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This training module discusses the importance of surveillance for risk factors for non-communicable diseases (NCDs), the differences between surveillance for communicable diseases and NCD risk factors, and the steps involved in organizing and conducting surveillance. It also covers the role of district surveillance officers in NCD risk factor surveillance.
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Surveillance of the risk factors for non-communicable diseases (NCDs) IDSP training module for state and district surveillance officers Module 14
Learning objectives (1/2) • Describe the importance and the need for surveillance of risk factors for non communicable diseases • Enumerate the differences between surveillance for communicable diseases and risk factors for non communicable diseases • List non communicable disease risk factors under surveillance
Learning objectives (1/2) • List steps involved in organization and conduct of surveillance of risk factors for non communicable diseases • Describe the role of the district surveillance officer in surveillance of risk factors for non communicable diseases
Communicable diseases Sudden onset Single cause Short natural history Short treatment schedule Cure is achieved Single discipline Short follow up Back to normalcy Non-communicable diseases Gradual onset Multiple causes Long natural history Prolonged treatment Care predominates Multidisciplinary Prolonged follow up Quality of life after treatment Communicable versus non-communicable diseases
Projected proportional increase in population > 65 years age, 2000-2030 Italy Japan UK USA China India Chile Mexico 0% 50% 100% 150% 200% 250% Proportion (%) Social Determinants of Health Inequalities, Marmot M, Lancet 2005
Estimated and projected proportion of deaths due to non-communicable diseases, India, 1990-2010 100% 90% 80% 70% Injuries 60% Communicable diseases Proportion (%) 50% 40% Non communicable diseases 30% 20% 10% 0% 1990 2000 2010 Year
1 9 85 2 0 00 2 0 15 M F M F M F A l l c ause s 1 1 58 1 1 65 8 7 9 7 9 0 8 4 6 7 4 5 In f e c t i ous 4 7 8 4 7 6 2 1 5 2 3 9 1 5 2 1 7 5 Ne o p l a s ms 4 3 5 1 8 8 7 4 1 0 8 9 1 C i r c u l at or y 1 4 5 1 2 6 2 5 3 2 0 4 2 9 5 2 3 9 P r e g nan c y 0 2 2 0 1 2 0 1 0 P e ri n ata l 1 6 8 1 3 2 6 0 4 8 4 0 3 0 In j u r y 8 5 6 5 8 2 2 8 8 4 2 9 O th e r 2 3 9 2 9 3 2 8 0 2 8 5 1 6 7 1 7 1 Estimated and projected specific mortality rate per 100,000, by sex, India Epidemiological transition: The concept of evolution from a communicable diseases burden of disease profile to a predominance of non communicable disease Source : World Bank Health Sectorial Priorities Review
Burden of major non-communicable diseases, India, 2004 Stroke Ischemic heart diseases Diabetes
Non communicable disease programmes in India • National cancer control programme • National mental health programme • National blindness control programme • Cardiovascular diseases, stroke and diabetes programme • Trauma and accident programme • Oral health programme • Rehabilitation programme • Geriatric care programme
Existing reporting systems for non communicable diseases in India • Sentinel surveillance systems • National Cancer Registry Programme • Periodic surveys/studies • Census of India • Sample registration systems • National sample surveys • National family health survey • National nutrition monitoring programme
Sources of data collection for non communicable diseases in India • Mortality data • Medical certificates for death • Cause of death surveys • Hospital records • Morbidity data • Registry (Cancer) • Special surveys • Hospital reports • Risk factors • Special surveys • Registries • Cancer (Shift from hospital to community based) • RF/RHD (Jai Vigyan Mission) • Thalasemia (Jai Vigyan Mission)
Implementation of non communicable diseases programmes in countries of the WHO South East Asia region Source:Non-Communicable Diseases in South-East Asia Region, A Profile, WHO, 2002
Prioritizing surveillance for non communicable diseases • Mortality? • Morbidity? • Disability? • Risk factors • The risk factors of today are the diseases of tomorrow
Life course approach for the prevention of non communicable diseases Foetallife Infancy andchildhood Adolescence Adult Life • Established adult risk factors • (behavioural/biological) • Obesity • Lack of activity • Diet • Alcohol, • Smoking • SE potential Development of non communicable diseases • SES • Nutrition • Diseases • Linear growth • Obesity Range of individual risk • SES • Maternal nutritional status & obesity, • Fetal growth Accumulated risk Accumulated risk Age
The causal chain explains the risk factor approach for surveillance of non communicable diseases Behavioral risk factors • Tobacco • Alcohol • Physical inactivity • Nutrition • Physiological risk factors • Body mass index • Blood pressure • Blood glucose • Cholesterol • Disease outcomes • Heart disease • Stroke • Diabetes • Cancer • Respiratory diseases
Rationale of the risk factor approach for non communicable diseases • Non communicable diseases are slowly evolving • Early recognition difficult • A number of risk factors influence one or more non communicable diseases • Risk factors have the greatest impact on non communicable diseases mortality and morbidity • Effective modification of risk factors is possible through primary prevention • Projections may be used to estimate burden • Simple surveillance systems can be used • Measurements standardized and validated and obtainable within ethical limits
The WHO STEPwise approach to surveillance of non-communicable disease risk factors Step 3(Biological) Complexity Step 2(Physical) At each step Core Expanded Optional Step 1(Verbal) Comprehensiveness Sequential approach, step by step
Heterogeneity of non-communicable risk factors in India Kerala High literacy rate, developed Different dietary patterns Metropolitan city, highly urbanized, heterogeneous population Delhi Different body composition Nested population Terrain, relatively underdeveloped Jammu& Kashmir Different habits Nested population Underdeveloped, Tribes and Terrain Nagaland Bihar Illiterate, Poor population Rural, Agricultural, Tribals
Risk factors under surveillance • Tobacco use • Alcohol consumption • Raised blood pressure • Systolic and diastolic • Obesity • Height, weight, body mass index, waist circumference • Diet • Low fruit, high fat, added salt to served food • Physical inactivity • Diabetes mellitus • Fasting plasma glucose • High serum cholesterol
How surveillance for non-communicable diseases differs • Surveillance methods: • Estimating the prevalence of risk factors • Periodic sample surveys in each state every five years • Data generated: • Prevalence of risk factors and unhealthy life style • Time trends • Geographical distribution • Distribution among various populations
Type and frequency of surveys • Periodic sample surveys conducted in states once in five years • 20% of districts surveyed each year • Whole population covered in 5 years • Survey conducted every year in randomly selected districts in a five-year cycle
Organization of the surveys • Practical implementation • Institution with sufficient epidemiological capacity • Best bidders • Coordination and supervision • State directorate of public health • State surveillance unit • District surveillance unit
Target population for survey • Population of 15 years to 64 years. • 10-year age groups • 15-24 • 25-34 • 35-44 • 45-54 • 55-64 • Sampling technique • National Family Health Survey • Cluster sample survey
Sample size • 2500 persons across the 15-64 years age range • 250 participants in each 10-years age group • Two strata • 2500 individuals in urban area • 2500 individuals from rural area
Proposed survey design • Primary sampling unit • Village in case of rural area • Ward (Census Enumeration Block) in case of urban area • Stratification of primary sampling units based on selected variables • House-listing in primary sampling units • Within each selected household, all male and female members aged between 15-64 years are surveyed
Survey instrument • A pre-tested simple questionnaire • Developed on the basis of the WHO (STEPS) • Modified for the Indian context • Already in use for sentinel surveillance for cardiovascular risk factors in 10 selected industrial populations all over India
Information collection • Questionnaire • Measurement • Height • Weight • Blood pressure • Biochemical results • Fasting blood glucose • Serum cholesterol
Step 1: Individual questionnaire (1/2) • Baseline demography • Identification, age, sex, education, occupation • Alcohol consumption • Current drinkers, frequency, quantity • Tobacco (Smoking and smokeless) • Age at initiation, usage, cessation
Step 1: Individual questionnaire (2/2) • Diet, fruits and vegetables • In a typical week, frequency and quantity • Physical activity • At work, transportation and leisure • History of diagnosis and treatment • Hypertension and diabetes
Data collection instrument and analysis • Computer friendly data collection instrument • Easy data entry • Automated data analysis through programme • Generation of information on trends and patterns of non communicable disease risk factors
Findings and their uses • Information generated on non communicable disease risk factors: • Trends • Prevalence in various areas • Distribution in the populations • Uses: • Document the need for prevention and control programmes in the community • Influence policy makers • Guide financial allocation
Ensuring validity • Maximize response fraction • Use valid and reliable instruments • Calibrate instruments • Train staff • Ensure participation of individuals selected • Reduces the probability that those who do attend are unrepresentative of the sample • Engage district surveillance officer and other health personnel • Use existing local public health infrastructure
Role of the district public health laboratories • Conduct tests: • Blood sugar • Cholesterol • Co-ordinate collection, transport and receipt of the samples from the periphery • Plan capacity to carry out analyses quickly • Ensure quality control of biochemical assays • Key factor to ensure useful results
Quality assurance • Common protocol • Standardized training • Standardized survey methods • Monitoring and coordinating set ups • Advisory group and resources • Site visits • Common data management mechanisms • Critical appraisal
Ethical considerations • Questionnaires dealing with lifestyle issues and simple non-invasive measurements • Verbal consent • Blood pressure • Need to clarify whether persons with elevated readings would be followed up and treatment provided • Written consent needed • Collection of blood • Requires prior ethical clearance • Built-in plans for treatment of those with raised levels • Built-in consent form in the questionnaire
Promise to care • Referral, diagnostic and treatment support to persons identified with non communicable disease risk factor will be built into the system • Patients identified with hypertension, diabetes will be referred to the next level for treatment
Timing of the survey • Physiological and cultural considerations • Overnight fasting needed • Start early in the morning (6:00 am) • Finish early in the afternoon (1:00 pm) • Rest of the day • Coding forms • Dealing with the laboratory specimens and other documentation • Preparations for the next day
Follow up action • Coordinated approach for community level interventions • Partnerships • Medical colleges, state health departments, primary health care services and non-governmental organisations • Dissemination of health education material on causes, prevention and incentives to enhance public awareness
High risk and population approaches to prevention Truncate high risk end of exposure distribution (e.g., organize an obesity clinic). Clinical approach to disease prevention Reduce a small amount of risk in a large number of people (e.g., reduce fat a little in fast-food outlets). Lifestyle change plus environmental approach More burden from a large proportion of the population exposed to moderate risk factors than from a small segment exposed to a high risk factor
Intervention strategies • Population based strategy • Prevent non-communicable diseases in the whole population • High-risk strategy • Target people with identified risk factors
Public health interventions Educational interventions Policy interventions Enabling environment (Financial, Social, Physical) Health beliefs and behaviours (Community; Individual) Desired change
Challenges Huge population Many programmes Rural population Emerging epidemics Unemployed youth Burden of non communicable diseases Opportunity Good sample size Different strategies Complex exposures Interventions Trained workforce Feasible intervention Challenges and opportunities
Points to remember (1/3) • The burden of diseases due to non communicable diseases in India became almost equal to that due to communicable diseases in 1990 • The burden of non communicable diseases is increasing while it is declining in developed countries because of surveillance and interventions • The life style related modifiable risk factors for non communicable diseases have been identified and the magnitude of their impact is documented
Points to remember (2/3) • The major non communicable diseases share common, preventable life style risk factors • There is sound evidence that non communicable diseases can be reduced through a package of simple, effective and feasible life style changes • The treatment of non communicable diseases is expensive and therefore the key to control is in its primary prevention
Points to remember (3/3) • Non communicable diseases surveillance is therefore considered an important component of the integrated disease surveillance project • Non communicable diseases surveillance will be done by periodic surveys of selected risk factors and will be independent of regular surveillance for other conditions • The Non communicable disease risk factors to be measured in include: tobacco use, alcohol consumption, high blood pressure, obesity, diet, physical inactivity, fasting plasma glucose and serum cholesterol