Oral creatine supplementation: A potential adjunct therapy for rheumatoid arthritis patients

Table 1 Summary of the results from the meta-analysis by Nissen et al[37]

Supplement(n = studies)	Average dosage (maintenance dose)	Duration(wk)	Net leanmass change	Net strength change
Cr (n = 18)	19.4 g/d for 5.3 d (6.7 g/d)	7.5	+0.36%/wkb	+1.09%/wkb
HMB (n = 9)	3 g/d	8	+0.28%/wkb	+1.40%/wkb
Chromium (n = 12)	485 μg/d	11.2	+0.08%/wk	+0.25%/wk
Androstenedione (n = 3)	200 mg/d	10.7	+0.05%/wk	-0.06%/wk
Protein (n = 4)	1.15 g/kg per day	6.3	+0.12%/wk	-0.18%/wk
DHEA (n = 2)	125 mg/d	10	+0.12%/wk	+0.06%/wk

The net change is expressed as % change per week. Only Cr and HMB resulted in significant changes;

^bP < 0.005. Cr: Creatine; HMB: β-hydroxy-β-methylbutyrate; DHEA: Dehydroepiandrosterone.

Table 2 Changes in creatine and phosphocreatine levels following Cr supplementation

	Mean baseline Cr levels1	Increase after20 g/d for 5 d
Creatine	Approximately 125 mmol· kg/dw[130] (90 to 160 mmol· kg/dw)[4]	+ 25 mmol· kg/dw (approximately 20%)[144]
Phosphocreatine	Approximately 50 mmol· kg/dw[41]	+ 8 mmol· kg/dw (approximately 15%)[132]

¹Typical values for an average 70 kg male. Cr: Creatine.

Table 3 Summary of studies investigating the effects of creatine supplementation on sarcopenia and function in older adults over 60 years

Treatment arm(mean age ± SD)	Supplementation period	Study design	Body composition changes	Physical function changes	Ref.
10 males (66.7 ± 1.9 yr)	20 g/d for 10 d followed by 4 g/d for 20 d	vs PL group (dextrose) (n = 10)	2Body density, 2LM, 2%BF	1Leg fatigue performance	[99]
9 males (65.0 ± 2.1 yr)	20 g/d for 5 d	vs PL group (sucrose) (n = 8)	1BM, 2LM	2Strength	[100]
10 females (67.0 ± 6.0 yr)	0.3 g per kg/day for 7 d	vs PL group (n = 6)	No details	1Objective function tests, 2Endurance capacity	[97]
10 males (65.4 ± 1.5 yr)	0.3 g per kg/day for 7 d	vs PL group (powdered cellulose) (n = 8)	1BM, 1LM	1Strength, 1Power, 1Objective function tests	[55]
15 females (63.3 ± 1.2 yr)	0.3 g per kg/day for 7 d	vs PL group (powdered cellulose) (n = 12)	1BM, 1LM, 2%BF	1Strength, 1Objective function tests	[98]
7 males and 8 females (74.5 ± 6.4 yr)	20 g/d for 7 d followed by 10 g/d for 7 d	Cross-over design	2BM	1Strength, 1Endurance (cycling capacity at fatigue threshold), 2Objective function tests	[101]
7 males (72.5 ± 2.5 yr)	20 g/d for 5 d	vs PL group (maltodextrin) (n = 5)	1BM, 2LM	2MVC or contractile force	[102]
4 males and 4 females (71.0 ± 1.9 yr)	20 g/d for 5 d followed by 3 g/d for 8 wk	vs PL (glucose) (n = 8)	2Lower limb volume, 2BM, 2%BF	2Strength 2Endurance	[103]
15 females (66.1 ± 4.8 yr)	20 g/d for 5 d followed by 5 g/d for 23 wk	vs PL (dextrose) (n = 15)	1LM, 2FM	1Strength 1Objective function tests	[104]

¹Significant increase/improvement;

²No significant change (^aP < 0.05 for interaction between placebo and Cr group). Cr: Creatine; PL: Placebo; BM: Body mass; %BF: Percent body fat; FM: Fat mass; LM: Lean mass; MVC: Maximal voluntary contraction; No details: No details are specified or this measure was not made.

Table 4 Summary of clinical trials investigating the effects of creatine supplementation on body composition and physical function

Condition	Treatment arm	Supplementation period	Control arm	Body composition changes	Physical function changes	Other effects	Ref.
Osteoarthritis	n = 18	10 g/d pre surgery; 5 g/d for 30 d post-surgery	vs PL (n = 19) (dextrose)	2% BF, 2FM, 3LM (CSA), 3BW	3Strength	3PCr	[106]
Fibromyalgia	n = 16	20 g/d for 5 d followed by 5 g/d for 16 wk	vs PL (n = 16) (dextrose)	Not measured	1Strength	3QoL scores, 3Pain, 3Cognition, 1PCr	[109]
Cancer (cachexia)	n = 16 (colorectal cancer)	20 g/d for 5 d followed by 5 g/d for 8 wk	vs PL (n = 15) (cellulose)	3LM	1Strength	3QoL scores	[118]
	n = 9 (adolescents with leukaemia (acute lymphoblastic)	2 sets of 8 wk (with a 6 wk wash out in-between)	vs control “natural history group” (n = 50)	3LM, 2%BF	No details	3Bone mineral content	[119]
Duchenne muscular dystrophy	n = 18 (adolescents)	5 g/d for 8 wk	vs PL (n = 15) (vitamin C)	No details	1Strength	1PCr	[113]
	n = 15 (adolescents)	5 g/d for 24 wk	vs PL (n = 16) (cocoa powder)	No details	3Strength, 3Objective function tests		[116]
	n = 30 (adolescents)	0.10 g per kg/d for 16 wk	Cross-over design (PL group dextrose)	1LM	1Strength	2Bone breakdown markers	[112]
	n = 15 (adolescents) (12 with DMD and 3 with Becker dystrophy)	3 g/d for 13 wk	Cross-over design (PL group maltodextrin)	No details	1Strength (MVC), 1Fatigue resistance		[62]
Mytonic muscular dystrophy 1 (DM1)	n = 34	5 g/d for 36 wk	Cross-over design (PL group dextrose)	3LM	3Strength, 3Objective function tests		[115]
	n = 34	10.6 g/d for 10 d followed by 5.3 g/d for 45 d	Cross-over design (PL group cellulose)	3LM	3Strength	3ADL, 3QoL scores	[114]
Mytonic muscular dystrophy 2 (DM2)	n = 10	10 g/d for 13 wk	vs PL (n = 10)	No details	3Strength	3QoL scores	[117]

¹Significant increase/improvement;

²Significant decrease/reduction;

³No significant change (^aP < 0.05 for interaction between placebo and Cr group). Cr: Creatine; PL: Placebo; CSA: Cross sectional area; ADL: Activities of daily living; PCr: Phosphocreatine; QoL: Quality of life; MVC: Maximal voluntary contraction; BM: Body mass; FM: Fat mass; LM: Lean mass; PRT: Progressive resistance training; No details: No details are specified or this measure was not made.