Disease-specific definitions of vitamin D deficiency need to be established in autoimmune and non-autoimmune chronic diseases: a retrospective comparison of three chronic diseases.
Study Goal
The researchers aimed to determine factors associated with vitamin D deficiency in patients with SLE, RA, and T2DM, including the role of serum calcium levels.
Results Summary
Higher serum calcium was associated with lower odds of vitamin D deficiency across all racial/ethnic groups studied. The effect was consistent but not the primary focus of the study.
Population
Patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and type 2 diabetes (T2DM), including African-American, Hispanic, and Other racial/ethnic groups.
Effective Dosage
Not specified
Duration
Not specified
Interactions
Bisphosphonate therapy and vitamin D supplementation were noted as factors influencing vitamin D deficiency.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
- | neutral | vitamin D deficiency | patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and type 2 diabetes (T2DM) | - | compared the odds of | #1 |
- | neutral | vitamin D deficiency | African-Americans with SLE | 59% | frequency of | #2 |
- | neutral | vitamin D deficiency | African-Americans with RA | 47% | frequency of | #3 |
- | neutral | vitamin D deficiency | African-Americans with T2DM | 67% | frequency of | #4 |
- | neutral | vitamin D deficiency | Hispanics with SLE | 67% | frequency of | #5 |
- | neutral | vitamin D deficiency | Hispanics with RA | 50% | frequency of | #6 |
- | neutral | vitamin D deficiency | Hispanics with T2DM | 59% | frequency of | #7 |
- | no change | vitamin D deficiency | RA group compared with SLE group | 1.1, 95% CI (0.62, 2.1) | adjusted odds ratio of | #8 |
- | increase | vitamin D deficiency | T2DM group compared with SLE group | 2.0, 95% CI (1.3, 3.1) | adjusted odds ratio of | #9 |
older age | decrease | vitamin D deficiency | all three racial/ethnic groups (African-American, Hispanic, Other) | - | associated with a lower odds of | #10 |
higher serum calcium | decrease | vitamin D deficiency | all three racial/ethnic groups (African-American, Hispanic, Other) | - | associated with a lower odds of | #11 |
bisphosphonate therapy | decrease | vitamin D deficiency | all three racial/ethnic groups (African-American, Hispanic, Other) | - | associated with a lower odds of | #12 |
T2DM | increase | vitamin D deficiency | some, but not all, racial/ethnic groups | - | associated with | #13 |
serum creatinine | increase | vitamin D deficiency | some, but not all, racial/ethnic groups | - | associated with | #14 |
vitamin D supplementation | decrease | vitamin D deficiency | some, but not all, racial/ethnic groups | - | associated with | #15 |
INTRODUCTION: We compared the odds of vitamin D deficiency in three chronic diseases: systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and type 2 diabetes (T2DM), adjusting for medications, demographics, and laboratory parameters, common to all three diseases. We also designed multivariate models to determine whether different factors are associated with vitamin D deficiency in different racial/ethnic groups. METHODS: We identified all patients with non-overlapping diagnoses of SLE, RA, and T2DM, with 25-hydroxyvitamin D (25OHD) levels measured between 2000 and 2009. Vitamin D deficiency was defined as 25OHD levels <20 ng/ml, based on previously established definitions. Race/ethnicity was analyzed as African-American non-Hispanic (African-American), Hispanic non-African-American (Hispanic), and Other based on self report. RESULTS: We included 3,914 patients in the final analysis: 123 SLE, 100 RA, and 3,691 T2DM. Among African-Americans the frequency of vitamin D deficiency was 59% in SLE, 47% in RA, and 67% in T2DM. Among Hispanics the frequency of vitamin D deficiency was 67% in SLE, 50% in RA, and 59% in T2DM. Compared with the SLE group, the adjusted odds ratio of vitamin D deficiency was 1.1, 95% CI (0.62, 2.1) in the RA group, and 2.0, 95% CI (1.3, 3.1) in the T2DM group. In the multivariate analysis, older age, higher serum calcium and bisphosphonate therapy were associated with a lower odds of vitamin D deficiency in all three racial/ethnic groups: 1,330 African-American, 1,257 Hispanic, and 1,100 Other. T2DM, serum creatinine, and vitamin D supplementation were associated with vitamin D deficiency in some, but not all, racial/ethnic groups. CONCLUSIONS: Vitamin D deficiency is highly prevalent in our patients with SLE, RA, and T2DM. While the odds of vitamin D deficiency are similar in RA and SLE patients in a multivariate analysis, T2DM patients have much higher odds of being vitamin D deficient. Different demographic and laboratory factors may be associated with vitamin D deficiency within different racial/ethnic groups. Therefore, disease-specific and race/ethnicity-specific definitions of vitamin D deficiency need to be established in future studies in order to define goals of vitamin D replacement in patients with autoimmune and non-autoimmune chronic diseases.