Research indicates that Alzheimer's could be preceded by 10 health conditions years before diagnosis. Major depressive disorder was pinpointed as the earliest associated condition, surfacing nine years prior to an Alzheimer's diagnosis.

Other connected conditions include anxiety, constipation and weight loss. However, it remains uncertain whether these linked conditions are symptoms, risk factors, causes or warning signs of Alzheimer's. Alzheimer's disease, a brain disorder resulting in memory loss and declining cognitive abilities over time, is thought to account for up to 70% of dementia cases.

The researchers behind the study have labelled Alzheimer's as one of the 'principal health challenges of the 21st century'. Despite the cause of Alzheimer's being unknown and no cure available, the NHS has identified several factors believed to increase your risk of developing the condition.

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These are getting older, age, family history, untreated depression, and lifestyle factors and conditions associated with heart disease. Published in The Lancet Digital Health, the Paris Brain Institute aimed to confirm well-known dementia risk factors and uncover others. This research could lay the groundwork for early or new interventions into this devastating condition.

The team looked at data from 20,214 UK patients over a 24-year span and 19,458 individuals in France over 21 years. This study is the first to identify constipation as a potential risk factor that emerges seven years before an Alzheimer's diagnosis.

• Major depression


• Anxiety


• Constipation


• Abnormal weight loss


• Reaction to severe stress


• Sleep disorders


• Hearing loss


• Type of arthritis known as cervical spondylosis


• Falls


• Fatigue

Thomas Nedelec, a researcher from the Aramis team, commented to say: "The connections made allowed us to confirm known associations, such as hearing problems or depression, and other less known factors or early symptoms, such as cervical spondylosis or constipation."

He further noted: "However, we are only reporting statistical associations. These will have to be the subject of further studies to understand the underlying mechanisms. The question remains as to whether the health problems encountered are risk factors, symptoms, or warning signs of the disease."