Relationship between sleep apnoea and mortality in patients with ischaemic heart failure.

OBJECTIVE: To determine whether the influence of sleep apnoea (SA) on the risk of death differs in patients with ischaemic and in those with non-ischaemic heart failure (HF). DESIGN: Prospective observational study. PATIENTS: Consecutive patients with HF with left ventricular ejection fraction < or =45% newly referred to the HF clinic between 1 September 1997 and 1 December 2004. MAIN OUTCOME MEASURES: Patients underwent sleep studies and were divided into those with moderate to severe SA (apnoea-hypopnoea index > or =15/h of sleep) and those with mild to no SA (apnoea-hypopnoea index <15/h of sleep). They were followed up for a mean of 32 months to determine all-cause mortality rate. RESULTS: Of 193 patients, 34 (18%) died. In the ischaemic group, mortality risk adjusted for confounding factors was significantly higher in those with SA than in those without it (18.9 vs 4.6 deaths/100 patient-years, hazards ratio (HR) = 3.03, 95% CI 1.04 to 8.84, p = 0.043). In contrast, in the non-ischaemic HF group, there was no difference in adjusted mortality risk between those with, and those without, SA (3.9 vs 4.0 deaths/100 patient-years, p = 0.929). CONCLUSIONS: In patients with HF, the presence of SA is independently associated with an increased risk of death in those with ischaemic, but not in those with non-ischaemic, aetiology. These findings suggest that patients with ischaemic cardiomyopathy are more susceptible to the adverse haemodynamic, autonomic and inflammatory consequences of SA than are those with non-ischaemic cardiomyopathy.

Cardiovascular autonomic nervous system dysfunction in patients with rheumatoid arthritis and systemic lupus erythematosus.

Although peripheral and central nervous system involvement have been well recognized in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), autonomic nervous system (ANS) involvement has rarely been studied, and has shown conflicting results. We performed cardiovascular ANS assessment in 34 RA and 37 SLE patients, using standard cardiovascular reflex tests. The results in each patient were compared with age- and sex-matched healthy controls. Forty-seven percent of the RA patients and 19% of the SLE patients had symptoms suggesting ANS dysfunction. The heart rate variation in response to deep breathing was significantly decreased in both the RA and SLE patients (p = 0.001). This diminished heart rate response showed no correlation with the disease duration, the number of swollen joints, the Ritchie articular index, ESR, or rheumatoid factor in the RA group, or the disease duration, the SLEDAI score or ESR in the SLE group. The clinical significance of the diminished cardiovascular ANS response needs to be investigated.