Tags

Type your tag names separated by a space and hit enter

Seasonal Variability in Vitamin D Levels No Longer Detectable in Primary Hyperparathyroidism.
J Clin Endocrinol Metab 2015; 100(9):3452-9JC

Abstract

CONTEXT

Seasonal variability in 25-hydroxyvitamin D [25(OH)D] and PTH levels in the general population has been associated with differences in bone turnover markers, bone density, and fracture risk. Seasonal variability in 25(OH)D and PTH levels has also been reported in primary hyperparathyroidism (PHPT).

OBJECTIVE

Given the widespread use of vitamin D supplements, we sought to determine whether patients with PHPT still demonstrated seasonal variation in 25(OH)D levels.

DESIGN AND SETTING

This cross-sectional study was conducted at a university medical center at a Northeastern U.S. latitude (New York, NY).

PATIENTS

One hundred patients with PHPT participated in the study.

OUTCOME MEASURES

We assessed vitamin D supplement use and seasonal variation in serum 25(OH)D.

RESULTS

Patients had PHPT ([mean ± SD] calcium, 10.8 ± 1.0 mg/dL; PTH, 85 ± 48 pg/mL) with a mean 25(OH)D level of 29 ± 10 ng/mL. Although only one fifth of participants had vitamin D deficiency (19% < 20 ng/mL), more than half were either deficient or insufficient (54% < 30 ng/mL). Sun exposure varied by season, but there were no seasonal differences in levels of 25(OH)D, PTH, bone markers, or bone mineral density, or in the prevalence of 25(OH)D less than 20 or less than 30 ng/mL. Most of the participants (65%) took supplemental vitamin D (dose among users: mean, 1643 ± 1496 IU; median, 1000 IU daily), and supplement users had markedly better vitamin D status than nonusers (25(OH)D < 20 ng/mL: 8 vs 40%; P < .0001; < 30 ng/mL: 40 vs 80%; P = .0001; ≥ 30 ng/mL: 60 vs 20%; P = .0001).

CONCLUSIONS

We found no evidence of seasonal variation in 25(OH)D levels or PHPT disease severity in the Northeastern United States. This change is likely due to widespread high vitamin D supplement intake, which has resulted in better vitamin D status among supplement users and can mask the effect of season on serum 25(OH)D levels.

Authors+Show Affiliations

Department of Medicine, Columbia University, College of Physicians and Surgeons, New York City, New York 10032.Department of Medicine, Columbia University, College of Physicians and Surgeons, New York City, New York 10032.Department of Medicine, Columbia University, College of Physicians and Surgeons, New York City, New York 10032.Department of Medicine, Columbia University, College of Physicians and Surgeons, New York City, New York 10032.Department of Medicine, Columbia University, College of Physicians and Surgeons, New York City, New York 10032.Department of Medicine, Columbia University, College of Physicians and Surgeons, New York City, New York 10032.

Pub Type(s)

Journal Article
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

26120793

Citation

Cong, Elaine, et al. "Seasonal Variability in Vitamin D Levels No Longer Detectable in Primary Hyperparathyroidism." The Journal of Clinical Endocrinology and Metabolism, vol. 100, no. 9, 2015, pp. 3452-9.
Cong E, Walker MD, Kepley A, et al. Seasonal Variability in Vitamin D Levels No Longer Detectable in Primary Hyperparathyroidism. J Clin Endocrinol Metab. 2015;100(9):3452-9.
Cong, E., Walker, M. D., Kepley, A., Zhang, C., McMahon, D. J., & Silverberg, S. J. (2015). Seasonal Variability in Vitamin D Levels No Longer Detectable in Primary Hyperparathyroidism. The Journal of Clinical Endocrinology and Metabolism, 100(9), pp. 3452-9. doi:10.1210/JC.2015-2105.
Cong E, et al. Seasonal Variability in Vitamin D Levels No Longer Detectable in Primary Hyperparathyroidism. J Clin Endocrinol Metab. 2015;100(9):3452-9. PubMed PMID: 26120793.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Seasonal Variability in Vitamin D Levels No Longer Detectable in Primary Hyperparathyroidism. AU - Cong,Elaine, AU - Walker,Marcella D, AU - Kepley,Anna, AU - Zhang,Chiyuan, AU - McMahon,Donald J, AU - Silverberg,Shonni J, Y1 - 2015/06/29/ PY - 2015/6/30/entrez PY - 2015/6/30/pubmed PY - 2015/12/15/medline SP - 3452 EP - 9 JF - The Journal of clinical endocrinology and metabolism JO - J. Clin. Endocrinol. Metab. VL - 100 IS - 9 N2 - CONTEXT: Seasonal variability in 25-hydroxyvitamin D [25(OH)D] and PTH levels in the general population has been associated with differences in bone turnover markers, bone density, and fracture risk. Seasonal variability in 25(OH)D and PTH levels has also been reported in primary hyperparathyroidism (PHPT). OBJECTIVE: Given the widespread use of vitamin D supplements, we sought to determine whether patients with PHPT still demonstrated seasonal variation in 25(OH)D levels. DESIGN AND SETTING: This cross-sectional study was conducted at a university medical center at a Northeastern U.S. latitude (New York, NY). PATIENTS: One hundred patients with PHPT participated in the study. OUTCOME MEASURES: We assessed vitamin D supplement use and seasonal variation in serum 25(OH)D. RESULTS: Patients had PHPT ([mean ± SD] calcium, 10.8 ± 1.0 mg/dL; PTH, 85 ± 48 pg/mL) with a mean 25(OH)D level of 29 ± 10 ng/mL. Although only one fifth of participants had vitamin D deficiency (19% < 20 ng/mL), more than half were either deficient or insufficient (54% < 30 ng/mL). Sun exposure varied by season, but there were no seasonal differences in levels of 25(OH)D, PTH, bone markers, or bone mineral density, or in the prevalence of 25(OH)D less than 20 or less than 30 ng/mL. Most of the participants (65%) took supplemental vitamin D (dose among users: mean, 1643 ± 1496 IU; median, 1000 IU daily), and supplement users had markedly better vitamin D status than nonusers (25(OH)D < 20 ng/mL: 8 vs 40%; P < .0001; < 30 ng/mL: 40 vs 80%; P = .0001; ≥ 30 ng/mL: 60 vs 20%; P = .0001). CONCLUSIONS: We found no evidence of seasonal variation in 25(OH)D levels or PHPT disease severity in the Northeastern United States. This change is likely due to widespread high vitamin D supplement intake, which has resulted in better vitamin D status among supplement users and can mask the effect of season on serum 25(OH)D levels. SN - 1945-7197 UR - https://www.unboundmedicine.com/medline/citation/26120793/Seasonal_Variability_in_Vitamin_D_Levels_No_Longer_Detectable_in_Primary_Hyperparathyroidism_ L2 - https://academic.oup.com/jcem/article-lookup/doi/10.1210/JC.2015-2105 DB - PRIME DP - Unbound Medicine ER -