CHAPTER ONE

GENERAL INTRODUTION

1.1 The Research Context

The rate of prevalence of non-infectious diseases has been steadily growing globally and most especially in the developing countries in the past few decades. These are conditions which affect individuals over an extended period (years, decades or even an entire lifetime) and for which there is no known causative agents that are transmitted from one individual to another (Daar et al., 2014). The term is used to apply to a variety of conditions including cardiovascular diseases, diabetes mellitus, cancer, chronic respiratory diseases, musculoskeletal disorders, and other conditions, which come about as a result of genetic or environmental factors other than pathogenic life forms. These diseases are equally known as non-communicable diseases (NCDs), chronic or long-lasting diseases or diseases of affluence or lifestyle. The terms non-infectious diseases and NCDs will be interchangeably used throughout the study.

Non-Communicable Diseases are amongst the leading causes of death and disabilities in the world and are also a major health challenges of the 21^st century, as they result in high mortality rates (WHO, 2010), almost all countries are experiencing an increase in the NCDs which affect all age groups, both poor and rich people, men and women (Bonita, 2005). NCDs represent 43% of the global burden of diseases and deaths resulting from them are predicted to rise by 60% to 70% of all deaths, based on available trends by 2020 (Murray, 2005). Current global trends show that NCDs constitute a significant percentage of the overall disease burden. In 1990, communicable disease, nutritional, and neonatal conditions accounted for 47% of the global burden of diseases (GBD) with NCDs responsible for 43% of disease burden and the remaining 10% attributable to injuries (Murray, 2003). By 2010, the global NCD burden had increased to 54%, with communicable disease, neonatal, nutritional, and maternal conditions reducing to 35% of disease burden (Murray, 2012). This trend has been consistent in subsequent burden of disease analysis, with the burden of several communicable diseases falling while that of NCDs increased as shown in the 2013 (Naghavi, 2015) and 2016 (Vos, 2017) GBD studies. In addition, GBD analyses also revealed that a significant proportion of global disabilities are attributed to NCDs as years lived with disability estimates have increased with rising NCD trends, from 537.6 million in 1990 to 764.8 million in 2013 (Vos et al., 2017).

A significant portion of global mortality stems from NCDs. This leading NCDs were responsible for about 63% of global deaths in 2008 (36million), cardiovascular diseases (CVDs) accounting for 48% of NCD deaths and chronic respiratory diseases, cancers and diabetes which are important contributors (Naik, 2015); (Marquez, 2013) Currently, it is estimated that NCDs cause 41 million global deaths annually, which corresponds to 71% of all deaths each year (WHO, 2018a). The leading cause of mortality include CVDs (17.9 million), with hypertensive heart disease particularly prominent (WHO, 2016a), cancers (9.0 million), respiratory diseases (3.9 million) and diabetes (1.6 million) (WHO, 2018a).

There have been dramatic changes in global health over the second half of the twentieth century. Progress in public health has contributed to an increase in global life expectancy at birth from 48years between 1950 and 1955, to 68years between 2005 and 2010 (U.N, 2012). The rise in life expectancy has occurred alongside a transition to new disease patterns, especially in low- and middle-income countries. There is a marked change from highly fatal infectious diseases in children and epidemics affecting both infants and adults (such as HIV/AIDS, diarrheal diseases and malaria), to predominantly degenerative, non-communicable conditions in adults (Omran, 2005).

Modernization, globalization, and urbanization have been implicated in the shift from infectious to non-infectious diseases. Improvements in social, economic, and environmental conditions mean that circumstances which were previously conducive for infectious diseases have been replaced by good sanitation, improved medical care, and a generally better standard of living (Yusuf, 2002). This ultimately leads to a reduced risk of acquiring infectious diseases and increased risk of experiencing NCDs as people now grow into the middle and older ages where their risk of dying from degenerative diseases increases (Popkin, 2004). This shift in the pattern of disease arising from socio-economic advancement has been referred to as the epidemiological transition, a phenomenon that is sweeping across many countries (Omran, 2005).

With growing populations in Lower- and Middle-Income countries (LMICs), global statistics show that increasing numbers of NCD deaths occur in these countries (Naik & Kaneda, 2015; Marquez & Farrington, 2013). According to the WHO Global Status Report on NCDs 2014 (WHO, 2014), although NCDs were responsible for 68% of the 56 million global deaths in 2012, close to three-quarter of these were in LMICs. The WHO estimates that by 2020, NCDs will account for 80% of the global burden disease, causing seven out of every 10 deaths in developing countries, about half of the premature deaths are under the age of 70 years (Mathers, 2005). This is hardly surprising considering that the incidence of the leading NCDs such as diabetes has risen faster in LMICs than in high-income countries (HICs) in the last decade (WHO, 2016a). Research shows that the impact of premature mortality from NCDs has been felt severely in LMICs, across several regions: Latin America and the Caribbean (Perel et al., 2006), Asia (Naik & Kaneda, 2015), the pacific (Hou et al., 2016), and Africa (Marquez & Farrington, 2013; Naik & Kaneda, 2016).

Although the NCD situation is alarming in LMICs around the world, the African situation is unusual as 80% of countries in this region are in the LMIC category (Nyaaba et al., 2017). The GBD study of 2010 reported a remarkable rise in NCD burden in Africa and confirmed recent discussions on the epidemiological transition from infectious diseases to NCDs, underscoring the ‘double-burden’ or ‘double jeopardy’ of communicable and NCDs (Agyie-Mensah & Aikins, 2014, Aikins et al., 2015). Available data show the African region experienced over 2 million NCD deaths in 2010 (Naghavi et al., 2015). In countries such as Seychelles and Mauritius and in population groups over the age of 45 years, NCDs have already replaced communicable diseases as the leading cause of mortality (Marquez and Farrington, 2013). In North Africa, NCDs account for over three-quarters of all mortalities and nearly half the population of sub-Saharan Africa already suffers Hypertension (HTN) (Naik and Kaneda, 2015). In general, HTN and Diabetes Mellitus (DM) are among the leading NCDs in Africa.

According to the WHO African Regional Consultation Meeting on Global Strategy on diet, physical activity and health (Harare, 2003), ‘the risk for non-communicable diseases is gaining importance in Africa with a prevalence of high blood pressure estimated at 30-40% although prevalence data from national surveys are generally inadequate’.

 Cameroon like one of those LMICs in Africa, with most of the people in the country living below 1US dollar per day, is also experiencing an increase in morbidity and mortality as a result of this NCDs. According to the 2014 NCD profile report for Cameroon, NCDs accounted for 239,000 deaths estimated 31% of total deaths that same year were NCD-related (WHO, 2014). This report also states that there is a 20% probability of dying between the ages of 30 and 70 years from the 4 main NCDs in Cameroon (diabetes, cancer, cardiovascular diseases and chronic respiratory diseases) which could worsen with an increasing population aged 50 or more, and an increase in obesity, because of urbanization and social mobility (Echouffo-Tchegui and Kegne, 2012).

The epidemiological profile of the country is marked by a predominance of communicable diseases, including HIV/AIDS, malaria, and tuberculosis, which represent 23.66% of the overall disease burden, along with a remarkable increase in mortality due to non-communicable diseases, including cardiovascular diseases, cancers, diabetes, mental illness, and trauma due to road accidents.

Cameroon is a country where the main foods of consumption are very rich in starch, oils, and sugars, and most people are increasingly exposed to contemporary and unhealthy diets leading to increase in obesity rates, which is rapidly becoming a health issue in Cameroon. This is encouraged by the fact that being obsessed is perceived by some people to be a sign of good living because it confers respect and influence (Kiawi et al., 2006). Also, in a qualitative survey conducted by Dapi et al., (2010), among Cameroonian adolescents, more and more are strongly having preference for sweetened foods, with an increase transition over time from traditional diet in rural areas to a more westernized diet. The adoption of unhealthy lifestyle behaviors that are risk factors for NCDs has been emerging not only in urban areas but also in the rural areas as well, health beliefs, lay perceptions, and health behavior have strongly contributed to the occurrence of chronic NCDs. Misconceptions indicated by popular health beliefs, have caused many Cameroonians to fail in taking appropriate actions for the prevention and control of NCDs such as diabetes and CVD and their risk factors (Kiawi et al., 2006; Awah et al., 2007).

Public health attention in the North West region of Cameroon has shifted towards the treatment and prevention of communicable diseases with little attention given to NCDs such as cancers, diabetes, chronic respiratory diseases, and injuries over the past decade. However, the true epidemiological burden of these NCDs in the region are relatively unknown as there is little or incomplete data available, Enow-Orock et al., (2012).

1.2 Statement of the Research Problem     

It becomes more appalling as the populations in Bamenda, are victims of both a high prevalence of non- communicable diseases and communicable diseases to an extent, with much of its health resources invested in the fight against diseases like HIV/AIDS, Tuberculosis, Poliomyelitis, and on the other hand there is a rising need for investment on managing non-communicable diseases since managing complications arising from these diseases have been shown to be costly , the greatest challenges plaguing the public health sector includes; low turnout at screening centers, vast health inequality as far as diagnosis, management, and referral of NCD cases in most health units are concerned; insufficient efforts towards screening and early diagnosis as well as patient agenda setting and follow up.

Most patients seen in the hospitals are already at an advanced stage of infection with NCDs, while many NCD cases remain undiagnosed in the communities, other morbidity and mortality cases result from ignorance and others from negligence. These problems greatly illustrate the reality of inadequate commitment to responding to the plight of people living already with NCDs and those at risk of contracting the disease. In a study conducted by (James et al., 2010), it has been revealed that patients now undergo dialysis just twice weekly due to the lack of resources as opposed to thrice weekly, stipulated as the ideal. This is a clear indication that, with the rise in the prevalence of chronic kidney disease, the future might not be a very good one for the populations if measures are not put in place to arrest this situation.

Bamenda, the chief town of the North West Region has grown rapidly over the past few years and the trend is projected to continue rising at a geometric rate. According to the National census data for 2005, Bamenda recorded its highest increase from the years 2002-2005 with a population increase of 124,170, and a growth rate of 15.07% and presently its population is estimated at 553000 according to the United Nations World prospects for 2021 population statistics. The town is currently undergoing a socio-economic transition characterized by improving standards of living, rapid (mostly unplanned) urbanization and westernization of lifestyles, including increased tobacco use, unhealthy diets, insufficient physical activity and the harmful use of alcohol, which are accompanied by changes in the distribution and patterns of disease, with NCDs contributing a significant share of the public health burden of disease, alongside unfinished agenda of infectious diseases.

In a study conducted by Mapa-Tassou et al., (2017), and its observations deduced from empirical evidence or projections, most studies carried out on NCDs are reports or hospital- based studies which alone cannot adequately reflect the total mortality due to NCDs in the general population, with very little done on population-based studies as such, an accurate assessment of the current magnitude and trends is difficult to perform in the absence of population-based data. The purpose of this study is to acquire more data from the population to compliment the already existing studies from hospitals, reports to objectively evaluate the exact burden of NCDs in terms of morbidity and mortality over time and space in Bamenda. The finding therefore will provide an analysis on how the health sector has been used to improve on the population’s health within study area and how it can be upgraded upon for better services.

1.3 Research questions

The main research question is, How and why have non-infectious diseases increased in the Bamenda municipality? The specific research questions are guided by:

1. What are the dominant NCDs in Bamenda and how have they evolved over time?
2. Is there an observable pattern in the prevalence of non-infectious diseases in Bamenda?
3. What are the determinants of the prevalence of non-infectious diseases in the municipality?
4. How successful are the public health measures initiated to reduce the risks of non-infectious diseases in the population of Bamenda?

1.4 Research objectives

The main research objective is, To assess the time and space evolution of non-infectious diseases in the Bamenda municipality. The specific research objectives are guided by:

1. To identify the dominant non-infectious diseases in Bamenda and their evolution over time.
2. To investigate the observable patterns in the time and space prevalence of non-infectious diseases in the municipality.
3. To examine the determinants of the prevalence of non-infectious diseases in the municipality.
4. To evaluate the measures instituted by the public health to reduce the risks of non-infectious diseases in the population of Bamenda.