Parathyroid hormone, vitamin D levels and urine albumin excretion in older persons: the 2011 Korea National Health and Nutrition Examination Survey (KNHANES)

Objective: Persistent elevation of urinary albumin excretion (UAE), even within normal range, is an independent predictor for cardiovascular disease. Accumulating research suggests that low levels of vitamin D and high levels of parathyroid hormone (PTH) also increase cardiovascular disease risk. This study is intended to investigate the relationship between PTH, vitamin D levels and UAE.

Methods: We examined 2897 adults aged 50 and above, participating in the second year of the fifth Korea National Health and Nutrition Examination Survey (KNHANES V-2). Anthropometric and laboratory measurements were performed. Elevated UAE was defined as spot urinary albumin creatinine ratio equal or above 10.

Results: The proportion of elevated UAE (21·8%, 23·2%, 23·2%, 31·8%; P for trend = 0·002) rose with increasing quartiles of PTH. The odds ratio for elevated UAE in the highest quartile of PTH was 72% higher than the lowest quartile group. There was no relationship between vitamin D and elevated UAE.

Conclusions: Elevated PTH levels are associated with elevated UAE in Korean adults aged 50 and above. Additional studies are needed to clarify this relationship.