Proposing a National Surveillance for Behavioural Risk Factors of Chronic Diseases in Nigeria using the WHO STEPS Approach

Nigeria has a population of about 140 million (NPC, 2006) and an annual gross domestic product (GDP) per capita of U.S. $1,085; with 5% total expenditure on the health sector. Despite an extensive public-sector–owned health care system, health expenditure is mostly (75%) by private-sector health care providers, with out-of-pocket payments making up the major source (92%) of private financing (www.who.int). In recent years, the federal Ministry of Health as well as at state levels has been heavily burdened with reproductive-health and infectious-disease issues as well as chronic diseases.

The main chronic diseases are heart disease, stroke, diabetes, cancer and some acute respiratory diseases. These are termed non communicable diseases (NCDs) as distinct from infectious diseases. Chronic diseases are particularly significant to the current health profile of human populations. The World Health Organization (WHO) estimates that NCDs are responsible for 47% of the global burden of disease and represent 60% of all deaths globally. Already, 80% of chronic disease deaths are occurring in low and middle income countries.

Recently gathered country-level data from the WHO indicates that NCDs can be regarded as a rising global epidemic. Most chronic diseases are triggered by common, preventable risk factors which are the leading cause of the death and disability burden in all countries, regardless of economic development status. These major risk factors account for around 80% of deaths from heart disease and stroke (Strong and Bonita, 2004). 

Current situation of chronic diseases in Nigeria

Nigeria does not comprehensively address chronic diseases as part of national health agendas maybe because of lack of resources, limited capacity of the health system, and the threat that national-level programs will weaken local systems and compete with other health issues. There has been no systematic surveillance for risk factors of NCDs in Nigeria even though the Federal Ministry of Health has a National Expert Committee on NCD. The last published report was of a national survey in 1997 with most of the data collected from 1990 – 1995. 

Several studies give a shocking picture of chronic diseases among Nigerians;

• Nigeria has the highest number of people approximately 5.1 million, with diabetes and impaired glucose tolerance in Africa. www.idf.org
• The crude prevalence of hypertension has been documented as 11.2% (based on BP threshold of 160/95mmhg) with age adjusted rate being 9.3% (Akinkugbe et al, 1997).
• The annual incidence of stroke in Nigerians has been reported as 26 per 100 000 (Osuntokun, 1994) with more recent reports suggesting an increase.
• According to the World Health Report 2002, cardiovascular disease accounted for 9.2% of total deaths in the African region in 2001, and hypertension, stroke, cardiomyopathy and rheumatic heart disease were most prevalent.
• At present, the estimated annual incidence of cancer is 100,000 and predicted to increase to 500,000 by 2010 with a current cumulative mortality of about 55,000 from the six functional cancer registries (Durosinmi, 2006).

Behavioural risk factors in Nigeria

A chronic disease “risk factor” refers to any feature or exposure of an individual, which increases the likelihood of developing a non-communicable disease. The major (modifiable) behavioural risk factors identified in the World Health Report (WHO, 2002) are: Tobacco use (smoking), harmful alcohol consumption, unhealthy diet, and physical inactivity. Together with raised blood pressure and obesity, the clustering of these risk factors significantly increases the risk of morbidity or mortality from chronic diseases especially heart diseases (Yusuf et al, 1998).

The rationale for including the major four chronic disease risk factors in a national surveillance is that; they have the greatest impact on chronic disease mortality and morbidity, their modification is possible through effective prevention, and measurement of these risk factors has been proven to be valid and can be obtained using appropriate ethical standards (Bonita et al., 2002).

There have been surveys of behavioural risk factors of NCDs in Nigeria done by individual researchers as part of studies on either the prevalence of these risk factors on their own or as background to NCD surveys. Majority of this information has been gathered by the WHO into their Global Infobase on the Nigerian country profile.

Prevalence of major risk factors in Nigeria

National Surveillance

Surveillance involves ongoing collection of data for enhanced decision-making and underpins public health action and health promotion activities. It should be simple, flexible, acceptable and situation-specific. The world Health Assembly “identified three main features of surveillance; the systematic collection of pertinent data, the orderly consolidation and evaluation of these data, and the prompt dissemination of the results to… those who are in a position to take action”.

A prime example of national surveillance is the Centre for Disease Control’s Behavioural Risk Factor Surveillance System (BRFSS). For more than 20 years, BRFSS has helped all 50 U.S. states survey adults using telephone interviews to gather information about a wide range of health-related behaviours. The main focus of these surveys has been behaviours linked with heart disease, cancer, stroke, diabetes, injury and other important health issues. These behaviours include inadequate physical activity, overweight, not using seatbelts, tobacco and alcohol use, and not getting preventive medical care, such as flu shots, pap smears, etc (CDC, 2006).

Proposing a STEPS approach to national surveillance of NCD risk factors in Nigeria

Primary prevention based on comprehensive population-based programmes has been proved to be the most cost-effective approach to contain chronic diseases. The basis of NCD prevention is the identification through surveillance, of the prevalence of these major common risk factors. Such information would be then be used in policy dialogue and decision making for programme planning. Therefore from a primary prevention perspective, surveillance of the major risk factors known to predict chronic diseases is a suitable starting point.

Nigeria, like other developing countries, is undergoing an epidemiological transition which has resulted in a double burden of communicable and chronic diseases as life expectancy is now slowly increasing due partly to a decline in adult mortality. An emerging public health challenge is thus to prevent morbidity and disability due to Non-communicable Diseases (NCDs) and to maintain the health and mobility of the ageing population. To do this, it is essential to obtain information on the disease pattern and exposure to risk factors in the population.

The WHO has recommended surveillance of chronic disease risk factors using the STEPwise approach to Surveillance (STEPS) of risk factors for NCDs (Bonita et al, 2002). This approach uses standardized protocols and instruments to monitor trends within countries and make comparisons between countries. It focuses on the continual collection of data on key risk factors associated with major chronic diseases with the aim of using such information for designing community-based interventions to reduce risk factors in the population.

A prevalence study in rural Indonesia, Nawi et al (2006a) concludes that the implementation of the WHO STEPS approach is feasible and provides a comprehensive picture of the burden of risk factors. Another study which combined Demographic Surveillance Surveys with STEPS to research epidemiological questions on NCDs, report that this can be used as a powerful advocacy tool in public health decision-making for NCD prevention (Nawi et al, 2006b).

The principal reason for setting up and sustaining a system of NCD surveillance in Nigeria will be to supply health workers and policy makers with a dependable tool to plan for prevention strategies in the population. A well-functioning NCD surveillance system should be an integral part of national public health programmes bearing in mind the vision of the ministry of health to “reverse the increasing prevalence of non-communicable diseases…”

This proposed simple and sustainable surveillance system can be used in sentinel sites in many different settings to improve health planning and measure the impact of disease prevention activities. STEPs surveillance will offer a systematic approach to data collection which will be crucial in helping Nigeria monitor and evaluate emerging patterns and trends of NCDs. By using resulting health data, government can formulate policies and programmes to prevent NCDs and to measure the progress, impact, and efficacy of preventive efforts either newly set up or already in operation.

Conclusion

The WHO STEPS approach is based on the concept that surveillance systems require standardized data collection to ensure comparability over time and across locations. It is also sufficiently flexible to be appropriate in a variety of country situations and settings and therefore allows for the development of a comprehensive surveillance system, depending on local needs and resources. At country level, STEPS surveillance will provide better health information and thus better opportunities to improve the health of citizens. STEPS differ from one-off surveys in that it involves commitment to data collection in an ongoing repeated manner. With such repeated surveys, trends in the prevalence of risk factors can be identified (WHO, 2003).

By means of resource commitment from the government and other stakeholders, the national surveillance programme will allow implementation of appropriate health actions that address health inequities. These actions will provide the basic information from which to formulate policy that effectively reduces the burden of disease. Ongoing support from development partners is equally needed to meet the goal of increasing the country’s capacity to undertake the NCD surveillance (Armstrong and Bonita, 2003). However, training of staff for data collection and analysis also has to be emphasized (Reddy et al, 2006).

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References

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