In quest for method of insulin resistance assessment in everyday clinical practice-Insulin resistance indices.

UNLABELLED: Insulin resistance (IR) a state of decreased sensitivity of target tissues to insulin is suspected usually in obese so can be overlooked in normal weight subjects thus it is important to find optimal method of IR assessment in clinical practice. METHODS: HOMA, HOMA2, QUICKI, Matsuda index were calculated using data obtained from medical history of 130 female subjects - patients of the Department of Endocrinology and Metabolic Diseases, in whom oral glucose tolerance test (OGTT) with parallel insulin concentrations assessment was performed. RESULTS: IR correlated positively with body mass index (BMI) in the entire study group, regardless which of four analyzed IR indices was used. Insulin resistance occurred in the obese as well as in normal weight and underweight subjects. The incidences of IR in the study group varied, depending upon chosen method and adopted cut-off values. CONCLUSIONS: The need for quantitative assessment of IR in clinical practice is apparent. Proper selection of the best method of IR assessment remains a problem. HOMA appears the method of first choice for clinical use. There is an urgent need to establish universal or, at least, national standard cut-off values for IR, to introduce IR assessment in clinical practice.

Hyperprolactinemia diagnostics--dilemmas over optimal selection of prolactinemia time points.

INTRODUCTION: Laboratory discrimination of pathologic hyperprolactinemia is an important step in the diagnosis of pathology influencing overall health and fertility. A major issue is the choice of time and circumstances for obtaining a blood sample for prolactin assay that would be representative for mean daily plasma concentration of a subject. OBJECTIVES: The aim of the study was a comparison of reliability of single prolactin assessment on various time-points in a day with circadian prolactinemia profile in order to find the easiest, the least expensive, and the most reliable method of hyperprolactinemia diagnosis. MATERIALS AND METHOD: The study was a retrospective analysis of 138 women, hospitalized in the Department of Endocrinology and Metabolic Diseases, Polish Mother`s Memorial Hospital - Research Institute, Lodz, Poland, in whom the circadian profile of prolactin (including assays at 8.00 am, 11.00 am, 2.00 pm, 5.00 pm, 8.00 pm, 11.00 pm, 2.00 am, 5.00 am and repeatedly at 8.00 am) had been assessed. RESULTS: On the basis of AUC (area under the curve) of prolactin concentrations, hyperprolactinemia was diagnosed in 34 subjects (24.6 % of the entire group). The attempts to diagnose hyperprolactinemia based on a single prolactin assay failed due to a high percentage of false negative and false positive results. Only significant hyperprolactinemia with mean prolactin concentration of about 100 µg/l or more appeared easy to diagnose. Combinations of several time points also appeared not reliable enough. CONCLUSION: The nine-point daily profile of prolactinemia in any patient with clinical suspicion of hyperprolactinemia seems the best mode for estimating mean circadian prolactin concentration.