention (Table 3.2). These strategies are aimed either at the general population or targeted at selective subgroups of the population. Specific examples of prevention strategies in neurology are presented in Table 3.3.

Table 3.1 Major preventable risk factors for disease globally, WHO

Risk factor	% global disease burden
Under nutrition Over nutrition Unsafe sex Tobacco Alcohol Unsafe water/sanitation/hygiene	15 13 6 4 4 4

Table 3.2 Prevention of disease

Primary	preventing a disease before it happens
Secondary	decreasing disease severity through early detection, diagnosis and treatment
Tertiary	treating & managing disease complications to increase quality of life, reduce disability & prevent death

Table 3.3 Examples of prevention strategies in neurological disorders in Africa

Prevention strategies	Measures	Expected outcome
Primary prevention	vaccination increased exercise healthy diet low salt diet stop smoking reduce cholesterol wearing seatbelts/helmets	prevents tetanus combined with secondary measures decreases stroke by 70% decreases death/head injury by 40-50%
Secondary prevention (screening, early diagnosis andtreatment)	treating epilepsy treating hypertension ART and OI prophylaxis	decreases mortality, morbidity >70% seizure free decrease stroke, heart and renal failure decreases mortality/morbidity in HIV
Tertiary prevention (rehabilitation & palliative care)	rehabilitation hospital and community based palliative care	improved quality and independence of life stops/decreases pain and other symptoms