Low vitamin D levels in people with lupus is linked to heart disease and metabolic syndrome. Boosting vitamin D may improve long-term health in lupus patients.
Systemic lupus erythematosus (SLE), is the most common type of lupus, a chronic, autoimmune disease. The immune system of a person with lupus mistakenly attacks different parts of the body, as if healthy tissues are infectious agents like bacteria or viruses. Although SLE can affect anyone, it’s most likely to occur in women.
While there are medications to help relieve symptoms, there is no cure. Researchers, however, are looking for ways lupus patients can avoid some of the most serious problems associated with the disease. And, it turns out, vitamin D may be able to lower the risk of heart problems in SLE patients.
There are three ways to get adequate amounts of the vitamin D. It is found in many foods, including egg yolks, salmon, and beef liver. Vitamin D supplements are also available. Sunshine provides the body with vitamin D, too.
When your skin is exposed to sunlight, vitamin D receptor cells on your skin convert cholesterol into vitamin D, according to Yale Medicine dermatology specialists. Lupus patients, however, are told to avoid the sun — or take extra precautions with clothing, hats, and strong sun block — because sun hypersensitivity is very common in people with SLE.
While sun avoidance helps prevent lupus skin-related flares, research suggests it may be one cause of low levels of vitamin D. And, in SLE patients, vitamin D deficiency appears to raise the risk of heart disease, metabolic syndrome, and insulin resistance that causes blood sugar to rise, according to lupus experts at the UK’s University of Birmingham and the University of Manchester.
But there’s good news. Their research suggests boosting vitamin D in lupus patients who have low levels of the vitamin may reduce heart and metabolic risks and help their overall long-term health, too.
Lupus-linked heart problems and the vitamin D link
The Centers for Disease Control and Prevention points out that people with SLE can have many different symptoms, including extreme fatigue, muscle and joint pain, skin rashes, fever, hair loss, mouth sores, anemia, abnormal blood clotting, and heart problems. Because SLE can cause inflammation anywhere in the body, if untreated the condition raises the risk of damage to major organs.
The University of Birmingham and the University of Manchester lupus research team noted SLE patients have an unusually high risk for cardiovascular disease, as much as 50 times higher than people without lupus. But that huge risk factor can’t be explained alone by well-known factors, like high blood pressure and smoking, which increase the odds for heart disease.
The researchers think, however, they may have found out why SLE increases heart disease risk. In a study of almost in 1,200 SLE patients in 11 countries (UK, USA, Canada, Spain, The Netherlands, Sweden, Iceland, Switzerland, Turkey, South Korea, and Mexico), the UK investigators found that people with lupus are more likely to have metabolic syndrome, a cluster of factors including high blood pressure, high fasting blood sugar, and low HDL (known as the “good” cholesterol). These patients are also likely to have insulin resistance if they have lower than normal vitamin D levels. And metabolic syndrome and insulin resistance substantially raise the risk of cardiovascular disease.
Vitamin D may help lupus patients in many ways
The University of Birmingham and the University of Manchester study, published in Rheumatology, noted avoiding the sun and using strong sunblock contributes to lower vitamin D levels in many people with lupus. What’s more, the research team found lupus patients with more severe disease had the most markedly low vitamin D levels.
“We found a link between lower levels of vitamin D and metabolic syndrome and insulin resistance,” explained John A Reynolds, PhD, clinical senior lecturer in Rheumatology at the University of Birmingham and co-author of the report. “This is the largest-ever study examining associations between vitamin D levels and metabolic syndrome in SLE; it also has the advantage of being an international cohort with diverse racial and ethnic backgrounds — generating results that will be applicable across many settings,”
What the exact connection is between low vitamin D, metabolic syndrome, insulin resistance, and heightened cardiovascular risks isn’t clear. The research team, however, suggests the association may be due to a negative impact of vitamin D deficiency on the renin-angiotensin hormone system, which regulates blood pressure, fluid, and electrolyte balance.
"Our results suggest that co-existing physiological abnormalities may contribute to long-term cardiovascular risk early on in SLE.,” Reynolds added. “Further studies could confirm whether restoring vitamin D levels helps to reduce these cardiovascular risk factors and improve quality of life for patients with lupus."
Bottom line: While more research is needed, raising vitamin D levels may improve control of metabolic syndrome and insulin resistance, which could lower the risk for cardiovascular problems in people with lupus. What’s more, boosting vitamin D may improve long-term outcomes for patients with SLE.
November 30, 2021
Janet O'Dell, RN