The effect of frequent or occasional dialysis-associated hypotension on survival of patients on maintenance haemodialysis.
BACKGROUND
While frequent or occasional symptomatic intradialytic hypotension (IDH) may influence patient well-being, its effects on survival-independent of comorbidities-has not previously been investigated. In this study, therefore, our objective was to assess the effect of frequent IDH (f-IDH) or occasional IDH (o-IDH) on survival.


METHODS
During a 10 month run-in period in 1998, 77 patients with f-IDH (> or =10 hypotensive events/10 months, responding only to medical intervention) and 101 patients with o-IDH (1 or 2 events/10 months) were identified among all 958 patients of a dialysis network. Eighty-five patients who had no hypotensive episodes (no-IDH) during this run-in phase served as controls. Patients were followed for a median of 27 months (range: 0.3-37) and survival of patients in the three groups was compared by log-rank test. Independent association of f-IDH and o-IDH with survival, compared with no-IDH, was assessed by a proportional hazards model that included patient demographics, laboratory data and antihypertensive medication as well as comorbidity.


RESULTS
Forty-five patients (58%) with f-IDH, 47 (47%) with o-IDH and 33 (39%) with no-IDH died during the follow-up. Mortality rates (deaths/100 patient years) were 37 (log-rank P = 0.013 vs no-IDH), 26 (log-rank P = 0.375 vs no-IDH) and 21 in the three groups, respectively. This indicates significantly decreased survival in patients with f-IDH as compared to those with no-IDH. In multivariate proportional hazards regression, however, where age, sex, time spent on dialysis, presence of coronary heart disease, diabetes, Kt/V, albumin level and use of beta-blockers, calcium-channel blockers and long-acting nitrates has been adjusted for, neither f-IDH nor o-IDH was associated with survival.


CONCLUSIONS
Mortality in patients with f-IDH is significantly higher than in those without such events. After adjustments for covariates, however, there is no independent effect of frequent or occasional episodes of IDH on mortality.
Tislér
András
A
First Department of Medicine, Faculty of Medicine, Semmelweis University, 2/a Koranyi S., H-1083 Budapest, Hungary. atisler@axelero.hu
Akócsi
Katalin
K
Borbás
Béla
B
Fazakas
László
L
Ferenczi
Sándor
S
Görögh
Sándor
S
Kulcsár
Imre
I
Nagy
Lajos
L
Sámik
József
J
Szegedi
János
J
Tóth
Eszter
E
Wágner
Gyula
G
Kiss
István
I
D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007022:Hypotension / Q000150:complications / Q000209:etiology / Q000401:mortality*; D007676:Kidney Failure, Chronic / Q000150:complications / Q000628:therapy; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis / Q000009:adverse effects*; D016019:Survival Analysis