Table 1

Baseline clinical characteristics of patients with type 1 diabetes from the FinnDiane Study, stratified according to 24-h urinary sodium excretion

Quartile
Low, <102 mmol/dayMiddle, 102–187 mmol/dayHigh, >187 mmol/day
Age (years)38 ± 1339 ± 1239 ± 12
Male (%)32.6*49.271.5*
Duration of diabetes (years)22 ± 1222 ± 1220 ± 11*
Insulin dose (units/kg)0.7 ± 0.20.7 ± 0.20.7 ± 0.2
HbA1c (%)8.4 ± 1.58.4 ± 1.58.4 ± 1.4
BMI (kg/m2)24.7 ± 3.4*25.0 ± 3.526.1 ± 3.5*
Hypertension (%)44.5*50.253.6*
Blood pressure (mmHg)
 Systolic132 ± 18133 ± 18135 ± 18*
 Diastolic78 ± 9*79 ± 981 ± 10*
Antihypertensive medication use (%)33.637.139.3*
 ACE inhibition28.927.424.4
 Angiotensin receptor blocker6.25.13.8
 Calcium channel blocker7.38.510.0
 β-blocker9.710.39.0
 Diuretic9.410.08.1
Lipid-lowering therapy (%)10.89.510.8
Cholesterol (mmol/L)
 Total§5.0 ± 0.95.0 ± 0.95.0 ± 1.0
 LDL§3.1 ± 0.83.1 ± 0.83.2 ± 0.8*
 HDL§1.3 ± 0.41.3 ± 0.41.3 ± 0.4*
Triglycerides (mmol/L)1.3 ± 0.91.2 ± 0.91.3 ± 0.9
Any retinopathy (%)525052
Retinopathy requiring laser therapy (%)293128
Current smoker (%)232427
Established macrovascular disease (%)9.27.56.4
Normoalbuminuria (%)68.769.971.1
Microalbuminuria (%)16.414.513.8
Macroalbuminuria (%)14.915.615.2
eGFR (mL/min/1.73 m2)84 ± 2384 ± 2287 ± 21*
  • *Versus middle quartiles, univariate P < 0.05 (for independent predictors of baseline urinary sodium excretion in a multivariate regression model see Supplementary Table 1).

  • §To convert values for cholesterol to milligrams per deciliter, divide by 0.02586.