Australian scientists have discovered that two distinctive signs of dementia unrelated to memory can appear 11 years before typical symptoms. According to a study conducted at Monash University in Melbourne, rapid weight loss and high levels of “good” cholesterol are among the early warning signs of dementia. The research team examined heart and metabolism health data of 1,078 dementia patients and 4,312 individuals without the disease. The results showed that those diagnosed with dementia experienced a significant decrease in body mass index (BMI) and waist circumference up to 11 years before diagnosis. Additionally, about five years before diagnosis, levels of high-density lipoprotein (HDL) cholesterol, known as “good” cholesterol, were observed to be higher in individuals with dementia compared to those without the disease. HDL cholesterol is known to have a protective effect against heart and vascular diseases.

The researchers state that these findings provide important information about the changes the body undergoes before dementia and emphasize that individuals at higher risk of developing the disease can be diagnosed and treated early. In a study published in the JAMA journal, scientists highlighted that dementia has a long clinical pre-dementia phase, suggesting that symptoms of the disease can begin years before diagnosis. While it is estimated that about one million people in the UK have dementia, this number is expected to reach 1.4 million by 2040. The participants in the study were regularly measured for nine cardiometabolic factors over a span of 11 years. These factors included waist circumference, body weight, height, blood pressure, HDL and LDL cholesterol levels, as well as triglyceride values. The results revealed significant changes in body shapes and lipid levels in dementia patients up to 10 years before the onset of symptoms.

The researchers suggest that cognitive decline could lead to reduced appetite and worsening cooking skills, causing weight loss. It is stated that individuals diagnosed with dementia are often more likely to live alone, which can negatively impact their eating habits. Furthermore, scientists argue that dementia can affect body composition by influencing brain structure. Smaller studies also support this hypothesis. The authors of the study note that the findings contribute significantly to dementia research. They stated, “Our results indicate that weight loss before dementia occurs much earlier than previously reported.” It is believed that neuropathological changes such as amyloid accumulation could begin 15 to 24 years before diagnosis. Experts emphasize that changes in the body start before symptoms appear and early detection can alter the course of the disease.