Assessment of vitamin D status and serum CrossLaps levels in adults with primary lactose malabsorption

Background/Objectives: Primary adult-type lactose malabsorption (PALM) is a widespread inherited autosomal recessive condition, which is considered to be associated with osteoporosis. This prospective study aimed at assessing the 25-hydroxy-vitamin D (25(OH)D) status and serum CrossLaps levels in individuals with PALM and normal controls. Subjects/Methods: All participants ( n =210) underwent genotyping for the LCT C/T -13910 polymorphism, 25(OH)D and CrossLaps measurements and clinical examinations. In addition, the anthropometric data (that is, height, weight and body mass index) were determined. Results: Fifty-five individuals with PALM (that is, LCT C/C -13910 homozygotes) showed lower 25(OH)D (mean: 24.95±10.04 vs 28.59±9.56 ng/ml, P =0.018) and higher CrossLaps serum levels (mean: 0.46±0.31 vs 0.43±0.49 ng/ml, P =0.251) compared with 155 normal controls (that is, LCT C/T -13910 hetero- or T/T -13910 homozygotes). Anthropometric data were similar between PALM probands and controls. Conclusions: Individuals with PALM were found to have lower 25(OH)D and higher CrossLaps serum levels compared with normal controls. In order to preserve life-long bone health, routine 25(OH)D and CrossLaps serum measurements should be performed in individuals with PALM.