Dementia: Types, Symptoms, Risk Factors — and Differences Between Men and Women

Dementia is often described as age-related memory loss. Medically, however, it refers to a group of different brain diseases with distinct causes, courses, and symptom profiles.

Everyone knows the term Alzheimer’s Disease. But which other types of dementia exist?Which risk factors favor the development of the disease? How does the gender data gap come into play? Here, you will find answers to these questions … and more.

Dementia: If So, How Many?

The term “dementia” comes from Latin and was already used in antiquity to describe mental confusion. It is composed of de (“away, down”) and mens (“mind, intellect, thinking ability”). Literally translated, dementia therefore means something like “decline of the mind” or “loss of mental abilities.”

This origin of the term corresponds remarkably well with today’s medical definition: dementia does not describe a normal aging process, but a pathological decline of mental functions on several levels. Different underlying causes lead to different symptom patterns and disease courses.

Today, several forms of dementia are distinguished:

·       Alzheimer’s Disease: The Most Common Form

In Alzheimer’s disease, two pathological protein changes are central: deposits of amyloid-β (plaques) outside nerve cells and tau changes (neurofibrils) inside nerve cells. These processes are associated with synapse loss, inflammatory reactions, and progressive death of nerve cells.

Typical symptoms: Alzheimer’s often begins gradually with short-term memory impairment (learning new information becomes difficult), word-finding problems, and disorientation. As the disease progresses, impairments in daily functioning, planning and judgment, and sometimes behavioral or personality changes occur (DeTure & Dickson, 2019).

Differences between men and women: In population data, women at older ages are diagnosed with Alzheimer’s more frequently than men. One reason may be hormonal changes during menopause (Ferretti et al., 2018).

Women with the same Alzheimer pathology can remain “inconspicuous” longer in verbal memory tests or compensate for deficits for a longer time. This may contribute to Alzheimer’s being detected later in women on average — even though the underlying pathology may be equally advanced (Sundermann et al., 2017).

Relevant and modifiable risk factors: Several modifiable factors are considered important for overall dementia risk, including high blood pressure, diabetes, physical inactivity, depression, social isolation, and hearing loss, which we will address in more detail shortly (Livingston et al., 2020).o

·       Vascular Dementia: Vascular Damage in Focus

In vascular dementia, vascular and circulatory disorders are central. Small (sometimes unnoticed) infarcts, microbleeds, or chronic reduced blood flow can damage brain tissue, especially white matter and the connections between brain regions. As a result, thinking processes become “slower” and less efficient.

Typical symptoms: Common features include slowed thinking, attention and executive function problems (planning/organizing), gait instability, and — depending on vascular events — a rather stepwise course (Iadecola, 2013).

Differences between men and women: Vascular risks develop differently over the course of life, which can influence the timing and type of clinical manifestation. And because medicine knows more about men than about women, a gender data gap can also affect prevention and diagnosis here (Iadecola, 2013; Livingston et al., 2020).

Risk factors for men and women are similar to those in Alzheimer’s, although high blood pressure and vascular diseases occur more frequently in men. (Yes, we too refer to the “average man.”)

·       Lewy Body Dementia (DLB): Symptoms That Are Difficult to Classify

For reasons not yet fully clarified, Lewy body dementia involves misfolding of the protein alpha-synuclein, which accumulates in nerve cells and gradually disrupts key brain functions, particularly attention, visual processing, and sleep-wake regulation.

Typical symptoms: Years before other symptoms appear, REM sleep disturbances may occur. Very early on, fluctuations in cognitive performance, attention problems, and visual hallucinations are common. Parkinson-like movement disorders may occur in parallel but often develop later. Loss of smell and disturbances of autonomic regulation such as dizziness when standing up, constipation, excessive sweating, or blood pressure fluctuations can be risk factors for the disease, but also early symptoms of the disease itself (Walker et al., 2015). This makes diagnosis correspondingly complex.

Differences between men and women: This form is diagnosed more frequently and more quickly in men. Women more often show pronounced hallucinations and are therefore sometimes initially classified in a psychiatric context (Chiu et al., 2023).

·       Parkinson’s Disease Dementia (PDD): Movement Disorder With Cognitive Consequences

As in Lewy body dementia, Parkinson’s dementia involves misfolding of alpha-synuclein. The crucial difference, however, lies in where the process begins: initially, deeper brain regions such as the substantia nigra, which are responsible for movement control, are affected. Only later does the pathology spread to brain regions that control attention, thinking, and perception.

Typical risk factors and symptoms: For years, classic Parkinson’s symptoms dominate: tremor, muscle rigidity, slowed movements, and gait instability. Only later do cognitive changes appear, mostly in the form of attention, planning, and memory problems. Sleep disturbances, particularly related to REM sleep behavior disorder, are also common. Loss of smell and autonomic abnormalities such as blood pressure fluctuations, constipation, or dizziness can be present long before cognitive symptoms (Walker et al., 2015).

Differences between men and women: Parkinson’s disease occurs more frequently in men, and accordingly Parkinson’s dementia is also diagnosed more often in men. At the same time, cognitive decline is often long interpreted as “part of Parkinson’s” and not recognized as a separate form of dementia. Here, too, the gender data gap can play a role in how symptoms are perceived and evaluated (Chiu et al., 2023).

·       Frontotemporal Dementia (FTD): Classifying Behavioral Changes

In frontotemporal dementia, nerve cells die primarily in the frontal and temporal lobes. Unlike in Alzheimer’s disease, the memory centers are not affected at first, but rather brain areas that control personality, social behavior, impulse control and — in so-called primary progressive aphasia (PPA) — language. The cause is misfolded proteins, usually tau or TDP-43, which accumulate in nerve cells and impair their function.

Typical symptoms: At first, disinhibition, tactlessness, reduced empathy, apathy, or noticeable decision-making and impulse patterns are often observed. Memory problems are frequently not the main feature at the beginning. Instead, word-finding problems, altered speech melody, or difficulties understanding spoken language may become apparent (Bang et al., 2015).

Differences between men and women: Clinical analyses show that manifestations can be distributed differently between men and women. The behavior-focused variant (bvFTD) is observed more often in men, while language-focused courses (PPA) are described more frequently in women (Pengo et al., 2022). These different “entrances” can influence which medical specialty is first consulted (neurology, psychiatry, speech therapy) and may contribute to misclassification as a psychological or interpersonal problem (Zapata-Restrepo et al., 2021).

Risk factors: Classic vascular or metabolic risks play a minor role here. Compared with other forms, FTD is more strongly characterized by genetic and cellular biological processes. Direct influence on these factors is not possible (Bang et al., 2015).

·       Mixed Dementia: Several Disease Processes Overlapping

In mixed dementia, several pathological changes are present in the brain at the same time. The most common combination is Alzheimer-type protein deposits (amyloid and tau) together with vascular damage due to circulatory disorders, microinfarcts, or vascular changes. Studies show that such mixed patterns are more the rule than the exception at older ages (Schneider et al., 2007).

Typical symptoms: Symptoms often appear “inconsistent” and do not clearly fit a single dementia form. Memory problems as in Alzheimer’s can mix with slowed thinking, gait instability, or pronounced attention problems typical of vascular damage. This mixture makes clinical classification more difficult.

Differences between men and women: Neuropathological analyses show that mixed pathologies can be distributed differently between men and women. Combinations of Alzheimer and vascular changes were described more often in women, while other pathological patterns dominated in men. These differences are subtle but may explain why symptoms present and are evaluated differently between the sexes (Barnes et al., 2019).

Risk factors: Both Alzheimer’s and vascular dementia risk factors apply. Particularly important are high blood pressure, diabetes, physical inactivity, vascular diseases, and hearing loss. Because several processes act simultaneously, prevention of vascular risks is especially relevant (Livingston et al., 2020).

Hearing Loss: Loneliness and Cognitive Burden

Untreated hearing loss is, as mentioned, one of the most important modifiable dementia risk factors. Over time, it can lead to increased cognitive load, social withdrawal, loneliness, and ultimately reduced neuronal stimulation.

Long-term data from Johns Hopkins University (Lin et al., 2011) show this connection clearly: Because older men tend to use hearing aids less frequently at an early stage of hearing loss (vanity?), while women more often live alone later in life, poor hearing can contribute to the development of dementia in multiple ways.

Why Diagnostics Do Not Work Equally for Everyone

For a long time, the higher Alzheimer rate in women was explained solely by the fact that women live longer. But this explanation falls short. Women not only have more time to develop the disease — they also partly have different biological conditions that influence the responsible processes.

Studies show that hormonal factors, vascular health, metabolic processes, immune activity, and even educational biography play a role in the development of dementia. A higher level of education, for example, can mean increased cognitive flexibility, which can reduce disease risk (Stern, 2012).

Multifactorial and Complex: Not All Dementia Is the Same

Dementia forms differ from one another. At the same time, studies show that symptoms, risk courses, and diagnostics do not progress identically in men and women.

These differences significantly influence when and how dementia is recognized.

But how does diagnosis work? And how should one act after the diagnosis? Answers to these questions will follow in our next article. Until then, we answer a few other questions …

FAQ – Frequently Asked Questions About Dementia

1. Why do relatives often notice changes earlier than patients?

Early dementia processes often impair self-perception and insight. Outsiders therefore notice subtle changes earlier.

2. Why does dementia occur in some people despite a healthy lifestyle?

In addition to lifestyle factors, genetic predispositions, aging processes, previous head injuries, and complex protein changes in the brain play a role. A healthy lifestyle reduces risk but does not provide absolute protection.

3. Why are social contacts considered a protective factor for the brain?

Social interaction challenges the brain in a complex way: language, emotion, memory, and attention are activated at the same time. Social isolation, on the other hand, increases dementia risk.

4. Can mental training such as puzzles or memory games prevent dementia?

Such exercises strengthen cognitive reserve and can delay progression, but they do not replace physical activity, metabolic health, and social engagement.

Further information on dementia (and many other topics) can be found not only on the blog but also in the volumes of our “Codex Humanus” and the “Medizinskandale” series. Feel free to visit our online shop.

Sources:

·       DeTure, M. A.; Dickson, D. W. (2019): “The neuropathological diagnosis of Alzheimer’s disease,” Molecular Neurodegeneration.

·       Ferretti, M. T. et al. (2018): “Sex differences in Alzheimer disease — the gateway to precision medicine,” Nature Reviews Neurology.

·       Sundermann, E. E. et al. (2017): “Does the female advantage in verbal memory contribute to underestimating Alzheimer’s disease pathology in women versus men?,” Journal of Alzheimer’s Disease.

·       Livingston, G. et al. (2020): “Dementia prevention, intervention, and care: 2020 report of the Lancet Commission,” The Lancet.

·       Iadecola, C. (2013): “The pathobiology of vascular dementia,” Neuron.

·       Walker, Z. et al. (2015): “Lewy body dementias,” The Lancet.

·       Chiu, Y. C. et al. (2023): “Sex differences in clinical features of dementia with Lewy bodies: a systematic review,” Journal of Neurology.

·       Bang, J. et al. (2015): “Frontotemporal dementia,” The Lancet.

·       Pengo, M. F. et al. (2022): “Sex differences in frontotemporal dementia clinical phenotypes,” Neurology.

·       Zapata-Restrepo, L. M. et al. (2021): “The Psychiatric Misdiagnosis of Behavioral Variant Frontotemporal Dementia,” Frontiers in Neurology.

·       Schneider, J. A. et al. (2007): “Mixed brain pathologies account for most dementia cases in community-dwelling older persons,” Neurology.

·       Barnes, L. L. et al. (2019): “Sex differences in mixed neuropathologies in dementia,” Brain.

·       Lin, F. R. et al. (2011): “Hearing loss and incident dementia,” Archives of Neurology.

·       Stern, Y. (2012): “Cognitive reserve in ageing and Alzheimer’s disease,” The Lancet Neurology.