The Prevalence of Vitamin D and Calcium Supplement use and Association with Serum 25-Hydroxy-vitamin D (25(OH)D) and Demographic and Socioeconomic Variables in Iranian Elderly

Sara Mansouri; Maryam Safabakhsh; Abbas Rahimi Forooshani; Sakineh Shab-Bidar

doi:10.4103/ijpvm.IJPVM_379_18

The Prevalence of Vitamin D and Calcium Supplement use and Association with Serum 25-Hydroxy-vitamin D (25(OH)D) and Demographic and Socioeconomic Variables in Iranian Elderly

Int J Prev Med. 2021 Apr 17:12:36. doi: 10.4103/ijpvm.IJPVM_379_18. eCollection 2021.

Authors

Sara Mansouri¹, Maryam Safabakhsh¹, Abbas Rahimi Forooshani², Sakineh Shab-Bidar¹

Affiliations

¹ Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
² Department of Biostatistics and Epidemiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Abstract

Aims: The objective of this study was to determine the prevalence of vitamin D and calcium supplement use, and association with serum 25-hydroxy-vitamin D(25(OH)D) and demographic and socioeconomic variables in Iranian elderly.

Settings and design: This cross-sectional study was conducted in health centers of Tehran, capital of Iran.

Methods: A total of 600 men and women were recruited using a two-stage cluster sampling method from 60 health centers. Participant's inclusion criteria included enrolling older adults over 60 years old who able to answer questions. We used valid and reliable questionnaires to record dietary intake of vitamin D and calcium. Any dietary supplements which included vitamin D/calcium were recorded. 25(OH)D level was measured. Participants were categorized as supplement users if they had taken supplements during last month.

Results: The mean age of participants was 67.16 ± 6.07 years. Vitamin D supplements were used more often by females (OR = 11.89, 95% confidence interval (CI): 4.82-29.34), high educated subjects (OR = 3.49, 95% CI: 1.45-8.44), participants who did more physical activities (OR = 2.75, 95% CI: 1.52-5.00), and subjects who took antiosteoporosis medications (OR = 6.90, 95% CI: 2.84‑16.78). Calcium supplements were used more often by females (OR = 13.05, 95% CI: 5.19-32.81), more physical activities participants (OR = 2.17, 95% CI: 1.20-3.92), and antiosteoporosis users (OR = 8.31, 95% CI: 3.43-20.14). Significant positive associations were seen between 25(OH) D levels and osteoporosis (P = 0.020), vitamin D supplement use (P < 0.0001), and sun exposure (P = 0.093).

Conclusion: In this population of Tehranian adults, the prevalence of vitamin D and calcium supplement use may be attributed to educational level and underlying disease. Vitamin D supplementation, osteoporosis, and sun exposure were the strong predictors of vitamin D status.

Keywords: Calcium supplements; Iran; elderly; serum vitamin D; vitamin D supplements.