Cardiovascular disorders:
Vitamin D receptors and its metabolizing enzymes are present in the
whole cardiovascular system (67). The VDR knock-out mice showed severe
impairments in cardiovascular system including cardiac hypertrophy (68).
Many observational studies and results of meta-analyses showed vitamin D
deficiency is associated with the cardiovascular disorders (69, 70, 71,
72, 73). The studies to probe the association of vitamin D deficiency
with cardiovascular events in Pakistani population are very few. A study
conducted in patients with first acute myocardial infarction (AMI)
showed association between vitamin D deficiency and a genetic variant in
the vitamin D binding protein with this event (74). However, another
study conducted to evaluate the role of vitamin D and calcium deficiency
with hypertension showed weak correlation of these two factors with
mean, systolic and diastolic blood pressures (75).
Vitamin D deficiency was also studied with the relevance of cardio
metabolic syndrome and found that it was significantly associated with
hypertension in Pakistani population (76). High levels of parathyroid
hormone (PTH) could be responsible for the development of hypertension
(77, 78). One study conducted in Pakistani population showed that PTH
levels were significantly associated with variation (R990G) of calcium
sensing gene in the vitamin D deficient subjects (79). However, blood
pressure was not monitored in this study.