Calcium Effects on Vascular Endpoints
Calcium Effects on Vascular Endpoints
The effect of calcium supplementation on arterial calcification is unclear. Post-trial coronary artery calcification (CAC) measurements using cardiac CT were similar in women randomized to calcium/vitamin D supplementation (calcium/D) and those receiving placebo. Treatment with moderate doses of calcium plus vitamin D3 did not appear to alter coronary artery calcified plaque burden among postmenopausal women.
In subjects new to hemodialysis, baseline CAC (coronary artery calcification) score is a significant predictor of all-cause mortality. Use of calcium-containing phosphate binders in patients new to hemodialysis is associated with a rapidly progressive increase in the extent of CAC with resultant higher mortality. Total body calcium score and progression of CAC score in predialysis patients was shown to be higher with the use of calcium containing phosphate binders versus non calcium containing phosphate binders. Calcium supplementation can hypothetically increase arterial calcification and cardiovascular events, so calcium supplements should be used with caution in patients with renal disease. People with impaired renal function who take calcium supplements may be at higher risk of cardiovascular problems.
Relationship between calcium intake/supplementation and blood pressure or risk of hypertension is unclear. The Women's Health Initiative study revealed that over a median follow-up time of 7 years, there was no significant difference in the mean change over time in systolic blood pressure (0.22 mm Hg, 95% CI -0.05 - 0.49 mm Hg) and diastolic blood pressure (0.11 mm Hg, 95% CI -0.04 - 0.27 mm Hg) between the active and placebo treatment groups. In postmenopausal women, calcium plus vitamin D3 supplementation did not reduce either blood pressure or the risk of developing hypertension over seven years of follow up.
A prospective cohort study of 28,886 US women aged 45 years, revealed that intakes of low-fat dairy products, calcium, and vitamin D were each inversely associated with risk of hypertension in middle-aged and older women, suggesting their potential roles in the primary prevention of hypertension and cardiovascular complications during 10 years of follow-up. This study was limited to white women.
Limited data is available in regards to calcium intake/supplementation on lipid profile. RCT of supplementation of calcium citrate in normal older women showed beneficial changes in circulating lipids in post-menopausal women. After 12 months, HDL cholesterol levels and the HDL cholesterol to LDL cholesterol ratio had increased more in the calcium group than in the placebo group. This was largely due to a 7% increase in HDL cholesterol levels in the calcium group, with a non-significant 6% decline in LDL cholesterol levels. There was no significant treatment effect on triglyceride level. Calcium possibly binds to fatty acids and bile acids in gut resulting in poor fat absorption. Other possible mechanism include increased lipolysis as a result of inhibition of PTH and 1, 25 (OH)2 Vitamin D.
The available evidence on the role of calcium supplementation in the development of diabetes is limited, but a systematic review and meta-analysis suggests that combined vitamin D and calcium supplementation may have a role in the prevention of T2DM only in populations with glucose intolerance, who are at high risk of developing diabetes.
Calcium Supplementation and Arterial Calcification
The effect of calcium supplementation on arterial calcification is unclear. Post-trial coronary artery calcification (CAC) measurements using cardiac CT were similar in women randomized to calcium/vitamin D supplementation (calcium/D) and those receiving placebo. Treatment with moderate doses of calcium plus vitamin D3 did not appear to alter coronary artery calcified plaque burden among postmenopausal women.
In subjects new to hemodialysis, baseline CAC (coronary artery calcification) score is a significant predictor of all-cause mortality. Use of calcium-containing phosphate binders in patients new to hemodialysis is associated with a rapidly progressive increase in the extent of CAC with resultant higher mortality. Total body calcium score and progression of CAC score in predialysis patients was shown to be higher with the use of calcium containing phosphate binders versus non calcium containing phosphate binders. Calcium supplementation can hypothetically increase arterial calcification and cardiovascular events, so calcium supplements should be used with caution in patients with renal disease. People with impaired renal function who take calcium supplements may be at higher risk of cardiovascular problems.
Calcium Supplementation and Blood Pressure
Relationship between calcium intake/supplementation and blood pressure or risk of hypertension is unclear. The Women's Health Initiative study revealed that over a median follow-up time of 7 years, there was no significant difference in the mean change over time in systolic blood pressure (0.22 mm Hg, 95% CI -0.05 - 0.49 mm Hg) and diastolic blood pressure (0.11 mm Hg, 95% CI -0.04 - 0.27 mm Hg) between the active and placebo treatment groups. In postmenopausal women, calcium plus vitamin D3 supplementation did not reduce either blood pressure or the risk of developing hypertension over seven years of follow up.
A prospective cohort study of 28,886 US women aged 45 years, revealed that intakes of low-fat dairy products, calcium, and vitamin D were each inversely associated with risk of hypertension in middle-aged and older women, suggesting their potential roles in the primary prevention of hypertension and cardiovascular complications during 10 years of follow-up. This study was limited to white women.
Calcium and Lipids
Limited data is available in regards to calcium intake/supplementation on lipid profile. RCT of supplementation of calcium citrate in normal older women showed beneficial changes in circulating lipids in post-menopausal women. After 12 months, HDL cholesterol levels and the HDL cholesterol to LDL cholesterol ratio had increased more in the calcium group than in the placebo group. This was largely due to a 7% increase in HDL cholesterol levels in the calcium group, with a non-significant 6% decline in LDL cholesterol levels. There was no significant treatment effect on triglyceride level. Calcium possibly binds to fatty acids and bile acids in gut resulting in poor fat absorption. Other possible mechanism include increased lipolysis as a result of inhibition of PTH and 1, 25 (OH)2 Vitamin D.
Calcium and Diabetes
The available evidence on the role of calcium supplementation in the development of diabetes is limited, but a systematic review and meta-analysis suggests that combined vitamin D and calcium supplementation may have a role in the prevention of T2DM only in populations with glucose intolerance, who are at high risk of developing diabetes.
