Plasma Parathyroid Hormone Is Associated with Vascular Dementia and Cerebral Hyperintensities in Two Community-Based Cohorts

Abstract

In two community-based samples, PTH predicted clinically diagnosed vascular dementia as well as neuroimaging indices of cerebral small vessel disease. Our data suggest a role for PTH in the development of vascular dementia.

Parathyroid Hormone and Subclinical Cerebrovascular Disease: The Atherosclerosis Risk in Communities Brain Magnetic Resonance Imaging Study

“…In contrast to Hagström et al 17 , we did not observe any association of PTH with subclinical cerebrovascular disease after adjustment for CVD risk factors and 25(OH)D levels. Prior work in the ARIC Brain MRI study has found that cumulative systolic blood pressure was a strong predictor of WMH progression over follow-up, 19 and since PTH is associated with incident hypertension, 3 we had hypothesized that hypertension might be a mediator in the biologic pathway between elevated PTH levels and cerebrovascular disease.…”

“…Although our study sample was much larger than the one in the previously published paper by Hagström et al 17 (n=1703 in our sample vs n=406 in their study), our study may still be underpowered for prospective analyses as mentioned above. Because the sample was relatively young at the time of both brain MRIs, most participants had relatively minimal WMH, with relatively low rates of infarcts at both MRIs.…”

“…This study by Hagström et al was conducted in the Uppsala Longitudinal Study of Adult Men (ULSAM) and the PIVUS cohorts, which are populations of white race in Sweden. 17 The authors found that PTH was associated with both vascular dementia in ULSAM as well as increased WMH on brain MRI in PIVUS. These associations remained statistically significant even after adjustment for CVD risk factors and markers of mineral metabolism such as 25(OH)D levels.…”

“…In PIVUS, there was only a one-time brain MRI performed that was 5 years after the PTH measurement, with no baseline brain MRI to examine white matter progression. 17 Other limitations of that study are the inability to generalize to younger populations or other race/ethnicities. In our study, we had a baseline brain MRI and a second brain MRI 10 years later to observe for white matter progression.…”

“…17 In the PIVUS study, the association of PTH with WMH remained significant even after adjustment for 25(OH)D. However, the PIVUS study was small (n=406), studied an older population (all age 70) that was only of white race, and had a brain MRI measurement at only one point in time, which warrants further exploration using the biethnic ARIC study. To our knowledge, no prior study has evaluated the prospective association of PTH with white matter changes in the brain on serial MRI studies.…”