Epidemiology of Cardiovascular Disease¶
Chapter 245 | Part 6: Disorders of the Cardiovascular System
KEY CLINICAL POINTS¶
- Cardiovascular disease (CVD) is the leading cause of death globally, accounting for 19 million deaths in 2022 (33% of global mortality).
- The epidemiologic transition describes a shift in causes of death from infectious diseases to noncommunicable diseases (NCDs), including CVD.
- Global CVD mortality rates have declined in high-income countries (HICs) but increased in low- and middle-income countries (LMICs).
- Key risk factors include tobacco use, poor diet, physical inactivity, hypertension, obesity, diabetes, and genetic predisposition.
- Regional disparities persist, with LMICs experiencing rising CVD rates due to urbanization, lifestyle changes, and limited healthcare access.
1. DEFINITION & OVERVIEW¶
Cardiovascular disease (CVD) is the leading cause of death worldwide, surpassing infectious diseases and malnutrition. It encompasses conditions such as coronary artery disease, stroke, heart failure, and hypertension. CVD accounts for 32% of global deaths, with 16.2% of all deaths attributed to ischemic heart disease (IHD) and 11.6% to stroke in 2019.
Table 245-1 Five Stages of the Epidemiologic Transition¶
| STAGE | DESCRIPTION | DEATHS RELATED TO CVD, % | PREDOMINANT CVD TYPE |
|---|---|---|---|
| Pestilence and famine | Predominance of malnutrition and infectious diseases as causes of death; high rates of infant and child mortality; low mean life expectancy | <10 | Rheumatic heart disease, cardiomyopathies caused by infection and malnutrition |
| Receding pandemics | Improvements in nutrition and public health lead to decrease in deaths related to malnutrition and infection; precipitous decline in infant and child mortality rates | 10–35 | Rheumatic valvular disease, hypertension, CHD, and stroke (predominantly hemorrhagic) |
| STAGE | DESCRIPTION | DEATHS RELATED TO CVD, % | PREDOMINANT CVD TYPE |
|---|---|---|---|
| Degenerative and man-made diseases | Increased fat and caloric intake and decrease in physical activity lead to emergence of hypertension and atherosclerosis; mortality from chronic, noncommunicable diseases exceeds mortality from malnutrition and infectious disease | 35–65 | CHD and stroke (ischemic and hemorrhagic) |
| Delayed degenerative diseases | CVD and cancer are the major causes of morbidity and mortality; age-adjusted CVD mortality declines | 40–50 | CHD, stroke, and congestive heart failure |
| Inactivity and obesity | Overweight and obesity increase at alarming rate; diabetes and hypertension increase; decline in smoking rates levels off | <40 | CHD, stroke, and congestive heart failure, peripheral vascular disease |
1.1 Global Burden¶
CVD is responsible for over 19 million deaths annually (33% of global mortality). In 2022, it accounted for 16.2% of all deaths globally, with ischemic heart disease (IHD) and stroke being the primary contributors. LMICs bear 85% of the global population and are driving the rise in CVD rates.
1.2 Epidemiologic Transition¶
The epidemiologic transition describes a shift in mortality patterns from infectious diseases to noncommunicable diseases (NCDs). This transition is divided into five stages: pestilence and famine, receding pandemics, degenerative and man-made diseases, delayed degenerative diseases, and inactivity and obesity.
2. EPIDEMIOLOGY¶
The global rise in CVD is driven by industrialization, urbanization, and lifestyle changes. CVD mortality rates have declined in HICs but increased in LMICs. In 2019, 15 million CVD deaths occurred in LMICs compared to 3.5 million in HICs. Age-standardized CVD death rates have declined globally by 32.4% since 1990, but population aging and growth in LMICs have offset these reductions.
2.1 Global Trends¶
CVD mortality rates have declined in HICs (e.g., 50–60% reduction over 60 years) but increased in LMICs (15% rise in 20 years). The United States is entering a fifth phase of the epidemiologic transition, with CVD mortality rates increasing since 2020. LMICs account for 85% of the global population and are driving the rise in CVD rates.
2.2 Regional Variations¶
CVD mortality rates vary by region: Eastern Europe and Central Asia have the highest rates (~55% of global CVD deaths), while South Asia and sub-Saharan Africa are experiencing rapid increases. LMICs in South Asia, Latin America, and the Middle East and North Africa are transitioning to higher CVD burdens due to urbanization and lifestyle changes.
3. RISK FACTORS¶
Global CVD rates are influenced by modifiable and non-modifiable risk factors. Key risk factors include tobacco use, poor diet, physical inactivity, hypertension, obesity, diabetes, and genetic predisposition. Smoking causes 8.7 million deaths annually, with higher prevalence in HICs (21.6%) compared to LMICs (11.2%).
3.1 Behavioral Risk Factors¶
Tobacco use: 1.3 billion people use tobacco globally, contributing to 15.4% of all deaths. Physical inactivity: 1.3 million deaths annually. Poor diet: increased saturated fats, trans fats, and simple carbohydrates; decreased plant-based foods.
3.2 Metabolic Risk Factors¶
Hypertension: 1.28 billion adults have hypertension (SBP ≥ 140 mmHg or DBP ≥ 90 mmHg). Diabetes: 476 million people globally, with 80% in LMICs. Obesity: 892 million adults projected to be obese by 2025.
3.3 Genetic Risk Factors¶
Genetic variants contribute to CVD risk, with hundreds of variants associated with lipid levels, hypertension, and diabetes. Clonal hematopoiesis of indeterminate potential (CHIP) is linked to increased CHD risk (up to twofold).
4. SPECIAL CONSIDERATIONS¶
CVD disproportionately affects LMICs due to limited healthcare access, poor disease management, and socioeconomic disparities. In LMICs, 80% of people with diabetes live in these regions, and 50% of CVD deaths occur in individuals <70 years old. The burden of stroke is three times higher in LMICs than in HICs.
4.1 LMICs¶
LMICs account for 85% of the global population and are experiencing rapid CVD growth due to urbanization, lifestyle changes, and limited healthcare access. CVD mortality rates in LMICs have increased by 54% since 1990, with age-adjusted rates rising due to population aging.
4.2 HICs¶
HICs have seen declines in CVD mortality (32.4% reduction since 1990) but face challenges with aging populations and rising obesity rates. CVD remains the leading cause of death in HICs, with CHD accounting for 25% of all deaths.
10. KEY POINTS & CLINICAL PEARLS¶
CVD is the leading cause of death globally, with LMICs experiencing the fastest growth in rates. The epidemiologic transition highlights the shift from infectious to noncommunicable diseases. Key risk factors include tobacco, poor diet, physical inactivity, hypertension, obesity, and diabetes. Global efforts to reduce CVD require population-wide interventions targeting modifiable risk factors and improving healthcare access in LMICs.