Survival benefit of nephrologic care in patients with diabetes mellitus and chronic kidney disease.
BACKGROUND
The association of nephrologic care and survival in patients with diabetes mellitus and chronic kidney disease is unknown.


METHODS
Using data from 1997 to 2000, we conducted a retrospective cohort study of Veterans Health Administration clinic users having diabetes mellitus and stage 3 or 4 chronic kidney disease. The baseline period was 12 months and median follow-up was 19.3 months. Degree of consistency of visits to a nephrologist, defined as the number of calendar quarters in which there was 1 visit or more (range, 0-4 quarters), and covariates were calculated from the baseline period. The outcome measure was dialysis-free death.


RESULTS
Of 39,031 patients, 70.0%, 22.4%, and 7.6% had early stage 3, late stage 3, and stage 4 chronic kidney disease, respectively, and 3.1%, 9.5%, and 28.2%, respectively, visited a nephrologist. Dialysis-free mortality rates were 9.6, 14.1, and 19.4, respectively, per 100 person-years. More calendar quarters with visits to a nephrologist were associated with lower mortality: adjusted hazard ratios were 0.80 (95% confidence interval, 0.67-0.97), 0.68 (95% confidence interval, 0.55-0.86), and 0.45 (95% confidence interval, 0.32-0.63), respectively, when the groups having 2, 3, and 4 visits were compared with those who had no visits. One visit only was not associated with a difference in mortality when compared with no visits (adjusted hazard ratio,1.02; 95% confidence interval, 0.89-1.16).


CONCLUSIONS
The consistency of outpatient nephrologic care was independently associated in a graded fashion with lower risk of deaths in patients with diabetes and moderately severe to severe chronic kidney disease. However, only a minority of patients had any visits to a nephrologist.
Tseng
Chin-Lin
CL
Department of Veterans Affairs Center for Healthcare Knowledge Management, Department of Veterans Affairs, New Jersey Health Care System, East Orange, NJ 07018, USA. chin-lin.tseng@va.gov
Kern
Elizabeth F O
EF
Miller
Donald R
DR
Tiwari
Anjali
A
Maney
Miriam
M
Rajan
Mangala
M
Pogach
Leonard
L
D000368:Aged; D000369:Aged, 80 and over; D000553:Ambulatory Care; D015331:Cohort Studies; D003920:Diabetes Mellitus / Q000401:mortality* / Q000628:therapy*; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000401:mortality* / Q000628:therapy*; D008297:Male; D009398:Nephrology; D012017:Referral and Consultation; D012189:Retrospective Studies; D015996:Survival Rate