You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Outcome", "Participant", "Intervention"].

Please return the output as a JSON object of the format: {"Participant" : ["patients with COPD", ...], "Intervention" : ["Atenolol", ...], "Outcome" : ["blood pressure", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

[ Simvastatin versus gemfibrozil in the treatment of primary hypercholesterolemia in hypertensive patients treated with hydrochlorothiazide ] . Recent pharmacological studies confirmed the role of hypercholesterolemia in the pathogenesis of coronary atherosclerosis . A 10 % reduction in cholesterol levels can reduce the risk of coronary heart disease by 15 % . However many hypercholesterolemic patients often suffer from arterial hypertension and drugs such as thiazide diuretics cause an imbalance in lipid metabolism . The efficacy and the tolerability of simvastatin ( a inhibitor of HGM-CoA reductase ) with that of gemfibrozil ( a fibric acid derivative , which can reduce the VLDL level ) were compared in a placebo-controlled study in 2 groups of patients with primary hypercholesterolemia and mild-to-moderate essential hypertension treated with hydrochlorothiazide . After 10 weeks standard hypolipidemic diet and hydrochlorothiazide ( 25 mg od ) therapy , 30 patients whose cholesterol levels were still greater than or equal to 250 mg/100 ml and whose diastolic blood pressure was less than 95 mmHg were randomized to one of the following treatments : simvastatin , 20 mg od , gemfibrozil , 600 mg bid or placebo , while continuing dietetic and diuretic treatment . After 24 weeks treatment , simvastatin induced a 37 % reduction in cholesterol plasma levels , a 9 % increase of HDL and a 16 % reduction of LDL . APO-A1 showed a 4 % increase , while APO-B showed a 3 % reduction . Gemfibrozil induced a 20 % reduction in plasma triglycerides and a 13 % decrease in plasma cholesterol , with a significant 19 % increase in HDL and a 11 % reduction in LDL . No significant variations in any of the lipid parameters monitored were observed in the placebo group . Treatment with simvastatin or gemfibrozil in hypertensive patients in hydrochlorothiazide monotherapy can reduce total cholesterol and LDL-cholesterol plasma levels , while significantly increasing HDL plasma levels compared to placebo . Simvastatin , however , resulted more efficient than gemfibrozil on total cholesterol or cholesterol fractions .
{"Intervention": ["thiazide diuretics", "placebo", "gemfibrozil", "hydrochlorothiazide ]", "hydrochlorothiazide", "standard hypolipidemic diet", "or placebo", "[ Simvastatin versus gemfibrozil", "placebo-controlled", "Gemfibrozil", "simvastatin", "Simvastatin"], "Outcome": ["HDL", "plasma cholesterol", "efficacy and the tolerability", "cholesterol plasma levels", "diastolic blood", "LDL . APO-A1", "HDL plasma levels", "total cholesterol and LDL-cholesterol plasma levels", "cholesterol levels", "LDL .", "plasma triglycerides", "total cholesterol or cholesterol fractions ."], "Participant": ["primary hypercholesterolemia in hypertensive patients treated with hydrochlorothiazide ]", "mild-to-moderate essential hypertension", "30"]}