A ccumulating research suggests that l o w 2 5 -h y d r o x y v i t a m i n D 3 [25(OH)D] concentrations may be inversely associated with type 2 diabetes (1-3), metabolic syndrome (4,5), insulin resistance (6), and cardiovascular disease (CVD) (7).Much remains to be learned, however, about the relationships between vitamin D status, metabolic syndrome, and CVD. Furthermore, the published data in humans arguing that hypovitaminosis D is a CVD risk factor remain conflicting (8,9).Because this topic has received scant attention and the available information on associations between vitamin D status and CVD among type 2 diabetic adults was lacking, we examined the relationships between serum 25(OH)D concentrations and prevalent CVD in type 2 diabetic adults.RESEARCH DESIGN AND METHODS -We studied 459 consecutive type 2 diabetic outpatients attending our clinic after exclusion of those with recent acute illness or advanced chronic liver or renal disease and those who were taking medications known to alter vitamin D metabolism. The control group consisted of 459 (64% men, age 61 Ϯ 6 years) age-and sex-matched nondiabetic volunteers.Biochemical blood measurements were determined by standard laboratory procedures. Serum 25(OH)D concentrations were measured during winter months using an automated chemiluminescence immunoassay (DiaSorin Liaison). Metabolic syndrome was defined according to the Adult Treatment Panel III criteria (10). Presence of coronary (myocardial infarction, angina, or revascularization procedures), cerebrovascular (ischemic stroke, recurrent transient ischemic attacks, or carotid endarterectomy), and peripheral (claudication, lowerextremity amputation, or revascularization procedures) vascular disease was confirmed by chart review, medical history and examination, and vascular laboratory studies.Data are means Ϯ SD or frequencies. Skewed variables were logarithmically transformed to improve normality before analysis. Statistical analyses included unpaired t test, 2 test, and logistic regression analysis. In this latter analysis, CVD was considered as an aggregate end point inclusive of patients with at least one atherosclerotic manifestation. In fully adjusted logistic regression models, sex, age, BMI, smoking, diabetes duration, HbA 1c (A1C), LDL cholesterol, calcium, creatinine, albumin excretion rate, use of medications, metabolic syndrome, and inflammatory markers (fibrinogen or Creactive protein [CRP]) were also included as covariates. Hypovitaminosis D was defined as a serum 25(OH)D concentration Ͻ20 ng/ml (6,11,12).RESULTS -The mean (ϮSD) 25 (OH) D concentration was 24.1 Ϯ 9.1 ng/ml (median 22.3, range 4.9 -91.0) among control subjects and 19.7 Ϯ 10 ng/ml (17, 3-76) among diabetic patients. The ageand sex-adjusted prevalence of hypovitaminosis D was higher in diabetic patients than in control subjects (60.8 vs. 42.8%, P Ͻ 0.001).As shown in Table 1, diabetic patients with hypovitaminosis D were more likely to be women and had increased prevalence of higher values of A1C, triglycerides, CRP, and ...

We read with interest the recent review article by Mosekilde clearly documenting that vitamin D insufficiency/deficiency is a very common condition among individuals in southern European countries, especially among geriatric patients and those with hip fractures. 1 Because the available data on large population samples in Italy are limited, we would like to offer recent findings from our observational study, in which serum 25-hydroxyvitamin D3 concentrations [25(OH)D] were measured using an automated chemiluminescence immunoassay (DiaSorin LIAISON, Stillwater, MN, USA; withinand between-assay precision below 9% and 13%; analytical and functional sensitivity of 12·5 and 17·5 nmol/l, respectively) in a large sample of individuals with a wide range of age (6 months − 103 years).We studied 6403 (male/female = 1299/5104) medical inpatients and outpatients who consecutively attended the laboratory of the Hospital of Vicenza (a town in Northern Italy) for 25(OH)D measurements during the last 3 years.The mean ( ± SD) serum 25(OH)D concentration for the whole population was 45·0 ± 42 nmol/l (median 36; range 12·5-862). As shown in Table 1, there was a strong, inverse, association between serum 25(OH)D levels and age both in men and women. No significant seasonal differences in serum 25(OH)D measurements were found. Among these subjects, 52·5% ( n = 3359) had a serum 25(OH)D concentration ≤ 37·5 nmol/l with percentages steadily increasing with advancing age and ranging from 26·9% to 72·9% in men and from 39·1% to 74·8% in women. Approximately 20% ( n = 1299) of subjects had a very low 25(OH)D concentration ( ≤ 12·5 nmol/l) with percentages ranging from 11·1% to 40·2% in men and from 12·5% to 43·1% in women.Because this is not a population-based study, we stress that our results do not apply to non-institutionalized people, among whom vitamin D deficiency may be (much) lower.In conclusion, we found a high prevalence of vitamin D deficiency among unselected medical inpatients and outpatients, with a wide range of age, living in Northern Italy. Because of the potential adverse effects of vitamin D deficiency on the skeleton and other organ systems, widespread screening for vitamin D deficiency or routine vitamin D supplementation should be seriously considered.

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