Sensory impairment in obese patients? Sensitivity and pain detection thresholds for electrical stimulation after surgery-induced weight loss, and comparison with a nonobese population.
BACKGROUND
Obese patients have a high prevalence of painful musculoskeletal disorders that may decrease after massive weight loss. Pain thresholds may be different in obese participants.


OBJECTIVE
To assess the sensitivity and pain detection thresholds, through the application of an electrical sensitivity, before and after massive weight loss, and to compare the thresholds obtained with those in a control population.


METHODS
The sensitivity and pain detection thresholds obtained in participants subjected to electrical stimulation were determined in 31 obese individuals (age: 40.3 ± 10.5 y) before (body mass index: 45.7 ± 6.8 kg/m) and 6 months after a mean weight loss of 32 kg induced by gastric bypass. The results obtained were compared with those for 49 nonobese control participants (38.5 ± 11.2 y; body mass index: 22.6 ± 2.6 kg/m). Body composition and metabolic biomarkers, such as leptin, adiponectin, insulin, and interleukin 6, were assessed and single-nucleotide polymorphisms of the mu opioid receptor [OPRM1 (c.118A > G) and COMT (p.Val158Met)] were genotyped in obese patients.


RESULTS
Sensitivity and pain detection thresholds (3.9 ± 1.1; 11.6 ± 6.0) were significantly higher in obese than in nonobese participants (3.1 ± 1.1; 6.0 ± 3.0), respectively (P < 0.0001), and were not affected by drastic weight loss (mean change: 32 kg). Pain thresholds in obese participants were not correlated with any of the clinical and biological variables studied. The obese participants in the highest quartile for both sensitivity and pain detection thresholds were significantly older than those in the lowest quartile.


CONCLUSIONS
Further studies are required to explore sensory dysfunction in obese individuals and to investigate the implications of this dysfunction for pain management.
Department of Internal Medicine, Assistance Publique-Hôpitaux de Paris, Hôpital Lariboisière, Unit of Therapeutic Research, Paris, France.
Pauline
P
Dodet
Serge
S
Perrot
Lauriane
L
Auvergne
Aline
A
Hajj
Guy
G
Simoneau
Xavier
X
Declèves
Christine
C
Poitou
Jean-Michel
JM
Oppert
Katel
K
Peoc'h
Stéphane
S
Mouly
Jean-François
JF
Bergmann
Célia
C
Lloret-Linares
D000328:Adult; D004558:Electric Stimulation; D005260:Female; D015390:Gastric Bypass / Q000009:adverse effects*; D006801:Humans; D008297:Male; D009767:Obesity, Morbid / Q000150:complications / Q000503:physiopathology* / Q000601:surgery*; D017288:Pain Threshold; D020886:Somatosensory Disorders / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D016896:Treatment Outcome; D015431:Weight Loss