WHO adds seven new risk factors to dementia guidance

GENEVA — The World Health Organization has expanded its list of risk factors for cognitive decline and dementia, adding seven new entries to the existing 12-factor guideline. The previously identified factors included low cognitive activity, limited social engagement, physical inactivity, excessive alcohol consumption, tobacco use, unhealthy diet, obesity, diabetes, hypertension, lipid disorders, hearing loss and depression. The newly added risks are stroke, traumatic brain injury, vision impairment, sleep disorders, HIV, air pollution and postmenopausal hormone therapy. WHO said stroke and other cardiovascular conditions can affect brain health and raise dementia risk, while mild head trauma may contribute to mood, depression and anxiety problems with broader life impacts. Experts pointed to evidence that sleep supports the brain's waste-clearing processes and that disorders like sleep apnea can trigger changes similar to those seen in Alzheimer's disease. The organization noted that untreated HIV affects the central nervous system and is linked to virus-associated cognitive impairment, and cited research showing long-term exposure to air pollution, particularly fine particulate matter, is associated with cognitive decline and dementia. WHO also recommended against using postmenopausal hormone therapy to prevent dementia in women over 65, citing insufficient evidence of benefit, and said data on the effect in younger women remain inconclusive.