Prevalence and trends of cognitive decline in Spain
Spain is ageing rapidly. In 2026, more than 20% of the population is over 65, a figure projected to reach 30% by 2050. Cognitive decline is growing in parallel: the most recent studies estimate that dementia prevalence will double over the next two decades without large-scale preventive measures. This growth is not purely demographic — it also reflects improved diagnostic capacity and growing social awareness of a problem that was historically hidden.
Mild cognitive impairment (MCI) affects a significant share of older adults without reaching the threshold of dementia. However, between 10% and 15% of people with MCI progress to dementia each year, making this stage a critical window for intervention. Detecting and intervening at this phase — through cognitive stimulation, physical exercise, cardiovascular risk factor management, and maintenance of social activity — is key to slowing the progression of decline and preserving the patient's autonomy.
Autonomous communities such as Castilla y León, Asturias, and Extremadura, which have the highest ageing rates, also show the highest prevalence figures. Nevertheless, underdiagnosis cuts across all regions, particularly in rural areas with limited access to neurology or geriatrics specialists, where dementias are often identified only at advanced stages.
The role of social isolation and conversation in cognitive health
The scientific evidence is robust: social isolation is a modifiable risk factor for cognitive decline. The 2024 Lancet Commission includes it among 14 factors that, if addressed, could prevent or delay up to 45% of dementia cases. Older adults who engage in frequent conversations, take part in social activities, and feel heard show a slower cognitive trajectory. Conversely, chronic loneliness accelerates brain atrophy and increases dementia risk by up to 40%.
In Spain, many older adults go days without a meaningful conversation. This lack of daily verbal and cognitive stimulation has direct consequences for memory, language, and executive function. Every conversation activates neural circuits related to attention, comprehension, working memory, and language production — functions that deteriorate more rapidly when they remain inactive.
Interventions based on conversational companionship, whether in person or by phone, have shown measurable benefits in recent clinical studies. Hermet was built on this very evidence: offering personalised, everyday conversations to older adults as a form of cognitive stimulation and emotional connection, complementing existing formal and informal care.
Challenges in diagnosis, care, and the burden on families
Late diagnosis of dementia is one of the most serious problems in the Spanish healthcare system. On average, two to three years elapse between the first symptoms and formal diagnosis. This delay limits the effectiveness of available pharmacological and non-pharmacological interventions and places a greater burden on informal caregivers. Furthermore, late diagnosis deprives patients of the opportunity to plan their future and make informed decisions about their care.
Families absorb the bulk of care: 80% of dementia care in Spain is provided by family members, the majority of them women aged between 50 and 65. The impact on caregivers' mental health is significant: more than 40% show symptoms of anxiety or depression, according to IMSERSO, and so-called 'caregiver burnout syndrome' affects a growing proportion of this population. Supporting both the patient and their family environment is essential to sustaining the care system over the long term.
Prevention and new intervention strategies
The latest research has transformed the understanding of cognitive decline: once considered an inevitable consequence of ageing, it is now seen as a process in which multiple modifiable risk factors play a decisive role. The Lancet Commission estimates that up to 45% of dementia cases could be prevented or delayed by acting on factors such as hypertension, hearing loss, depression, physical inactivity, and social isolation. Spain, with one of the highest ageing rates in Europe, has much to gain from adopting an ambitious preventive approach.
In the technology space, tools like Hermet represent a new generation of preventive interventions based on daily conversation. By providing personalised verbal stimulation, early detection of changes in language and memory, and a constant emotional bond, these services complement the work of healthcare professionals and families, helping keep the mind active and spotting warning signs that might otherwise go unnoticed.