Table 3.

Subgroup analysis of the effect of sodium intake reduction on urinary albumin excretion

Variables (No. of Cohorts)	Pooled Mean (%) Reduction	95% Confidence Interval	P Value for Interaction
RAAS-blocking therapya
Yes (11)	−41.9	−56.4 to −27.4	0.01
No (11)	−17.2	−26.1 to −2.1
Length of intervention, wk
>1 (19)	−37.1	−49.3 to −24.9	<0.01
=1 (4)	0.3	−20.2 to 20.8
Country of origin
Europe (16)	−31.4	−44.5 to −18.2	0.70
Australia (7)	−37.1	−70.3 to −3.9
Kidney damage
Yes (16)	−37.3	−49.7 to −24.9	<0.01
No (7)	0.27	−20.0 to 20.6
RCT double blind with placebo
Yes (10)	−22.2	−39.1 to −5.2	0.30
No (13)	−33.1	−46.7 to −19.5
Hypertension status
Yes (14)	−41.9	−54.4 to −29.4	0.20
No (9)	−26.9	−43.8 to −10.0
Diabetes statusa
Yes (11)	−39.5	−57.1 to −21.9	0.40
No (11)	−29.1	−44.8 to −13.3
Risk of bias
Low (14)	−48.8	−58.2 to −39.5	<0.01
High (9)	−18.6	−24.7 to −12.5
Industry funding source
Yes (11)	−34.5	−50.8 to −18.3	0.60
No (12)	−28.0	−48.2 to −7.9
Dietary protocol
Slow sodium (12)	−22.1	−39.0 to −5.3	0.30
Sodium restriction (11)	−33.2	−47.0 to −19.4

RAAS, renin-angiotensin-aldosterone system; RCT, randomized, controlled trial.

^aAnalysis did not include the study by McMahon et al. (30), because there was a mixed antihypertensive therapy and both diabetic and nondiabetic participants were included.