Diabetes mellitus and the risk of urinary tract stones: a population-based case-control study.
BACKGROUND
Because nephrolithiasis has been associated with obesity, an important risk factor for type 2 diabetes mellitus (DM), we tested the hypothesis that DM prevalence is increased in individuals who develop renal stones.


METHODS
In an initial electronic analysis, prior diagnoses of DM, hypertension, and obesity were compared between all Olmsted County, MN, residents with a diagnosis code for nephrolithiasis between 1980 and 1999 and matched residents of similar age and sex (N = 3,561 case-control pairs). A random sample of 260 cases and corresponding controls was selected for detailed medical record review to confirm and characterize the stone event and obtain heights, weights, blood pressures, and glucose and cholesterol values.


RESULTS
In the electronic analysis, unadjusted odds ratios (ORs) for DM (OR, 1.29; 95% confidence interval [CI], 1.09 to 1.53), obesity (OR, 1.15; 95% CI, 1.02 to 1.31), and hypertension (OR, 1.19; 95% CI, 1.04 to 1.35) were increased significantly for nephrolithiasis cases versus controls; DM remained significant after adjustment for age, sex, calendar year, hypertension, and obesity (OR, 1.22; 95% CI, 1.03 to 1.46). Detailed record review of a subset showed significant increases for cases versus controls for body mass index (OR, 1.05; 95% CI, 1.01 to -1.09) and hypertension (OR, 1.71; 95% CI, 1.17 to 2.59). Odds for DM were increased, but not significantly, in the subsample (OR, 1.44; 95% CI, 0.76 to 2.72). Among cases with stone analyses, those with uric acid stones (n = 10) had a greater percentage of DM compared with those with all other stone types (n = 112; 40% versus 9%; P = 0.02).


CONCLUSIONS
Findings from this population-based study suggest that DM, obesity, and hypertension are associated with nephrolithiasis, and DM may be a factor in the development of uric acid stones.
Lieske
John C
JC
Department of Internal Medicine, Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, MN 55905, USA. lieske.john@mayo.edu
de la Vega
Lourdes S Peña
LS
Gettman
Matthew T
MT
Slezak
Jeffrey M
JM
Bergstralh
Eric J
EJ
Melton
L Joseph
LJ
Leibson
Cynthia L
CL
D000328:Adult; D016022:Case-Control Studies; D003920:Diabetes Mellitus / Q000453:epidemiology*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D053040:Nephrolithiasis / Q000453:epidemiology*; D009765:Obesity / Q000453:epidemiology; D016017:Odds Ratio; D015995:Prevalence