Sorokina 2019a.

Study characteristics
Methods	RCT
Participants	Number randomised/analysed: 18/18 Sex (% male): not reported (mostly men) Age: not reported (adults) Inclusion criteria CSA (AHI > 15 events/hour) CHF (NYHA functional class II or III) Exclusion criteria Chronic respiratory failure Renal failure Previous stroke Anaemia Obesity
Interventions	Intervention group: acetazolamide (carbonic anhydrase inhibitor) 250 mg plus standard medical treatment (n = 8) Control group: standard medical treatment (inactive control; n = 10) Wash‐out period: not applicable (not a cross‐over trial) Details of intervention: no further details Co‐interventions: no description of standard medical treatment
Outcomes	Cardiovascular mortality at 12 months AHI measured by cardiorespiratory monitoring during sleep at 6 months
Notes	Study funding source: not reported Conflict of interest: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "[...] patients with CSA were randomised into two groups." Comment: no further details; insufficient information to judge selection bias.
Allocation concealment (selection bias)	Unclear risk	Quote: "[...] patients with CSA were randomised into two groups." Comment: no further details; insufficient information to judge selection bias.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Insufficient information about measures used to blind participants and professionals.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Insufficient information about measures used to blind the outcome assessors.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No losses to follow‐up reported.
Selective reporting (reporting bias)	Unclear risk	Insufficient information about the study protocol to judge reporting bias.
Other bias	Low risk	The study appears to be free of other sources of bias.

AHI: apnoea‐hypopnoea index; cAHI: central apnoea‐hypopnoea index; CHF: chronic heart failure; CSA: central sleep apnoea; CSB: Cheyne‐Stokes breathing; eGFR: estimated glomerular filtration rate; LVEF: left ventricular ejection fraction; NYHA: New York Heart Association; OSA: obstructive sleep apnoea; RCT: randomised controlled trial; SD: standard deviation.