Avoid three midlife risks: 13 years

NYU Langone-led researchers reported on August 5 that three familiar midlife vascular risks — smoking, diabetes and high blood pressure — were tied to a large gap in how long people lived without dementia. The study, published in *Neurology Open Access*, followed 12,409 U.S. adults for a median of 26.3 years and estimated dementia-free survival from age 55 to 95. Participants with none of the three risks lived an average 30.1 years without dementia, compared with 17.5 years for those with all three. The paper was observational, and the authors said it showed an association rather than proof that changing those risks would itself prevent dementia. ### Which three risks were counted in the study? The study defined the three risks at a midlife visit in 1990-1992 as current smoking, diabetes, and hypertension. Hypertension meant blood pressure of at least 140/90 mmHg or use of blood-pressure medication; diabetes was identified by self-report, medication use or HbA1c of 6.5% or higher. (neurology.org) The age window matters because the researchers examined adults who were alive and dementia-free at age 55 and used midlife vascular status to estimate later dementia-free years. NYU Langone said the findings applied to maintaining normal blood pressure, avoiding diabetes and not smoking from roughly age 48 to 68. (neurology.org) ### Where does the “nearly 13 years” figure come from? The 12.6-year estimate came from comparing people with zero of the three risk factors against people with all three. In the paper, dementia-free survival declined stepwise as vascular risk burden rose, from 30.1 years for zero risks to 17.5 years for three risks. During follow-up through 2022, 3,008 participants developed dementia and 5,238 died without developing dementia. (nyulangone.org) The authors said the highest-risk group faced both more dementia and more competing mortality, which shortened overall dementia-free survival. ### Does this mean controlling those risks will prevent dementia? The American Academy of Neurology said the study does not prove that avoiding the three vascular risks causes a delay in dementia; it shows an association. (neurology.org) That caution is important because risk factors were assessed once, so the analysis did not track how changes in smoking, blood pressure or diabetes status over time altered outcomes. Josef Coresh of NYU Grossman School of Medicine said in the academy release that the findings support preventing those risk factors in midlife “as a strategy for delaying the onset of dementia and maintaining brain health.” The paper itself said expressing vascular risk in years rather than percentages may offer a more patient-centered way to discuss prevention. (aan.com) ### Were the results the same for everyone? Women in the cohort lived longer without dementia than men at the same risk level, according to the paper. Among participants with all three risk factors, women averaged 18.1 dementia-free years versus 16.6 years for men. Black participants had shorter dementia-free survival than White participants under similar risk conditions. (aan.com) Among those with all three risk factors, White participants averaged 19.6 dementia-free years without dementia, compared with 16.0 years for Black participants. ### Why are doctors likely to use this framing? The paper called dementia-free survival a “patient-centered outcome” that can help with shared goal-setting. (neurology.org) That framing turns a prevention message into a time-based estimate that primary-care doctors can use when discussing smoking cessation, blood-pressure control and diabetes prevention in midlife. Healio, citing the paper and the AAN release, said the findings support preventive measures targeting those three vascular risks. The underlying study used data from the long-running Atherosclerosis Risk in Communities study, which began in 1986 and continued dementia surveillance through 2022. ### What comes next for this research? (neurology.org) The August 5 paper leaves open whether repeated measurement of vascular risks, rather than a single midlife snapshot, would change the estimates. The authors identified that one-time assessment as a study limitation. The next step is likely to come in follow-up analyses from the ARIC cohort or other long-running studies that test whether improving blood pressure, smoking status or diabetes control over time changes dementia-free survival. (healio.com) For now, the published record is the August 5 *Neurology Open Access* paper by Jiaqi Hu, Josef Coresh and co-authors using ARIC data through 2022. (neurology.org) (aan.com)