Fractures in sub-Saharan Africa: epidemiology, economic impact and ethnography (Fractures-E3): study protocol

Background: The population of older adults is growing in sub-Saharan Africa. Ageing exponentially increases fragility fracture risk. Of all global regions, Africa is projected to observe the greatest increase in fragility fractures. Fractures cause pain, disability and sometimes death, and management is expensive, often requiring complex healthcare delivery. For countries to plan future healthcare services, understanding is needed of fracture epidemiology, associated health service costs and the currently available healthcare resources. Methods: The Fractures-E3 5-year mixed-methods research programme will investigate the epidemiology, economic impact, and treatment provision for fracture and wider musculoskeletal health in The Gambia, South Africa and Zimbabwe. These three countries are diverse in their geography, degree of urbanisation, maturity of health service infrastructure, and health profiles. The programme comprises five study types: (i) population-based cross-sectional studies to determine vertebral fracture prevalence. Secondary outcomes will include osteoarthritis and sarcopenia. Age- and sex-stratified household sampling will recruit 5030 adults aged 40 years and older; (ii) prospective cohort studies in adults aged 40 years and older will determine hip fracture incidence, associated risk factors, and outcomes over one year (e.g. mortality, disability, health-related quality of life); (iii) economic studies of direct health costs of hip fracture with projection modelling of future national health costs and cost-effectiveness analyses of different hip fracture care pathways; (iv) national surveys of hip fracture services (including traditional bonesetters in The Gambia); and (v) ethnographic studies of hip fracture care provision and experiences will understand fracture service pathways. Conclusions: Greater understanding of current and expected fracture burdens, fracture risk factors, and existing fracture care provision, is intended to inform national clinical guidelines, health service policy and planning and future health service development in sub-Saharan Africa.</ns4:p

Disparities in fragility fracture and osteoporosis care in Africa.

Over coming decades, Africa is predicted to experience the greatest rise in the number of older people, who, in this region, spend longer living with disability and dependence than do those in high-income settings, impacting individuals, families, communities, and healthcare systems in some of the most resource-poor countries. As well as shifting demographics, rapid urbanisation, double and triple burdens of malnutrition, changing physical activity patterns, workplace environments, and climates change contribute to the growing prevalence of non-communicable diseases 1. NCDs include cardiometabolic and musculoskeletal diseases, which often coexist as multimorbidity, along with communicable diseases such as HIV – an emerging chronic disease of ageing. Growing evidence shows HIV and its treatment are important risk factors for fracture2. In the Global Burden of Disease study, fragility fractures and osteoporosis (defined as low bone mineral density (BMD) and structural deterioration of bone) contribute to ‘other’ musculoskeletal disorders, yet their important contribution to the rising prevalence of injury- and fracture-related disability, morbidity and mortality is increasingly recognised 3. To date, lack of awareness and hence healthcare prioritisation in Africa, plus a high income country-led focus on specialist techniques to assess BMD (that are unavailable across much of Africa), has likely led to wide-spread under-reporting of morbidity (e.g., disability) and mortality associated with fragility fractures, inevitably creating inequity in fracture prevention and care provision 3. Fractures of the proximal femur (hip) present a particular challenge to functional ability and survival. Hip fracture incidence is projected to double in South Africa between 2020-2050; a rise which will be seen across West, East and Southern African countries as populations continue to age and transition economically 4 5. In Black South African women and men, fracture outcomes are poorer, with much higher morbidity and mortality than is seen in other countries 6. Harmonisation of cohorts across South Africa, The Gambia, and Zimbabwe, confirmed that osteoporosis and osteopenia are just as common in ageing Black African populations, as their similarly aged US counterparts 1. Healthcare systems, increasingly managing age-related multimorbidity, need to adapt to manage osteoporosis and prevent fragility fractures, for example HIV services managing post-menopausal women should be routinely assessing fracture risk. Without such changes, exacerbating health inequities will continue to grow for ageing populations in these settings. Solutions lie in improving clinical awareness, primary care and specialist training, and expansion in access to potentially innovative diagnostic, treatment and rehabilitation services. Traditionally an osteoporosis diagnosis requires a dual energy X-ray absorptiometry (DXA) scan confirming a BMD T-Score ≤−2.5 (using internationally defined thresholds for diagnosis 1,7). Furthermore, DXA scanners are expensive, require specialist support, reliable electricity supply, and are very few (just three in Zimbabwe; population 15.2 million). Where they are available, costs can prove prohibitive to public healthcare users 8. Additionally, as most people who sustain a fragility fracture have a femoral neck BMD T-Score greater than −2.5, i.e., not in the osteoporotic range consideration of the many clinical risk factors besides BMD, for fragility fracture risk, is key. Widespread DXA scanning provision is not practical in resource-constrained public healthcare settings; hence, validation of methods for non-specialist fracture risk assessment should be a priority; options including FRAX®, Garvan and the vertebral fracture risk assessment calculator (VFRAC). Validation will necessitate collection of robust epidemiological data for fracture prevalence and incidence in different populations across Africa. Furthermore, evidence is lacking for the role of additional context-specific clinical risk factors such as HIV infection, which are likely to be important beyond age, BMD, prior fracture and alcohol intake (for men) 9. There will be few data regarding parental fracture in many populations due to historically low life expectancy. Further, research is needed to validate these new fracture risk assessment tools in African populations.A further inequality stems from differences in provision within public and private health care services where access to medicines, used commonly in high income countries for primary and secondary fracture prevention, is most often only possible in private healthcare systems. This largely reflects lack of prioritisation of osteoporosis medicines, as being ‘essential’, by the WHO. Where private healthcare plans exist in South Africa, osteoporosis is not considered a primary medical benefit, hence there is no incentive to assess and treat fracture risk, though those with more comprehensive medical insurance are reimbursed in the case of severe osteopenia, osteoporosis and fracture8. Medical pluralism is also common, particularly in West Africa where traditional bone setters are usually the first point-of-contact on a complex care pathway, which can result in treatment delays. Equitable access to affordable osteoporosis and fracture treatment should be a priority for health care providers and policy makers. The ultimate clinical manifestation of osteoporosis is a fragility fracture. Much of the available literature in Africa has been under powered to estimate fracture prevalence or incidence. Except for South Africa, there remains a paucity of robust epidemiological data to evidence the rise in fragility fractures and to determine context-specific clinical risk factors. Notably, of 131 fracture liaison services surveyed globally in 2020, only one was operational (in South Africa) across Western, Eastern and Southern Africa 10.In conclusion, ageing populations in Africa do not have equitable access to diagnostic and treatment options to reduce future fragility fracture risk and subsequent disability. Given the predicted exponential rise in demand placed by osteoporosis and fragility fractures on already stretched healthcare systems, this must be given attention. Awareness is certainly increasing, with recognition of the importance of appropriate diagnostic and management pathways. It will be important to ensure that communities and stakeholders are fully consulted, as pathways are co-developed, to ensure practical context-specific solutions are implemented. Focusing on equitable access to diagnostic services, creation of implementable tools for diagnosis and treatment monitoring, and building capacity in the provision of healthcare and specific expertise in osteoporosis care, should be key goals for healthcare services, policymakers and governments. <br/