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Public health and prevention of blindness in
The world is facing an epidemic of diabetes mellitus
Currently, more than 250 million people in the world have dia-
betes and it is predicted that this number will double in a little
over 20 years
[2–3]. The epidemic is not evenly distributed
around the world. While the world-wide prevalence of diabetes
is 3–4%, several countries and regions experience a prevalence
rate of diabetes of well over 10%. This includes some countries
in the Middle East, where in some cases, the prevalence of dia-
betes among middle aged adults exceed 16%
Diabetic retinopathy is a relatively new disease. Before the
discovery of insulin, less than 100 years ago, it was virtually
unknown. Diabetic retinopathy entered the medical literature
towards the middle of the twentieth century as more diabetics
survived long enough to develop the disease. In the latter part
of twentieth century, diabetic eye disease rapidly became an
important cause of blindness. Epidemiological studies have
shown that about 1/3rd of type 2 diabetics and every other
type 1 diabetic patient is likely to develop sight threatening
retinopathy within their life time. Sight threatening retinopa-
thy, i.e. diabetic macular edema and/or proliferative diabetic
retinopathy represents a significant threat to vision, and
requires medical intervention to reduce risk of the vision loss
and blindness
Blindness from diabetes soared in the latter part of the 20th
century. In Sweden, in the 1980s, it was reported that 4.4% of
type 1 and 1.4% of type 2 diabetic patients were legally blind,
with an additional 4.9% and 7.2% respectively with reduced
[6]. These studies may represent a peak in blindness risk
for diabetics. This is before systematic screening and preven-
tive laser treatment was instituted in Scandinavian countries.
From Wisconsin USA, it has been also reported a 10 year inci-
dence of diabetic blindness of about 2% in type 1 and 4–5% in
type 2, with an additional 9% and 24–37% having visual
impairment [7].
Let us take as an example a hypothetical country with 2
million diabetic patients, mostly with type 2 diabetes. About
1/3rd of this group would be expected to develop sight threat-
ening retinopathy within their lifetime, and in the absence of
early diagnosis and optimal treatment, 50% of these are likely
to suffer vision loss. This worst case scenario would indicate
between 3 and 400,000 current diabetic patients having
reduced vision or blindness. If we look at the American epi-
[7], we might expect about 100,000 people to
become legally blind, and 5–700,000 to suffer from milder
visual impairment, whereas the Scandinavian statistics would
predict slightly lower rates. While the actual outcome also
depends on the overall quality of diabetes care, the availability
of ophthalmic care for those with eye symptoms and tertiary
eye care, this gives an idea of the overall scope of the problem.
Such a rate of blindness is not only a tragedy for the individ-
uals involved and a major problem for the health system,
but an economic burden on society, which needs to support
a large number of people who are unable to work because of
reduced vision.
Retinal photocoagulation has proved to be effective in
reducing the risk of vision loss and blindness, particularly in
proliferative diabetic retinopathy (DRS) and also in clinically
significant diabetic macular edema
[8]. Recently, intravitreal
VEGF antibodies have been reported to be a valuable treat-
ment modality for diabetic macular edema
[9,10]. Careful con-
trol of blood pressure, glucose and other metabolic parameters
also plays a significant role in the treatment of diabetic eye
The key to successful photocoagulation in diabetic
retinopathy is the timing of the treatment. Optimally, patients
receive retinal photocoagulation in the early stages of prolifer-
ative diabetic retinopathy or diabetic macular edema. At this
point in time, treatment is much more likely to succeed than
if the retinopathy were to be more advanced. Since patients
have no or minimal symptoms of early sight threatening
retinopathy, the only way to diagnose sight threatening
retinopathy in its early stages, and ensure the optimal timing
of treatment, is to systematically look for this disease through
screening examinations. This approach started in the 1980s,
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International Journal of Diabetes Mellitus
and has enjoyed enormous success [5,11,12]. Diabetic patients
were scheduled for an annual screening for retinopathy, either
through a standard eye examination with dilated pupils by an
ophthalmologist, or through fundus photography, where the
images were read by expert ophthalmologists. In both cases,
those diabetic patients who were diagnosed with sight threat-
ening retinopathy were referred to laser treatment. It was felt
at that time that annual screening examinations were adequate
for the diabetic group and experience has shown that this
approach resulted in an enormous reduction in the prevalence
of diabetic blindness [5]. Reports from the Nordic countries
now indicate the prevalence of blindness, which is considerably
lower than reported in the 1980s. Zoega reported a 0.3% blind-
ness prevalence in diabetic patients in Iceland
[13]. Olafsdottir
et al. reported about the same in a Swedish population
and Jeppesen and Bek report 0.6 and 1.5% prevalence of legal
blindness in a type 1 and 2 diabetic population in Denmark
[15]. Backlund et al. reported a one third reduction in diabetic
blindness with screening in Stockholm
[16], while Henricsson
et al. reported that the yearly incidence of new blindness was
1 per 1000 in a Swedish diabetic population in a public health
screening program
The public health approach, with regular eye screening, has
significantly reduced diabetic blindness in Nordic countries. At
the same time, diabetic eye disease remains a leading cause of
blindness in the 20–60 year age-group, and one of the most
common causes of blindness overall in many countries around
the world, including the United States
Diabetic retinopathy usually develops 5–15 years after the
onset of disease
[19]. In countries where the prevalence of dia-
betes mellitus is rising rapidly, many individuals, relatively
speaking, will have a short duration of diabetes and may not
yet have developed serious retinopathy. The rise in sight
threatening retinopathy and vision loss follows diabetes epi-
demic with a lag time of approximately 10 years. This delay
is a double edged sword. On the one hand, it may lull health
authorities into thinking that the situation is not as bad as
feared, and may thus ignore the need for a public health
approach. On the other hand, the delay provides time to set
up screening services and organize the public health approach,
the better to prevent the onslaught of sight threatening
retinopathy and to make use of the calm before the storm.
The World Health Organization and all major professional
societies in ophthalmology and diabetology recognize that reg-
ular eye screening and preventive laser treatment are essential
to prevent the diabetes epidemic from becoming an enormous
world-wide epidemic of blindness. The WHO recommends that
every diabetic patient be screened for diabetic retinopathy once
a year, and those diagnosed with sight threatening retinopathy
receive the appropriate treatment. This recommendation is
based, in part, on the experience and success of the Nordic
countries, where 30 years of experience has proved the value
of this approach. The success of retinal screening for diabetic
eye disease is proved by experience, and amply reported in
the medical literature [5,13].
Historically, diabetic eye screening started as annual screen-
ing examinations and this has proved to be adequate for the
successful prevention of blindness. However, this ‘‘one size fits
all’’ approach is clearly simplistic
Diabetic patients are at variable risk for the development of
sight threatening retinopathy. This risk is influenced by the
duration and type of diabetes mellitus, blood glucose levels,
blood pressure, the presence of retinopathy and a few other
minor risk factors
[21,22]. These risk factors create a spectrum
of risk, with some individuals at high risk and many at low
risk, including those with a short duration of diabetes mellitus.
It would clearly make more sense to adjust the screening inter-
vals to the risk profile of the individual patient, so that those at
high risk frequently come for screening examinations and
those at low risk less frequently
We have developed a mathematical algorithm, which calcu-
lates the individual risk for sight threatening retinopathy based
on duration of diabetes, hemoglobin A1C levels, blood pres-
sure and presence of retinopathy and recommends an appro-
priate screening interval for each individual
[24]. This
algorithm is available on the internet on and was
tested in a database of diabetic screening for 20 years in
Denmark. With this algorithm, the number of screening visits
for the population could be reduced by more than 50%, whilst
maintaining safety. This is mostly due to less frequent screen-
ing visits for diabetic patients with short duration of diabetes,
as well as those in very good medical control. This use of infor-
mation technology means that for a given amount of medical
resources, twice the number of diabetic patients may be served,
compared with fixed annual examinations. In a country with a
rising diabetes epidemic and relatively many individuals with a
short duration of diabetes, the use of information technology
may be even more important and increase the efficacy of the
public health approach even more.
A public health approach and screening for diabetic
retinopathy is a proven method to dramatically reduce the dia-
betic blindness
[25–26]. This is the only way to prevent the
world-wide diabetes epidemic from becoming an epidemic of
blindness with enormous implications for health and the econ-
omy. Information technology makes screening more effective
and feasible on a global scale.
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2 Editorial
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Einar Stefa
Anna Bryndı
s Einarsdo
University of Iceland, Landspitali University Hospital,
Reykjavik, Iceland
King Saud University, Riyadh, Saudi Arabia
Corresponding author at: Acta Ophthalmologica,
University of Iceland, National University Hospital,
101 Reykjavı
k, Iceland.
Tel.: +354 543 7217 (O), +354 824 5962 (cell);
fax: +354 543 4831.
E-mail address: (E. Stefa
Editorial 3
... Diabetes mellitus is an endocrinological and/or metabolic disorder [8], and the worldwide prevalence and incidence of it has continued to increase dramatically. Currently, more than 250 million people in the world have diabetes and it is predicted that this number will double over 20 years [9]. The disease results in hyperglycemia which may cause multi-organ damage. ...
... The disease results in hyperglycemia which may cause multi-organ damage. The debilitating effects of diabetes mellitus include various organ failures, progressive metabolic complications such as retinopathy, nephropathy, and/or neuropathy [9][10][11]. The main aim for the treatment of type I and type II diabetes is to cure the symptoms related to hyperglycemia [12]. ...
As diabetes is a complex disorder being a major cause of mortality and morbidity in epidemic rates, continuous research has been done on new drug types and administration routes. Up to now, a large number of therapeutic peptides have been produced to treat diabetes including insulin, glucagon-like peptide-1 (GLP-1) and its analogs. The most common route of administration of these antidiabetic peptides is parenteral. Due to several drawbacks associated with this invasive route, delivery of these antidiabetic peptides by the oral route has been a goal of pharmaceutical technology for many decades. Dosage form development should focus on overcoming the limitations facing oral peptides delivery as degradation by proteolytic enzymes and poor absorption in the gastrointestinal tract (GIT). This review focuses on currently developed strategies to improve oral bioavailability of these peptide based drugs; evaluating their advantages and limitations in addition to discussing future perspectives on oral peptides delivery. Depending on the previous reports and papers, the area of nanocarriers systems including polymeric nanoparticles, solid lipid nanoparticles, liposomes and micelles seem to be the most promising strategy that could be applied for successful oral peptides delivery; but still further potential attempts are required to be able to achieve the FDA approved oral antidiabetic peptide delivery system.
... The world is facing an epidemic of diabetes mellitus [5]. Indonesia has the 4th highest rate of diabetes prevalence in the world after India, China, and United States. ...
Full-text available
Diabetes is a major public health problem. For diabetics, diet shows great potential in controlling blood glucose levels by practicing regular eating patterns, either snacking between meals. Then, it’s important to consume foods with a low glycemic index, meanwhile fulfill daily protein and fiber intake. This study aims to identify organoleptic tests, along with analysis of fiber and protein levels from the best organoleptic test results. This type of research was a pre-experimental design on 3 groups velva. Organoleptic tests were performed on 25 trained panelists using purposive sampling. Analysis technique uses kruskall wallis and mann whitney test. Also, laboratory tests for fiber and protein levels. The results of this study are diabetics have a daily calorie requirement of 1,500 kcal. Moreover, 150 kcal is required for one snack, 7.5 g of protein and 2.5 g for fiber is needed. In addition, based on the results of the organoleptic test, the best velva is formulation 3 (KN 03). The average value obtained from 25 panelists is 3.38. The fiber content contained in the formulation 3 velva is 3.19 g/100 g. Meanwhile, the protein content per 100 g is 8.68 g. The conclusion of this study is that diabetics can consume velva at a rate of 1 cup (100 g) with 151.9 kcal calories per snack consumption to meet 10% of their daily fiber and protein needs. The implication of this research is to find the best velva formulation with high fiber and protein levels for diabetics
... Studi epidemiologi telah menunjukkan bahwa sekitar 1/3 dari penderita diabetes tipe 2 dan setiap pasien diabetes tipe 1 lainnya cenderung mengembangkan retinopati yang mengancam penglihatan dalam waktu hidup mereka. Retinopati yang mengancam penglihatan, yaitu edema makula diabetik dan / atau retinopati diabetik proliferatif merupakan ancaman yang signifikan terhadap penglihatan, dan memerlukan intervensi medis untuk mengurangi risiko kehilangan penglihatan dan kebutaan [49]. ...
Full-text available
Peningkatan angka insiden DM tipe 2 diikuti oleh peningkatan kejadian komplikasi. Komplikasi diantaranya fisik, psikologi, sosial dan ekonomi. Komplikasi fisik yang timbul berupa, kerusakan mata, kerusakan ginjal, penyakit jantung, hipertensi, stroke bahkan sampai menyebabkan genggren. Tujuan penelitian ini untuk mengukur besar risiko untuk melihat gejala komplikasi yang dimiliki penderita DM sehingga penderita DM lebih menagtur pola hidup yang sehat sehingga bisa terhindar dari komplikasi yang berkelanjutan. Rancangan penelitian menggunakan rancangan penelitian survey deskriptif yang melihat gambaran risiko komplikasi penderita diabetes Mellitus Di Unit Pelaksana Teknis Daerah (UPTD) Diabetes Center Kota Ternate. Populasi dalam penelitianinia dalah penderita diabetes Melitustipe II yang ada di UPTD Diabetes Center sebesar 1991. Metode penelitian adalah kuantitatif, sedangkan sampel penelitian ini sebesar 95 responden. Teknik penarikan sampel yang digunakan adalah accidental sampling. Hasil yang diperoleh adalah Sekitar 18,9% responden berusia 50-54 tahun, 64,2% berjenis kelamin perempuan, 55,8% memiliki lama menderita dengan kategori durasi pendek, 56,8% responden memiliki riwayat keluarga menderita diabetes mellitus, 68,4% responden memiliki kebiasaan tidak mengontrol kadar glukosa dengan baik, 40% memiliki kadar kolesterol total darah >200 mg/dl, 34,7% mengalami hipertensi sistolik terisolasi, 85,3% responden memiliki lingkar perut tidak normal, kategori IMT gemuk dan obesitas sebesar 56,9%, 100% responden memiliki resiko mengalami komplikasi penyakit jantung dan stroke, 9,5% responden mengalami komplikasi ulkus diabetik, 8,4% memiliki gejala komplikasi ginjal, 43,2% responden memiliki gejala resiko komplikasi retinopati, 26,3% memiliki komplikasi sindrom metabolik. Disarankan bagi penderita diabetes mellitus untuk lebih meningkatkan self manajemen diabetes untuk kendalikan komplikasi dibetes mellitus.
... affects about 9.3% (29 million) of people aged 20 years or older in the United States[2] ...
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Prostate cancer is one of the diseases worldwide that causes cancer-related deaths in men. Metformin is an antidiabetic drug that has been in use for over two decades for the treatment of Type II Diabetes mellitus (DM2). The purpose of this study was to evaluate the anti-proliferative property of metformin hydrochloride on androgen-sensitive, LNCAP and androgen-insensitive, PC-3 human prostate cancer cell lines at different concentrations (μM and mM) using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Metformin hydrochloride displayed a stronger cytotoxicity on the androgen-insensitive PC-3 than on the androgen-sensitive human prostate cancer cell lines. For both cell lines, the antiproliferative activity of metformin hydrochloride was best displayed at 0.1 mM concentration with average cell death percentage of 60% after 120-hour exposure.
Screen printed carbon electrodes (SPCEs) modified by a combination of chitosan, multi walled carbon nanotubes (MWCNTs) and zinc nanoparticles (ZnNPs) were studied for the first time as a suitable candidate for non‐enzymatic insulin determination. In an effort to find the most suitable modification for electrochemical insulin determination, the stability, analytical characteristics, and selectivity were determined. The results confirmed that the ZnNPs/chitosan‐MWCNTs prepared with the Zn deposition time of 45 s displayed the best electrocatalytic activity towards insulin oxidation in a wide linear concentration range (0.5 μM to 5 μM), with low limit of detection and high sensitivity.
The lipophilic character of peptides can be tremendously improved by hydrophobic ion pairing (HIP) with counterions to be efficiently incorporated into lipid-based nanocarriers (NCs). Herein, HIPs of exenatide with the cationic surfactant tetraheptylammonium bromide (THA) and the anionic surfactant sodium docusate (DOC) were formed to increase its lipophilicity. These HIPs were incorporated into lipid based NCs comprising 41% Capmul MCM, 15% Captex 355, 40% Cremophor RH and 4% propylene glycol. Exenatide-THA NCs showed a log D lipophilic phase (LPh)/release medium (RM) of 2.29 and 1.92, whereas the log D LPh/RM of exenatide-DOC was 1.2 and -0.9 in simulated intestinal fluid and Hanks’ balanced salts buffer (HBSS), respectively. No significant hemolytic activity was induced at a concentration of 0.25% (m/v) of both blank and loaded NCs. Exenatide-THA NCs and exenatide-DOC NCs showed a 10-fold and 3-fold enhancement in intestinal apparent membrane permeability compared to free exenatide, respectively. Furthermore, orally administered exenatide-THA and exenatide-DOC NCs in healthy rats resulted in a relative bioavailability of 27.96 ± 5.24% and 16.29 ± 6.63%, respectively, confirming the comparatively higher potential of the cationic surfactant over the anionic surfactant. Findings of this work highlight the potential of the type of counterion used for HIP as key to successful design of lipid-based NCs for oral exenatide delivery.
Asiaticoside (AC) has been known to have anti-oxidative activity, however, the effect of AC on the progression of high glucose-induced hearing loss has not been studied. This study aims to analyze the effect of AC on cochlear hair cells under the treatment of high glucose in vitro and the hearing function in vivo. The results of MTT showed that high glucose decreased the activity of HEI-OC1 cells, but AC increased the activity of HEI-OC1 cells compared with high glucose group. The results of flow cytometry showed that AC decreased the degree of apoptosis induced by high levels of glucose. The results of DCFH-DA staining showed that AC inhibited the ROS production induced by high glucose levels. The results of JC-1 staining showed that AC inhibited the mitochondrial depolarization induced by high glucose levels. Furthermore, AC decreased the threshold, and protected inner and outer hair cells from damage in rats with hearing loss induced by diabetes mellitus. Moreover, AC decreased the activity of MDA, but, increased the activity of SOD, CAT and GSH-Px in vivo. AC also decreased the expression of AGEs, RAGE and NF-κB p65. Collectively, these results suggest that AC protects cochlear hair cells from high glucose-induced injury by increasing anti-oxidative activity and suppressing the AGEs/RAGE/NF-κB pathway.
Full-text available
Mapping type 2 diabetes mellitus in the whole globe is both interesting and striking when looking at the actual number of affected people with type 2 diabetes mellitus. Calculating the number of diabetic patients using the prevalence of this disease and the total number of targeted population of any given community, provides a good estimate of the number of people affected by the disease. More than 50% of the global number of diabetic patients inhabit a specific geographical area. This area is located in the northern tropical zone, involving North Africa, and the southwest, southern, southeast and eastern part of Asia. It could be labeled as a type 2 diabetes mellitus red zone, which has variable human and land geography. The diabetes red zone occupies less than 20% of the total land global surface area, but at the same time, is inhabited by more than 50% of the total human population [1]. Geographically, the type 2 diabetes red zone is variable, ranging from dry desert areas to heavily raining green land. At the same time, it has the lowest level below sea and the highest mountains above sea level. This area is also unique for its wide cultural, social and ethnic variations. This makes the diabetes red zone area a positive research field for both the geographical and cultural impact of the disease. There is enough epidemiological data to support the fact that type 2 diabetes has a different presence in different populations that are reflected by the incidence of the disease and its prevalence. These could be attributed to different risk factors that affect any given population. Ethnicity, family history and ageing are unavoidable factors, all of which contribute to the high diabetes prevalence in certain populations [2]. Lifestyle change in both developed and developing countries, namely globalization, has had an effect on diabetes prevalence, which is associated with high calorie intake, low physical exercise and obesity. Further studies have confirmed the continuous increase in diabetes prevalence in every country, with a variable figure ranging between 1.4% in rural Vietnam [3] and 70% among Pima Indians in United States [4]. WHO studied the rising prevalence of diabetes mellitus and impaired glucose tolerance based on 75 communities in 32 countries [5] and it is time now for further studies that link the global diabetes database to the status of human health, and its burden on world economy. A population based surveys of the type 2 diabetes red zone would give the greatest chance to study the role of different risk factors that has been linked to the raising type 2 diabetes prevalence. There is enough scientific evidence to link urbanization to an increase of type 2 diabetes mellitus, regardless of the country’s financial status. There are many poor developing countries in this red zone that are affected by globalization and have demonstrated an increase in the incidence of this disease. This has been exacerbated by the new global increase of type 2 diabetes mellitus among children, as a result of the high prevalence of obesity and the change in lifestyle in the form of high calorie dietary intake and low physical activity in that age group [6]. The International Diabetes Federation (IDF) has produced a document listing the top 10 countries in terms of number of people with diabetes aged 20–79 years. This shows 5 out of 10 countries to be from the red zone, namely India, China, Japan, Pakistan and Egypt. These five countries contributed to 94.6% of the total number of people with diabetes among the top 10. It is anticipated that by 2025, Bangladesh will join the top 10 countries, replacing Japan. But when looking at the top 10 countries in terms of prevalence of diabetes, eight countries are located in the red zone area, namely Nauru, United Arab Emirates, Saudi Arabia, Bahrain, Kuwait, Oman, Tonga and Egypt. These countries will remain the top in year 2025. Table 1 shows the top 10 countries, according to the number of diabetic patients and the prevalence of diabetes, which compare data from the year 2007 with expected changes in the year 2025. Although India and China are inhabited by the largest number of diabetic patients (80.7 millions) as a result of their large population size, neither country appeared in the top 10 countries when diabetes prevalence was looked at. When looking to the highest prevalence of diabetes mellitus in the top 10 countries, six countries are from the Arab World (i.e., Middle East), but five of them are from the gulf countries, namely the United Arab Emirates, Saudi Arabia, Bahrain, Kuwait, and Oman. Gulf States have a higher prevalence rate than other Middle East countries such as Egypt. This observation provides a strong clue that Arab Ethnicity is at a higher risk of developing type 2 diabetes mellitus and that populations from Gulf States are the highest. It is anticipated that these countries will continue to be among the top 10 countries in the year 2025. Table 1. The top 10 countries for type 2 diabetes mellitus, according to the number and prevalence for people aged between 20 and 79 years in the year 2007 and 2025. 2007 2025 Patients (millions) Prevalence (%) Patients (millions) Prevalence (%) 1 India (40.9) Nauru (30.7) India (69.9) Nauru (32.3) 2 China (39.8) UAE (19.5) China (59.3) UAE (21.9) 3 USA (19.2) Saudi Arabia (16.7) USA (25.4) Saudi Arabia (18.4) 4 Russia (9.6) Bahrain (15.2) Brazil (17.6) Bahrain (17.0) 5 Germany (7.4) Kuwait (14.4) Pakistan (11.5) Kuwait (16.4) 6 Japan (7.0) Oman (13.1) Mexico (10.8) Tonga (15.2) 7 Pakistan (6.9) Tonga (12.9) Russia (10.3) Oman (14.7) 8 Brazil (6.9) Mauritius (11.1) Germany (8.1) Mauritius (13.4) 9 Mexico (6.1) Egypt (11.0) Egypt (7.6) Egypt (13.4) 10 Egypt (4.4) Mexico (10.6) Bangladesh (7.4) Mexico (12.4) Source: Diabetes Atlas Third Edition, International Diabetes Federation (IDF) – 2006. Table options The type 2 diabetes red zone could now be easily divided into two parts: the eastern part, which has the largest number of diabetic patients but with a prevalence rate of less than 10%; and the western part, which has the highest diabetes prevalence (more than 10%) but a smaller number of diabetic patients, due to their small population size. The western part consists of Middle Eastern countries, which are inhabited mainly by Arab Ethnicity. The Republic of Nauru, an Island in the South Pacific, has the highest global prevalence rate of type 2 diabetes, but is only inhabited by 12,000 people with different ethnicities, according to a United Nations estimation. There are numerous global studies that link ethnicity to type 2 diabetes susceptibility, regardless of environmental factors. Studies have proved that even with equal lifestyle changes, the prevalence of type 2 diabetes mellitus differs between people with different ethnicity, regardless of their geographical location. Jenum et al. have demonstrated the high prevalence of diabetes among South Asian women in Norway after adjustment for age, adiposity, physical activity and education that could be explained by ethnicity [7]. Asian Americans and Pacific Islanders have also been found to be significantly more at risk of developing type 2 diabetes than non-Hispanic whites [8]. These scientific clues may mean that the ethnicity of people from the red zone has a special effect on type 2 diabetes etiology. Tan et al. have shown the effect of ethnicity between Chinese, Malay and Indians in Singapore for type 2 diabetes, especially among females [9], which confirms the ethnicity effect within the red zone geographical location. Arabs who could be considered an ethnicity with high frequency for type 2 diabetes have demonstrated the high prevalence in the Middle East, and also as an immigrant to different parts of the world, as shown in different studies [10]. The red zone for type 2 diabetes relates to high prevalence or large population, and warrants more study and a better focus when fighting this disease and its complications globally. This area is also expected to have more than 50% of mortality and morbidity from this disease. Half of the global economic impact of type 2 diabetes is from this area. This geographical area thus needs more attention when considering prevention programs and drugs supply. References [1] US Consensus Bureau – World POPClock Projection. [2] J.P. Boyle, A.A. Honeycutt, K.M. Venkat Narayan, T.J. Hoerger, L.S. Geiss, H. Chen, et al. Projection of diabetes burden through 2050 Diab Care, 24 (2001), pp. 1936–1940 CrossRef | View Record in Scopus | Citing articles (673) [3] Ekoe Jean-Marie. The epidemiology of diabetes mellitus; 2001. [4] E.T. Lee, B.V. Howard, P.J. Savage, L.D. Cowan, R.R. Fabsitz, A.J. Oopik, et al. Diabetes mellitus and impaired glucose tolerance in three American Indian population aged 45–74 years: the strong heart study Diab Care, 18 (5) (1995), pp. 599–610 CrossRef | View Record in Scopus | Citing articles (156) [5] H. King, M. Rewers WHO ad hoc diabetes reporting group: global estimates for prevalence of diabetes and impaired glucose tolerance in adults Diab Care, 16 (1993), pp. 157–177 CrossRef | View Record in Scopus | Citing articles (781) [6] C.B. Ebbeling, D.B. Pawlak, D.S. Ludwig Childhood obesity: public-health crisis, common sense cure Lancet, 360 (9331) (2002), pp. 473–482 Article | PDF (170 K) | View Record in Scopus | Citing articles (1668) [7] A.K. Jenum, I. Holme, S. Graff-Iversen, K.I. Birkeland Ethnicity and sex are strong determinants of diabetes in an urban western society: implications for prevention Diabetologia, 48 (2005), pp. 435–439 CrossRef | View Record in Scopus | Citing articles (84) [8] Jen’nan Ghazal Read, Benjamin Amick, Katharine M. Donato Arab immigrants: a new case for ethnicity and health? Soc Sci Med, 61 (2005), pp. 77–82 Article | PDF (186 K) | View Record in Scopus | Citing articles (51) [9] C.E. Tan, S.C. Emmanuel, B.Y. Tan, E. Jacob Prevalence of diabetes and ethnic differences in cardiovascular risk factors Diab Care, 22 (2) (1999), pp. 241–247 CrossRef | View Record in Scopus | Citing articles (178) [10] L.A. Jaber, M.B. Brown, A. Hammad, S.N. Nowak, Q. Zhu, A. Ghafoor, et al. Epidemiology of diabetes among Arab Americans Diab Care, 26 (2) (2003), pp. 308–313 CrossRef | View Record in Scopus | Citing articles (78)
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Diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) represent the most common causes of vision loss in patients affected by diabetes mellitus. Diabetic retinopathy (DR) needs special attention because of its high public health impact and impact on quality of life of patients. Actually, laser retinal photocoagulation is the standard of care for the treatment of DR. However, laser treatment reduces the risk of moderate visual loss by approximately 50%, without a remarkable vision recovery. Thus, new approaches in the treatment of DR have been taken into account and, more specifically, the therapy employing antivascular endothelial growth factor (anti-VEGF) drugs could play a meaningful role. VEGF is a pluripotent growth factor that functions as an endothelial cell-specific mitogen and vasopermeability factor. Through these mechanisms VEGF plays a critical role in promoting angiogenesis and vascular leakage. A high level of VEGF has been detected in eyes presenting DME and PDR, and thereby VEGF is an attractive candidate as therapeutic target of pharmacological treatment in the management of DR. In the current chapter, the concepts and results of anti-VEGF therapy in the treatment of the DME and PDR are presented.
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Introduction: Screening programmes for diabetic retinopathy follow guidelines that ensure that vision-threatening complications are detected even when the disease progression is fast. This implies that patients with slow disease progression will be recommended examinations more often than needed. Method: On the basis of previously defined individual risk factors, multiple logistic regression was used to develop a model for individualized determination of the screening interval in diabetic retinopathy, while adjusting for the fact that in the data set used to construct the model, the screening interval acted as a time-dependent confounder. The model was tested on 1372 patients screened during year 2000. Results: It was possible to construct a model for calculating the optimal screening interval in low-risk patients in whom the recommended screening interval was longer than 12 months. When the probability of reaching a treatment requiring event was set to 0.5%, none of the patients reached a treatment end-point in a validation of the model, and the screening interval was prolonged on average 2.9 times in patients with type 1 diabetes and 1.2 times in those with type 2 diabetes. The predictive strength of the model depended on the number of variables included. Conclusions: It is possible to construct a model for optimizing the examination interval during screening for diabetic retinopathy in low-risk patients. The model can potentially be improved by identifying unknown or unmeasured confounders and by including knowledge of risk factors before and after the examination on the basis of which the prediction is made.
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Thesis (doctoral)--University of Iceland, 1996. Includes bibliographical references (p. 65-76).
We studied the incidence of blindness and visual impairment in patients who were enrolled in a photographic control- and screening program for diabetic retinopathy. The study cohort consisted of 2133 patients examined between January 1990 and December 1992 and followed until October 1st 1995. The occurrence of blindness (visual acuity ≤ 0.1) and moderate visual impairment (visual acuity 0.2-0.4) was assessed. The Wisconsin scale was used to grade retinopathy. The mean HbA1c value for the last 8 years was used to represent long-term glycaemic control. Average follow-up time was 2.9 years. Seven patients were blind and 24 had visual impairment caused by retinopathy at the entry of the study. Six patients went blind due to retinopathy during the study period, corresponding to an incidence of 1.0 per 1000 person-years (95% confidence interval 0.4-2.1), and 28 became visually impaired, corresponding to an incidence of 4.6 per 1000 person-years (95% confidence interval 3.0–6.6). Multivariate analysis showed a statistically significant association between blindness/visual impairment and old age, long duration of diabetes, and poor glycaemic control. HbA1c values in the highest quartile, i.e ≥ 8.5%, were associated with a 65% increase in risk of blindness/visual impairment (95% confidence interval 14–130%). Retinopathy was the major cause of blindness and visual impairment in patients with diabetes. The study revealed a low incidence of blindness, which is in line with recent reports. Control of hyperglycaemia may be of value for the prevention of visual loss.
Diabet. Med. 28, 2–9 (2011) We are currently facing a global pandemic of obesity and Type 2 diabetes. In some settings, the population prevalence of Type 2 diabetes is 50%, and half of those affected will die from diabetes-related complications. Eight centuries ago, an epidemic of bubonic plague swept across Europe, killing at least half of its victims. We here draw comparisons between these two pandemics, proposing close analogies between the ‘Black Death’ of the 14th century and the modern-day equivalent of Type 2 diabetes. Both diseases can be considered in terms of an aetiological agent, a reservoir, a vector and a predisposing toxic environment; populations can be considered as highly susceptible to the transmissable agents of Type 2 diabetes in the setting of calorie excess, inadequate food labelling, poorly regulated advertising and sedentary lifestyles. As for tackling a pandemic of a contagious microbial pathogen, we believe that breaking the cycle of transmission in the diabetes epidemic must be underpinned by political will and prompt, decisive legislation backed by the medical community. Far from fearing that such measures edge us towards a ‘nanny state’, we believe individuals should expect a responsible government to safeguard them from the toxic milieu that puts them at risk of obesity and its complications, and that communities and populations have the right to have their health protected.
Background Diabetic retinopathy (DR) is a leading cause of vision loss in the working-age population worldwide. Many observational and preclinical studies have implicated vascular endothelial growth factor (VEGF) in the pathogenesis of DR, and recent successes with anti-VEGF therapy for age-related macular degeneration (AMD) have prompted research into the application of anti-VEGF drugs to DR. Here we review the numerous early studies that suggest an important potential role for anti-VEGF agents in the management of diabetic retinopathy. Conclusions For diabetic macular edema, phase II trials of intravitreal pegaptanib and intravitreal ranibizumab have shown short-term benefit in visual acuity. Intravitreal bevacizumab also has been shown to have beneficial short-term effects on both visual acuity and retinal thickness. For proliferative diabetic retinopathy (PDR), early studies suggest that intravitreal bevacizumab temporarily decreases leakage from diabetic neovascular lesions, but this treatment may be associated with tractional retinal detachment (TRD). Furthermore, several studies indicate that bevacizumab is likely to prove a helpful adjunct to diabetic pars plana vitrectomy (PPV) for TRD. Finally, three small series suggest a potential beneficial effect of a single dose of bevacizumab to prevent worsening of DME after cataract surgery. Use of anti-VEGF medications for any of these indications is off-label. Despite promising early reports on the safety of these medications, we eagerly await the results of large, controlled trials to substantiate the safety and efficacy of anti-VEGF drugs for diabetic retinopathy.
Diabetic retinopathy is screened by fundus photography and screening intervals are defined according to general rules to ensure that vision threatening complications are detected even if the progression of the disease is fast. The resulting superfluous examinations of patients with slow disease progression can be reduced by a more exact decision model that allows an adjustment of the screening interval to each patient's individual risk profile. This requires an identification of independent risk factors for reaching treatment end points for diabetic retinopathy. Clinical data from 5365 patients who had undergone 23 324 examinations at the Department of Ophthalmology, Århus University Hospital between Jan 1st 1994 and Dec 31st 2007 were used to identify independent risk factors for progression of treatment requiring retinopathy. The risk of reaching a treatment end point was in both diabetes types independently affected by retinopathy grade and HbA1c. Furthermore, in type 1 diabetic patients the risk of reaching a treatment end point was independently affected by disease duration and by a recommended control interval of less than 3 months, in spite of correction for retinopathy grade and other studied confounders, whereas in type 2 diabetes this risk was affected by increasing age of diagnosis of the disease. Only a subset of known risk factors for development and progression of diabetic retinopathy should be used to construct a decision model for optimizing screening intervals for diabetic retinopathy.