Scotland could experience a 16% increase in the annual burden of disease by 2040, even as its population begins to decline, according to new research published by Public Health Scotland on 20 October 2026.
The findings expose a fundamental problem for future healthcare planning: a falling population does not necessarily mean fewer people requiring substantial medical treatment, rehabilitation or social care.
Seven of Scotland’s 14 territorial NHS boards are projected to lose residents between 2025 and 2040. Yet every board is expected to experience an increase in the combined effects of illness, disability and premature death under the study’s demographic scenario.
The principal reason is population ageing. As more people survive into their seventies, eighties and nineties, the number living with conditions that become more common in later life is expected to increase.
The researchers identify cardiovascular disease, cancer and neurological disorders as the largest contributors to the projected increase. Common infections, diabetes, kidney disease and accidental injuries are among the conditions showing particularly substantial relative growth.
Scotland is entering a period in which demographic projections point towards a shrinking population, a smaller proportion of working-age residents and a substantially larger older population.
They also challenge a straightforward approach to healthcare funding based on population numbers alone. An area losing residents may simultaneously require more complex medical care, additional community support and greater investment in services for older people.
What the New Research Actually Measures
The Scottish Burden of Disease study, published on 20 October, examines how changing population size and age distribution could affect health loss between 2025 and 2040.
It uses a measure called disability-adjusted life years, or DALYs.
One DALY represents one year of healthy life lost. The measure combines years lost through premature death with years lived in poor health or disability.
This allows researchers to compare the effects of conditions that kill prematurely with those that cause people to live for prolonged periods with illness or disability.
A cancer causing premature death, for example, may generate substantial years of life lost. A neurological or musculoskeletal condition may cause a person to survive for many years while experiencing significant health limitations.
Both contribute to the total burden of disease, although in different ways.
The new research applies age- and sex-specific disease-burden rates from 2019 to projected populations in 2025 and 2040.
In other words, it asks what could happen if the likelihood and severity of disease within particular age and sex groups remained at their 2019 levels while the number of people in those groups changed.
It is not a prediction that medical treatments will fail to improve or that disease rates must inevitably increase. It deliberately holds existing rates constant to isolate the effects of demographic change.
Nor does a 16% increase in disability-adjusted life years mean that hospital admissions, NHS spending or the number of patients will necessarily rise by exactly 16%.
Those are related but separate measures, influenced by treatment effectiveness, workforce availability, service design and the cost of care.
The research instead provides an indication of the additional health burden Scotland could face if demographic change is not accompanied by improvements in prevention, treatment and population health.
Every Scottish NHS Board Faces a Rising Burden
The study estimates that Scotland’s annual disease burden could rise by 16% nationally over the 15-year period.
The projected increase is 14% in the western NHS planning area and 18% in the eastern planning area.
Within Scotland West, the estimated increase varies between approximately 10% and 17% across individual territorial health boards.
In Scotland East, the corresponding range is approximately 15% to 22%.
These are changes relative to each area’s existing disease burden. They do not establish that the eastern region will have a greater overall burden, more illness per resident or greater deprivation than the western region.
The study makes a particularly important finding about areas expected to lose population.
Four territorial boards in Scotland West and three in Scotland East are projected to experience population decline. Despite this, their estimated disease burden still rises.
The explanation lies in the changing composition of their populations. A community may have fewer residents overall but more people in older age groups with greater average healthcare needs.
The public-health consequence is significant for service planning. Reducing healthcare provision simply because an area’s population has declined could fail to account for the increasing complexity and intensity of care required by those who remain.
Scotland’s Population Is Already Approaching a Turning Point
The disease projections are consistent with a separate demographic warning issued by National Records of Scotland on 28 April 2026.
Its latest national population projections indicate that Scotland’s population will increase only modestly until 2033 before beginning to decline from 2034.
The population is projected to reach approximately 5.56 million in 2033, then fall below its 2024 level of approximately 5.55 million by 2040.
By 2049, the projected total is approximately 5.47 million, representing a decline of 1.3% compared with 2024.
However, those relatively small changes in the overall population conceal substantial changes in its age structure.
The number of people aged 75 and over is projected to increase by approximately 300,700 between 2024 and 2049.
At the same time, the number of children aged 15 and under is expected to fall by approximately 165,900, while the population aged 16 to 29 is projected to fall by approximately 157,500.
The proportion of residents of pensionable age is projected to increase from 19.2% in 2024 to 22.5% in 2049, taking account of scheduled changes to the State Pension age.
These are 25-year population projections, not estimates of the change in disease burden by 2040. They provide broader demographic context for the shorter-term health study.
Scotland is also projected to experience more deaths than births, with positive migration no longer sufficient to offset that natural decline from the middle of the 2030s.
The combination of population ageing and declining numbers of younger residents has implications beyond hospitals. Health and social care services will have to operate within a society where the proportion of potential workers is under increasing demographic pressure.
The Diseases Expected to Create the Greatest Pressure
Public Health Scotland identifies three broad groups of disease that are expected to remain the largest contributors to health loss across every territorial board by 2040: cancers, cardiovascular diseases and neurological disorders.
Cardiovascular disease includes conditions affecting the heart and blood vessels, such as coronary heart disease and stroke.
Neurological disorders cover a range of conditions affecting the nervous system, including diseases associated with later life and substantial long-term disability.
Cancer remains a major contributor both because of premature mortality and because treatment and its consequences can affect health over extended periods.
These three disease groups are also expected to account for the largest absolute increases in health loss nationally.
However, the study identifies other conditions with particularly rapid relative growth. Common infections, unintentional injuries, diabetes and kidney diseases are among the groups showing substantial increases under the demographic scenario.
A relatively uncommon condition can show a large percentage increase without becoming one of the largest causes of illness overall. Conversely, a condition already responsible for considerable health loss can create a much larger absolute increase even if its percentage growth is slower.
For healthcare planning, both measures are relevant. Large absolute burdens help determine where substantial capacity may be needed, while rapidly growing conditions may require earlier investment in specialist services and prevention.
Musculoskeletal disorders and mental health conditions also remain important contributors across Scotland. Substance-use disorders feature among the leading causes in Scotland West.
The findings point towards a healthcare system that will increasingly need to manage multiple long-term conditions simultaneously, rather than treating every illness as a separate, isolated episode.
The Most Troubling Finding Concerns Deprivation
One of the study’s more easily misunderstood findings is that some of the largest projected percentage increases in disease burden occur in health boards serving comparatively less deprived populations.
At first glance, this could be interpreted as indicating that more affluent communities will face greater health needs than poorer ones.
Public Health Scotland explicitly warns against that interpretation.
The explanation is linked to existing inequalities in how long people live.
Residents of more deprived communities are more likely to experience serious illness at younger ages and to die prematurely. Consequently, fewer survive into the oldest age groups, where the projected increase in age-related disease burden is steepest.
A smaller projected percentage increase can therefore coexist with a much worse current burden of illness, earlier deaths and fewer years of healthy life.
The scale of Scotland’s existing inequality is substantial.
Public Health Scotland’s March 2026 health inequalities report recorded an 11.1-year difference in male life expectancy between the most and least deprived fifths of Scottish areas. The corresponding difference for females was 8.7 years.
The differences in healthy life expectancy were considerably larger: 20.8 years for males and 23.4 years for females.
These figures refer to the periods used in those published statistics and are not projections to 2040.
They illustrate why allocating future healthcare resources only according to population growth or projected percentage increases could produce misleading results.
Areas with greater deprivation may require sustained additional resources even where their population is ageing less rapidly or their relative increase in disease burden appears smaller.
The Consequences for Rural and Island Communities
The study also raises questions about access to treatment in rural Scotland and the islands.
In geographically dispersed communities, population decline does not necessarily reduce the fixed costs of delivering healthcare.
Hospitals, ambulance services, community nursing, specialist clinics and emergency transport may still be required across large areas, even when the number of residents falls.
As the population ages, the services required may also become more complex.
Older patients are more likely to require treatment for several conditions, repeated monitoring, rehabilitation and coordinated health and social care.
Travel presents an additional consideration for patients requiring frequent appointments, particularly where specialist services are concentrated in larger towns or cities.
The Scottish Burden of Disease report does not calculate travel times, transport costs or the future location of hospital services. Its findings cannot therefore be used to demonstrate that a particular hospital should expand, close or transfer services elsewhere.
But it provides an important warning against assuming that demand falls automatically when the population declines.
Any decision to reorganise services would need to consider age-related disease burden, existing inequalities, geographical accessibility and the practical capacity of community services to support patients closer to home.
What the Figures Mean for NHS Planning
The publication arrives as Scotland examines changes to its health and social care system, including the proposed consolidation of territorial NHS boards into larger regional structures.
There is an important distinction between the study’s two NHS planning areas and the government’s proposals for future administrative organisations.
Public Health Scotland states that east and west regional planning areas began operating in November 2025 alongside existing NHS board planning.
Its projections use those planning areas for statistical analysis. They do not assume that the government’s later proposals to replace territorial boards have been approved or implemented.
The research therefore provides evidence about future disease burden, not an endorsement of any particular administrative restructuring.
Indeed, the findings suggest that planning at regional level must retain detailed knowledge of the different needs within individual communities.
A single region may contain growing urban populations, ageing rural areas, communities with severe deprivation and places where relatively few residents live far from specialist services.
Measures based solely on total regional population could obscure those differences.
For future investment, the relevant questions concern the number of healthy years lost, when illness occurs, which conditions cause the greatest burden and how much need could be prevented or reduced through intervention.
Can the Projected Increase Be Prevented?
The 16% figure is not inevitable.
The study assumes that disease-burden rates within individual age and sex groups remain at their 2019 levels. It does not forecast the effects of new medicines, improved diagnosis, changes in smoking or alcohol consumption, better cardiovascular prevention or improved living conditions.
Nor does it model the possibility that public health could deteriorate, leaving more people ill at younger ages.
Public Health Scotland’s researchers emphasise that prevention, early diagnosis and improvements in the wider determinants of health could materially change the outcome.
These factors include housing, income, employment, education, environmental conditions and access to timely healthcare.
The potential advantage of prevention is not confined to avoiding premature deaths. Effective intervention can reduce the years people spend living with serious illness or disability.
That is particularly relevant for chronic conditions where earlier detection, treatment and support may delay complications or preserve independence.
The research therefore offers a measurable warning about what demographic change could produce if underlying patterns of illness remain unchanged.
The central finding is that Scotland may need to provide care for fewer people overall while dealing with a substantially greater burden of illness.
How the country prepares for that possibility will depend on decisions taken well before 2040, including investment in prevention, the organisation of community care and the ability of health services to respond to the changing needs of an ageing population.
Sources
Scottish Burden of Disease Study: Exploring the Future Burden of Disease Across Scotland’s NHS Sub-National Planning Areas — The Impact of Demographic Change, 2025 to 2040. Public Health Scotland, 20 October 2026.
Read the research
Scotland’s Health — Latest Report Projects Burden of Disease, but the Future Is Not Fixed. Dr Fatim Lakha and Grant Wyper, Public Health Scotland, 20 October 2026.
Read the researchers’ explanation
Projected Population of Scotland: 2024-Based. National Records of Scotland, 28 April 2026.
Read the population projections
Long-Term Monitoring of Health Inequalities in Scotland by Area Deprivation. Public Health Scotland, 24 March 2026.
Read the health inequalities report
What the Latest Healthy Life Expectancy Estimates Tell Us. Public Health Scotland, 19 February 2026.
Read the public health analysis
