Cholesterol is transported around the body in the bloodstream on proteins called lipoproteins. There are two types of lipoprotein: low-density lipoprotein (LDL), which is sometimes called “bad” cholesterol and high-density lipoprotein (HDL), also referred to as “good cholesterol.”
A high LDL level is associated with an increased risk for heart disease and stroke. LDL transports cholesterol to the arteries, and when the LDL level is elevated, this cholesterol can accumulate in the blood vessel walls and contribute to the formation of a plaque.
This plaque formation, or atherosclerosis, can eventually cause the vessel to narrow and decrease blood flow to the heart (coronary artery disease). If the vessel becomes blocked so that blood no longer reaches the heart or brain, this can result in chest pain (angina), heart attack, or stroke.
Atherosclerosis 3d illustration. Credit: Sciencepics / Shutterstock
HDL carries cholesterol to the liver, where it is removed from circulation and eliminated from the body. In this way, HDL can prevent plaque formation, protect the arteries, and reduce the risk for cardiovascular disease. It is generally considered that the higher the level of this good cholesterol, the lower the risk is for heart disease, vascular disease, and stroke.
Structure of lipoprotein, the low-density lipoprotein (LDL). Image Credit: Ellepigrafica / Shutterstock
One-third of the US population has elevated LDL
More than one-third of the US population has an elevated LDL level. People with high LDL are advised to make lifestyle changes and to use cholesterol-lowering medications if lifestyle changes alone are insufficient. Lower LDL levels are better, to a point, but a recommended goal is a blood level of less than 130 mg/dL among people who do not have atherosclerosis or diabetes. For those conditions, the recommended target may be lower.
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The main approaches to lowering LDL cholesterol are dietary and lifestyle changes. Initial steps may include following a low-fat diet, engaging in aerobic activity, losing weight, and reducing waist circumference. In cases where these changes are not enough to lower LDL, a cholesterol-lowering medication such as a statin may be prescribed.
Hypercholesterolemia
In rare cases, people have a very high LDL level as the result of an inheritable genetic disease called hypercholesterolemia that reduces the liver’s ability to clear excess cholesterol. The very high LDL level can lead to heart attack and stroke among younger individuals, meaning medication may be required to prevent or treat atherosclerotic heart disease at an earlier age.
One group of researchers tried to dispute the link between elevated LDL and heart disease
Recently, one group of researchers has challenged the connection between raised LDL and heart disease.
A 2018 article published in the journal Expert Review of Clinical Pharmacologychallenged the long-held belief that “bad” LDL cholesterol causes heart disease.
Lead author Uffe Ravnskov and colleagues claimed that the cholesterol hypothesis is based on “misleading statistics, exclusion of unsuccessful trials, and by ignoring numerous contradictory observations.”
The authors also stated that statin treatment, particularly when used as primary prevention, is of doubtful benefit.
Another study by the same group published in BMJ Open in 2016 reviewed previous research studies covering almost 70,000 people and reported no association between elevated LDL and premature death from cardiovascular disease among people older than 60. In fact, study author Malcolm Kendrick reported that 92% of the individuals who had high cholesterol lived longer and had less heart disease.
“Since elderly people with high LDL-C live as long or longer than those with low LDL-C, our analysis provides reason to question the validity of the cholesterol hypothesis,” wrote Ravnskov, a former associate professor of renal medicine at Lund University in Sweden.
The authors also believed that their study called for a re-evaluation of the guidelines for cardiovascular prevention, “in particular because the benefits from statin treatment have been exaggerated.”
Co-author Sherif Sultan from the University of Ireland described cholesterol as one of the “most vital” molecules in the body and said it prevents infection, cancer, muscle pain, and other conditions among the elderly:
“Lowering cholesterol with medications for primary cardiovascular prevention in those aged over 60 is a total waste of time and resources, whereas altering your lifestyle is the single most important way to achieve a good quality of life.”
Ravnskov also said there was “no reason” to lower elevated LDL.
Research slammed by critics
However, epidemiologist Colin Baigent from Oxford University said the analysis had “serious weaknesses and, as a consequence, has reached completely the wrong conclusion.”
Consultant cardiologist Tim Chico from the University of Sheffield, was also skeptical, saying that a randomized study where some patients received a cholesterol-lowering drug while others received a placebo would be more convincing. He said such studies have been conducted before and have shown that lowering cholesterol with medication does reduce the risk of heart disease in the elderly: “I find this more compelling than the data in the current study.”
The British Heart Foundation (BHF) also questioned the research and stressed that the link between high LDL and death among the elderly is more challenging to detect because, as people age, more factors influence overall health.
A BHF spokesperson concluded: “There is nothing in the current paper to support the authors’ suggestions that the studies they reviewed cast doubt on the idea that LDL cholesterol is a major cause of heart disease or that guidelines on LDL reduction in the elderly need re-evaluating.”
The Canadian government says it will donate up to 200,000 vaccine doses to fight the mpox outbreak in Congo and other African countries.
It says the donated doses of Imvamune will come from Canada’s existing supply and will not affect the country’s preparedness for mpox cases in this country.
Minister of Health Mark Holland says the donation “will help to protect those in the most affected regions of Africa and will help prevent further spread of the virus.”
Dr. Madhukar Pai, Canada research chair in epidemiology and global health, says although the donation is welcome, it is a very small portion of the estimated 10 million vaccine doses needed to control the outbreak.
Vaccine donations from wealthier countries have only recently started arriving in Africa, almost a month after the World Health Organization declared the mpox outbreak a public health emergency of international concern.
A few days after the declaration in August, Global Affairs Canada announced a contribution of $1 million for mpox surveillance, diagnostic tools, research and community awareness in Africa.
On Thursday, the Africa Centres for Disease Control and Prevention said mpox is still on the rise and that testing rates are “insufficient” across the continent.
Jason Kindrachuk, Canada research chair in emerging viruses at the University of Manitoba, said donating vaccines, in addition to supporting surveillance and diagnostic tests, is “massively important.”
But Kindrachuk, who has worked on the ground in Congo during the epidemic, also said that the international response to the mpox outbreak is “better late than never (but) better never late.”
“It would have been fantastic for us globally to not be in this position by having provided doses a much, much longer time prior than when we are,” he said, noting that the outbreak of clade I mpox in Congo started in early 2023.
Clade II mpox, endemic in regions of West Africa, came to the world’s attention even earlier — in 2022 — as that strain of virus spread to other countries, including Canada.
Two doses are recommended for mpox vaccination, so the donation may only benefit 100,000 people, Pai said.
Pai questioned whether Canada is contributing enough, as the federal government hasn’t said what percentage of its mpox vaccine stockpile it is donating.
“Small donations are simply not going to help end this crisis. We need to show greater solidarity and support,” he said in an email.
“That is the biggest lesson from the COVID-19 pandemic — our collective safety is tied with that of other nations.”
This report by The Canadian Press was first published Sept. 13, 2024.
Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.
HALIFAX – The Nova Scotia government says it could be months before it reveals how many people are on the wait-list for a family doctor.
The head of the province’s health authority told reporters Wednesday that the government won’t release updated data until the 160,000 people who were on the wait-list in June are contacted to verify whether they still need primary care.
Karen Oldfield said Nova Scotia Health is working on validating the primary care wait-list data before posting new numbers, and that work may take a matter of months. The most recent public wait-list figures are from June 1, when 160,234 people, or about 16 per cent of the population, were on it.
“It’s going to take time to make 160,000 calls,” Oldfield said. “We are not talking weeks, we are talking months.”
The interim CEO and president of Nova Scotia Health said people on the list are being asked where they live, whether they still need a family doctor, and to give an update on their health.
A spokesperson with the province’s Health Department says the government and its health authority are “working hard” to turn the wait-list registry into a useful tool, adding that the data will be shared once it is validated.
Nova Scotia’s NDP are calling on Premier Tim Houston to immediately release statistics on how many people are looking for a family doctor. On Tuesday, the NDP introduced a bill that would require the health minister to make the number public every month.
“It is unacceptable for the list to be more than three months out of date,” NDP Leader Claudia Chender said Tuesday.
Chender said releasing this data regularly is vital so Nova Scotians can track the government’s progress on its main 2021 campaign promise: fixing health care.
The number of people in need of a family doctor has more than doubled between the 2021 summer election campaign and June 2024. Since September 2021 about 300 doctors have been added to the provincial health system, the Health Department said.
“We’ll know if Tim Houston is keeping his 2021 election promise to fix health care when Nova Scotians are attached to primary care,” Chender said.
This report by The Canadian Press was first published Sept. 11, 2024.
ST. JOHN’S, N.L. – Newfoundland and Labrador‘s chief medical officer is monitoring the rise of whooping cough infections across the province as cases of the highly contagious disease continue to grow across Canada.
Dr. Janice Fitzgerald says that so far this year, the province has recorded 230 confirmed cases of the vaccine-preventable respiratory tract infection, also known as pertussis.
Late last month, Quebec reported more than 11,000 cases during the same time period, while Ontario counted 470 cases, well above the five-year average of 98. In Quebec, the majority of patients are between the ages of 10 and 14.
Meanwhile, New Brunswick has declared a whooping cough outbreak across the province. A total of 141 cases were reported by last month, exceeding the five-year average of 34.
The disease can lead to severe complications among vulnerable populations including infants, who are at the highest risk of suffering from complications like pneumonia and seizures. Symptoms may start with a runny nose, mild fever and cough, then progress to severe coughing accompanied by a distinctive “whooping” sound during inhalation.
“The public, especially pregnant people and those in close contact with infants, are encouraged to be aware of symptoms related to pertussis and to ensure vaccinations are up to date,” Newfoundland and Labrador’s Health Department said in a statement.
Whooping cough can be treated with antibiotics, but vaccination is the most effective way to control the spread of the disease. As a result, the province has expanded immunization efforts this school year. While booster doses are already offered in Grade 9, the vaccine is now being offered to Grade 8 students as well.
Public health officials say whooping cough is a cyclical disease that increases every two to five or six years.
Meanwhile, New Brunswick’s acting chief medical officer of health expects the current case count to get worse before tapering off.
A rise in whooping cough cases has also been reported in the United States and elsewhere. The Pan American Health Organization issued an alert in July encouraging countries to ramp up their surveillance and vaccination coverage.
This report by The Canadian Press was first published Sept. 10, 2024.
