IMPACTS OF OBESITY ON PAIN THRESHOLD, DEPRESSION AND

Acta Medica Mediterranea, 2015, 31: 43
IMPACTS OF OBESITY ON PAIN THRESHOLD, DEPRESSION AND QUALITY OF LIFE
AFITAP ICAGASIOGLU¹, SELIN TURAN TURGUT², RAIFE SIRIN ATLIG³, SENEM SENTURK4, AYTEKIN OGUZ5, ERKAN MESCI1
¹Medeniyet University Goztepe Training and Research Hospital, Department of Physical Medicine and Rehabilitation, Istanbul ²Karaman State Hospital, Department of Physical Medicine and Rehabilitation, Karaman - ³Avicenna Umut Hospital, Department of
Physical Medicine and Rehabilitation, Istanbul - 4Medeniyet University Goztepe Training and Research Hospital, Department of
Radiology, Istanbul - 5Medeniyet University Goztepe Training and Research Hospital, Department of Internal Medicine, Istanbul,
Turkey
ABSTRACT
Introduction: Obesity can effect pain threshold, emotional mood and quality of life. Differences in pain thresholds and emotional mood may have implications for pain and depression management. The aim of this study was to assess the effects of obesity on
pain threshold, depression and quality of life.
Materials and methods: This study was designed as a cross-sectional observational study and carried out on 80 adult obese
and nonobese people aged between 18 and 40 years who were admitted to the obesity and metabolic syndrome outpatient clinics. The
subcutaneous adipose tissue thickness was measured for rectus femoris, triceps muscle, and umbilicus by using ultrasonography.
The pressure pain thresholds in 3 muscles including the deltoid, tibialis anterior, and first interosseus dorsalis muscle of the hand
were measured by using a digital pressure algometer. The subjects were evaluated by visual analogue scale (VAS) when a pressure
was applied on the first distal phalanx (FDP) at a rate of 25 Newton. Depression levels of the subjects were evaluated by the Beck
Depression Inventory (BDI). Quality of life was evaluated by Short Form 36 (SF-36).
Results: The mean pain threshold values showed no statistically significant difference between groups (p>0.05). The mean
values of adipose thickness were significantly higher in the obese group (p<0.01). No statistically significant difference was determined between the groups in terms of FDP VAS scores (p>0.05). The obese group had significantly higher BDI scores than the control
group(p<0.01). All parameters of SF-36 were significantly lower in obese individuals(p<0.01).
Conclusions: Our findings suggest no significant correlation between obesity and pain threshold. But we found strong relationship between obesity and both for depression and quality of life
Key words: Obesity, pain threshold, quality of life, depression.
Received May 18, 2014; Accepted September 02, 2014
Introduction
Obesity, defined by the World Health
Organization as a global pandemic, is a chronic disease that occurs as a result of various interactions
between genetic inheritance and environmental factors, and it is recognized as an important public
health issue across the world, particularly in
Western countries. While obesity may lead to serious diseases such as hypertension, type 2 diabetes
mellitus, dyslipidemia, coronary artery diseases,
stroke, sleep apnea, cancers, it may also result in
pain(1).
Obesity can effect pain threshold, emotional
mood and quality of life. However studies about
this subject produced contradictory results.
Pain threshold is the level of stimulus at which
the subject begins to feel pain or discomfort (2).
Various researches on different populations show
that many factors are involved in the process of
pain communication. Factors such as environment,
age, gender, ethnic, genetic and hormonal differences, and psychosocial levels may affect pain
responses(3). Assessment of the pain status is often
built upon the patient self-report, since pain is a
subjective perception.
44
The patient self-report provides the most valid
measure of pain, and is considered as the gold standard in pain assessment(4). There are a large number
of pain measurement instruments that have been
developed. The pressure algometer is one of them,
which has been designed to measure deep pressure
pain thresholds or tenderness resistance, and it is
known to be a reliable instrument in this regard(5).
Previous studies suggest that obesity can affect pain
threshold due to changes in the endocrine metabolism and endogenous opiates. However, these studies have produced contradictory results(6,7).
Differences in pain thresholds may have implications for pain manegement, as they may account
in part for the variability in analgesic requirements
between individuals. In obese patients, pain thresholds would make it possible to predict the need for
prescriptions of drugs with a narrow therapeutic
margin, such as morphine(8).
Obesity has been shown to affect emotional
mood and increase depressive complaints (9) .
Furthermore, obesity has a significant impact on
health, psychosocial well-being, and quality of
life(10).
The aim of this study was to assess the effects
of obesity on pain threshold, depression and quality
of life.
Material and method
This cross-sectional observational clinical trial
was in accordance with the Second Declaration of
Helsinki and performed after obtaining approval
from the local ethical committee of Medeniyet
University Goztepe Training and Research Hospital
and receiving written informed consent from the
patients.
This study was carried out on 80 adult obese
and nonobese men and women aged between 18
and 40 years who were admitted to the obesity and
metabolic syndrome outpatient clinic.
While obese patients (n=40) were recruited
from obesity and metabolic syndrome outpatient
clinics, healthy hospital staff were recruited as
nonobese subjects (n=40). None of the subjects had
any complaint of pain and they were not taking any
analgesics at the time of inclusion. Nonobese subjects had a body mass index (BMI) of <30 kg/m2,
unremarkable physical examination results, and no
history of any major illness, as well as showing no
sign of any disorders in the laboratory tests or radiography.
Afitap Icagasioglu, Selin Turan Turgut et Al
Obese patients had a BMI of >30kg/m2 with
no severe and uncontrolled diseases related to obesity such as hypertension, uncompensated diabetes,
polyneuropathy, as well as major cardiovascular,
respiratory, neuromuscular or orthopedic diseases.
The subcutaneous adipose tissue thickness was
measured for rectus femoris muscle, triceps muscle,
and umbilicus by a radiologist using ultrasonography (Mindray DC-7T) with a linear transducer of 412 mHz frequency.
The pressure pain thresholds in 3 muscles
including the insertion of the deltoid muscle, half of
the tibialis anterior muscle, and first interosseus
dorsalis muscle of the hand were measured bilaterally three times by using a digital pressure algometer (Storz Medical F-meter version 5.0). The same
physiatrist applied the pressure algometer and the
rate of force application was constant. The data
concerning the pressure pain threshold were the
average values of six measurements per side. The
subjects were evaluated by visual analogue scale
(VAS) by asking them to indicate which point along
the line best represented their pain intensity when a
pressure was applied on the first distal phalanx
(FDP) at a rate of 25 Newton, bilaterally.
Depression levels of the subjects were evaluated by the Beck Depression Inventory (BDI).
Quality of life was evaluated by Short Form
36 (SF-36).
Statistical analysis was performed with NCSS
2007&PASS 2008 Statistical Software (Utah,
USA). Descriptive variables were presented as
mean ± standard deviation (SD), and Student’s t test
was used for continuous variables. Mann-Whitney
U test was applied for non-normally distributed
data. Yates’ Continuity Correction and Pearson Chisquare tests were used for qualitative variables. The
significance level was set at p<0,05 for all statistical procedures.
Results
Eighty patients were enrolled the study. There
was no statistically significant difference between
the groups with regard to age and gender (p>0.05).
The BMI and waist circumference values of the
obese patients were significantly higher than those of
the control group (p<0.01) (Table 1).
No statistically significant difference was determined between the groups in terms of FDP VAS
scores (p>0.05).
Impacts of obesity on pain threshold, depression and quality of life
Obese (n=40)
Nonobese(n=40)
+p
Mean(SD)
Mean(SD)
Age (year)
30.5(6.9)
29.0(4.3)
0.254
Height (cm)
164.3(9.3)
166.6 (7.4)
0.233
Weight (kg)
89.0 (17.2)
62.4(8.5)
0.001**
BMI (cm/kg2)
32.8(5.2)
22.3(1.7)
0.001**
Waist circumference (cm)
109.7(14.9)
85.9(5.9)
0.001**
n (%)
n (%)
++p
Female
29.0 (72.5%)
31.0 (77.5%)
Male
11.0 (27.5%)
9.0 (22.5%)
Gender
0.796
45
significantly higher in the obese group than in the
control group (p<0.01).
The mean pain threshold values of the deltoid,
tibia, and first interosseus muscles showed no statistically significant difference between the groups
(p>0.05) (Table 2).
The groups manifested a strong statistically significant difference relative to SF-36 scores (p<0.01).
The mean scores of physical functioning, physical
role functioning, pain, general health perceptions,
vitality, social role functioning, emotional role functioning, and mental health were significantly lower
in obese individuals (Table 3).
Table 1: Characteristics of groups.
Obese (n=40)
** P<0,05 Values are expressed as the mean (SD) or number
(n). There were no significant differences between the groups
with regard to age and gender.The BMI and waist circumferenec values of obese patients were significantly higher than control group.
Obese (n=40)
Nonobese (n=40)
P
Mean(SD)
Mean(SD)
FDP VAS
5.6(2.7)
6.1(2.2)
0.425
BDI
15.9(9.6)
5.7(4.7)
0.001**
Subcutaneous fat tissue thickness
Quadriceps
13.6(6.1)
9.9(2.2)
0.002**
Umbilical
35.6(11.3)
18.1(6.8)
0.001**
Triceps
13.8(6)
9.4(2.4)
0.001**
Pain threshold
Deltoid
26.3(9.9)
26.6(9.6)
0.891
Tibialis anterior
29.9(11.9)
33.0(9.2)
0.206
First dorsal interosseus
28.5(9.7)
26.9(8.2)
0.408
Table 2: Distribution of measurements relative to the
groups.
** P<0,05. Values are expressed as the mean (SD) or number
(n). No statistically significant difference was determined
between the groups in terms of FDP VAS scores. The obese
group had significantly higher BDI scores than the control
group.The mean values of adipose thickness were significantly
higher in the obese group than in the control group.The mean
pain threshold values showed no statistically significant difference between the groups
The groups demonstrated a statistically significant difference regarding the BDI scores (p<0.01).
The obese group had significantly higher BDI scores
than the control group.
The mean values of adipose thickness for triceps muscle, quadriceps muscle, and umbilicus were
Control (n=40)
p
Mean(SD)
Physical functioning
Mean(SD)
77.0( 21.8)
93.0 (11.8)
0.001**
Physical role
functioning
55.6 ( 46.5 )
91.2( 25.0)
-100
0.001**
Pain
66.1 ( 28.4)
84.4 ( 18.2)
0.001**
General health
perceptions
47.5 ( 5.5)
51.5 ( 4.6)
0.001**
Vitality
48.0 (21.9)
65.0 (15.8)
0.001**
Social role functioning
48.7 (9.7)
91.8 (15.1)
0.001**
Emotional role
functioning
50.8( 46.5 )
83.3 ( 32.0)
-100
0.001**
Mental health
61.0 ( 17.3)
74.9 (12.0)
0.001**
Table 3: SF-36 scores relative to the groups.
** P<0,05. Values are expressed as the mean (SD) or number
(n). The all mean scores of SF-36 were significantly lower in
obese individuals.
Discussion
The literature on the impact of obesity over
pain threshold is limited with contradictory results.
Some of these studies note that obesity reduces the
pain threshold, while others show exactly the opposite(11-20). Although the exact underlying mechanism
of the relationship between obesity and pain threshold is not known, it is projected that obesity may
impact pain threshold via endogenous opiates,
endocrine hormones such as leptin and ghrelin, as
well as peripheral factors such as adipose tissue
thickness.
Kutlu et al.(12) measured the pain threshold in
mice that underwent leptin injection by using hot
plate analgesy-meter and found lower pain threshold
values in the leptin group than in the control group.
They noted that leptin may have an influence on pain
threshold by affecting the secretion of neuroen-
46
docrine factors associated with nociception such as
beta-endorphin and alpha-melanocyte stimulating
hormone.
McKendall et al.(13) conducted a study based on
the hypothesis claiming that analgesic opiates are
increased in obesity. They applied a constant pressure of approximately 3 pounds to the tip of the
thumb on 56 obese and nonobese patients in order to
measure the time interval until the first sensation of
pain. However, contrary to the expectations, the
obese patients were found to be more sensitive to
pain.
Miscio et al(14) evaluated vibration pain threshold and compared motor and sensory nerve conduction in obese patients and nonobese participants.
They found that pain thresholds and vibration sensitivity were lower in obese group. Despite these significant differences between obese and nonobese
group, they found no direct correlation between BMI
and thresholds or vibration sensitivity. They suggested that pain signals may be modulated by the thickness of subcutaneous tissue.
Roane et al.(15) used tail pinch or tail flick pain
stimulation tests and found that Zucker rats were
more sensitive to pain. Ramzan et al.(16) employed hot
water as a pain stimulant on obese and nonobese rats
before measuring the pain threshold by tail flick test
and found that tail flick latency was 30% higher in
obese rats.
Ensari et al.(17) thought that decreasing ghrelin
levels in obesity might have an impact on pain sensitivity. Ghrelin was noted to have an excitatory effect
on neurons containing endogenous opioid, reduce
pain via its anti-inflammatory influence, and act as
an antinociceptive agent in association with the
endocannobioid system.
Zahorska-Markiewicz et al.(18) tested pain sensitivity using electrophysiologic method on 35 obese
female patients and determined significantly high
sensory and pain thresholds in obese women.
Similarly, Pradalier et al.(19) conducted a study based
on the opinion that the pain threshold in morbidly
obese patients who underwent an operation might be
higher and found a lower need for postoperative narcotic analgesics.
Khimich (20) evaluated the pain threshold of
patients using pin prick test and found that obese
women were less sensitive to pain than normal
women and women with a low BMI.
Obese patients with a binge-eating disorder
have been observed to have higher pain threshold
values than normal individuals and obese patients
Afitap Icagasioglu, Selin Turan Turgut et Al
with no binge-eating disorder. This remarkable difference was associated with the antinociceptive
response generated by excessive vagal activation in
binge-eating disorder(21). Maffiuletti et al.(22) evaluated
motor and sensory excitability threshold, and found
higher values in obese patients than in nonobese
individuals. They assessed the maximal pain perceived during the procedure by VAS and determined
no significant difference between the groups.
Dodet P. et al(23) assessed the sensitivity and pain
detection threshols through the application of an
electrical sensitivity, before and after massive weight
loss, and compared the thresholds with those in a
normal-weighted control population. They also
assessed body composition, metabolic biomarkers
(leptin, adiponectin, insulin and interleukin (IL-6))
and genetic analyses’ of participiants. Although they
found that sensitivity and pain thresholds were significantly higher in obese than in nonobese group,
sensory dysfunction and pain thresholds were not
correlated with weight loss, hormonal and genetic
factors.
In this study, no statistically significant correlation was found between obesity and pain threshold.
Many of the aforementioned studies on humans
involve low number of cases and wide range of age.
Furthermore, they do not mention whether the
patients had pain before the test or had any disease
that would cause pain. In addition, these studies have
applied only one measurement from only the upper
extremities. The contradictory results may be
explained by these factors.
In our study, the patients had no pain or any disease that would cause pain before the tests. By
selecting patients from a younger age group, presence of clinical pain associated with advanced age
was removed. Bilateral pain threshold measurements
were carried out three times by a digital algometer
from both upper and lower extremities and the mean
value of those 3 tests were used in the study.
Ultrasonography is known to be a valid modality in the measurement of visceral and abdominal
subcutaneous adipose tissue as compared with magnetic resonance imaging (MRI) and skinfold
caliper(24).
Nordander et al.(25) measured the thickness of
subcutaneous adipose tissue over trapezius muscle
by ultrasonography and evaluated the excitability of
the trapezius muscle using surface electromyography. They found a significant decrease in electromyography amplitudes in response to increasing
thickness of subcutaneous adipose tissue.
Impacts of obesity on pain threshold, depression and quality of life
However, they did not mention pain threshold
or sensitivity in their study.
Maffiuletti et al.(22) reported a moderate level of
negative correlation between thickness of subcutaneous adipose tissue and sensory threshold, whereas
they found a significant decrease in motor excitability threshold.
In our study, BDI scores were significantly
higher in the obese group than in the nonobese
group, whereas all the parameters of SF-36 were
found to be significantly decreased in the obese
group.
Previous studies in the literature indicate a relationship between obesity and depression. However, it
has not yet been clarified whether obesity causes
depression, or depression triggers obesity. Both
depression and obesity (also recognized as a lowgrade inflammation) are associated with increased
levels of certain cytokines such as IL-6, C-reactive
protein (CRP), and tumor necrosis factor-alpha
(TNF-α)(26,27). There is not much data about the biological mechanisms suggestive of a relationship
between depression and inflammation. Some studies
claim that depressive mood is a result of inflammation and that inflammation can aggravate depressive
symptoms(27).
Milaneschi et al.(28) evaluated the thickness of
abdominal adipose tissue and plasma leptin levels of
1220 male and 1282 female patients by computerized tomography, while assessing their emotional
conditions with Center for Epidemiological StudiesDepression (CES-D) scale; they found that depressive symptoms increased with obesity.
Kim et al.(29) evaluated the quality of life among
obese and nonobese patients and found that it was
lower in obese patients.
Dinc et al(30) studied 1602 female patients of
reproductive age (15-49 years) in terms of obesity
and quality of life. They evaluated the quality of life
with the abbreviated version of WHO Quality of Life
Questionnaire (WHOQOL-BREF) and determined a
negative linear association between BMI and WHOQOL-BREF scores.
Doll et al.(31) interviewed 8889 patients who presented to the hospital and evaluated the quality of life
via SF-36. They found that high BMI values affected
the quality of life in a negative way.
Our findings suggest no significant correlation
between obesity and pain threshold. But we found
strong relationship between obesity and both for
depression and quality of life.
47
Our study has some limitations.We had only
a small number of cases and used only one technique (pressure algometer) to assess the pain
thresholds. Finally, patients were included from
one region in Turkey, and our results may not be
generalizable.
References
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
11)
12)
13)
14)
15)
16)
Bray GA. Risk of obesity. Endocrinol Metab Clin North
Am. 2003, 32: 787-804.
Turk DC, Kerns RD. Conceptual issues in the assessment of clinical pain. Int J. Psychiatry Med. 1984; 13:
57-68.
Fillingim RB. Individual differences in pain responses.
Curr Rheumatol Rep 2005; 7: 342-7.
Turk DC, Melzack R. The measurement of pain and the
assessment of people experiencing pain. In Turk DC,
Melzack R. (eds). Handbook of Pain Assessment.
Guilford Press, New York, 1992: 3-14.
Kinser AM, Sands WA, Stone MH. Reliability and
validity of pressure algometer. Journal of Strenght and
Conditioning Research 2009; 23: 312-4.
Broberger C. Brain regulation of food intake and
appetite: molecules and networks. J Int Med 2005; 258:
301-27.
Cowley MA, Smith RG, Dano MS, Tschöp M,
Pronchuk N et al. The distribution and mechanism of
action of ghrelin in the CNS demonstrates a novel
hypothalamic circuit regulating energy homeostasis.
Neuron 2003; 37: 649-61.
Lloret Linares C, Declèves X, Oppert JM, Basdevant
A, Clement K et al. Pharmacology of morphine in
obese patients: clinical implications. Clin
Pharmacokinet. 2009; 48: 635-51.
Milaneschi Y, Simonsick EM, Vogelzangs N,
Strotmeyer ES, Yaffe K et al. Leptin, abdominal obesity
and onset of depression in older men and women. J
Clin Psychiatry. 2012; 73: 1205-11.
Kolotkin RL, Meter K, Williams GR. Quality of life
and obesity. Obesity reviews 2001; 2: 219-29.
Zahorska-Markiewicz B, Kucio C, Pyszkowskaj.
Obesity and pain. Hum Nutr Clin Nutr 1983; 37: 30710.
Kutlu S,Canpolat S, Sandal S ,Ozcan M, Sarsilmaz M
et al. Effects of central and peripheral administration
of leptin on pain threshold in rats and mice.
Neuroendocrinol Lett. 2003; 24: 193-6.
Mc Kendall MJ, Haier RJ. Pain sensitivity and obesity.
Psychiatry Research 1983; 8: 119-25.
Miscio G, Guastamacchia G, Brunani A, Priano L,
Baudo S et al. Obesity and peripheral neuropathy risk:
a dangerous liaison. J Peripher Nerv Syst. 2005; 10:
354-8.
Roane DS, Porter JR. Nociception and opioid-induced
analgesia in lean (Fa/-) and obese (fa/fa) Zucker rats.
Physiology Behavior 1986; 38: 215-8.
Ramzan I, Wong BK, Corcaron BG. Pain sensitivity in
dietary-induced obese rats. Physiology Behavior 1993;
54: 433-5.
48
17)
18)
19)
20)
21)
22)
23)
24)
25)
26)
27)
28)
29)
Afitap Icagasioglu, Selin Turan Turgut et Al
Ensari G, Gumustekin M, Ates M. Possible involvement of ghrelin on pain threshold in obesity. Medical
Hypotheses 2010; 74: 452-4.
Zahorska-Markiewicz B, Zych P, Kucio C. Pain sensitivity in obesity. Acta Physiol Pol 1988; 39: 183-7.
Pradalier A, Dry J, Willer JC, Boureau F. Obesite et
baisse du seuil nociceptif. Pathol Biol. 1980; 28: 462-4.
Khimich S. Level of sensitivity of pain in patients with
obesity. Acta Chir Hung 1997; 36: 166-7.
Raymond NC, de Zwaan M, Faris PL, Nugent SM,
Achard DM et al. Pain thresholds in obese binge-eating disorder subjects. Biol Psychiatry 1995; 37: 202-4.
Maffiuletti NA, Morelli A, Martin A, Duclay J, Billot
M et al. Effects of gender and obesity on electrical current thresholds. Muscle Nerve 2011; 44: 202-7.
Dodet P, Perrot S, Auvergne L, Hajj A, Simoneau G et
al. Sensory impairment in obese patients? Sensitivity
and pain detection thresholds for electrical stimulation
after surgery-induced weight loss, and comparison with
a nonobese population. Clin J Pain. 2013; 29: 43-9.
De Lucia Rolfe E, Sleigh A, Finucane FM. Ultrasound
measurements of visceral and subcutaneous abdominal
thickness to predict abdominal adiposity among older
men and women. Obesity 2010; 18: 625-31.
Nordander C, Willnerr J, Hansson GA, Larsson B,
Unge J et al. Influence of subcutaneous fat layer, as
measured by ultasound, skinfold calipers and BMI, on
the EMG amplitude. Eur J Appl Physiol 2003; 89: 5149.
Iannone F, Lapadula G. Obesity and Inflammation Targets for OA Therapy. Current Drug Targets, 2010,
11, 586-98.
Elovainio M, Aalto AM, Kivimäki M, Pirkola S,
Sundvall J et al. Depression and C-reactive protein:
population-based health 2000 study. Psychosomatic
Medicine 2009; 71: 423-30.
Milaneschi Y, Simonsick EM, Vogelzangs N,
Strotmeyer ES, Yaffe K et al. Leptin, abdominal obesity, and onset of depression in older men and women. J
Clin Psychiatry. 2012 ;73: 1205-11.
Kim CH, Luedtke CA, Vincent A, Thompson JM, Oh
TH. Association of body mass index with symptom
severity and quality of life in patients with fibromyalgia. Arthritis Care Res (Hoboken). 2012; 64: 222-8.
30)
31)
Dinc G, Eser E, Saatli GL, Cihan UA, Oral A et al. The
relationship between obesity and health related quality
of life women in a Turkish city with a high prevalence
of obesity. Asia Pac J Clin Nutr 2006; 15: 508-15.
Doll HA, Petersen SE, Stewart-Brown SL. Obesity and
physical and emotional well-being: associations
between body mass index, chronic illness, and the physical and mental components of the SF-36 questionnaire. Obes Res. 2000; 8: 160-70.
_________
Correspoding author
AFITAP ICAGASIOGLU
Istanbul Medeniyet University Goztepe Training and Research
Hospital, Department of Physical Medicine and Rehabilitation
Fahrettin Kerim Gokay Cad. Kadikoy
Istanbul
(Turkey)