Left ventricular hypertrophy linked to cognitive impairment
Individuals with left ventricular hypertrophy (LVH) are at increased risk of cognitive impairment, an effect observed in both the general population and hypertensive individuals, according to a meta-analysis.
Researchers searched multiple electronic databases for studies assessing the association between LVH and cognitive function. A total of 18 cross-sectional or prospective studies reporting a positive association between LVH and cognitive impairment or cognitive performance and decline in population-based or patient-based samples were analysed using random-effects and meta-regression models.
Pooled data revealed that the risk of cognitive impairment was elevated among individuals with LVH in population-based studies (nine studies; sample, n=28,648; odds ratio (OR), 1.40; 95 percent CI, 1.18 to 1.66) and studies in hypertensive patients (three studies; sample, n=1,262; OR, 2.14; 1.39 to 3.30). The association was stronger when assessing LVH by echocardiography than by electrocardiogram.
Results were robust in the sensitivity analyses of prospective and highest quality studies, as well as of those adjusting for hypertension or blood pressure levels. No heterogeneity or publication bias was documented.
LVH is said to occur as a compensatory adjustment of the heart muscle to chronic pressure load, reducing wall stress and maintaining adequate stroke volume. While multifactorial and complex, the pathogenic mechanism of the event includes both neurohormonal responses and genetic predisposition. [J Hypertens 2011;29:17–26]
Considered a target organ damage in hypertension, LVH has been associated with concurrent vascular damage in the kidney and retina. This said and in light of the effect of high blood pressure on cerebral circulation and cognition, the present data may underlie a generalized effect of chronic hypertension on both the heart and brain, researchers said. [Am J Physiol Heart Circ Physiol 2013;304:H1598–H1614]