When people hear the word dementia, they are very likely to immediately think of Alzheimer’s disease. And while Alzheimer’s is the most common form, accounting for 60 to 80 % of cases worldwide, it is far from the only type of dementia. A range of other, lesser-known dementias can be equally devastating, and recognising them early can lead to better care and improved quality of life.
So, what are these lesser-known types of dementia?
Vascular Dementia
Vascular dementia is the second-most common type of dementia, and is estimated to be about 40 % of all dementia cases in India. It is triggered by reduced blood flow to the brain, often after strokes or due to chronic conditions such as hypertension and diabetes. Its sudden onset, rapid decline or step-by-step decline after ‘mini strokes’, and link to future strokes, makes this type very dangerous. However, unlike Alzheimer’s, it’s often preventable. Early diagnosis, blood pressure and sugar control, and a healthy lifestyle can delay its progression.
Frontotemporal Dementia
Sometimes misdiagnosed as a psychiatric illness, frontotemporal dementia (FTD) is an umbrella term for brain disorders that affect the frontal and temporal lobes of the brain. These sites are associated with personality, behaviour and language, and thus some people undergo personality changes or become more impulsive or emotionally indifferent when suffering from this condition.
About 60 % of people diagnosed with FTD fall within the age bracket of 45 to 64. Currently, there is no cure for FTD. In addition to this, because it affects a younger age group than Alzheimer’s usually does, it becomes extremely distressing for families and often leads to early dependency and care needs.
Lewy Body Dementia
Lewy body dementia (LBD) is marked by abnormal protein deposits in the brain that disrupt both cognitive functions and physical abilities. It causes problems with coordination and balance, vivid visual hallucinations, muscle stiffness, difficulties with concentration, memory issues and severe sensitivity to certain medications.
Due to the symptoms intersecting with other kinds of dementia, it is tricky for doctors to lock down on the diagnosis. Multiple tests are required to diagnose LBD. While there is no cure for this kind of dementia, medical and non-medical treatments such as physical and occupational therapies are recommended to keep symptoms in control as much as possible.
Creutzfeldt-Jakob disease
Creutzfeldt-Jakob disease (CJD) is a rare but devastating brain disorder caused when a type of protein, prions, undergo a change. While the symptoms of CJD are very similar to those of Alzheimer’s, this disease usually gets worse faster and leads to death. Though only one or two cases of CJD are diagnosed per million people around the world, its aggressive progression and lack of a cure make it especially alarming.
Mixed dementia
Mixed dementia is a blend, most often Alzheimer’s disease combined with vascular dementia, and sometimes Lewy body dementia and other types of dementia. This mix leads to overlapping symptoms, and hence, no definitive symptoms are associated with it. A report states that at least one in 10 people with dementia is diagnosed as having mixed dementia. This diagnosis is confirmed only when the doctor finds clear signs of at least two different types of dementia.
Why awareness matters
Alzheimer’s, vascular dementia, Lewy body dementia, frontotemporal dementia, and Creutzfeldt-Jakob disease each have unique causes, symptoms, progression, and treatment responses. Identifying the correct type helps doctors tailor care to individual cases, whether it is medication, lifestyle changes, or managing stroke risk. It also helps families understand what to expect – memory loss vs. personality changes, gradual vs. sudden decline. Without an accurate diagnosis, people may miss out on treatments that could ease symptoms or slow progression.
Awareness is the first step towards better outcomes and quality of life.
Memory loss is just one piece of the dementia puzzle. If you or a loved one is experiencing unexplained behavioural changes, sleep disturbances, or movement issues, talk to a healthcare provider. Dementia isn’t one-size-fits-all, and knowing the differences could change the course of care.
(Dr. Usha Humbi is a consultant neurologist at Narayana Health City, Bengaluru. Usha.humbi.dr@narayanahealth.org)
