Dementia and the Seasons

Seasonal changes have been linked with a number of illnesses. For example, Seasonal Affective Disorder, also known as SAD, is a type of depression that occurs during the winter months, when people’s exposure to the sun is limited due to the shorter days.

It has also been shown that schizophrenia is most likely to begin to show symptoms during the winter months. Other studies have demonstrated that seasonal variation affects memory as well as the ability to concentrate.

Researchers from Canada’s Sunnybrook Health Sciences Centre and University of Toronto set out to determine whether dementia might also be subject to seasonal variation.

The study, published in PLOS Medicine, examined data from thousands of elderly people in the United States, Canada and France. Some but not all had already been diagnosed with some form of dementia.

All the subjects underwent extensive neuropsychological testing, as well as testing for levels of Alzheimer’s-related proteins.

The results of the research made it clear that average cognitive function was better during the summer and fall than during the winter and spring. In fact, the difference between cognitive function during the two sets of seasons was calculated to be the equivalent of 4.8 years of normal cognitive decline.

It was also noted that during the colder months, participants were more than 30% more likely to be diagnosed with some form of dementia.

The researchers controlled for a wide range of factors that could have influenced their results, for example: SAD, sleep quality, differing levels of physical activity in different season. The results remained statistically significant.

Another significant finding related to specific Alzheimer’s proteins. Researchers found that the levels of these proteins in the cerebrospinal fluid also fluctuated across seasons.

The conclusion: symptoms of dementia in the elderly population worsen during the colder months.

The question for us is how to handle the growing body of research which demonstrates that the winter months have a significant negative impact on our general health, and in particular on cognitive aspects of our health.

It has already become common to install full spectrum light bulbs in the house during the winter months in order to avoid SAD. As more details come in about the reasons for these seasonal declines, there will no doubt be more recommendations for how to minimize them.

While the study offers hope for the future, those suffering the debilitating effects of Alzheimer’s right now can find hope at the Memory Care Unit of Hamilton Grove Healthcare and Rehabilitation Center, in Hamilton, NJ.

we are experts in handling all levels of cognitive impairment, from mild cognitive impairment to Alzheimer’s and other dementias.

We have created a unique environment and care program specifically designed to address the needs of this population. Our Alzheimer’s Unit is situated in a separate, secure wing to ensure the safety and well-being of our residents. It offers a structured daily routine, mind-stimulating activities, excellent social interaction, with optimal patient independence in a calm and soothing atmosphere.

Read our reviews on,, and to hear what our residents and their families have to say.

Or better yet, come see for yourself: Contact us to schedule a tour by calling 609-588-5800 or by clicking here.

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