Abril - 2017

eripheral

polyneuropathy

severely

obese

patients

with

metabolic

syndrome

but

without

diabetes

: A

ssociation

with

low

HDL-

cholesterol

ssoc

ras

2017; 63(4):324-331

325

ethod

Subjects

A cross-sectional and prospective study including patients

with grade II and III obesity (severe obesity) with MetS

and without diabetes was conducted in the Obesity Treat-

ment Center at Santa Rita Hospital, Santa Casa de Mise-

ricórdia de Porto Alegre Hospital Complex, in the period

of January to December 2014. The studied subjects un-

derwent tests and consultations according to a surgical

protocol to undergo bariatric surgery. Patients were eva-

luated consecutively during their routine visits by two

biomedical examiners who were unaware of the comor-

bidities related to obesity or dyslipidemia and MetS com-

ponents presented by the patients. The following inclusion

criteria were adopted: minimum age of 18 years; grade II

and III obesity as defined by the World Health Organiza-

tion (WHO)

(BMI ≥ 35 to 39.9 g/m

and BMI ≥ 40 kg/

, respectively); MetS as defined by the International

Diabetes Federation (IDF);

absence of DM according to

parameters of the American Diabetes Association (ADA);

and consent form signed for participation in the study.

Exclusion criteria were: hypothyroidism (TSH levels grea-

ter than 6 mU/L); vitamin B12 deficiency (serum levels

below 210 pg/mL); prior bariatric surgery; history of al-

cohol abuse according to the CAGE questionnaire;

crea-

tinine clearance less than 60 mL/min according to the

Cockcroft-Gault equation;

acute liver disease; leprosy;

HIV positive test; nursing mothers and pregnant women;

fasting glucose or A1c hemoglobin levels suggesting diag-

nosis of DM on the date of inclusion.

The following information was obtained from the

patients’ medical charts in the last three months of as-

sessment for neuropathy: anthropometric data and blood

pressure (mmHg), serum blood glucose (mg/dL) checked

after fasting and again two hours after drinking a glu-

cose-rich drink, HDL-cholesterol (mg/dL), LDL-choles-

terol (mg/dL), triglycerides (mg/dL), creatinine (mg/dL),

TSH (mU/L), and vitamin B12 (pg/mL). After authorizing

their participation in the study, patients were asked to

complete the questionnaire, which comprised questions

regarding presence of neuropathy – the MNSI.

9,10

The first

measures assessed were degree of neuropathy according

to the MNSI and waist circumference. Impaired glucose

intolerance was defined according to the ADA criteria.

Metabolic syndrome was characterized according to

the IDF criteria,

and was considered present with waist

circumference ≥ 80 cm for women and ≥ 94 cm for men

in addition to at least two of the following risk factors:

triglycerides ≥ 150 mg/dL, HDL-cholesterol < 40 mg/dL

for men and < 50 mg/dL for women, systolic blood pres-

sure ≥ 130 mmHg or diastolic blood pressure ≥ 85 mmHg,

fasting glucose ≥ 100 mg/dL, previous diagnosis of DM

and hypertension or patient undergoing treatment for

hypertension or DM.

LDL-cholesterol was defined as increased if > 130mg/dL,

fasting blood glucose ≥ 100mg/dL and < 126mg/dL was cat-

egorized as impaired glucose tolerance (IGT),

blood glucose

2 hours after oral intake of 75 g of glucose ≥ 140 mg/dL

and < 200 mg/dL was defined as IGT,

and creatinine

> 1.4 mg/dL was defined as chronic renal disease.

Of the 315 patients, 67 were excluded for having dia-

betes, 23 for not meeting the criteria for MetS, three for

having hypothyroidism, three for having had bariatric

surgery in the past and one for having vitamin B12 defi-

ciency. In the end, 218 individuals remained in the study.

Ethical aspects

The study was approved by the Research Ethics Commit-

tee of the Santa Casa de Misericórdia de Porto Alegre

Hospital Complex and all patients were informed about

this research through a Free and Informed Consent Form,

according to resolution 466/2012.

Instruments

MNSI was used to assess the presence and degree of neu-

ropathy.

9,10

This instrument was validated and yielded a

specificity of 79% and a sensitivity of 61%.

The MNSI questionnaire for symptoms consists of

15 questions, which were translated into Brazilian Portu-

guese and used to track PPN symptoms. The maximum

amount of points scored by patients was 13, since ques-

tions 4 and 10 serve to assess association with peripheral

vascular disease and asthenia, respectively.

The MNSI physical examination was conducted in a

comfortable and calming room of the OTC, with tem-

perature ranging between 22ºC and 26ºC. The patients

remained seated or at supine position lying comfortably

and blindfolded in order to raise the perception. A physi-

cian of our team was trained to perform this test at the

University of Michigan, further instructing two of our PhD

students on performing this neurological evaluation. These

two biomedical scientists performed all of the tests and in

case of discrepancies the physician also examined the patient

and made the final decision. Examiners were blinded for

the results of laboratory exams while performing the phys-

ical examination. In the physical exam, points were award-

ed according to results of appearance of feet, vibratory

sensitivity on the hallux, sensitivity to Semmes-Weinstein

monofilament applied in the same location of the tuning

fork, and blow with a neurological hammer on the Achilles