Heart disease back as top global killer as study highlights 'toll' of chronic conditions, rising youth deaths

Heather Evans nearly died — twice in the same day.

The Calgary resident had two back-to-back heart attacks in 2004, at the age of just 39. One of her sisters had already suffered a heart attack at only 36. Over the next two decades, a devastating pattern became clear: coronary artery disease ran in Evans’s family, and eventually claimed the lives of five of her seven siblings.

“There are always these empty chairs at the table," Evans told CBC News. "We look at each other and it's just … profound sadness and a profound heartache that just never goes away."

A new report on global deaths, published Sunday in The Lancet medical journal, shows that the top causes of mortality around the world are shifting back to familiar threats like heart disease, dislodging COVID-19 as the No. 1 global killer.

Evans's last remaining sister is now in palliative care, while her last remaining brother is experiencing heart failure. At the age of 61, Evans’s own heart is failing, too. But through exercise, a healthy diet and having quadruple bypass open-heart surgery in 2018, she’s doggedly trying to ward off one of the world’s top causes of death.

“It's going to eventually take us,” Evans said. “But we're not going to let it take our spirit.”

Heart disease, stroke and chronic obstructive pulmonary disease (COPD) took the top spots in the latest 2023 data, with COVID dropping from the leading cause of global death in 2021 to the 20th spot just two years later.

Infectious disease deaths in general — including those linked to measles and tuberculosis — have gone down, while chronic conditions that aren’t contagious, such as diabetes, Alzheimer’s disease and drug use disorders, are on the rise.

Patients and researchers warn these slow-burn health threats don’t always get as much attention as a global crisis, yet their impact on people’s health and well-being remains massive.

“It's not as dramatic as an outbreak,” said Michael Brauer, principal research scientist at the Institute for Health Metrics and Evaluation at the University of Washington and a professor at the University of British Columbia. “But we still, I think, do not appreciate the toll that these chronic diseases take.”

Brauer is among a team of 16,500 researchers who have been analyzing global death data on hundreds of diseases across more than 200 countries and territories since 1990.

In Canada, he said the latest data shows heart disease, lung cancer and Alzheimer’s are the top three causes of deaths. Another concerning trend, he told CBC News, is that while overall global mortality is trending down and life expectancy is going up, there are spikes in death rates among teens and young adults in various parts of the world, this country included.

The team’s data for Canada showed an increase in the rates of deaths in all age groups from 15 to 49, Brauer said. Higher death rates among young adults across North America reflect an ongoing trend of “so-called deaths of despair,” the report notes, referring to deaths mainly due to suicide, drug overdoses and alcoholism.

The research team said that’s a call to action to policymakers, with a need to prioritize improved care that addresses the social determinants of health — factors like housing, education and social supports — for these younger age groups.

Jen Mayor, an Ottawa mother who lost her teenage daughter Charlie to suicide earlier this year, said closing health-care gaps to better support struggling youth needs to be a key focus, given how many Canadian teens are coping with mental health problems and addiction.

“We definitely need to hear from the youth. We need to listen to them. We need to understand the strains that they have in their lives,” she said.

Charlie was a much-loved child who suffered from complex mental health struggles, which eventually escalated to self-harm and multiple suicide attempts, her mother explained.

While her daughter had ongoing support from local health-care teams and her school community, Mayor said more proactive, long-term treatment options could help improve care for vulnerable young patients who may slip through the system's cracks.

“Quite often, we would [sit] in the emergency room for 12 hours before we saw a psychologist,” she added.

James MacKillop, a McMaster University professor and the Peter Boris Chair in Addictions Research at St. Joseph's Healthcare Hamilton, agreed there’s a clear need for youth-specific treatment programs in Canada, along with early intervention efforts involving specialized mental health professionals.

He also noted the causes of higher mortality among younger age groups can be complex, ranging from increased feelings of alienation to a toxic drug supply.

The Canada-wide opioid death rate in 2024 actually decreased by 17 per cent from the year before, according to a recent Public Health Agency of Canada report, though the overall numbers remain high. Meanwhile the Canadian Centre on Substance Use and Addiction pointed to changes in the drug supply — and the reality that many vulnerable users have already died — as reasons for that drop in toxic drug deaths.

Canadian pediatricians are now striving to better understand the impact of substance use on children and teens specifically. The Canadian Paediatric Surveillance Program, a joint project of the Public Health Agency of Canada and the Canadian Paediatric Society (CPS), recently launched the first national surveillance study on life-threatening harms tied to illicit substances.

Toxic drug overdose has already become the leading cause of deaths for adolescents in British Columbia, and is a growing concern in the rest of the country, the society noted in a statement to CBC News, adding its “three-year study will allow clinicians and policy makers to co-develop overdose interventions alongside youth to reduce harms and improve health outcomes.”

The complex, overlapping factors involved in mental health and addiction aren’t always captured by simply ranking causes of death, McMaster’s MacKillop noted.

The good news, he added, is that “a lot of the things that are contributing to global mortality now are modifiable.”

Brauer, one of the researchers behind the Lancet report, agreed. Many of the risk factors for chronic health conditions are well-known, including smoking, alcohol, diet and physical activity level, all of which can be addressed to help prevent early death, he said.

In Calgary, Evans stressed that scientists have made immense strides in treating patients like her, allowing her to live for more than two decades after her two heart attacks. But she says she worries that without societal change and an increased focus on healthy eating, personal fitness and reducing stress, more Canadian families will experience losses like hers.

“Had I had the knowledge, I would have tried my best to eat a little bit better, and I would have exercised a heck of a lot more than I did when I was younger, you know?” she said.

“There are so many components to what we can do that can absolutely give us the best chance in life not to get this disease.”