646 GUIDELINES MAY IMPROVE CLINICAL PRACTICE FOR DIAGNOSIS OF PRIMARY ALDOSTERONISM IN JAPAN

Abstract

Aim: The Research Group on Intractable Diseases supported by the Japanese Ministry investigated the actual conditions of clinical management of primary aldosteronism (PA), diagnosed for 5 years since January 2003 until December 2007. We performed a questionnaire survey, asking the hospitals with more than 200 beds during one year in 2010. We collected the questionnaires, concerning the clinical characteristics of 1014 patients diagnosed as PA from all areas in Japan. We analyzed the clinical data of those patients, such as unilateral or bilateral adrenal disorders, cardiovascular complications, and treatment. Results: Unilateral adrenal lesion was observed in 77% cases among all cases, and hypokalemia (K < 3.5 mEq/L) existed in 69%. The cases with ARR > 20 were observed in 83%. Furosemide + upright test, and rapid ACTH test were the most reliable examination among various confirmatory tests because 90% of the cases showed positive reaction in those two tests. Adrenal vein sampling was performed only in 66%. Cardiovascular complications and CKD were observed in 10 % when diagnosed as PA. Surgical treatment was done in 66%, and hypertension was cured in 75% of them. Discussion: Estimated numbers of PA-patients are 7487 cases during past 5 years, which are statistically calculated from the actual data. More than 40 million patients with hypertension in Japan exist, while only 1500 cases of PA were diagnosed a year. The Japan Endocrine Society had recently established the PA Guidelines (PA-GLs), saying that the prevalence of PA is found in 3.3–10% of hypertensive patients (Endocrine Journal 2011, 58 (9), 711–721). Thus, the actual numbers of PA collected from the questionnaires looks too small. It is speculated that Japanese physicians did not always screen PA because the Japanese PA-GLs were just now established after this survey. Furthermore, the PA-GLs recommend measurement of PRA and PAC in all hypertensive patients for general practitioners. The present survey suggests that only few hypertensives were screened, while the PA-GLs may enlighten all physicians to consider the possibility of PA when taking care of hypertensives in Japan.