Bradycardia common with CR - human studies

[Guest guest]

>

> http://ajpheart.physiology.org/cgi/content/abstract/263/4/H1021

>

-----------------------------

Well, you don't have to go all the way to rats. There is a sizeable

number of papers out there reporting bradycardia in patients with

anorexia nervosa, and during weight loss diets. Some of it is a bit

scary, since with anorexia, QTc dispersion, a risk factor for

arrhythmias, is also increased. Anorectic patients are usually

potassium deficient, though, so this literature may not apply.

Here is perhaps a more relevant citation that you might explore:

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=pubmed & dopt=Abstra\

ct & list_uids=7501608 & query_hl=7 & itool=pubmed_DocSum

Presse Med. 1995 Sep 23;24(27):1260-2.

[bradycardia during treatments of weight loss]

[Article in French]

Raccah D, Disdier P, Roybet D, Jouglard J, Arditti J, Meunier A, Harle

JR, Weiller PJ, Vague P.

Service de Nutrition et Maladies metaboliques, CHU Timone, Marseille.

Sinus bradycardia was observed in 10 adolescents participating in

a weight loss diet conducted in a health centre. The precise cause was

assessed. The subject's age ranged from 10 to 15 years and weight loss

ranged from 8 to 24 kg over a period ranging from 8 to 23 weeks. None

of the subjects had taken drugs with a bradycardic effect and search

for toxic agents in the blood and urine was negative in all cases.

Infection was suggested since 8 of the 10 adolescents had a

rhinopharyngitis a few weeks before the discovery of bradycardia. This

cause was not retained due to the lack of any signs of infection or

inflammation and negative virus serology. Nutritional status was

therefore retained as the most likely cause in these adolescents who

were eating a diet containing < or = 1350 kcal/day. This hypothesis

was supported by the results of work reported in 1970 showing

arrhythmia in very low calorie diets. The effect is essentially

related to the biological value of proteins in the diet, its duration

and the initial weight of the subjects. In addition bradycardia is

frequently seen in subjects taking hypocaloric diets or with anorexia

nervosa and should be considered as an adaptation to hypometabolism

rather than a true heart disorder. Thus the biological value of the

proteins and the mineral status should be taken into consideration

during the course of low calorie diets, even though bradycardia is

frequent and does not require a specific treatment. Therefore heart

rate and decreasing rate of weight loss should be carefully followed

during the course of low calorie diets.