Pioglitazone vs Placebo in Combination With Niacin Extended Release on Low HDL

Inclusion Criteria: Men and women between the ages of 18 and 75 HDL-C ≤ 40 mg/dL for Men and HDL-C < 50 mg/dl for Women* At least two of the following criteria (a, b, c, or d) listed below: Abdominal obesity (waist circumference: men 40 inches and women 35 inches)** Blood pressure > 130/>85 mmHg in untreated patients OR use of any antihypertensive agent. Fasting glucose > 100 mg/dL but < 126 mg/dL Fasting triglycerides > 150 mg/dL Exclusion Criteria: Diabetes or use of anti-hyperglycemic medication in the last 3 months (subjects with a fasting blood glucose of > 110 mg/dL will have an oral glucose tolerance test (OGTT) to rule out diabetes mellitus). Subjects on statin therapy may be enrolled, but only if they have been on a stable dose for at least 3 months, and are not expected to require titration of statin therapy during the course of the study. Uncontrolled hypertension (defined as systolic bp > 180, diastolic BP > 100). Triglycerides > 400 mg/dL LDL-cholesterol level > 190 mg/dl History of chronic renal insufficiency (serum creatinine >2.0 mg/dl). History of liver disease or abnormal liver function tests (LFTs) (>2x upper limit normal) Hemoglobin < 10 mg/dL History of congestive heart failure (NYHA Class III or IV) Women who are pregnant or lactating History of a non-skin malignancy within the previous 5 years Any major active rheumatologic, pulmonary, or dermatologic disease or other chronic inflammatory condition Surgery in the last 90 days History of HIV positive Active alcohol or drug abuse Active peptic ulcer disease Gout attack within the past 6 months Participation in an investigational drug study within 6 weeks Serious or unstable medical or psychological conditions that, in the opinion of the investigator, would compromise the subject's safety or successful study participation Subjects on warfarin may be enrolled, but they will be excluded from the optional adipose biopsy.