6187Dd01

8/13/2019 6187Dd01

1/4

SCIENTIFIC REPORT

A study of the relation between body mass index and theincidence of age related macular degenerationH A Moeini, H Masoudpour, H Ghanbari. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Br J Ophthalmol2005;89:964966. doi: 10.1136/bjo.2005.066241

Background:Age related macular degeneration (ARMD) isthe most frequent cause of blindness among the elderly.Obesity may be one of the risk factors of ARMD assuggested, yet not proved, by several studies. This studyassesses the relation between body mass index (BMI) and theincidence of ARMDMethods:This case-control study included 50 patients withARMD and 80 subjects who were adjusted for age, sex,cigarette smoking, blood pressure, and diabetes. Dataanalysis was performed by SPSS V9.0 using Students t

andx2

tests.Results:42% of the subjects in the case group and 35% ofthose in the control group were men. Mean age of subjects inthe case and control groups was 69.9 years (6277 years)and 64.08 years (5671 years), respectively. Mean BMImeasured 25.38 (range 2129) and 30.24 (2634) in thecase and control groups, respectively (p.0.05). 12% ofsubjects in the case group were obese, 42% were over-weight, and 14% were lean. 22.5% of subjects in the controlgroup were obese, 45% were overweight, and 7.5% werelean (p.0.05).Conclusion:43% of patients in this study were aged 70 yearsor older, which is similar to other studies. There was nosignificant difference in BMI between the case and controlgroups. Recent studies indicate that obesity is a probable risk

factor for progression of ARMD, but there is no significantrelation with the presence of ARMD. With multifactorialanalysis, the authors could identify no significant relationbetween the presence of ARMD and the studied risk factors.

Age related macular degeneration (ARMD) is a degen-

erative disease of the macula and the leading cause of

blindness and visual impairment among people aged

50 years or over in the United States and other developed

countries throughout the world.120ARMD affects about 2% of

Americans aged 5264 years, and 28% aged 75 years and

older.2 Successful treatment is limited to an unacceptably

small percentage of patients.1 In the past two decades most

studies have therefore concentrated on the identification ofrisk factors associated with the development and/or progres-

sion of ARMD. These studies investigate the effects of

environmental, genetic, and cardiovascular risk factors on

ARMD.3 Given that ARMD induced visual impairment is

essentially an old age affliction, most investigators prefer to

find modifiable factors, so that patients can be advised on

how to prevent the development of ARMD. As probability of a

causal relation, these studies imply that smoking cessation

and interventions to control blood pressure, atherosclerosis,

glucose, dyslipidaemia, and body weight could help lessen

the incidence and/or progression of ARMD.49 Less consis-

tently, it has been proposed that the use of antioxidants

(vitamins C and E) may have some protective role against

ARMD.21 22 Obesity is a common and serious medical problem

throughout the world, which has adverse effects on health

and longevity.2325 Several studies have suggested obesity as a

risk factor conducive to ARMD progression; nevertheless, no

significant difference has been found regarding the effect of

obesity on ARMD.9 26 As most ARMD environmental risk

factors are preventable, and in view of the undesirable effects

of ARMD on the patients working ability and mental health,

identification and modification of other environmental risk

factors may be effective in decreasing the incidence and

controlling the progression of ARMD.

Body mass index (BMI) as a risk factor for ARMD has been

the focus of few studies; hence we examined the association

between BMI as a modifiable risk factor and development of

ARMD.

PATIENTS AND METHODSThis case-control study was conducted on patients presenting

to Feiz Ophthalmology Center in Isfahan, Iran (September

March 2001). Based on findings of similar studies, sample

size was calculated at 50 subjects in the case group, and 80 in

the control group. Patients diagnosed with ARMD by an

ophthalmologist cooperating with the study were included.

Two ophthalmologists confirmed the diagnosis of ARMD

using stereoscopic slit lamp and biomicroscopic examination

with a special contact lens. Control subjects were alsoexamined to rule out retinal changes. The type of ARMD

was determined and entered in data collection forms. The

subjects weight and height were measured by a single

technician using a mounted Secca scale and a calibrated

metre tape. The case and control subjects blood pressure was

also measured and recorded according to the standard

protocol. History of smoking (packs/year), antihypertensive

and/or antidiabetic medication, and duration of hypertension

and/or diabetes were taken and recorded in data collection

forms. Control subjects were selected among normal indivi-

duals and were matched for age, sex, and risk factors. Control

group data were also obtained using data collection forms.

Data analysis was conducted with SPSS V9.0 using Students

t, x2, logistic regression, and correlation tests.

RESULTSA total of 42% of subjects in the case group were male and

58% were female. Table 1 represents a comparison of

demographic characteristics and ARMD risk factors between

the two groups. In this study, there was no significant

difference between the two group regarding history of

smoking and duration of hypertension and/or diabetes.

Mean (SD) of BMI in the case and control groups

measured 25.38 (3.85) and 30.24 (28.55), respectively

Abbreviations: ARMD, age related macular degeneration; BMI, bodymass index

964

www.bjophthalmol.com

group.bmj.comon July 24, 2012 - Published bybjo.bmj.comDownloaded from
http://group.bmj.com/http://group.bmj.com/http://group.bmj.com/http://bjo.bmj.com/http://bjo.bmj.com/http://group.bmj.com/http://bjo.bmj.com/

8/13/2019 6187Dd01

2/4

(p,0.05). Table 2 shows a comparison of BMI in case and

control subjects.

Mean (SD) of height, weight, and BMI measured 157.67

(8.76) cm, 63.20 (11.17) kg, and 25.39 (3.58), respectively,

in the case group, and 154.61 (12.07) cm, 67.03 (17.29) kg,

and 30.24 (28.55), respectively, in the control group

(p,0.05). In this study, mean (SD) of right intraocular

pressure measured 15.24 (3.71) mmHg (10 mmHg

32 mmHg) in the case group and 17.14 (3.33) mmHg

(10 mm Hg28 mm Hg) in the control group (p,0.05); 76%

of subjects in the case group were dry type and 24% were wet

type of ARMD.

Multifactorial analysis showed that neither of the studied

risk factors was a predictor of ARMD development.

DISCUSSIONAge related macular degeneration is the leading cause of

visual impairment in people 50 years or over in developed

countries.120 As gauged by BMI, 42% of the cases in this

study were overweight and 12% were obese. Similarly, 45% of

control subjects were overweight and 22.5% were obese. A

study by Schaumberg et alof 256 cases of dry and 84 cases of

neovascular ARMD showed a significant association between

BMI and development of ARMD; however, risk ratio for

ARMD development measured 1.43, 1.24, and 2.15 for lean,

overweight, and obese individuals, respectively. In this study,

obesity was considered a risk factor for ARMD, yet lean

individuals also seemed to be at risk.26 Mean (SD) of BMI in

the case and control groups in this study measured 25.38(3.85) and 30.24 (2.85), respectively, showing no significant

difference between the two groups.

Given the multifactorial aetiology of ARMD, the main

physiopathology of ARMD was seen less often in patients

with lower BMI, although comparison of BMI did not show a

significant difference between case and control groups.

ARMD patients had more risk factors. Although no sig-

nificant difference was observed, the difference can thus be

explained.

Mean (SD) of right intraocular pressure in the case and

control groups measured 15.24 (3.71) mm Hg and 17.14

(3.33) mm Hg, respectively. Left intraocular pressure in the

case and control groups measured 15.72 (3.64) mm Hg and

17.95 (6.36) mm Hg, respectively, showing a significant

difference between the two groups.

Recent studies of patients with open angle acute glaucoma

have highlighted BMI as an independent and significant risk

factor for increased intraocular blood pressure.25 26 Studies of

the association of BMI and intraocular pressure have yielded

results consistent with these findings.

These findings did not implicate BMI in the development

of ARMD. Mean (SD) of age in the case group was 69.9 (7.32)

years. In similar studies, ARMD patients had a mean age of

66 years, within a range of 4399 years.3

In this study, BMI in the control group was higher than

that in the case group. Other risk factors may have a moreprominent role in the development of ARMD. There are

inconsistent results regarding the protective effect of anti-

oxidants on the incidence of ARMD.21 22 Some studies have

proposed that factors such as age, tobacco smoking, heredity,

sex, high blood pressure and other cardiovascular risk factors,

iris colour, age menopause, hormone replacement therapy,

diet, and oxidative damage may be effective in the develop-

ment and progression of ARMD.39

Nevertheless, opinions are divided and further multicentric

studies are warranted to better understand the role of each of

these factors.

ARMD is known to be of multifactorial aetiology and

obesity does not seem to be directly involved in its

pathophysiology, however, since obesity has been related to

many of the complications associated with old age, prevent-ing it may lessen the effect of other ARMD risk factors.

Authors affiliations. . . . . . . . . . . . . . . . . . . . .

H A Moeini, H Masoudpour, H Ghanbari, Feiz Hospital,Ophthalmology Department, Isfahan University of Medical Sciences,Isfahan, Islamic Republic of Iran

Correspondence to: Dr Hassan Masoudpour, No 12, Jomhori Square,Dr Masoudpour Alley, Isfahan, Islamic Republic of Iran;[email protected]

Accepted for publication 1 February 2005

Table 1 Comparison of demographic factors and ARMD risk factors in the case andcontrol groups

Case (n = 50) Control (n = 80) p Value

SexMale 21 (42%) 28 (35%) NSFemale 29 (58%%) 52 (65%) NS

Mean age (SD) 69.9 (7.32) 64.08 (7.6) NSDiabetes 10 (20%) 13 (16.25%) NSHypertension 23 (46%) 34 (42.5%) NSSmoking 10 (20%) 12 (15%) NS

Mean blood pressureSystole (mm Hg) (SD) 143.3 (31.8) 150.5 (26.4) NSDiastole (mm Hg) (SD) 83.2 (15.1) 84.03 (14.1) NS

NS, not significant.

Table 2 Comparison of body mass index (BMI) in case and control groups

Case n= 50(%)

Control n = 80(%) p Value

Lean BMI ,20 7 (14) 6 (7.5) NSNormal 20( BMI ,25 16 (32) 20 (25) NSOverweight 25( BMI ,30 21 (42) 36 (45) NSObese BMI >30 6 (12) 18 (22.5) NS

NS, not significant.

96 5



8/13/2019 6187Dd01

3/4

REFERENCES1 John RH, Gary WA,et al. Basic and clinical science course section 12 (retina

and vitreous). San Francisco: American Academy of Ophthalmology, 19945.

2 Leibowitz HM, Krueger DE, Maunder LR,et al. The Framingham Eye Studymonograph: an ophthalmological and epidemiological study of cataract,glucoma, diabetic retinopathy, macular degeneration, and visual acuity ingeneral population of 2631 adults, 19731975. Surv Ophthalmol1980;24(Suppl):335610.

3 Smith W, Assink J, Klein R, et al. Risk factors for age-related maculardegeneration. Ophthalmology2001;108:697704.

4 Cooper RL. Blind registrations in western Australia: a five year study.Aust N Z J Ophthalmol1990;18:4216.

5 Ghafour IM, Allan D, Foulds WS. Common causes of blindness and visualhandicap in the west of Scotland.Br J Ophthamol1983;67:20913.

6 Wachter A, Sun Y, Dasch B,et al.Munster age and retina study (MARS):Association between ri sk f actors f or atherosclerosis and age-r elated maculardegeneration. Ophthalmologe2004;101:503.

7 Klein R, Klein BE, Tomany SC,et al.The association of cardiovascular diseasewith the long-term incidence of age-related maculopathy: the Beaver Dam eyestudy.Ophthalmology2003;110:63643.

8 Van Leeuwen R, Ikram MK, Vingerling JR,et al. Blood pressure,atherosclerosis, and the incidence of age-related maculopathy: the RotterdamStudy. Invest Ophthalmol Vis Sci2003;44:37717.

9 Seddon JM, Cote J, Davis N, et al.Progression of age-related maculardegeneration: association with body mass index, waist circumference, andwaist-hip ratio.Arch Ophthalmol2003;121:78592.

10 Seddon JM, Cote J, Rosner B. Progression of age-related maculardegeneration: association with dietary fat, trasunsaturated fat ,nuts, and fishintake. Arch Ophthalmol, 20033,121:172837.

11 Yonoff M, Jay SD.Ophthalmology. St Louis: Mosby, 1999.12 Chan CW, Bilson FA. Visual disability and major causes of blindness in NSW:

study of people aged 50 and over attending the Royal Blind Society 1984 to

1989.Aust N Z J Ophthalmol1991;19:3215.

13 Kahn HA, Moorhead HB.Statistics on blindness in the model reporting area,19691970. Bethesda MD: US Dept of Health, Education, and Welfare, NIH,1973:73427.

14 Klein R, Klein BE, Linton KL,et al.The Beaver Dam Eye Study: the relation ofage-related maculopathy to smoking.Am J Epidemiol1993;137:190200.

15 The Eye Disease Case-Control Study Group. Risk factors for nerovascularage-related macular degeneration.Arch Ophthalmol1992;110:17018.

16 Hyman LG, Lilienfeld Am, Ferris FL 3rd,et al. Senile macular degeneration: acase-control study.Am J Epidemiol1983;118:21327.

17 Paetkau ME, Boyd TA, Grace M,et al.Senile disciform macular degenerationand smoking.Can J Ophthalmol1978;13:6771.

18 Vinding T, Appleyard M, Nyboe J, et al.Risk factor analysis for atrophic andexudative age related macular degeneration. An epidemiological study of1000 aged individuals. Acta Ophthalmol (Copenh)1992;70:6672.

19 Klaver CC, Assink JJ, Vingerling JR,et al.Smoking is also associated with agerelated macular degeneration in persons aged 85 years and older: theRotterdam Study [letter]. Arch Ophthalmol1997;115:945.

20 Van Leeuwen R, Klaver CC, Vingerling JR,et al.Epidemiology of age-relatedmaculopathy: a review.Eur J Epidemiol2003;18:84554.

21 Age-Related Eye Disease Study Research Group. A randomized clinical trialof high-dose supplementation with vitamins C and E, beta carotene, and zincfor age-related macular degeneration and vision loss. Arch Ophthalmol2001;119:141736.

22 Mares-Perlman JA, Klein R, Klein BEK,et al.Association of zinc andantioxidant nutrients with age-related maculopathy.Arch Ophthalmol1993;111:49.

23 Becker KL. Obesity.Principles and practice of endocrinology and metabolism.2nd ed. 1995:11559.

24 Mori K, Nomora H, Sato Y, et al. Relationship between intraocular pressureand obesity in Japan.Int J Epidemiol2000;29:6616.

25 Gasser P, Stompfy D, Schotzau A, et al. Body mass index in glaucoma.J Glaucoma1999;8:811.

26 Schaumberg DA, Christen WG, Hunkinson SE,et al.Body mass index and theincidence of visually significant ARMD in men. Arch Ophthalmol

2001;119:125965.

Call for papers

11th European Forum on Quality Improvement in Health Care2628 April 2006, Prague, Czech RepublicDeadline 30 September 2005.For further information and to submit online go to: www.quality.bmjpg.com

966



8/13/2019 6187Dd01

4/4

doi: 10.1136/bjo.2005.0662412005 89: 964-966Br J Ophthalmol

H A Moeini, H Masoudpour and H Ghanbaridegeneration

macularindex and the incidence of age relatedA study of the relation between body mass

http://bjo.bmj.com/content/89/8/964.full.htmlUpdated information and services can be found at:

These include:

References

http://bjo.bmj.com/content/89/8/964.full.html#related-urlsArticle cited in:

http://bjo.bmj.com/content/89/8/964.full.html#ref-list-1

This article cites 20 articles, 5 of which can be accessed free at:

serviceEmail alerting

box at the top right corner of the online article.Receive free email alerts when new articles cite this article. Sign up in the

CollectionsTopic

(507 articles)Vision

(1061 articles)Neurology(780 articles)Epidemiology

(1238 articles)Retina(389 articles)Public health

Articles on similar topics can be found in the following collections

Notes

http://group.bmj.com/group/rights-licensing/permissionsTo request permissions go to:

http://journals.bmj.com/cgi/reprintformTo order reprints go to:

http://group.bmj.com/subscribe/To subscribe to BMJ go to:

http://bjo.bmj.com/content/89/8/964.full.htmlhttp://bjo.bmj.com/content/89/8/964.full.htmlhttp://bjo.bmj.com/content/89/8/964.full.html#related-urlshttp://bjo.bmj.com/content/89/8/964.full.html#related-urlshttp://bjo.bmj.com/content/89/8/964.full.html#ref-list-1http://bjo.bmj.com/cgi/collection/visionhttp://bjo.bmj.com/cgi/collection/visionhttp://bjo.bmj.com/cgi/collection/visionhttp://bjo.bmj.com/cgi/collection/neurologyhttp://bjo.bmj.com/cgi/collection/neurologyhttp://bjo.bmj.com/cgi/collection/epidemiologyhttp://bjo.bmj.com/cgi/collection/epidemiologyhttp://bjo.bmj.com/cgi/collection/epidemiologyhttp://bjo.bmj.com/cgi/collection/retinahttp://bjo.bmj.com/cgi/collection/public_healthhttp://group.bmj.com/group/rights-licensing/permissionshttp://group.bmj.com/group/rights-licensing/permissionshttp://journals.bmj.com/cgi/reprintformhttp://journals.bmj.com/cgi/reprintformhttp://group.bmj.com/subscribe/http://group.bmj.com/http://group.bmj.com/http://group.bmj.com/http://bjo.bmj.com/http://bjo.bmj.com/http://group.bmj.com/http://bjo.bmj.com/http://group.bmj.com/subscribe/http://journals.bmj.com/cgi/reprintformhttp://group.bmj.com/group/rights-licensing/permissionshttp://bjo.bmj.com/cgi/collection/visionhttp://bjo.bmj.com/cgi/collection/neurologyhttp://bjo.bmj.com/cgi/collection/epidemiologyhttp://bjo.bmj.com/cgi/collection/retinahttp://bjo.bmj.com/cgi/collection/public_healthhttp://bjo.bmj.com/content/89/8/964.full.html#related-urlshttp://bjo.bmj.com/content/89/8/964.full.html#ref-list-1http://bjo.bmj.com/content/89/8/964.full.html

Documents

6187Dd01