Diabetes Epidemic in Malaysia
07 January 2007
Second National Health and Morbidity Survey - Diabetes
Among Adults Aged 30 Years And Above
Dr. Rugayah Bakri
Public Health Institute
4. Findings and Discussion
Diabetes mellitus is now a major global public health problem. The incidence and prevalence of diabetes are escalating especially developing and newly industrialized nations. The estimated number of 80 million sufferers in 1990 is expected to double by the year 2000. In Asia alone, it is estimated that the total number of diabetes could reach more than 138 million.
World Health Organization (WHO) recognizes 2 major clinical forms, namely Insulin-Dependent Diabetes Mellitus (IDDM) and Non-Insulin-Dependent Diabetes Mellitus (NIDDM). About 90% of all cases of diabetes in developed and developing countries are NIDDM, primarily found in adults more than 30 years of age. The category of Impaired Glucose Tolerance (IGT) includes those whose glucose tolerance test is beyond the boundaries of normality as defined by 1985 WHO Study Group. When tested 5 to 10 years after diagnosis of IGT, about one-third progresses to diabetes.
The prevalence of diabetes in adults ranges from less than 2% in Tanzania and Mainland China to 40-50% in urban Papua New Guinea. Exceptionally high prevalence is seen in population who have changed from traditional to modern lifestyle. This difference in rates reflects the underlying behavioral environmental and social factors such as diet, level of obesity and physical activity. The lowest rates are often found in rural areas within the country of origin where people live closer to their traditional lifestyles Migrant populations, however, for example the Asian Indians who migrated to various part of the world recorded high prevalence of diabetes.
The prevalence of diabetes is noted to vary with ethnicity. However, the developing and newly industrialized nations, and the disadvantaged community groups in the developed countries are said to be at highest risk of having diabetes. It has also been demonstrated that as age increases, the risk of having diabetes and hence the prevalence of diabetes increases.
About half of the diabetes is unaware of their diabetic condition. This leads to the question of the potential benefits of screening asymptomatic individuals. Symptoms of NIDDM include frequent micturition, unusual thirst, extreme hunger, unusual weight loss, fatigue and irritability. Additional symptoms include frequent infections, blurred visions, wounds that are slow to heal, tingling/numbness in hands or feet and recurrent gum, skin or bladder infections.
The complications associated with diabetes are appalling. It is estimated that about 15,000 to 39,000 people lose their sight because of diabetes and about 14.6% of NIDDM aged 40 years and above, developed diabetic retinopathy after 5 years duration of diabetic condition. It is also estimated that 10% of diabetes develop kidney disease and 50% develop evidence of nerve damage after over 25 years of having diabetes. People with diabetes are 2 to 4 times more likely to have heart disease and 5 times likely to suffer a stroke. The risk of leg amputation is 27.7 times greater and the occurrence of impotence due to diabetes neuropathy, among men is one third of male diabetics. It should be stressed that early detection in asymptomatic individuals provides an opportunity in attempting to prevent or delay the complication of diabetes through dieting and pharmacological measures to achieve euglycaemia.
Hence, it is important that prompt and effective treatment is made available to diabetics. There are 4 major components in the management of diabetes mellitus namely, diet, exercise, medication and education. Nonpharmacologic treatment (diet and exercise) must be attempted for at least 3 months before drug treatment is introduced in ambulant uncomplicated and especially obese diabetics. In addition, monitoring for diabetic control and management of complications should be emphasised.
In Malaysia, diabetes is a growing concern. Through the Ministry of Health's six year thematic Healthy Lifestyle Campaign which began in 1991, diabetes mellitus was the theme for the year 1995. Here, the promotion of adopting healthy lifestyle practices relating to the prevention of diabetes namely creating awareness and balance diet, maintain ideal body weight and physical activities were encouraged. The campaign also emphasised on creating, awareness of the disease and its complications to the public. Guidelines on management of diabetes and patient education to the diabetes were also developed. In addition, many small studies about diabetes had been conducted either on hospital base or selected communities The first National Health and Morbidity survey included diabetes as a major component in the survey This second National Health and Morbidity Survey, attempted to provide a comparative picture of the epidemiology of diabetes in Malaysia within the last 10 years on a wide population based.
2.1 General objective:
To determine the prevalence of diabetes in Malaysia and the health seeking behaviour amongst, the diabetes
2.2. Specific objectives:
2.2.1 To determine, the prevalence of self-reported diabetes by socio-demographic subgroups
2.2.2 To determine the prevalence of undiagnosed diabetes by the socio-demographic subgroups
2.2.3 To describe the health seeking behaviour among the known diabetes in relation to their treatment status, place of treatment, reasons for seeking treatment and presence of complications due to the diabetic condition
2.2.4 To determine the association of other risk factors with the diabetes disease among the known and the undiagnosed diabetes
2.2.5 To formulate recommendations to the Health Programme Managers to strengthen the Diabetic Programme in Malaysia
The details of the sampling design were described in Volume 1. Data on diabetes was obtained from adult respondents 30 years and above through interviews by trained nurses using precoded questionnaires. A 2-hour-post - glucose load test was conducted by the nurses to the respondents who self-professed that they were non-diabetics and have not been diagnosed by any, medical personnel. These non-diabetes were measured for their blood glucose level using glucophotometer in a dry non-wipe technique. Those who refused to be examined were classified as refused to be examined and those who could not tolerate glucose due to old age were classified as unable to be examined.
For the purpose of analysis in this survey, the respondents were categorised into 3 categories. The known diabetes were the adult respondents who self-professed they were diabetics and diagnosed by medical personnel. Those non-diabetics who had undergone the 2 hour - post glucose load test and whose blood glucose measurement level of 11.1 mmol/1 or more were categorised as undiagnosed diabetes. Those with blood glucose measurement of 7.8 - < 11.1 mmol/1 were classified as impaired glucose tolerance (IGT)
The known diabetes were enquired about their treatment status, utilisation pattern of health facilities and perceived complications associated with their diabetic condition.
4. FINDINGS AND DISCUSSION
From the survey, the national prevalence of known diabetes in Malaysia was found to be 5.7% (5.4% - 6.1%). However, through the 2 hour- post- glucose load test, the national prevalence of undiagnosed diabetes was 2.5% (2.3-2. 7%). Taking into account these 2 categories of diabetes, hence the prevalence of diabetes in Malaysia would be 8.3% (7.8% - 8.7%). From other studies conducted in Malaysia, the prevalence seemed to be on the rise. In 1986, the prevalence of diabetes in Peninsular Malaysia as reported in the first National Health and Morbidity Survey was 6.3% and in 1995 as reported by the Cardiovascular Unit in the Department of Public Health, Ministry of Malaysia was 7.7%.
If estimating the population of Malaysia in 1996 to be approximately 21 million, the total number of diabetic sufferers would approximately be 1.7 million. With further industrialisation plus modernisation, the number of people affected by diabetes may double by 2010. By far, Asia was recognised as having the potential increase with 2.5 to 3 times more common diabetes then it is today. Hence, by 2010, Asia was projected to have 138 million diabetic sufferers.
Recently there has been consideration to use the IGT to diabetes ratio as prognostic index of the epidemicity of diabetes in a given population. From this study, it was found that the prevalence of IGT was 4.3% (4.0 - 4,7%). Therefore, the prognostic index here is about 1 ~ 2, possibly implying either the diabetes was on the wane or more likely reflecting a situation in which most genetically susceptible persons already manifested the disease.
Whatever the situation is, the economic implication of diabetes is enormous. In US, it was estimated that with the 7% prevalence of diabetes, it had incurred about US S20.4 billion in 1987 due to direct and indirect costs of diabetes.
The social disease burden and subsequently the economic implication as a result of the diabetic complications is also considerable. Hence, the survey showed that perceived complications associated with their diabetic condition among known diabetes was mainly vision problem (50.6%, 42.2% - 53.9%) and numbness (38.5%, 34.8% - 42.1 %). Similar findings were found in a study conducted by Gafel C. et al that the most common complication was eye disease namely 27% of the diabetic patients. In this survey, another about 10% of the known diabetes perceived that they suffered slow wound healing, stroke and cardiovascular diseases associated with their diabetic condition. Almost similar findings were found by the a hospitalbased study conducted locally in Kuala Lumpur Hospital by the National University Malaysia in 1988.
Diabetic is a costly, disorder. Defining the distribution of specific characteristics among diabetics can assist in the planning, implementing and evaluating diabetic programmes for primary, secondary and tertiary prevention and control of diabetes. In planning of services for diabetes control, equity policies have to be considered.
The survey revealed geographical variations in the observed prevalence of diabetes by states. The highest observed prevalence of known diabetes occurred in the more developed states like Selangor (7.3%, 6.1 - 8.4%) and Penang (7.3%, 5.3 - 9.4%). Similarly, the prevalence of undiagnosed diabetes was highest in the more developed states like Negeri Sembilan (4. 1%, 2.8 - 5.401o), Penang (3, 5%, 2.4 - 4.5%) and Melaka ( 1%, 1.9% - 4.2%). The same findings were found among IGT. States like Melaka (6.6%, 4.6 - 8.6%), Wilayah Persekutuan Kuala Lumpur (5.3%, 3.8-6.9%) and Johor (5.4%, 4.1%-6.7%) recorded highest prevalence of IGT. Similar accounts were observed elsewhere in many literature where urbanisation and modernisation changed the lifestyles of some population which was associated with the increase risk of having, diabetics.
For the 3 categories of diabetes, the urban areas recorded significantly higher prevalence from the rural areas. As many literature documented, the prevalence increased with age for all the 3 categories of diabetes.
By ethnicity, the prevalence of known diabetes in Indians (11.5%, 9.7% - 13.2%) was significantly higher than other races. The Other Bumiputeras recorded significantly low prevalence of the known and undiagnosed diabetes, indicating a true observation of low prevalence among populations whose lifestyles remained close to their traditional lifestyle. Elsewhere, many studies have shown that the migrant Asian Indians had been observed to have a high prevalence of diabetes. Among the IGT, however, the Chinese recorded high prevalence namely 6.5% (5.1% - 7.9%). Since it is said that about one-third of IGT progressed to diabetes, the prevalence in the Chinese would increase in 5 to 10 years time.
From the survey, it was found that the prevalence of all 3 categories of diabetes decreased with education level. The unemployed seemed to have high prevalence of known (12.8%, 11.2% - 14.5%) and undiagnosed (3.6%, 2.8% - 4.5%) diabetes. The pensioners had also high prevalence of known and undiagnosed diabetes varying from 12% in known diabetes to 4% in undiagnosed diabetes. This was probably due to increased prevalence among the older age groups. Although the service sector recorded high prevalence among known diabetes (5.1%, 3.8% - 6.3%) while the sales sectors recorded high prevalence of the undiagnosed (3,30/6, 2.3% - 4.3%), it seemed that there was no significant difference between the working sectors. Similarly, no significant differences were found in gender and income for known and undiagnosed diabetes, Although many prevalence studies showed high prevalence of NIDDM in females than males, analysis on many incidence studies in US by Nelson R.G. and Everhart J. E. showed no evidence of gender influence on risks for NIDDM.
This survey also revealed that 10.7% (10% - 11.9%) of known diabetes had hypertension. In a hospital-based study conducted by Dr. Khalid Kadir in 1988, it was found that 37% of the diabetic patients had hypertension. In another population based study, about 14% of diabetes had hypertension. This survey also showed 21.8% (12.4% - 33.3%) of diabetes had high cholesterolaemia and 7.5% (6.6 - 8.5%) and 11.3% (9.0% - 13.5%) was overweight and obese respectively. These associations seemed to be significant. In organising services for the diabetes, effective and prompt treatment and education must be given to curb, delay or even prevent complications. These will directly increase the quality of life for the diabetics and hence, their productivity.
The current treatment regime especially for obese uncomplicated patients is diet control and exercise which should be attempted for at least 3) months before pharmacologic treatment is started. From the survey, it was found that among the known diabetics on diet control alone comprises 8.5% (6.6% - 10.3%), while those on diet control and currently on medication comprises 71% (68.0 - 74.0%) and those on current medication alone was 6.8% (5.2% - 8.4%). In France, a study in a sample of diabetics from medical analysis laboratories found that 11, 5% of their patients were on diet alone. It was estimated from this survey, that those who were not currently on medication neither were they on diet was 3.5% (2.4% - 4.7%). However, approximately 2% of known diabetes was never on medication while the remainder did not respond or refuse to respond. Conversely, in the first National Health and Morbidity Survey, it was observed that 90.4% were on medication and diet while only 3.8% were on diet alone and only 2.2% was never on medication. Here, the proportion of those on medication alone would have included among those who were on medication and diet together.
The survey revealed that in the less developed states, the proportion of known diabetes on diet alone was high. However, these proportions were not significantly different. The highest proportion was in Kelantan (19.7%, 5.5% - 33.9%) followed by Pahang (18.9%, 8.8% -19.1%) and Terengganu (17%, 6.7% - 29.0%). In Melaka, it seemed none of the known diabetes was on diet control alone. However, Melaka showed a high proportion of known diabetes on diet control and current medication namely 84.6% (75.9 - 93.3%). Similarly, Johor (80.0%, 71.7% - 88.2%), Wilayah Persekutuan Kuala Lumpur (81.1%, 70.2% -92.0%) and Pulau Pinang (79.2%, 67.6% - 90.3%) showed high proportions of known diabetes on current medication and diet.
The survey also showed that Negeri Sembilan (13.7%, 4.4% - 22.9%), P. Pinang (12.3%, 1.6 - 23.1%), Kelantan (11.7%, 1.1% - 22.3%) and Terengganu (11.3%, 0.9% - 21.6%) had high proportions of known diabetes on current medication alone. However, Terengganu (11.5%, 1.9% - 21.2%) showed highest proportions of known diabetes not on current medication and diet.
By strata, the survey showed that urbanites had higher proportions of known diabetes on current medication and diet control (74.0%, 70.2% - 77.8%). Similarly, diet control alone (8.5%, 6.2% - 10.9%) was higher in urbanites. However, higher proportion of diabetics either on current medication alone or neither on current medication or diet were found in the rural areas, (6.5%, 4.8- 7.8% and 5.2%, 3.0% - 7.4 respectively).
By ethnicity, more Malays claimed that they were on diet alone (10.3%, 7.2% - 13.3%) while more Indians (80.6%, 74.4% - 86.1%) claimed they were on diet control and medication. A high proportion of Other Bumiputeras claimed that they were not on current medication or diet control (8.7%, 2.4% - 14.9%).
By gender, there was no significant difference in the proportions in all the categories of treatment status. However, more females claimed they were on medication and diet control (74.0%, 50.1% - 77.9%) while more males claimed they were on diet control alone (9. 1%, 6.3% - 11.9%) and on medication alone (8.2%, 5.7% - 10.3%)
By household income, the proportion of known diabetes on diet control alone decreased with increase in income level while the reverse was observed among those who were on current medication only. Those who were not on diet control or current medication was more on the lower income group. The proportion of those on current medication and diet control increased with the increase in Income level.
The survey showed that the proportion of known diabetes on diet control alone increased with educational level. There was no marked trend observed among those with current medication and diet control.
By age group, there seemed to be a decreasing trend as age increased in the proportions of known diabetes on diet control alone which meant that the younger age group were more on diet control alone. However, the proportions of those on diet and current medication had the reverse trend namely the proportions were higher among the older age groups. This finding corresponded to the findings that those on current medication and diet control were higher among the pensioners while those on diet control alone was higher among the government and private employee (the younger age groups).
Among those who were not on diet control or current medication, the lower income group, the younger age group, the sales sector and employees in the government and private sectors seemed to record higher proportions.
This survey also looked into the pattern of utilisation of health facilities by known diabetes. Statistics collected from government hospitals showed that only 30,000 diabetes patients were hospitalised in government hospitals in 1994 while only about 150,000 were under treatment in government facilities. In this survey it was found that majority of the known diabetes on current medication sought treatment in government facilities namely 56% (52.1% - 59.8%) while only 31.6% (28.0 - 35. 1 %) sought treatment from private facilities. A higher proportion of these diabetes in Melaka (76.1%, 64.3% - 87.9%), Pahang (66.0%, 50.6 - 81.4%) Perak (65.6%, 56.2% - 175. 1 %) and Sarawak (63.8%, 53. 1 % - 74.6%) utilises government facilities. The survey also showed that more of the urbanites (35.6%, 30.9% - 40.3%) used private facilities while more of the rural population (62.2%, 56.1% - 58.2%) used government facilities.
Comparatively, more Chinese (45.9%, 39.1% - 52.8%) used private facilities while more Other Bumiputeras used government facilities (70.7%, 53.2% - 88.3%).
From this survey, it was found that a high proportion of the low-income group utilised more government facilities. On the contrary, a higher proportion of the higher income group utilised private facilities.
The survey also showed that more government employees (57.9%, 55.5% - 80.2%) and housewives (64.3%, 57.7 - 70.9%) used government facilities as compared to private employees. Hence, more private employees used private facilities (51.0%, 42.3% - 63.8%). However, it was observed that the pensioners, government (71.2%, 60.0% - 86.5%) or private (84.2%, 50%, - 118.3%) made up the higher proportions that utilised government facilities
Diabetes is one disease where full co-operation of the patient is necessary to ensure good control. Good adherence by the patients is only when the disease is understood and the objectives of the control is clearly explained.
It was found from this survey that only 7.7% (5.6% - 9.7%) of the known diabetes on current medication ever stopped medication. It was found that the urbanites (7.7%, 5,2% - 10.3%), the males (8.5%, 5.1% - 11.8%), the Malays (10.6%, 6.7% - 14.4%) and the other Bumiputeras (10.9%, 0 - 22.8%), the younger age groups, the higher income groups and the higher educational levels seemed to have higher proportions of medication non-adherence.
When these known diabetes who stopped medication were enquired about their reasons, majority (40.3%) said they felt they had recovered from the illness. About 13.2% said they were advised to stop by their doctor. Here, it probably demonstrated, as suggested elsewhere, that self-perceived health status played an important role in the adherence to diabetic management and metabolic control. Hence, education to patients and family or relatives is pertinent in this context in the control of diabetes.
5.1 Prevalence of diabetes in Malaysia was found to be 8.2%. There was an increase in prevalence as compared to the NHMS in 1986, which only reported 6.3% in Peninsular Malaysia. This indicated that diabetes is a growing concern in Malaysia, which warrants strengthening of the prevention and control programme. It should be noted that the undiagnosed diabetes, which represented the unfelt needs among diabetes, was 2.5%. In addition, the variability of the estimated observed prevalence by states, the urban population having higher prevalence, the increasing prevalence by age and higher prevalence in lower educational level groups requires various emphasis on the allocation of resources provided by, the health care delivery systems. The survey also revealed that the lower income group, the older age groups, and those in the rural areas who utilised more of the government facilities than private facilities. This should be of great concern for health service planners in Malaysia.
5.2. Diabetes is a debilitating disease. Once diagnosed, a diabetic patient must be given prompt and adequate treatment to prevent or delay complications. About 86.3% of the known diabetes was somewhat on medication alone or diet control alone or both medication and diet. It could be seen here that proportion of diabetes on diet alone had increased as compared from the NHMS 1986 which reported 3.8% only. The treatment by diet alone is the treatment being promoted for uncomplicated diabetes especially in obese patients. Hence the health care professionals should realise that education in an effort to gain satisfactory compliance must be emphasised. In the care of diabetes, the health care professionals must spend sufficient time with their patients. Education about diabetes should be extended to relatives and public in order to get full cooperation from patients for their treatment compliance or adherence.
5.3. The survey also revealed significant risks factors were associated with known diabetes, namely 10.9% had hypertension, 22.8% had high hypercholesterolaemia and 18.8% were overweight and obese. Hence it is proposed that as a risk strategy approach be applied in the prevention and control of diabetes in Malaysia where there are resources deficit in the care of diabetes. The findings of this survey showed that the perceived complications namely vision problems and numbness were the commonest among known diabetes. This should be highlighted to consider secondary and tertiary prevention strategies. The timely consensus guidelines recently developed by the Ministry of Health in the management of diabetes retinopathy should be issued to all health facilities either private or government in the attempt to control the most common complication of diabetes.
In the care of diabetes, the socioeconomic implications are alarming. Prevention of diabetes and its consequences would be a major challenge not only in the future, as WHO quoted, but essential in attaining health for all.
Reproduced from The Second National Health and Morbidity Survey II - Diabetes Epidemic in Malaysia was published in 1997 by the Public Health Institute, Ministry of Health, Malaysia