First author [ref.] | Study design | Subjects n | Type of HRT | Duration of HRT | Significant impact on number of SDB events |
Block [149] | Randomised, double-blind, placebo-controlled, parallel | 11 on treatment, 10 on placebo | Progestin | 10 weeks | No (only six out of 11 had SDB at baseline) Decrease in maximum duration of apnoea |
Pickett [150] | Randomised, single-blind, placebo-controlled, crossover | 9 | Progestin+oestrogen | 1 week | Yes |
Cistulli [151] | Open-label, two arms | 6 on oestrogen | Oestrogen | 50 days | No (significant but clinically irrelevant decrease of AHI during REM) |
9 on progestin+estrogen | Progestin+oestrogen | HVR increase, HCVR unchanged | |||
Collop [152] | Randomised, double-blinded, placebo-controlled, crossover | 8 | Progestin | 1 week | Yes Oxygen saturation increase |
Keefe [153] | Open label | 5 | Oestrogen | 3–4 weeks | Yes |
Followed by progestin+oestrogen | 12 days | 25% reduction in oestrogen group; 50% in combined therapy group | |||
Manber [154] | Open label | 6 | Oestrogen + placebo during 6–13 days | 6–13 days | Yes |
Followed by progestin+oestrogen during 6–13 days | 6–13 days | Oestrogen: reduced AHI (effect size 0.5) Attenuation of the effect by additional use progestin | |||
Wesström [155] | Open label | 5 | Progestin+oestrogen | 5–6 weeks | Yes (75% reduction in AHI) |
Saaresranta [156] | Open label | 10 | Progestin | 14 days | Static charge sensitive bed: AHI unchanged (low value at baseline) IRR pattern unchanged Decrease in mean PET,CO2over the night |
Polo-Kantola [157] | Randomised, double-blind, placebo-controlled, crossover | 62 | Oestrogen | 3 months | Static charge-sensitive bed: Yes IRR pattern unchanged |
Saaresranta [158] | Open label | 8 | Progestin | 14 days | Inspiratory flow; shapes less flow-limited |
SDB: sleep-disordered breathing; AHI: apnoea/hypopnoea index; REM: rapid eye movement; HVR: hypoxic ventilatory response; HCVR: hypercapnic ventilatory response; IRR: increased respiratory resistance pattern; PET,CO2: end-tidal carbon dioxide pressure.