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Prospective associations of vitamin D with β-cell function and glycemia: the PROspective Metabolism and ISlet cell Evaluation (PROMISE) cohort study.

Kayaniyil S, Retnakaran R, Harris SB, Vieth R, Knight JA, Gerstein HC, Perkins BA, Zinman B, Hanley AJ - Diabetes (2011)

Bottom Line: Multivariate linear regression analyses indicated no significant association of baseline 25(OH)D with follow-up IS(OGTT) or HOMA-IR.There were, however, significant positive associations of baseline 25(OH)D with follow-up IGI/IR (β = 0.005, P = 0.015) and ISSI-2 (β = 0.002, P = 0.023) and a significant inverse association of baseline 25(OH)D with follow-up AUC(glucose) (β = -0.001, P = 0.007).Logistic regression analyses indicated a significant reduced risk of progression with higher baseline 25(OH)D (adjusted odds ratio 0.69 [95% CI 0.53-0.89]), but this association was not significant after additional adjustment for baseline and change in BMI (0.78 [0.59-1.02]).

View Article: PubMed Central - PubMed

Affiliation: Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada.

ABSTRACT

Objective: To examine the prospective associations of baseline vitamin D [25-hydroxyvitamin D; 25(OH)D] with insulin resistance (IR), β-cell function, and glucose homeostasis in subjects at risk for type 2 diabetes.

Research design and methods: We followed 489 subjects, aged 50 ± 10 years, for 3 years. At baseline and follow-up, 75-g oral glucose tolerance tests (OGTTs) were administered. IR was measured using the Matsuda index (IS(OGTT)) and the homeostasis model assessment of IR (HOMA-IR), β-cell function was determined using both the insulinogenic index divided by HOMA-IR (IGI/IR) and the insulin secretion sensitivity index-2 (ISSI-2), and glycemia was assessed using the area under the glucose curve (AUC(glucose)). Regression models were adjusted for age, sex, ethnicity, season, and baseline value of the outcome variable, as well as baseline and change in physical activity, vitamin D supplement use, and BMI.

Results: Multivariate linear regression analyses indicated no significant association of baseline 25(OH)D with follow-up IS(OGTT) or HOMA-IR. There were, however, significant positive associations of baseline 25(OH)D with follow-up IGI/IR (β = 0.005, P = 0.015) and ISSI-2 (β = 0.002, P = 0.023) and a significant inverse association of baseline 25(OH)D with follow-up AUC(glucose) (β = -0.001, P = 0.007). Progression to dysglycemia (impaired fasting glucose, impaired glucose tolerance, or type 2 diabetes) occurred in 116 subjects. Logistic regression analyses indicated a significant reduced risk of progression with higher baseline 25(OH)D (adjusted odds ratio 0.69 [95% CI 0.53-0.89]), but this association was not significant after additional adjustment for baseline and change in BMI (0.78 [0.59-1.02]).

Conclusions: Higher baseline 25(OH)D independently predicted better β-cell function and lower AUC(glucose) at follow-up, supporting a potential role for vitamin D in type 2 diabetes etiology.

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Related in: MedlinePlus

Baseline serum 25(OH)D by glycemic progression status at follow-up. DM, type 2 diabetes; Pre-DM refers to IFG or IGT. None of the pairwise associations were statistically significant.
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Figure 1: Baseline serum 25(OH)D by glycemic progression status at follow-up. DM, type 2 diabetes; Pre-DM refers to IFG or IGT. None of the pairwise associations were statistically significant.

Mentions: Baseline serum 25(OH)D according to glycemic progression status is described in Fig. 1. Those who remained normal glucose tolerant (n = 352) or regressed to NGT (n = 6) at follow-up had significantly higher serum 25(OH)D levels compared with those who were dysglycemic at follow-up (n = 131) (59.84 ± 23.07 nmol/L vs. 53.03 ± 23.16 nmol/L, respectively, P = 0.0041). Multivariate logistic regression analyses indicated a significant reduced risk of progression to dysglycemia per SD increase in baseline serum 25(OH)D after adjustment for age, sex, ethnicity, season, and baseline and change in both physical activity and vitamin D supplement use (Fig. 2). However, this association was attenuated with additional adjustment for baseline and change in BMI (odds ratio 0.78 [95% CI 0.59–1.02]). In addition, results were essentially the same in sensitivity analyses additionally adjusting for PTH or for family history of type 2 diabetes and baseline C-reactive protein.


Prospective associations of vitamin D with β-cell function and glycemia: the PROspective Metabolism and ISlet cell Evaluation (PROMISE) cohort study.

Kayaniyil S, Retnakaran R, Harris SB, Vieth R, Knight JA, Gerstein HC, Perkins BA, Zinman B, Hanley AJ - Diabetes (2011)

Baseline serum 25(OH)D by glycemic progression status at follow-up. DM, type 2 diabetes; Pre-DM refers to IFG or IGT. None of the pairwise associations were statistically significant.
© Copyright Policy - creative-commons
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3198096&req=5

Figure 1: Baseline serum 25(OH)D by glycemic progression status at follow-up. DM, type 2 diabetes; Pre-DM refers to IFG or IGT. None of the pairwise associations were statistically significant.
Mentions: Baseline serum 25(OH)D according to glycemic progression status is described in Fig. 1. Those who remained normal glucose tolerant (n = 352) or regressed to NGT (n = 6) at follow-up had significantly higher serum 25(OH)D levels compared with those who were dysglycemic at follow-up (n = 131) (59.84 ± 23.07 nmol/L vs. 53.03 ± 23.16 nmol/L, respectively, P = 0.0041). Multivariate logistic regression analyses indicated a significant reduced risk of progression to dysglycemia per SD increase in baseline serum 25(OH)D after adjustment for age, sex, ethnicity, season, and baseline and change in both physical activity and vitamin D supplement use (Fig. 2). However, this association was attenuated with additional adjustment for baseline and change in BMI (odds ratio 0.78 [95% CI 0.59–1.02]). In addition, results were essentially the same in sensitivity analyses additionally adjusting for PTH or for family history of type 2 diabetes and baseline C-reactive protein.

Bottom Line: Multivariate linear regression analyses indicated no significant association of baseline 25(OH)D with follow-up IS(OGTT) or HOMA-IR.There were, however, significant positive associations of baseline 25(OH)D with follow-up IGI/IR (β = 0.005, P = 0.015) and ISSI-2 (β = 0.002, P = 0.023) and a significant inverse association of baseline 25(OH)D with follow-up AUC(glucose) (β = -0.001, P = 0.007).Logistic regression analyses indicated a significant reduced risk of progression with higher baseline 25(OH)D (adjusted odds ratio 0.69 [95% CI 0.53-0.89]), but this association was not significant after additional adjustment for baseline and change in BMI (0.78 [0.59-1.02]).

View Article: PubMed Central - PubMed

Affiliation: Department of Nutritional Sciences, University of Toronto, Toronto, Ontario, Canada.

ABSTRACT

Objective: To examine the prospective associations of baseline vitamin D [25-hydroxyvitamin D; 25(OH)D] with insulin resistance (IR), β-cell function, and glucose homeostasis in subjects at risk for type 2 diabetes.

Research design and methods: We followed 489 subjects, aged 50 ± 10 years, for 3 years. At baseline and follow-up, 75-g oral glucose tolerance tests (OGTTs) were administered. IR was measured using the Matsuda index (IS(OGTT)) and the homeostasis model assessment of IR (HOMA-IR), β-cell function was determined using both the insulinogenic index divided by HOMA-IR (IGI/IR) and the insulin secretion sensitivity index-2 (ISSI-2), and glycemia was assessed using the area under the glucose curve (AUC(glucose)). Regression models were adjusted for age, sex, ethnicity, season, and baseline value of the outcome variable, as well as baseline and change in physical activity, vitamin D supplement use, and BMI.

Results: Multivariate linear regression analyses indicated no significant association of baseline 25(OH)D with follow-up IS(OGTT) or HOMA-IR. There were, however, significant positive associations of baseline 25(OH)D with follow-up IGI/IR (β = 0.005, P = 0.015) and ISSI-2 (β = 0.002, P = 0.023) and a significant inverse association of baseline 25(OH)D with follow-up AUC(glucose) (β = -0.001, P = 0.007). Progression to dysglycemia (impaired fasting glucose, impaired glucose tolerance, or type 2 diabetes) occurred in 116 subjects. Logistic regression analyses indicated a significant reduced risk of progression with higher baseline 25(OH)D (adjusted odds ratio 0.69 [95% CI 0.53-0.89]), but this association was not significant after additional adjustment for baseline and change in BMI (0.78 [0.59-1.02]).

Conclusions: Higher baseline 25(OH)D independently predicted better β-cell function and lower AUC(glucose) at follow-up, supporting a potential role for vitamin D in type 2 diabetes etiology.

Show MeSH
Related in: MedlinePlus