Protecting the gains: What changes are needed to prevent a reversal of the downward cardiovascular disease mortality trend?

Abstract

Aims: Cardiovascular disease (CVD) mortality has decreased over 60% over the past 50 years in the United States; however, emerging data indicate CVD incidence may be rising because of shifting demographics, increasing risk factor prevalence, and competing needs for limited resources. We projected CVD mortality from 2015 to 2040 given varying informed assumptions regarding changes in risk factor prevalence, uptake of current therapeutic options, and future innovations.

Methods: A microsimulation model was used to project US CVD mortality trends. National Health and Nutrition Examination Survey data were used to estimate population-level trends in CVD risk factors. Risk factors were used to generate Framingham Risk Scores for cohorts of 1 000 000 individuals from the general population to determine each individuals' CVD risk. Annual cardiovascular incidence, prevalence, and mortality were projected for scenarios differing by uptake of current therapies, anticipated pharmaceutical innovations with variable efficacy, risk factor prevalence, and changes in health disparities.

Results: When incorporating a demographic shift, continued changes in risk factors, current treatment utilization, and no major innovations, we predicted the CVD mortality rate would increase 41% by 2040. If innovations providing incremental benefits equal to those associated with the introduction of statins are identified and widely utilized, CVD mortality could remain constant through 2040. With more efficacious innovations, CVD mortality could be further reduced.

Conclusions: Given demographic and risk prevalence changes, increasing access and adherence to current preventative therapeutics could slow the expected mortality increase, but new therapies may be needed to maintain the downward trend in CVD deaths.

Keywords: cardiovascular disease; disease burden; microsimulation model; mortality; projections.

Figure 1

Model schematic. CHD, coronary heart disease; CVD, cardiovascular disease

Figure 2

A 2040 mortality rates based on projected changes in risk factors. CVD, cardiovascular disease; HDL‐C, high‐density lipoprotein cholesterol. Solid vertical line reflects projected mortality rate of 355 per 100 000 individuals with current risk factors. Dark bars indicate risk factor changes that will increase mortality compared to no changes in risk factors, light bars indicate those that will decrease mortality. Numbers beside bars show the CVD mortality rate per 100 000, percentages indicate the change compared with mortality rate with current risk factors. For comparison, the model‐projected mortality rate for 2015 is 218 deaths per 100 000 individuals and depicted with the dotted vertical line. Results reflect the following changes in risk factors, as projected from NHANES from 2015 to 2040: smoking prevalence: decrease from 18% to 4%; diabetes prevalence: increase from 14% to 24%; total cholesterol: projected decrease from 191 to 163 mg/dL; hypertension treatment: increase from 27% to 40%; systolic blood pressure: decrease from 122.0 to 115.8 mmHg; HDL‐C: decrease from 52.4 to 49.6 mg/dL

Figure 3

A, Cardiovascular disease mortality projections following innovations reducing total cholesterol. CVD, cardiovascular disease; NHANES, national health and nutrition examination survey. Figure depicts the CVD mortality trends given differing assumptions regarding future total cholesterol levels. The top line reflects changes in cholesterol as projected by NHANES. Each subsequent line reflects a decrease in total cholesterol beyond the change projected by NHANES. B, CVD mortality projections following innovations reducing systolic blood pressure. CVD, cardiovascular disease; NHANES, national health and nutrition examination survey. Figure depicts the CVD mortality trends given differing assumptions regarding future systolic blood pressure levels. The top line reflects changes in systolic blood pressure as projected by NHANES. Each subsequent line reflects a decrease in systolic blood pressure beyond the change projected by NHANES

Figure 4

Mortality projections for three scenarios. CVD, cardiovascular disease; NHANES, national health and nutrition examination survey. Figure depicts the historical rates of CVD mortality, and the projected rates under three scenarios. Historical data based on publication by Ma et al.25 Future increases without innovations driven by a rapidly increasing CVD prevalence rate

Figure A1

Historical and projected risk factor values: total cholesterol. A, The decrease in total cholesterol based on an analysis of NHANES data from 2003 to 2014. B, The decrease in high‐density lipoprotein based on an analysis of NHANES data from 2003 to 2014. C, The decrease in systolic blood pressure based on an analysis of NHANES data from 2003 to 2014. D, The increase in systolic blood pressure treatment based on an analysis of NHANES data from 2003 to 2014. E, the increase in diabetes prevalence based on an analysis of NHANES data from 2003 to 2014. F, The decrease in smoking rates based on an analysis of NHANES data from 2003 to 2014