In a large cohort of French older adults, study findings revealed that blood glucose level was the only cardiometabolic factor with consistently elevated mean levels among patients with dementia compared with controls up to 14 years before diagnosis.
Along with high glycemia, this study also indicated low blood pressure and weight loss as possible targets for managing cardiovascular health in the prevention of dementia among older adults, researchers wrote in JAMA Psychiatry.
“Limited research has examined trajectories of risk factors in the long period preceding dementia diagnosis,” Maude Wagner, MPH, of the Bordeaux Population Health Research Center, Inserm U1219, University of Bordeaux, France, and colleagues wrote. “To our knowledge, no large cohort study has concurrently examined the trajectories of all main cardiovascular risk factors in the years preceding dementia diagnosis, and the optimal targets and time windows in older ages for the management of cardiometabolic health for dementia prevention have remained unclear.”
In this case-control study nested within a French population-based cohort of adults aged 65 years and older, researchers simultaneously modeled and compared the trajectories of cardiometabolic risk factors up to 14 years before dementia diagnosis in those with incident dementia (n = 785) and matched controls (n = 3,140). At diagnosis visit, they matched each dementia case to four controls.
Specifically, the investigators examined the trajectories of cardiometabolic variables through repeated measures of BMI, systolic BP, diastolic BP, HDL cholesterol, LDL cholesterol, triglycerides and glycemia levels between 1999 and 2014.
According to the results, older adults showed faster decline in BMI (P < .001 for group-by-time interaction), slower increase of systolic BP and constantly lower diastolic BP compared with controls. Researchers noted the following measurements 14 years prior to dementia diagnosis, as well as at diagnosis:
- Average BMI: 26.1 at 14 years prior and 24.8 at diagnosis for a case with dementia vs. 25.7 at 14 years prior and 25.3 at diagnosis for a dementia-free control.
- Systolic BP: 135.2 mm Hg at 14 years prior and 142.1 mm Hg at diagnosis for a case vs. 135.8 mm Hg at 14 years prior and 144.9 mm Hg at diagnosis for a control.
- Diastolic BP: 76.5 mm Hg at 14 years prior and 74 mm Hg at diagnosis for a case vs. 76.7 mm Hg at 14 years prior and 75 mm Hg at diagnosis for a control.
Conversely, the results showed that, on average, glycemia was higher among participants with dementia than controls at 14 years prior to diagnosis (89.4 mg/dL vs. 87.1 mg/dL) and at diagnosis (96.4 mg/dL vs. 95.3 mg/dL), with a significant case-control difference from 1.6 to 14 years before diagnosis. However, Wagner and colleagues found no significant case-control differences in the trajectories of blood lipid levels before or at dementia diagnosis.
“In our cohort, blood glucose level was the only cardiometabolic factor with consistently higher mean levels among dementia cases compared with controls up to 14 years prior to diagnosis,” the authors wrote. “Whether confirmed and extended to other populations, these findings emphasizing blood glucose control, low BP and weight loss as key components of cardiovascular health management for primary and secondary prevention of dementia in older persons may have important implications for preventive care practice in geriatric populations.” – by Savannah Demko
Disclosure: The authors report no relevant financial disclosures.