Medroxyprogesterone acetate and COPD. Effect on breathing and oxygenation in sleeping and awake patients

The effects of oral medroxyprogesterone acetate (MPA) (20 mg three times daily) were assessed on sleep-disordered breathing and on arterial blood gas levels in awake patients with chronic obstructive pulmonary disease (COPD). Seventeen men and two women (mean baseline PaO2, 65 mm Hg; PaCO2, 41 mm Hg; and FEV1/FVC ratio, 48 percent) participated in a double-blind, placebo-controlled, randomized study. After an initial night of polysomnography and daytime arterial blood gas analysis, the patients were randomized to receive either MPA or an identical placebo for one month; the studies were then repeated. The alternate compound was given for an additional month, and the studies were performed a third time. MPA in awake patients was associated with an increased mean PaO2 value, reduced PaCO2, and increased pH. Although there was no significant change in the number of episodes of sleep apnea, hypopnea, desaturation, or the minimal saturation, MPA marginally decreased the number of minutes of total sleep time when oxygen saturation was less than 90 percent (p = .06). In conclusion, MPA improves oxygenation and CO2 elimination and increases the pH in awake patients with COPD, but during sleep, does not significantly affect disordered breathing and only marginally improves desaturation.