Hypovitaminosis D and Its Associated Factors in North Algerian Postmenopausal Women: Results of a Cross-Sectional Study

The risk of metabolic syndrome is associated with vitamin D and inflammatory status in premenopausal and postmenopausal Algerian women

BACKGROUND

This first cross-sectional study examined whether vitamin D status and proinflammatory cytokines may be associated with metabolic syndrome (MetS) in Algerian women regarding their menopausal status.

METHODS

Fasting plasma glucose (FPG), lipids, insulin, 25(OH)D, PTH, adiponectin, resistin, TNFα, and IL-6 levels were assessed in 277 participants aged 18-74 years. MetS was diagnosed according to NCEP-ATPIII criteria. The association of vitamin D deficiency, IL-6, and TNFα with components of MetS was analyzed by the logistic regression.

RESULTS

Among a cohort of 277 participants, the prevalence of MetS in 115 premenopausal vs. 162 postmenopausal women was 54.02 vs. 68.1%. Cut-offs for vitamin D deficiency were 15.7 vs. 13 ng/mL, 51.07 vs. 41 pg/mL for IL-6 and 8.28 vs. 9.33 pg/mL for TNFα, respectively. 25(OH)D levels were positively correlated with adiponectin levels, while negatively with HOMA-IR in postmenopausal-MS + women. Adjustment for age and BMI reveals a significant association between vitamin deficiency and high FPG (OR: 2.92 vs. 2.90), TG (OR:2.79 vs. 3.51), BP (OR:2.20 vs. 1.92), and low HDL-c (OR:2.26 vs. 3.42), respectively. A significant association was also detected in postmenopausal women between IL-6 and high FPG (OR5.11, p = 0.03), BP (OR:3.13, p = 0.04), and low HDL-c (OR5.01, p = 0.02), while TNFα was associated with high BP in postmenopausal women (OR: 3.70, p = 0.01), and inversely with TG in premenopausal women (OR: 0.16, p = 0.04).

CONCLUSION

This study highlighted that severe vitamin D deficiency increases MetS score and was closely associated with four components of MetS, more potently in postmenopausal women, probably related with estrogens. Abdominal obesity, as influential component of MetS, may be involved in enhancing vitamin D deficiency, and dysregulating some metabolic hormones such as adiponectin, resistin and insulin, that contributes in onset an inflammatory state, through the increase in IL-6 and TNFα levels. These findings need to be improved by expanding investigation to a large cohort of participants.

Vitamin D status and its relationship with obesity indicators in Moroccan adult women

Background: Although vitamin D deficiency has been studied in various populations, there are few data on its prevalence and associated factors among Moroccan women. Aim: To determine the prevalence of vitamin D deficiency and investigate its association with body mass index (BMI), waist circumference, and serum concentrations of parathyroid hormone, calcium, and phosphorus in a sample of Moroccan adult women. Methods: This is a cross-sectional study conducted at Mohammed V Military Hospital of Instruction, Rabat. Anthropometric measurements and biochemical analyses were performed using standard procedures Results: A total of 714 women aged 18-65 years participated in this study. The overall prevalence of vitamin D deficiency was 74.4%. Approximately 24% and 51% of women had severe and moderate vitamin D deficiency, respectively. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were inversely correlated with BMI in vitamin D-deficient subjects (P = 0.036) and with parathyroid hormone 1-84 (PTH1-84) levels in the study sample (P = 0.010). PTH1-84 concentrations were greater among overweight/obese individuals compared to their non-overweight peers (P = 0.001) and tended to be higher among vitamin D-deficient women than vitamin D-sufficient women (P = 0.053). Conclusion: This study showed a very high prevalence of vitamin D deficiency in this sample of Moroccan women. Lower serum 25(OH)D levels were associated with increased BMI in vitamin D-deficient women and with elevated PTH1-84 levels among the study sample. Although these findings come from a convenience sample of women that attended a nutrition clinic, they underscore the urgent need to develop public health interventions to improve women's vitamin D status.

Role of food fortification with vitamin D and calcium in the bone remodeling process in postmenopausal women: a systematic review of randomized controlled trials

CONTEXT

Foods containing vitamin D reduce the deficiency of this vitamin and improve bone turnover.

OBJECTIVE

To discuss effects of the intake of vitamin D-fortified foods in isolated form or associated with calcium on bone remodeling in postmenopausal women.

DATA SOURCES

PubMed, Lilacs, Scopus, and Bireme databases. OpenThesis and Google Scholar were searched as "grey literature". Medical subject headings or similar terms related to food fortified with vitamin D and bone in postmenopausal women were used.

DATA EXTRACTION

Information was collected on study methodology and characteristics of studied populations; dosage; the food matrix used as the fortification vehicle; duration of intervention; dietary intake; 25-hydroxyvitamin D [25(OH)D] levels; serum parathyroid hormone (PTH) concentrations; bone resorption and/or formation markers (ie, carboxy terminal cross-linked telopeptide of type I collagen [CTX], tartrate-resistant acid phosphatase isoform 5b [TRAP5b], and procollagen type 1 N-terminal propeptide [P1NP]); main results; and study limitations.

DATA ANALYSIS

Five randomized controlled trials involving postmenopausal women were included. The mean ages of participants ranged from 56.1 to 86.9 years. Daily consumption of soft plain cheese fortified with 2.5 µg of vitamin D3 and 302 mg of calcium for 4 weeks resulted in a mean increase of 0.8 ng/mL in 25(OH)D and 15.9 ng/mL in P1NP levels compared with baseline, and decreased CTX, TRAP5b, and PTH values. A similar intervention for 6 weeks, using fortified cheese, showed a reduction only in TRAP5b values (-0.64 U/L). Yogurt fortified with 10 µg of vitamin D3 and 800 mg of calcium did not change P1NP values after 8 weeks of intervention, but was associated with decreases of 0.0286 ng/mL and 1.06 U/L in PTH and TRAP5b, respectively. After 12 weeks of eating the fortified yogurt, 25(OH)D levels increased by a mean of 8.8 ng/mL and PTH levels decreased in by a mean of 0.0167 ng/mL.

CONCLUSIONS

The interventions contributed toward the improvement of the bone resorption process but not to the bone formation process in postmenopausal women.

PROSPERO REGISTRATION NUMBER

CRD42019131976.

Association of vitamin D deficiency and insulin resistance with breast cancer in premenopausal Algerian women: A cross-sectional study

BACKGROUND

Low 25(OH)D levels are mainly related to breast cancer (BC) risk in postmenopausal women, while the impact of insulin resistance (IR) on BC prognosis is controversial.

OBJECTIVE

Considering the high prevalence of BC in younger Algerian women, this cross-sectional study analyzed whether vitamin D status and IR are biomarkers for breast tumor status in premenopausal women.

METHODS

In 96 women (mean age, 40.96±0.65years) newly diagnosed with BC, tumor status was determined immunohistochemically, classified by molecular subtype, then correlated with body-mass index, total plasma 25(OH)D, insulin and glucose levels and HOMA-IR, using chi², Student t, Spearman and ANOVA tests and multivariate logistic regression.

RESULTS

66 of the 98 patients (68.75%) showed vitamin D deficiency (9.74ng/mL). Overweight and obese patients with HOMA-IR >2.5, positive for HER2 and with high Ki-67 index had the most severe vitamin D deficiency. There was a significant association between vitamin D deficiency, high Ki-67 index (OR, 14.55; 95% CI, 3.43-82.59; p=0.00078) and IR (OR, 4.99; 95% CI, 1.27-24.47; p=0.03), and between IR and HER2-positivity (OR, 3.23; 95% CI, 1.05-10.56; p=0.04).

CONCLUSIONS

Vitamin D deficiency and IR are potential biomarkers for poorer prognosis in BC patients, independently of and/or synergically with high Ki-67 index and HER2-positivity in premenopausal overweight or obese women. The potential relationship of vitamin D receptor gene expression with breast cancer survival in Algerian patients will be investigated in a large cohort.

Vitamin D and health in the Mediterranean countries

Vitamin D, traditionally well known for its role in maintaining optimal health through its contribution to calcium metabolism and skeletal health, has received increased attention over the past two decades, with considerable focus being placed on its nonskeletal benefits. This paper is a narrative review of the nonskeletal health benefits of vitamin D, of particular interest to inhabitants of Mediterranean countries, namely, autism, cancer, cardiovascular disease, chronic obstructive pulmonary disease, dental caries, diabetes mellitus, erectile dysfunction, hypertension, metabolic syndrome, respiratory tract infections, all-cause mortality, and pregnancy and birth outcomes, because of the relatively high incidence and/or prevalence of these disorders in this region. Currently, the best evidence is coming out of observational studies related to serum 25-hydroxyvitamin D [25(OH)D] concentrations. Vitamin D clinical trials have generally been poorly designed and conducted, usually being based on vitamin D dose rather than 25(OH)D concentration. The optimal 25(OH)D concentration is above 75 nmol/l (30 ng/ml), with even better health outcomes in the range of 100-150 nmol/l. Achieving these concentrations with vitamin D₃ supplements will require 1000-4000 IU/day of vitamin D₃. Sensible sun exposure should also be encouraged. Countries should also consider fortifying grain and dairy products with vitamin D₃.