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Urine Concentration Does Not Affect Biochemical Testing for Non-adherence
A D Burns1, R Alghamadi1,2, A Iqbal1,3
1Department of Metabolic Medicine and Chemical Pathology, University Hospitals of Leicester NHS Trust, Leicester Royal Infirmary, Infirmary Square, Leicester LE1 5WW, UK.
Journal of Analytical Toxicology
|December 10, 2020
Summary
Urine concentration, measured by creatinine, does not impact the accuracy of detecting antihypertensive medications using liquid chromatography-tandem mass spectrometry (LC-MS-MS). This finding validates LC-MS-MS as a reliable method for assessing medication adherence in hypertension management.
Area of Science:
- Pharmacology
- Clinical Chemistry
- Analytical Chemistry
Background:
- Hypertension is a major modifiable risk factor for cardiovascular disease.
- Medication non-adherence in hypertensive patients increases morbidity and mortality.
- Liquid chromatography-tandem mass spectrometry (LC-MS-MS) is the gold standard for objectively detecting medication non-adherence.
Purpose of the Study:
- To investigate the effect of urine concentration on the detection of antihypertensive medications using LC-MS-MS.
- To determine if urine creatinine levels influence the accuracy of adherence screening.
Main Methods:
- Biochemical adherence data for 22 antihypertensive medications from 463 subjects were analyzed.
- Urine creatinine concentration was used as a marker for urine dilution.
- Adherence scores were correlated with urine creatinine levels for each medication.
Main Results:
- Non-adherence was observed in 47.1% of samples.
- No significant differences in urine creatinine concentrations were found between detected and non-detected drug groups.
- Adherence scores remained consistent across varying urine creatinine concentrations.
Conclusions:
- Urine creatinine concentration does not affect the detection of antihypertensive medications by LC-MS-MS.
- LC-MS-MS is a robust and reliable method for assessing medication adherence, irrespective of urine dilution.
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