Omega-3 fatty acid prevents heart rate variability reductions associated with particulate matter.
BACKGROUND
Environmental exposure to particulate matter of 2.5 microm or less (PM2.5) has been associated with changes in heart rate variability (HRV).


OBJECTIVE
To evaluate the effect of supplementation with omega-3 polyunsaturated fatty acids on the reduction of HRV associated with PM2.5 exposure.


METHODS
Randomized double-blind trial.


METHODS
Mexico City, Mexico.


METHODS
50 nursing home residents older than 60 yr.


METHODS
Randomization to either 2 g/d of fish oil versus 2 g/d of soy oil as the control, with 6 mo follow-up (1-mo presupplementation and 5-mo supplementation) or repeated HRV measurements. PM2.5 was monitored indoors and outdoors.


METHODS
The association between HRV and 1 SD change in PM2.5 (8 microg/m3).


RESULTS
In the group receiving fish oil, the reduction in HRV-high-frequency log(10)-transformed associated with a 1-SD change in PM2.5 was -54% (95% confidence interval, -72, -24) in the presupplementation phase, and only -7% (95% confidence interval, -20,+7) in the supplementation phase (p < 0.01 for the effect of supplementation), with changes in other HRV parameters also being significantly less pronounced during supplementation. Small decreases in PM2.5-associated reductions in HRV parameters also occurred in the group receiving soy oil, but these were not significant. Fish oil supplementation was significantly better in preventing the reduction in percentage of successive normal RR intervals differing by more than 50 ms (p = 0.03) and the root square of the mean of the sum of the squares of differences between adjacent intervals (p = 0.05) than soy oil supplementation.


CONCLUSIONS
Supplementation with 2 g/d of fish oil prevented HRV decline related to PM2.5 exposure in the study population.
Romieu
Isabelle
I
Instituto Nacional de Salud Pública, Cuernavaca, Mexico.
Téllez-Rojo
Martha Maria
MM
Lazo
Mariana
M
Manzano-Patiño
Abigail
A
Cortez-Lugo
Marlene
M
Julien
Pierre
P
Bélanger
Marie Claire
MC
Hernandez-Avila
Mauricio
M
Holguin
Fernando
F
D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000737:chemistry*; D019587:Dietary Supplements; D004311:Double-Blind Method; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D005260:Female; D005395:Fish Oils / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008297:Male; D008800:Mexico; D009735:Nursing Homes; D010316:Particle Size; D013024:Soybean Oil / Q000494:pharmacology*; D014504:Urban Health
D000393:Air Pollutants; D015525:Fatty Acids, Omega-3; D005395:Fish Oils; D013024:Soybean Oil