In this GBD study, we describe the burden of disease in Sierra Leone from 1990 to 2017. Overall, the burden of disease declined resulting in fewer YLLs. In Sierra Leone, CMNNs continue to be a problem due to the prevalence of endemic disease. CMNNs have a greater effect on male mortality than on female mortality. The most important CMNNs are respiratory infections, neglected tropical diseases and malaria, and maternal and neonatal disease. The burden of NCDs was low compared to CMNNs, a trend which is likely to change as the health system recovers and populations age. Sierra Leone faces a dual burden of disease, with NCDs contributing about 29% while CMNNs account for 65% of YLLs and 6% represent injuries.10–11 The end of the Sierra Leone civil war brought the government, international partners, stakeholders and civil society together to start reconstructing the health system. The recovering health system and implementation of health policy interventions has resulted in the decline of YLLs due to CMNNs and NCDs. Our study shows that Sierra Leone has made progress in population health outcomes despite multiple drawbacks.
The Sierra Leone civil war took place from 1991 to 2002, lasted 11 years and left more than fifty thousand people dead. The civil war would have contributed to burden of disease in several ways, including an increase in injuries. Mortality rates due to NCDs peaked between 1990 and 1994, reflecting the potential impact of the civil war. The mortality rates of men due to NCDs at this time were also markedly higher than the mortality rates for women. Mortality rates have declined consistently after the end of the civil war, suggesting efforts to rebuild the health system. Men and women’s mortality rates equalised after 2010. In 2014, mortality increased slightly due to the Ebola outbreak which lasted for two years.
Sierra Leone had to address a greater burden of CMNNs than NCDs from 1990–2017. The burden of CMNNs is high when compared to other countries.3 Malaria and neglected tropical diseases, respiratory infections contribute to significantly to YLLs and disability.3 The burden of CMNNs peaked in 1990 and 1992 and can be attributed to persistent endemic malaria.12 Sierra Leone health services treat approximately 2,240,000 outpatients annually for malaria and almost half of these are children under the age of five years.13–14 Malaria mortality was estimated at approximately 4.4% of pregnant women and 17% of children. Malaria contributes to 40% of hospitalised morbidity in all ages and 37% of children under five. 13 In 2004, Sierra Leone launched their first National Malaria Strategic Plan (2004–2008), which was funded by the Global fund. 13
In Sierra Leone, maternal and neonatal disorders remained high from 1990 to 2017. In Sierra Leone, children under five years suffer high mortality rates with 120 deaths per 1000 children. Maternal deaths are amongst the highest in the world at 1360 deaths per 100000 live births in 2015, which far exceeds the MDG targets of 450 deaths per 100,000 births.11,15 In this study, the burden of maternal and neonatal disorders dropped from 21833.31 per 100,000 in 1990 to 8 889.03 in 2017.3 In 2010, the Sierra Leone government launched the Free Health Initiative to reduce mortality and morbidity due maternal and neonatal disorders.11
Aside from malaria and maternal and neonatal mortality, respiratory diseases and tuberculosis, enteric infections and HIV also contribute to YLLs in Sierra Leone. In 1990, the German Leprosy Relief Association assisted the Ministry of Health and Sanitation to establish the National Leprosy and Tuberculosis Control Programme to monitor the surveillance of tuberculosis control activities.16 In this study, respiratory disease YLLs decreased from 24255 fatalities per 100,000 population in 1990 to 7330 deaths per 100,000 population in 1997. Sierra Leone continues to have one of the highest tuberculosis burdens in the world despite the fact that treatment is free and readily available. 17Sierra Leone opened its first drug-resistant tuberculosis treatment centre at Lakka Government Hospital in 2017. Nonetheless, new recommendations, constant monitoring and surveillance of the National Tuberculosis Program remain necessary.17
The frequency of enteric infections has dropped from 17210 deaths per 100,000 persons in 1990 to 4558 deaths per 100,000 persons in 2017.3 Enteric diseases are most prevalent in children under the age of five and account for around 12% of all child deaths in Sierra Leone.18 Sierra Leone added the rotavirus vaccine to its immunization schedule to combat diarrhoeal infections on March 28, 2014, in an effort to address this issue.18
The burden of HIV/AIDS and sexually transmitted infections (STIs) increased from 1101 to 2124 cases per 100,000 population.3 In 2013 and 2014, commercial sex workers were responsible for 40% of newly infected HIV patients .19 The Sierra Leone government is stepping up efforts to test, prevent, treat and increase awareness with the support of the WHO, Global Fund and many other partners. The Sierra Leone government has also implemented a national HIV AIDS strategic plan 2016–2020, including programmes such as Prevention of Mother to Child Transmission.17
As a developing country with a relatively young population, the risk factors associated with YLLs due to CMNNs are also linked to the health and wellbeing of younger age groups. The most important risk factors for CMMN YLLs were environmental risk factors including child and maternal nutrition, unsafe water and sanitation and exposure to air pollution. Less important risk factors included lifestyle risk factors such as alcohol and tobacco use, drug use and intimate partner violence. In Sierra Leone, environmental risk factors are being addressed on various fronts. In 2012, the presidency committed to the UNICEF Scaling Up Nutrition Movement and adopted a Food and Nutrition Security policy to secure the nutritional well-being of infants and women. Unsafe water and sanitation are other environmental risk factors being considered by the WHO and UNICEF who are trying to improve water and sanitation services by conducting risk assessments and improving health facilities that were destroyed during the civil war.
Additionally, lifestyle risk factors such as HIV/Aids and sexually transmitted diseases, as well as respiratory illnesses, contribute to CMMNs. In Sierra Leone, alcohol consumption is ranked in the fifth place, while cigarette consumption is placed sixth as risk factors for YLLs. These lifestyle risk variables were associated with a relatively small number of deaths; for example, cigarette smoking was associated with 5% of YLLs.3 Although the number of YLLs connected with these risk factors is still small, it is increasing and requires monitoring by local organizations. Sierra Leone signed the WHO Framework Convention on Tobacco Control in May 2009, with the objective of reducing tobacco consumption, and the Ministry of Health and Sanitation adopted a National Tobacco Control Strategic Plan in 2012.17
In this study, CMNN contributed significantly more to YLLs than NCDs from 1990–2017. NCDs are expected to grow by 25% globally by 2030.20 Sierra Leone was also predicted to have an increase.20–22 In 2008, the WHO estimated that NCDs accounted for 18% of fatalities in Sierra Leone, followed by cardiovascular disease at 7%, cancer at 3%, diabetes at 1%, and chronic respiratory illness at 2%. 21 In 2012, mortality from NCDs increased to 26%. Sierra Leone's government developed its first strategic plan and policy for NCDs in 2013, in response to the World Health Organization's global status report on NCDs. Sierra Leone's strategic plan, which ran from 2013 to 2017, attempted to mitigate the burden of NCDs such as cardiovascular disease, chronic lung disease, diabetes mellitus, obesity, cancer, sickle cell disease, mental disorders, and epilepsy.21,23 By 2014, the burden of NCDs had reduced across all age groups and sexes, with men accounting for 323 deaths per 100,000 and women accounting for 321 deaths per 100,000.22
The burden of NCDs remained relatively constant between 2005 and 2017. In our study, most YLLs due to NCDs can be attributed to cardiovascular related diseases and neoplasms.3 Cardiovascular disease contributed to approximately 9% of NCD deaths (this study) and has been among the top ten causes of YLLs since 1990.21 There is evidence that NCDs are increasing. In 1993, 68% of hospitalisations at Freetown hospital were admitted due stroke.21 In 1994, 25% of the population above 50 years of age were estimated to be hypertensive.21 A review of death certificates issued between 1983 and 1992, showed an increase in deaths related to hypertension in Sierra Leone.21 There is little information on the prevalence of cancer in Sierra Leone, even though our study reported that neoplasms were among the top ten causes of mortality.21 In Sierra Leone, recording and reporting of data on NCDs remains inconsistent even though there is a ministerial department responsible for NCDs.21
Sierra Leone suffered an Ebola outbreak in 2014 and 2015, which led to inadequate quality surveillance data on the incidences, cases and deaths of NCDs.24 The Ebola outbreak occurred when the government was transitioning from hospital care for NCDs to management, treatment and care in primary health care facilities.24 Following the Ebola outbreak, significant reporting systems focusing on morbidity and risk factors for NCDs were put in place. Although policies are being developed by the government, there seems to be little funding for treating and controlling NCDs.24 The most dominant risk factors associated with NCDs include high blood pressure, dietary risks, high fasting plasma glucose, high body mass index and the use of alcohol and tobacco (this study). In Sierra Leone, DALYs due to high blood pressure have also increased (18%) from 2007 to 2017.
Dietary risks are also associated with YLLs due to NCDs in Sierra Leone. A nutritional survey done in 2014 revealed that more than 25% of children younger than five years old had stunted growth.21,24 Glucose has recently become an important risk factor NCD associated YLLs and is growing in importance. High fasting plasma glucose is an indicator of diabetes mellitus. The prevalence of diabetes in Sierra Leone has also increased from 2.4% in 1997 to 7% in 2014. 21
Tobacco use is an important risk factor of NCDs, including cardiovascular disease, respiratory diseases and lung cancers.21 In Sierra Leone, 14.3% of men and 1.4% of women, comprising 34% of people, smoke more than 10 cigarettes a day.21 Consuming alcohol is an important risk factor for cardiovascular disease. In 2005, 6.5% of adults older than 15 years consumed alcohol. In 2014, 17% of adults between the ages of 25 and 64 years old were estimated to consume alcohol.21 Added to problems of hypertension, glucose and substance abuse is the fact that Sierra Leoneans engage in low to moderate physical activity. The importance of high body mass index as a risk factor jumped from 9th in 1990 to 5th place in 2017.3 The burden of NCDs remains low compared to CMNNs, which may contribute to few resources being allocated to preventing NCDs at this time.