The effects of vitamin D deficiency on atherosclerosis status in Saudi Arabia dwellers

Azhar, Wedad (2018) The effects of vitamin D deficiency on atherosclerosis status in Saudi Arabia dwellers. Doctoral thesis (PhD), Manchester Metropolitan University.

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Abstract

Background: Vitamin D has been shown to play a critical role in several systems other than the skeleton system. This study investigates the role of vitamin D in the development and progression of cardiovascular disease, particularly atherosclerosis. Hypothesis: Adequate blood concentrations of vitamin D have a role in preventing atherosclerosis disease and reducing atherosclerosis risk factors. Methods: Participants n=97 aged (Mean±SD) 48.2±8.4 years from both sexes segregated into n=33 controls, n=30 at-risk, and n=34 diagnosed with atherosclerosis. Background characteristics and vitamin D status were assessed from serum 25(OH)D, diet, supplements, and sun exposure. Atherosclerosis status and risk factors were assessed using a combination of clinical records, fasted blood (to ascertain C-reactive protein (CRP), blood glucose (FBG), and lipids profiles) and vascular structural and functional characteristics (including carotid-radial pulse wave velocity (PWV), central-blood pressure (cBP), peripheral-blood pressure (pBP), carotid intima-media thickness (IMT), and carotid inter-adventitial diameter (IAD)). Results: Amongst the participants 51.5% were vitamin D deficient, 25(OH)D <20 ng/mL and 28.9% were insufficient 25(OH)D < 30 ng/mL. 25(OH)D levels were associated with all of the sources of the vitamin (P<0.01). Participants health status displayed distinct values for age, waist-to-hip ratio, CRP, FBG, low-density lipoprotein, triglycerides, pBP, cBP, IMT, and IAD (P<0.05). No association was observed between 25(OH)D concentrations and measured atherosclerosis characteristics in the pooled sample. Indeed, when vitamin D supplements were used 25(OH)D was negatively associated with CRP in the at-risk group and pBP in those diagnosed with atherosclerosis. When supplements were not used 25(OH)D was negatively associated with IMT in the control group (P<0.05). Conclusion: The current study supports the previous reports on the incidence of vitamin D deficiency in Saudi Arabia. However, the current data do not show any link between 25(OH)D and critical to markers of atherosclerosis. Further Longitudinal experimental research is needed to clarify the association.