Prevalence Of Vitamin D Deficiency in Patients Presenting with Acute Coronay Syndrome: An Observational Study

Abstract

Vitamins are essential micronutrients required for maintaining normal physiological functions. Among them, vitamin D is unique as it functions both as a vitamin and a hormone. Vitamin D deficiency has become highly prevalent worldwide, including in India, and has been implicated in several systemic disorders, particularly cardiovascular diseases. Recent evidence suggests that vitamin D deficiency may contribute to the pathogenesis of ACS through endothelial dysfunction, activation of the renin–angiotensin–aldosterone system, and pro-inflammatory mechanisms. However, the association between vitamin D levels and ACS, as well as its relationship with disease severity, remains inconclusive
Background:
Cardiovascular diseases (CVDs), more specifically Acute Myocardial Infarction is considered the leading cause of death globally.
More than 75% of CVD deaths take place in low- and middle-income countries. 38% of premature deaths due to noncommunicable diseases were caused by CVDs.
Traditionally, a number of risk factors have been recognised with regard to development of Myocardial infarction. Several studies done over the last 2 decades have identified new risk factors with potential relevant therapeutic implications. Vitamin D deficiency, amongst others has been the focus of recent interest.
Vitamin D deficiency occurs in 50% of the world’s population. The Prevalence of Vitamin D deficiency in India ranges 50% to 94% and 37% to 99% in community-based and hospital-based studies respectively.(2) The causes for high prevalence of Vitamin D deficiency in Indians is attributed to dark-skin, lack of adequate direct skin exposure to sunlight and lack of vitamin D in predominant Indian diet.
Several recent studies have reported an association between Vitamin D deficiency and Cardiovascular disease; proposed mechanisms being varied. Nuclear Vitamin D receptors have been detected on cardiomyocytes and vascular endothelial cells which could possibly mediate the cardiovascular effects.
Not only is low Vitamin D levels, an independent risk factor for Acute Myocardial Infarction but is also associated with worse outcome; however the causal relationship between the latter needs to be further evaluated.
Considering the therapeutic implications in patients with CAD and its long term benefits if proven, we aimed to study the prevalence of Vitamin D deficiency in patients presenting with ACS; thereby paving the way for future interventional studies.
Aim: To evaluate serum vitamin D levels in patients presenting with acute coronary syndrome and compare them with age- and gender-matched controls, and to assess its association with occurrence and angiographic severity of coronary artery disease.
Materials and Methods:
A comparative case–control study conducted in a tertiary care hospital in Puducherry involving 130 participants, with 65 ACS patients and 65 age- and gender-matched controls. Patients aged >18 years were included after informed consent. Individuals on vitamin D supplementation and those with chronic kidney disease, liver disease, nephrotic syndrome, hypoparathyroidism, or drugs affecting vitamin D metabolism were excluded. About 2 mL of venous blood was collected for estimation of serum 25-hydroxyvitamin D along with routine investigations. Clinical data, including risk factors and coronary angiographic findings, were recorded. Statistical analysis was performed to compare vitamin D levels between groups and assess their association with ACS and number of coronary vessels involved. Multivariate logistic regression was used to identify independent predictors of ACS.
Results: The majority of participants in both groups belonged to the 61–75 years age group, with a male predominance (81.5%). Diabetes mellitus and hypertension were significantly more common among ACS patients compared to controls. The mean serum vitamin D level was lower in ACS patients (21.03 ± 7.29 ng/dL) compared to controls (23.27 ± 6.38 ng/dL), though the difference was not statistically significant. Vitamin D deficiency was more frequent in ACS patients (46.2%) than controls (32.3%). However, no significant association was observed between vitamin D levels and the number of coronary arteries affected. On multivariate logistic regression analysis, vitamin D deficiency was not an independent predictor after adjusting for confounders.
Conclusion: Vitamin D levels were lower in ACS patients than controls, but the difference was not statistically significant. Vitamin D deficiency was not an independent predictor of ACS or coronary vessel involvement after adjustment for confounders.