New research reveals that patients with lupus are more likely to develop metabolic syndrome and insulin resistance, both of which are associated with heart disease if they have lower levels of vitamin D.
The study, led by experts from the University of Birmingham and the University of Manchester and published in Rheumatology, examined vitamin D levels in 1,163 lupus patients across 33 centers in 11 countries. The findings suggest that boosting vitamin D levels may help control cardiovascular risk factors and improve long-term outcomes for those with systemic lupus erythematosus (SLE).
Dr. John A Reynolds, Clinical Senior Lecturer in Rheumatology at the University of Birmingham and co-author of the report noted, “Our results indicate that co-existing physiological abnormalities may contribute to long-term cardiovascular risk early on in SLE. We found a correlation between lower levels of vitamin D and metabolic syndrome and insulin resistance. Further studies could confirm whether restoring vitamin D levels helps reduce these cardiovascular risk factors and improve quality of life for lupus patients.”
Lupus is a rare, incurable autoimmune disease characterized by an overactive immune response and inflammation throughout the body. Left untreated, it can cause irreversible damage to major organs such as the kidneys, heart, lungs, and brain.
Metabolic syndrome, a combination of diabetes, hypertension, abnormal cholesterol levels, and obesity, puts individuals at greater risk of developing coronary heart disease, stroke, and other vascular conditions. Lupus patients already face an excess cardiovascular risk, up to 50 times higher than those without the condition, which cannot be solely attributed to traditional risk factors like high blood pressure or smoking.
Understanding the Impact of Vitamin D Deficiency on the Immune System:
Back in the 1980s, scientists noticed something interesting: our immune cells, like T and B lymphocytes, and dendritic cells, have receptors for vitamin D. This discovery got them curious about whether vitamin D plays a role in how our immune system works. These immune cells can actually produce the active form of vitamin D, called 1,25(OH)2D, right where they are needed.
When vitamin D becomes active in our immune system, it does some important things. It helps to balance our immune response by reducing certain types of T cells and their signals while increasing others that help keep our immune system in check. It also stops certain immune cells from getting too active and causing problems. This overall helps our body fight off infections better while keeping our immune system from attacking our own cells.
Even before we’re born, vitamin D can have an impact. Studies have found that babies born with low vitamin D levels may have differences in their immune system right from the start, making them more prone to inflammation.
When it comes to lupus, a condition where the immune system attacks healthy tissues, vitamin D seems to play a role too. Research shows that people with lupus tend to have lower vitamin D levels when their disease is more active. So, making sure vitamin D levels are good might not only help with lupus symptoms like fatigue and thinking problems but also with keeping the disease in check.
While the exact mechanisms linking vitamin D deficiency to high blood pressure in SLE remain unclear, researchers speculate it may involve the impact of vitamin D deficiency on the renin-angiotensin hormone system, which regulates blood pressure and systemic vascular resistance.
Dr. Reynolds emphasized the significance of the study, stating, “This is the largest-ever study examining associations between vitamin D levels and metabolic syndrome in SLE. It also benefits from being an international cohort with diverse racial and ethnic backgrounds, providing results applicable across various settings.”
