Frailty Modifies the Association of Hypertension With Cognition in Older Adults: Evidence From the ELSI-Brazil.

BACKGROUND: The relationship between hypertension and cognition in later life is controversial. We investigated whether the association of hypertension with cognition differs in older adults according to the frailty status using cross-sectional data from the Brazilian Longitudinal Study of Aging, a nationally representative sample of adults aged ≥50 years. METHOD: Hypertension was defined by a medical diagnosis or measured blood pressure ≥140/90 mm Hg. Frailty status was assessed using the Cardiovascular Health Study criteria. We estimated the association of hypertension and systolic and diastolic blood pressure with global cognition, orientation, memory, and verbal fluency z-scores, using multiple linear regression models. We also investigated interactions between hypertension and frailty on cognitive performance and impairment. RESULTS: We evaluated 8609 participants (mean age = 61.9 ± 9.6 years, 53% women). Participants with hypertension (59% of adults aged 50-64 and 77% of those aged ≥65 years) had poorer scores for global cognitive performance than those without hypertension, especially among adults aged 50-64 years (ß = -0.09; 95% confidence interval = -0.15, -0.04; p = .001). However, frailty modified the associations of hypertension with cognitive performance and impairment in those aged ≥65 years (p-values for interaction = .01 and .02, respectively). Among nonfrail older adults, hypertension was associated with cognitive impairment. In contrast, among frail older adults, hypertension was related to better global and memory cognitive z-scores. CONCLUSIONS: Hypertension was associated with worse cognitive performance. Among older adults, hypertension was related to cognitive impairment only in nonfrail participants. Frailty evaluation may help clinicians offer personalized hypertension management in older adults.

Does undiagnosed diabetes mitigate the association between diabetes and cognitive impairment? Findings from the ELSI-Brazil study.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is associated with cognitive impairment. However, most of the evidence has been based on self-reported T2DM, and undiagnosed diabetes has not been considered as a separate category. We aimed to examine the extent to which undiagnosed diabetes modifies the association between diabetes and cognitive impairment in a representative sample of Brazilian adults aged 50 years and older. METHODS: We analyzed baseline data from 1944 participants of the Brazilian Longitudinal Study of Aging (ELSI-Brazil) conducted from 2015 to 2016. Diabetes was evaluated based on self-reported doctor diagnosis and glycosylated hemoglobin levels. Participants were classified as diabetics (D), undiagnosed diabetics (UDD), or nondiabetics (ND). Cognitive function was assessed by word list learning and verbal fluency tests. Three multiple logistic regression models were used to evaluate the changes in the strength of the associations. RESULTS: Participants with diabetes had 49% greater odds of exhibiting impaired memory than nondiabetics (odds ratio [OR] = 1.49; 95% CI: 1.01-2.20). By combining UDD and ND, the association between diabetes and impaired memory was attenuated by 2.0%, losing its statistical significance (OR = 1.46; 95% CI: 0.98-2.17). By combining UDD and D, the association was attenuated by 7.4% (OR = 1.38; 95% CI: 1.01-1.90). No significant association was found between T2DM and impaired verbal fluency. CONCLUSION: This study found an association between T2DM and impaired memory but not with impaired verbal fluency. When UDD individuals are considered diabetics, this association is attenuated; when UDD individuals are considered as ND, this association is attenuated to the extent that it loses its statistical significance, affecting thus the clinical interpretation.