Patients referred to a nephrologist a year or more before they start dialysis have better odds of survival during the first year of treatment compared with patients who are referred later, even if they have diabetes mellitus or are aged 70 years or older, a study found.
The study, by researchers in The Netherlands, included 1,438 patients with a mean age of 60 years. Of these, 23% had diabetes, 30% were aged 70 years and older, and 62% were male. The investigators, led by Dinanda J. de Jager, MSc, of Leiden University Medical Centre in Leiden, examined patient survival according to the timing of referral (defined as the interval between the first pre-dialysis visit to a nephrologist and dialysis initiation). If the interval was 12 months or more, the referral was considered to be very early, whereas intervals of three to 12 months and less than three months were considered early and late referrals, respectively.
Fifty-six percent of subjects were referred very early, 12% were referred early, and 32% were referred late, according to a report in Nephrology Dialysis Transplantation (2011;26:652-658).
Compared with patients who were referred very early, those who were referred early and late had a 50% and 80% increased risk of death, after adjusting for age, gender, and primary kidney disease.
The researchers also examined the relationship between time of referral and mortality according to diabetes status. Among non-diabetics, those referred early and late had a 1.5 and 2.3 times increased risk of death, respectively, compared with subjects referred very early, after adjusting for gender, age, primary kidney disease, and chronic comorbidities. Among patients with diabetes, subjects referred very early, early, and late had a 2.0, 2.9, and 2.9 times increased risk of death compared with non-diabetics referred very early.
Among patients younger than 70 years, those referred early and late had a nearly twofold increased risk of death compared with patients referred very early. Among subjects aged 70 years and older, those referred very early, early, and late were 2.1, 2.4, and 3.0 times increased risk, respectively, compared with patients younger than 70 who were referred early.
Diabetes or advanced age did not add significantly to the risk of death associated with late referral, the researchers noted.
“Since early referral is beneficial irrespective of diabetic status or age, all dialysis patients should be prepared for dialysis as early as possible,” the authors wrote. “There is no reason to refrain high-risk patients like diabetics and the elderly from timely referral.”