12 lifestyle factors determine 40 percent of dementia cases

A report finds that 12 preventable lifestyle factors determine 40 percent of dementia cases. The Lancet Commission of Dementia Prevention, Intervention, and Care presented new findings on dementia at the 2020 virtual Alzheimer's Association International Conference (AAIC).¹

Alcohol, TBI, air pollution

Some 3 new risk factors were determined to increase dementia risk since the study was first published in 2017.² They include excessive alcohol intake, traumatic brain injury (TBI), and air pollution.

The other 9 factors include not completing secondary education, hypertension, obesity, hearing loss, smoking, depression, physical inactivity, social isolation, and diabetes.

Altogether, these 12 lifestyle factors account for 40 percent of the world’s dementia cases.

Recommendations

Delivered alongside the findings were recommendations for policymakers and individuals who would like to prevent dementia.

Suggestions include:

• Maintaining systolic blood pressure of 130 mm Hg or less in midlife from around age 40 years

• Encouraging the use of hearing aids for hearing loss and reducing hearing loss by protecting ears from high noise levels

• Reducing exposure to air pollution and secondhand tobacco smoke

• Preventing head injury, particularly by targeting high-risk occupations and transport

• Preventing alcohol misuse and limiting drinking to less than 21 units per week (1 unit = 10 ml or 8 g)

• Stopping smoking and supporting individuals to stop smoking

• Providing all children with primary and secondary education

• Leading an active life into midlife and possibly later life

• Reducing obesity and diabetes

It is also important to limit risks of TBI, usually caused by car, motorcycle, and bicycle injuries; military exposures; boxing, horse riding, and other recreational sports; firearms; and falls. Studies that show that TBI is linked with a significantly increased risk for long-term dementia.^3-8

References

1. Livingsoton G, Huntley J, Sommerlad, A, Ames D, Ballard C, Banerjee S, et al. Dementia prevention, intervention, and care: 2020 report of the Lancet Commission. Lancet.

doi: 10.1016/S0140-6736(20)30367-6.

2. Livingston G, Sommerlad, A, Orgeta V, Costafreda SG, Huntley J, Ames D, et al. Dementia prevention, intervention, and care. Lancet. 2017 Dec;390(10113):2673-2734.

2. Fann JR, Ribe AR, Pedersen HS, et al. Long-term risk of dementia among people with traumatic brain injury in Denmark: a population-based observational cohort study. Lancet Psychiatry. 2018 May;5(5):424-431.

3. Nordström A, Nordström P. Traumatic brain injury and the risk of dementia diagnosis: a nationwide cohort study. PLoS Med. 2018 Jan 30;15(1):e1002496.

4. Tolppanen AM, Taipale H Hartikainen S. Head or brain injuries and Alzheimer's disease: a nested case-control register study. Alzheimers Dement. 2017 Dec;13(12):1371-1379.

5. Barnes DE, Byers AL, Gardner RC, Seal KH, Boscardin WJ, Yaffe K. Association of mild traumatic brain injury with and without loss of consciousness with dementia in US military veterans. JAMA Neurol. 2018 Sep 1;75(9):1055-1061

6. Yaffe K, Lwi SJ, Hoang TD, et al. Military-related risk factors in female veterans and risk of dementia. Neurology. 2019 Jan 15;92(3):e205-e211.

7. Redelmeier DA, Manzoor F, Thiruchelvam D. Association between statin use and risk of dementia after a concussion. JAMA Neurol. 2019 May 20;76(8):887-896.