[Urinary calcium excretion. (Normal values for urinary calcium/creatinine ratio in Hungary). Multicenter study]

Area of Science:

• Endocrinology and Metabolism
• Biochemistry
• Public Health

Background:

• Metabolic bone disorders pose a significant public health challenge in Hungary.
• Urinary calcium excretion is a primary biochemical indicator for assessing bone metabolism.
• Fasting urinary calcium corrected for creatinine is a globally recognized measurement.

Purpose of the Study:

• To establish standardized measurement methods for the calcium/creatinine ratio in Hungary.
• To determine reference normal values for the calcium/creatinine ratio in a healthy Hungarian population.
• To provide clinically relevant data for the biochemical assessment of bone metabolism.

Main Methods:

• Collaboration with 24 specialized centers for metabolic bone diseases.
• Standardization of urine analysis methods for calcium and creatinine.
• Determination of normal calcium/creatinine ratio values in 1846 healthy individuals (944 females, 902 males) aged 20-80 years.

Main Results:

• Established normal calcium/creatinine ratios: 0.438 ± 0.391 for females and 0.395 ± 0.352 for males (SI units).
• Observed a significant increase in the ratio with age in both sexes, peaking between 60-74 years.
• Found significantly different ratios before and after age 45 in both women and men, highlighting age-related changes.

Conclusions:

• The study successfully standardized methods and defined normal calcium/creatinine ratio values for the Hungarian population.
• Age-specific reference ranges, particularly the distinction around age 45, are recommended for clinical practice.
• These findings contribute to improved diagnosis and management of metabolic bone disorders through accurate biochemical assessment.