ISSN: 2578-4641
Authors: Aljabri KS* and Bokhari SA
Introduction: The impact of seasonal changes over serum vitamin D has been addressed in several previous studies. We conducted a cross sectional study to investigate the status of vitamin D seasonal variation in an ambulatory adult population of Jeddah, one of the western most regions of the Saudi Arabia. Method: A cross-sectional single centre study was conducted in 4053 patients with type 2 diabetes mellitus (T2DM). Patients with T2DM attended the Diabetes Centre at King Fahad Armed Forces Hospital, Jeddah, Saudi Arabia between January 2018 and December 2018 were recruited. Results: A total of 9504 subjects with T2DM 27.5% females and 72.5% males) with mean age of 53.9 ±16.5 years entered into the study. The mean serum 25(OH)D levels varied across the various months from the lowest level at 46.1±26.6 nmol/l in August to the highest level at 64.9±30.3 nmol/l in January. The mean serum 25(OH)D levels varied significantly across the various seasons from the lowest level at 52.0±28.6 nmol/l in the summer to the highest level at 62.2±30.6 nmol/l in the winter (p<0.0001). Females had significantly higher serum 25-OHD concentrations than the males (59.9±31.8 and 53.1±27.4 years respectively, p<0.0001). Serum 25(OH)D levels varied significantly higher in females across the different seasons except for fall season. The subjects aged higher than 70 years had the highest serum 25(OH)D levels whereas, the subjects aged less than 30 years had the lowest values and the differences between the age groups of 70 years and below was significant. There were statistically significant wide variations in serum 25(OH)D across the various seasons in all decades of age . Conclusions: This study indicates that seasonal changes lead to significant serum vitamin D variations with the lowest values in the summer and in the fall and the highest values the winter and in the spring.
Keywords: Seasonal Variation in Vitamin D levels
