and treatment modalities

Leading Causes of Death

The trends impacting changes in the leading causes of death, and how they relate to newer diagnostic and treatment modalities.

By Jim Poggi

Despite the fact that new diagnostic testing and treatment modalities have continued to ad-

vance in recent years, the ranking of the 10 leading causes of death in the United States has remained pretty consistent. However, their trends have not due to changes in health habits and treatment improvements addressing specific conditions. The top 10 in order remain: heart disease, cancer, unintentional injuries, chronic lower respiratory diseases (COPD, emphysema), stroke, Alzheimer disease, diabetes, influenza and pneumonia, kidney disease and suicide. In this column, I will discuss the trends impacting changes in the leading causes of death, how they relate to newer diagnostic and treatment modalities, and speculate a bit on how I see the future.

What changed the outlook for morbidity and mortality? From a big picture perspective, what has changed since 1980 to influence the decline in death rates for many of the leading causes of death? Diagnostic imaging, including MRI and CT scans, have made a big difference for heart disease (diagnosis of ischemia and arterial blockage in particular). Newer scanning techniques have also impacted cancer, with low dose CT scans available for Medicare beneficiaries annually who have a history of smoking. Commercial health insurance coverage is also available. Colonoscopies have also had a dramatic effect on the diagnosis of colorectal cancer, with earlier diagnosis leading to far better outcomes. As a result, lung cancer deaths have seen a steady decline in recent years.

On the lab side of things, changes have been fundamental. For heart disease, acute cardiac injury is rapidly and accurately diagnosed with Troponin I, and high sensitivity Troponin I promises better outcomes still for acute injury and, more recently, for identification of obstructive coronary artery disease and confirmation of congestive heart failure. On the chronic heart disease front, BNP and lipid testing in combination with evaluation of other risk factors including prediabetes using hemoglobin A1c provide earlier alerts of the need to make lifestyle changes, including a reduction in weight, improved diet and increase in exercise to reduce risk factors for heart attack and also stroke.

Where are the wins?

The results for heart disease and cancer especially have been impressive, and continue to get better, with even newer technologies on the horizon. Since 1980, overall death rates have declined by 50%, which is a clear tribute to advances in medical care. Heart disease has shown the most dramatic decline in death rates over time, with a reduction of over 53%. From a treatment perspective, management of ischemic heart disease has benefited from better blood

pressure medications as well as stent and coronary artery bypass graft availability. A level of cardiac functionality can now be restored following an initial heart attack, based on rapid diagnosis and intervention. The statistics show we are clearly winning here.

Cancer diagnosis and treatment has also undergone revolutionary changes, from imaging (low dose CT and colonoscopy) to improved diagnostic tests, including novel molecular assays which can predict risk levels and even provide guidance for therapy. Multianalyte assays with algorithms have grown in number and acceptance and are influencing treatment decisions for breast, colorectal, prostate and other cancers daily. There are even predisposition assays intended to predict whether a patient’s genotype could lead to development of cancer later in life. Big changes in diagnosis are upon us.

On the treatment side of things, so much has changed! Novel immunotherapy agents are showing promise. We are gaining a clearer understanding of the metabolic changes that take place as cells become cancerous and we are learning how some cancer cells can evade detection by the immune system. As a result, we are developing a cascade of treatment options for recurring cancer to facilitate better outcomes. CAR-T technologies are being employed to create a stronger immune response and help the body heal itself naturally.

Stroke death rates have also dropped noticeably in the recent past. Recent studies show a reduction in stroke incidence of 11.3% from 1990 to 2017. Perhaps more importantly there has been a 34% reduction in stroke mortality considered to be largely attributable to better management of risk factors by patients and better interventional and treatment techniques. As the U.S. population continues to age, while the incidence of stroke and reductions in mortality are seen, the total number of patients experiencing a stroke is increasing. This is largely a factor of changing demographics.

found by following this link: Health, United States 2019 (cdc.gov).

What’s on the horizon?

Newer continuous glucose monitoring solutions are leading to better control of diabetes, increased patient convenience and better dietary compliance. At the same time, wearable

technology couples the results for these glucose values and so much more data. Several companies are working to create solutions that combine vital signs data (pulse rate, respiration, etc.) with sensor data (glucose, ketones, respiratory measurements, etc.) and evaluating data from the individual patient to predict weight loss and monitor progress with dietary or other patient treatment programs. At a very high level, they also use population data to predict outcomes and recommend “best practices” for weight control and other behavioral changes.

I see a continuing expansion of applications in behavioral health as a key future trend to reduce morbidity and mortality. Harnessed properly, they should be able to impact diabetes death rates that have remained stubbornly resistant to better lab tests and a general increase in our understanding of the metabolic patterns related to the development of diabetes. Exciting times are ahead.

The results for heart disease and cancer especially have been impressive, and continue to get better, with even newer technologies on the horizon. Since 1980, overall death rates have declined by 50%, which is a clear tribute to advances in medical care.

Where is further progress needed?

With all this progress, there are several of the leading causes of death that have not seen notable reductions in incidence. Diabetes and kidney disease death rates are relatively unchanged. Diabetes death rates are largely the same from 1950 forward, and kidney disease death rates have actually increased since 1980 when mortality rates were first reported. Alzheimer disease rates have risen by more than 60% since 2000. Similarly, both suicide and homicide death rates have increased slightly over the reporting period, perhaps suggesting that behavioral health advancements are still on the horizon. Unintentional injuries have shown the largest amount of variation over the years, but remain the third leading cause of death, primarily attributed to males between mid teen years and mid 20s. The full data set showing the changes in morbidity and mortality is provided by the CDC and can be