The purpose of this study is to determine the effects of vitamin D on measures of bone health and immune function in HIV infected postmenopausal women. The investigators prior research with this population revealed that low vitamin D levels are very common. Prior research with this population also revealed that Vitamin D is necessary for the body to absorb calcium and is important for the health of the bones. When vitamin D levels are low, there are increased risks of bone loss, muscle weakness, falls and fractures. Low levels of vitamin D have also been associated with impaired immune function. This study will help us learn whether two different doses of vitamin D will improve bone health and immune function.

The purpose of this study is to determine the effects of vitamin D repletion on rates of bone loss and indices of immune function in HIV+ postmenopausal women. Lower baseline serum Vitamin D levels, as assessed by measuring serum 25-hydroxyvitamin D (25-OHD) were associated with a trend toward more bone loss. In addition, the investigators found that despite providing supplements that contained approximately 600 IU vitamin D, serum 25-OHD did not increase during the first year. Provision of adequate calcium and vitamin D is the cornerstone of effective prevention and therapy of osteoporosis. HIV-infected patients may be at increased risk of having vitamin D deficiency because they take several medications that may interfere with vitamin D action. Therefore, the investigators will recruit 100 HIV infected postmenopausal women for this study who are on a stable antiretroviral therapy (ART) regimen and randomize them to receive 1000 or 3000 IU of vitamin D daily. The subjects will be followed closely for one year to monitor compliance and changes in bone health and immune function.

Inclusion Criteria:

• HIV+ African American and Latina postmenopausal women, aged 40-70, who meet the standard definition of menopause:

If 50 years old or older then amenorrhea for > 1year. If age 40 to 49 then amenorrhea for over a year and and Follicle-Stimulating Hormone (FSH) level of equal to or greater than 20 mIU/ml; as some amenorrheic chronically ill women may have hypothalamic dysfunction and low FSH values, if FSH is 10 to 19, and the serum estradiol level is consistent with menopause less than or equal to 30pg/ml, she will be determined to be postmenopausal.

• On stable antiretroviral therapy (ART) for >2 years
• Undetectable HIV RNA (viral load) at least 2 times over the past year (RNA <400)

Exclusion Criteria:

• Metabolic bone disease (Paget's disease, clinical osteomalacia, primary hyperparathyroidism, hypercalcemia)
• Multiple myeloma, solid tumors with metastases;
• Endocrinopathy (hyperthyroidism, untreated hypothyroidism, Cushing's syndrome, prolactin-secreting pituitary adenoma)
• Renal insufficiency (serum creatinine above 1.5 mg/dl)
• Liver disease (AST, ALT, bilirubin, total alkaline phosphatase activity > twice upper normal limit);
• Intestinal disorders (celiac disease, pancreatic insufficiency, Crohn's disease, ulcerative colitis)
• Current use of glucocorticoids, anticonvulsants, anticoagulants, diuretics, methotrexate;
• Current or past use of drug therapies for osteoporosis (raloxifene, bisphosphonates, calcitonin, PTH). Women on estrogen are excluded. Past estrogen use is permitted if discontinued >1 year before enrollment.
• If there is a history of a low trauma fracture, a T score < -3 or a prevalent vertebral fracture on Instant Vertebral Assessment™ (IVA), subjects will be referred for osteoporosis treatment as appropriate.
• Severe vitamin D deficiency (25-OHD level <10 ng/ml) or normal baseline serum vitamin D (25-OHD >32 ng/ml). Subjects with severe vitamin D deficiency may be referred to our sub-study, if all other inclusion/exclusion criteria are met.
• Hypercalcemia or history of calcium-containing kidney stones
• Known allergy/sensitivity or any hypersensitivity to components of study drugs or their formulations
• Current imprisonment or voluntary incarceration in a medical facility for psychiatric illness
• Any condition that, in the opinion of the site investigator, would compromised the subject's ability to participate in the study

HIV-infected postmenopausal African American or Hispanic women between ages 40-70 were recruited from 4 sites in New York City. All participants had serum 25-OHD ≥10 ng/mL and < 32 ng/mL and were on stable ART for at least 2 years with 2 or more HIV RNA levels <400 copies/ml within the last year prior to enrollment.

1 year

Adverse event reporting was collected at every visit as part of the protocol.