Vitamin D deficiency in minority populations

Abstract

Objective: Black and Hispanic individuals synthesize less vitamin D per unit of sun exposure than white individuals. The relationship between UV radiation and vitamin D insufficiency in minorities has not been well explored. Design: Prospective cohort study. Setting: Using the National Health and Nutrition Examination Survey, we obtained serum vitamin D levels for non-Hispanic Whites, Hispanics and non-Hispanic Blacks aged ≥18 years from [2000][2001][2002][2003][2004][2005][2006]. We linked these data with the average monthly solar UV index by census tract and data on sun exposure, vitamin D supplementation, health and demographics. We used multivariable regression analyses to assess vitamin D deficiency (<15 ng/ml) and insufficiency (<20 ng/ml) in January (when the UV index was lowest) by race/ethnicity and geography. Subjects: Adults (n 14 319) aged ≥18 years. Results: A 1-point increase in the UV index was associated with a 0·51 ng/ml increase in vitamin D (95 % CI 0·35, 0·67 ng/ml; P < 0·001). Non-Hispanic Black race and Hispanic ethnicity were associated with a 7·47 and 3·41 ng/ml decrease in vitamin D, respectively (both P < 0·001). In January, an estimated 65·4 % of nonHispanic Blacks were deficient in vitamin D, compared with 28·9 % of Hispanics and 14·0 % of non-Hispanic Whites. An estimated 84·2 % of non-Hispanic Blacks were insufficient in vitamin D v. 56·3 % of Hispanics and 34·8 % of non-Hispanic Whites. More non-Hispanic Blacks were estimated to be deficient in vitamin D in January in the highest UV index quartile than were non-Hispanic Whites in the lowest UV index quartile (60·2 % v. 25·7 %). Conclusions: Wintertime vitamin D insufficiency is pervasive among minority populations, and not uncommon among non-Hispanic Whites. KeywordsVitamins Vitamin D Disparities Race SurvivalThe Institute of Medicine estimates that 54 % of non-Hispanic Blacks have very low levels of vitamin D (25-hydroxycholecalifierol (25(OH)D 3 ) < 16 ng/ml), v. 27 % of Mexican Americans and 11 % of non-Hispanic Whites (1,2) . A growing literature (1)(2)(3) suggests that vitamin D may be associated with reduced mortality (overall (4) and hospital-associated (5) ), incidence of cancer (6)(7)(8)(9)(10)(11)(12)(13) , CVD (14,15) , diabetes (16) , fractures (17,18) and ageing-related functional limitations (19) , although some studies find an unclear relationship (20,21) or a harmful association with disease (22) . Randomized controlled trials are underway to examine the potential role of vitamin D in the prevention of multiple diseases, including cancer, CVD and diabetes (20,23) .There are known racial and seasonal variations in vitamin D. Black individuals synthesize less vitamin D per unit of sun exposure than white individuals, because darker complexion acts as a natural sunscreen (24,25) .The majority of vitamin D is estimated to derive from sunshine for most people (26) , with the liver converting cholecalciferol into 25(OH)D 3 , the form of vitamin D typically measured in blood serum. 25(OH)D 3 has a reported half-lif...

Vitamin D and Osteoporosis in HIV/HCV Coinfected Patients: A Literature Review

“…The analysis of patient setting showed that most of the study populations included HIV/HCV coinfected African Americans. How race affects the impact of vitamin D on bone health has recently been investigated in African American men and women, revealing differences due to socioeconomic and genetic factors, such as resistance to the bone resorbing effects of PTH in the black population [ 33 , 40 – 42 ].…”

“…However, the selected articles reveal some aspects that prompt us to reconsider the definition of hypovitaminosis D. In fact, the significance of vitamin D deficiency has several limitations because 25-hydroxyvitamin D concentrations varied by age, season, study sample size, and methodological assay approach [25(OH)D assay used] [ 37 , 39 , 40 ]. Moreover, black and Hispanic individuals synthesize less vitamin D per unit of sun exposure than white individuals [ 33 , 41 , 42 ]. Therefore, levels of vitamin D in HIV/HCV coinfected patients should be monitored according to the reference range for the sample setting.…”

Vitamin D Deficiency is Associated with Increased COVID-19 Severity: Prospective Screening of At-Risk Groups is Medically Indicated

“…Our recommendation is to expeditiously screen groups known to have both disproportionately high rates of severe COVID-19 relative to their population percentages and vitamin D de ciency. Up to 40% of African Americans are suspected to be vitamin D de cient at random seasonal testing [10] but this percentage that may reach 65 % in winter months [27]. Native Americans have been infrequently evaluated for their 25VD status but a report from Oklahoma found that two-thirds of apparently healthy individuals had 25VD below 20 ng/dL [9].…”

Risk Factors for Development of Hypocalcemia in Patients With Cancer Treated With Bone-Modifying Agents

“…For example, multiple myeloma affects black patients more than those of other racial or ethnic groups, and black patients have been shown to have a higher rate of vitamin D deficiency. 29,30 Our cohort consisted of a diverse inner-city population with cancer in a safety-net hospital setting with more racial diversity than in most prior reports on this subject. 14,15 In addition, chronic renal insufficiency is also a risk factor for hypocalcemia, even without the administration of a BMA, and it is more common in multiple myeloma.…”