Urban tropospheric ozone increases the prevalence of vitamin D deficiency among Belgian postmenopausal women with outdoor activities during summer.

Abstract

CONTEXT:

By absorbing sunlight UVB and thereby reducing cutaneous vitamin D photosynthesis, ozone, a common urban pollutant, could cause hypovitaminosis D.

OBJECTIVES:

The objective of the study was to establish the characteristics and percentage of subjects with serum 25-hydroxyvitamin D [25(OH)D] less than 75 nmol/liter among postmenopausal women engaging in outdoor activities in either Brussels or the countryside.

DESIGN/SETTING:

This was a cross-sectional study conducted in a university research hospital.

PATIENTS/METHODS:

Among 249 women consulting for either shoulder tendonitis or lumbar spine osteoarthritis, 121 free of conditions and drugs affecting bone and calcium metabolism completed two food-frequency questionnaires within 15 d and we selected the 85 subjects with retest scores within the +/- 15% of test scores. Other parameters included sun exposure index (SEI), PTH levels, and femoral neck T-score.

RESULTS:

Urban residents (n = 38) and rural residents (n = 47) did not differ in mean ages, body mass indices, and vitamin D intakes. When compared with rural inhabitants, urban inhabitants were exposed to ozone levels 3 times higher, and despite a higher mean SEI (113 vs. 87; P < 0.001), they had a higher prevalence of 25(OH)D less than 75 nmol/liter (84 vs. 38%). After adjusting for SEI, 25(OH)D was 2-fold higher in rural residents, and after adjusting for 25(OH)D, SEI was 3-fold higher in urban residents. Femoral neck T-scores correlated positively with 25(OH)D and negatively with PTH levels.

CONCLUSIONS:

Air pollution may be a neglected risk factor for hypovitaminosis D, which is known to compromise several health outcomes. As long as 25(OH)D is greater than 75 nmol/liter, calcium intakes greater than 17.5 mmol/d are unnecessary to prevent elevations in PTH levels.

• Authors: Daniel-Henri Manicourt, Jean-Pierre Devogelaer
• Journal: The Journal of clinical endocrinology and metabolism (J Clin Endocrinol Metab) Vol. 93 Issue 10 Pg. 3893-9 (Oct 2008) ISSN: 0021-972X [Print] United States
• PMID: 18628525 (Publication Type: Journal Article)

Chemical References

• Parathyroid Hormone
• Vitamin D
• Ozone
• 25-hydroxyvitamin D

Topics

• Aged
• Aged, 80 and over
• Atmosphere
• Belgium (epidemiology)
• Bone Density (drug effects, physiology)
• Cities
• Female
• Femur Neck (diagnostic imaging)
• Humans
• Middle Aged
• Motor Activity (drug effects, physiology)
• Ozone (pharmacology)
• Parathyroid Hormone (blood)
• Postmenopause (drug effects)
• Prevalence
• Radiography
• Seasons
• Sunlight
• Vitamin D (analogs & derivatives, blood)
• Vitamin D Deficiency (blood, epidemiology)