Effects of alpha-lipoic acid supplementation in peripheral arterial disease: a pilot study.
OBJECTIVE
To examine whether 3 months of lipoic acid (LA) supplementation improved walking tolerance and delayed claudication pain onset in peripheral arterial disease (PAD).


METHODS
Randomized, double-blind, controlled study.


METHODS
General Clinical Research Center.


METHODS
Twenty-eight (28) participants (15 men, 13 women) with PAD (ankle brachial index range 0.9-0.4, mean age 73.2 +/- 1.6 years).


METHODS
LA (600 mg/day) or placebo for 3 months.


METHODS
Walking tolerance was assessed by 6-minute walk test distance, 4-meter walk time, initial claudication pain time (ICT) and distance (ICD), and peak claudication pain. Serum was assessed for inflammation (C-reactive protein [CRP]) and oxidative stress (lipid hydroperoxides) as potential mechanisms for changes in walking tolerance.


RESULTS
ICT increased 34.4% and 15%, ICD was reduced by 40.5% and 18%, and peak claudication pain ratings were reduced by 93% and 7% in LA and placebo groups, respectively. Although the improvements in peak pain and ICT achieved significance within the LA group (both p<0.05), the interactions of group by time were not found to be significant (p>0.05). Oxidative stress and CRP measures were not different between groups by month 3 (p>0.05). There were no serious side-effects associated with the LA.


CONCLUSIONS
LA may confer pain relief during exercise. However, longer and larger trials are warranted to determine long-term effects of LA alone or combined with other interventions on PAD symptoms.
Vincent
Heather K
HK
Center for the Study of Complementary and Alternative Therapies, University of Virginia Health System, Charlottesville, VA, USA. vincehk@ortho.ufl.edu
Bourguignon
Cheryl M
CM
Vincent
Kevin R
KR
Taylor
Ann G
AG
D000368:Aged; D000369:Aged, 80 and over; D000975:Antioxidants / Q000008:administration & dosage*; D015415:Biomarkers / Q000032:analysis; D002097:C-Reactive Protein / Q000032:analysis; D004311:Double-Blind Method; D017079:Exercise Tolerance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D016491:Peripheral Vascular Diseases / Q000188:drug therapy* / Q000517:prevention & control; D010865:Pilot Projects; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D008063:Thioctic Acid / Q000008:administration & dosage*; D016896:Treatment Outcome; D016138:Walking
D000975:Antioxidants; D015415:Biomarkers; D008063:Thioctic Acid; D002097:C-Reactive Protein