introduction to non-communicable diseases ahmed mandil, prof of epidemiology ksu college of medicine

Introduction to Non-Communicable Diseases

Ahmed Mandil, Prof of Epidemiology

KSU College of Medicine

Headlines Definitions Examples Magnitude of the Problem Risk Factors Sources of Data Prevention & Control Challenges Injury epidemiology & prevention

May 8, 2023 2NCD Epi

Definitions (I) Chronic health-related state: a state which lasts for a long

time, usually more than 3 months Chronic exposure:prolonged (long term), usually of low

intensity. Chronic diseases: those diseases that have uncertain

etiology, multiple risk factors, a prolonged course, do not resolve spontaneously, and for which a complete cure is rarely achieved.

Non-communicable diseases (NCD): a miscellaneous group of health-related conditions, usually not communicated through infective pathogens, and may cause impairment, disability, handicap or even premature death.


Defintions (II) Risk factor: an aspect of personal behavior / life-style, an

environmental exposure, an inborn / inherited characteristic, which on the basis of epidemiologic evidence, is known to be associated with health-related condition(s) considered to important to prevent.

Modifiable risk factor: a determinant that can be modified by intervention, thereby reducing the probability of occurrence of disease or other specified outcomes.

Latent period: delay between exposure to a disease-causing agent and the appearance of manifestations of the disease. E.g. after exposure to ionizing radiation, there is a latent period of 5 years, on the average, before development of leukemia, and > 20 years before development of certain other malignancies.


Definitions (III): Exceptional NCD

Some NCD were recently proven to be of infectious origin, e.g. peptic ulcer (Helicobacter pylori), liver carcinoma (HCV), cancer cervix (Human Papilloma Virus), leukemia (oncogenic viruses), etc.

The term chronic may not apply to conditions as: angina pectoris, Acute Myocardial Infarction (AMI), anxiety, acute depression

Some infectious diseases are chronic: e.g. T.B., HIV / AIDS


NCD Examples (I) Congenital anomalies Malnutrition (pediatric, geriatric) Endocrinal / metabolic disorders (e.g. diabetes,

gout) Cardiovascular diseases (e.g. hypertension;

atherosclerosis; ischemic heart disease [IHD]: angina, myocardial infarction) .

Locomotor system problems: e.g. arthritis (acute, chronic)

Chronic respiratory conditions (e.g. bronchial asthma)May 8, 2023 6NCD Epi

NCD Examples (II) Occupational-related conditions (e.g.

pneumoconiosis) Neoplasms (benign / malignant; childhood /

adult) Injuries (intentional / non-intentional) Sensory loss (e.g. deafness, blindness) Diseases of senescence (degenerative

diseases) Psychiatric disorders (neuroses, psychoses)


Magnitude of the Problem (I)

NCD are considered the leading causes of death and disability on a global scale, and appear to have been so, for at least the last two decades of the 20th century. Disease rates (morbidity and mortality) from these conditions are accelerating globally, advancing across regions and social classes, with special burden in less developed nations.


Magnitude of the Problem (II)

Among the many NCDs that contribute importantly to the global burden of disease, disability and death, cardiovascular disease (CVD), cancer, diabetes and chronic respiratory diseases are four of the most prominent. These four conditions are linked by common lifestyle determinants such as imbalanced diet, physical inactivity and tobacco consumption. They together contribute to 50% of global mortality. NCD are expected to account for an increasing share of disease burden, rising globally from 43% in 1998 to 73% by 2020. The expected increase is likely to be particularly rapid in less developed nations.


The Regional Situation The WHO Region for the Eastern

Mediterranean, NCD account for 52% of all deaths and 47% of the disease burden in EMR during the year 2005

This burden is likely to rise to 60% in the year 2020

The conventional risk factors may explain 75% of such NCD


Cardiovascular

Chronic RespiratoryDisease Type 2

DiabetesCancer

Chronic Diseases result in percent of deaths

452EMR Adult Population


STEPwise data from some EM countries

Country Year of field work

Diabetes %

Hypertension %

Overweight & Obesity %

Iraq 2006 10.4 40.4 66.9

Jordan 2007 16 25.5 67.4

Saudi Arabia 2005 17.9 26

Syrian Arab Republic

2003 19.8 28.8 56.3

Kuwait 2005 16.7 24.6 81.2

Egypt 2005 16.5 33.4 76.4

Sudan 2005 19.2 23.6 53.9


Risk Factors Aging of the population Use of motor vehicles (automobiles) Life-style changes

Poor / unbalanced / unhealthy nutrition Tobacco consumption / addiction Physical inactivity Harmful use of alcohol consumption

Obesity Other social and behavioral factors.


NCD RISK FACTORS, EMR Tobacco use 16-65% Hypertension 12-35% Diabetes 7-25% Overweight-obesity 40-70% Dyslipidemia 30-70% Physical Inactivity 80-90%


Sources of data on NCD Data Mortality statistics Hospital records (especially discharge) Disease registries (e.g. cancer / diabetes /

hypertension registries) Interview surveys Occupational medical records Sickness and disability insurance statistics Drugs' dispensing statistics (prescribed, over-

the-counter)


NCD Prevention and control (I)

Goals: To reduce disease incidence To prevent / delay onset of disability To alleviate severity of disease To prolong the individuals’ life

(Inshaa-Allah)


NCD Prevention and control (II)

Important issues: One of the most important objectives of NCD control is the

change of the public's perception of NCD from one of "inevitability" to that of "preventability".

NCD control is based on avoidance of the most important risk factors (e.g. tobacco addiction, physical inactivity, poor nutrition), all of which are behavioral factors, often difficult to change.

Healthy behaviors should be promoted early on in life through comprehensive school health education and efforts to change behavior in children and young people.


NCD Prevention and control: (III) Primary prevention

Directed at susceptible persons, before they develop a certain NCD, thus aims at reducing incidence.

Needs establishment of risk factors, before-hand (community-specific).

Examples: Tobacco prevention programs, promotion of physical activity, dietary recommendations (for balanced diets suitable for age, gender, physical activities, growth & development, weather, community).


NCD Prevention and control:(IV): Secondary prevention

Directed at asymptomatic individuals, but have developed biological changes resulting from the disease, thus aims at reducing prevalence.

Goal: early detection, management, avoiding / reducing undesirable consequences / complications.

Examples: screening programs (e.g. for diabetes, hypertension, cancer), recommended when: natural history permits early detection, available screening tests for early detection, acceptable to the population at risk; effective management regimens


NCD Prevention and control:(V): Tertiary prevention

Tertiary prevention: Directed at preventing disability in people who have

symptomatic disease, thus aims at trying to improve quality of life.

Goal: prevention of progression of a disease and its complications; provision of rehabilitation.

Examples: screening for / management of diabetic complications (e.g. retinopathy); orthopedic prosthesis (e.g. for fracture-hip); physiotherapy (e.g. for cardiovascular stroke / paralysis / sports injuries’ victims)


NCD Prevention and control:(VI): Role of Different Agencies

Public (governmental) agencies: fund/conduct research; establish standards; provide financing for medical care; deliver medical services to the poor; monitor health status of the population.

Voluntary (non-governmental): fund research; provide public and professional education; stimulate social and legislative changes; create visibility for prevention and control through their large cadre of volunteers.

Medical care sector: delivers services; provides preventive medicine through primary care; establishes professional guidelines that improve the quality of life.


NCD Prevention and control: (VII) Challenges - 1

Information on NCD (need for establishment /effectiveness of surveillance activities).

Applied research Choosing / maintaining healthy

behaviors Social and political policies (laws,

regulations)


NCD Prevention and control: (VII) Challenges - 2

Communication of health risk (proper health promotion)

High risk and population-based approaches Cost of health care Access to health-care services (cooperation

between public / private systems, multi-sectoral cooperation, health insurance initiatives).


References 11. Last J. A dictionary of epidemiology. 5th

Edition. Oxford, New York, Toronto: Oxford University Press, 2008.

2. Remington PL, Brownson RC, Wegner MV. Chronic disease epidemiology and control. 3rd Edition. Washington, D.C.: American Public Health Association, 2010.

3. WHO. 2008-2013 Action Plan for the Global Strategy for the Prevention and Control of Non-communicable Diseases. Geneva: WHO, 2008


References 24. Fadhil I. Diabetes and other non-

communicable diseases: An Eastern Mediterranean Perspective. WHO, 2009

5. Kuh D, Ben Shlomo Y. A life course approach to chronic disease epidemiology. Oxford, New York, Toronto: Oxford University Press, 1997.

6. Newcomer RJ, Benjamin AE. Indicators of chronic health conditions. Baltimore, London: The Johns Hopkins University Press, 1997.


introduction to non-communicable diseases ahmed mandil, prof of epidemiology ksu college of medicine

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