Introduction

The elderly population is expected to grow considerably in the near future.¹ This rise will especially be prominent in the developing countries where an increment of 140% is projected, compared to 51% in the developed countries.² As a result of this, a significant impact on the overall healthcare cost is inevitable. According to a study done in nine countries from the Organization for Economic Co-Operation and Development Countries (OECD) in the 1990s, health expenditure of people aged 65 and above ranged from 32% to 42%, which was far beyond their population share of 12% to 18%.³

Cardiovascular diseases especially hypertension and diabetes are a major public health concern especially in older adults. The reported prevalence of hypertension varies between countries and within communities in the same country depending upon the economic development and affluence. Prevalence of hypertension in the Asia-Pacific region ranges from five to 47% in men and from seven to 38% in women.⁴ Based on the National Health and Morbidity Survey (NHMS) III the national prevalence of hypertension in Malaysia in 2006 was 32.2% for residents aged 18 years and above.⁵ Most were unaware that they had hypertension, while those who were aware and on treatment, most did not have controlled blood pressure. The prevalence of hypertension among the elderly in north Malaysia has been reported as high as 58.3% in the community and ranging from 36 to 50.3% in old folks homes.⁶

The prevalence of diabetes mellitus is also increasing in Malaysia over the decades as shown in the First and Second National Health and Morbidity Survey ^7&8. A rise of prevalence from 6.3% to 8.3% was observed in Malaysia between 1986 and 1996. This figure continued to increase tremendously to 14.9% in 2006 as revealed by the Third National Health and Morbidity Survey.⁵

Although hypertension and diabetes mellitus among the elderly are common and could lead to severe cardiovascular complications, local studies in this field are still limited. The objective of this study was to determine the prevalence of hypertension and diabetes and their associated factors amongst the residents of a privately run home for the aged in Penang, Malaysia.

Method

Setting: This study was conducted in a 190-bed non-governmental charity elderly care residential home in Penang, Malaysia. The criteria for admission in this residential home is that an individual should be 60 years old and above, have no children, homeless or lack funds for self care.

Study Design: To achieve the objective of the study, a cross sectional study design was chosen. The study was conducted in May 2010.

Sampling: Participants were taken from amongst the residents of this institution. Only residents who consented and were not debilitated with an illness which rendered them unable to communicate effectively were recruited.

Instruments: The data was collected by trained research assistants using a questionnaire especially designed for this study. Besides the baseline demographic data cognitive impairment was screened using Elderly Cognitive Assessment Questionnaire (ECAQ) and geriatric depression was screened using Geriatric Depression Scale (GDS). In addition, Barthel’s index, a well established and commonly used nursing tool, was used to assess the functional independence in activities of daily living (ADL) of the participants. Body mass index which is commonly used to determine a person’s nutritional status was also calculated.

The procedure used for blood pressure (BP) measurement was based on the American Heart Association guidelines.⁹ Blood pressure was measured in the sitting position using a mercury sphygmomanometer. Diastolic BP was identified by the disappearance of phase V Korotkoff sounds. Blood pressure was measured on three different occasions and a diagnosis of hypertension was made when BP was equal to or above 140 mm Hg systolic or more than 90 mm Hg diastolic or when the participant volunteered history of being on anti-hypertensive medication.

Fasting blood glucose was measured using a capillary glucometer. A drop of capillary blood was obtained from the participant’s finger which was cleaned with alcohol swab beforehand. The blood was placed on the glucometer strip. The glucometer was then turned on to obtain the blood sugar reading. Diabetes mellitus was defined as measured fasting blood glucose equal to or above 7.0mmol/l or having a history of diabetes mellitus. This cut-off point was obtained from American Diabetes Association (ADA) diagnostic criteria.¹⁰

Analysis: Analysis was done using SPSS version 13. Chi square test was used to analyze the relationship between the variables. A “p” value of <0.05 was considered statistically significant. Odds ratio was used to estimate risk of hypertension and diabetes mellitus.

Ethics: The research was conducted ethically. All participants were asked to give an informed consent before starting the interview. The anonymity of the participants was assured. The study had received the approval of the institutional ethics committee before commencing.

Results

There were 190 residents in the residential home, 155 participated giving a response rate of 81.6%. Table 1 shows the demographic profile of the residents. There were 73 male and 82 female participants in this study. Most were in the age group of 70-79 years old, followed by ≥80 years old and 60-69 years old. Majority of them were Chinese, Buddhist, unmarried and literate.

Figure 1

Table 1: Demographic profile of the participants

Hypertension

As shown in Table 2, the mean systolic pressure of the participants was 132.6 mmHg and the mean diastolic pressure was 74.0 mmHg. There was an increasing trend in the mean systolic blood pressure as age increased. The mean blood pressure of races other than Chinese was higher.

Figure 2

Table 2: Mean systolic and diastolic blood pressure

The prevalence of hypertension was 62.6% (97). There were 63 participants with known hypertension and another 34 were newly diagnosed with hypertension. Among the known hypertensive’s, 47.6% (30) had uncontrolled blood pressure as shown in table 3.

Figure 3

Table 3: Prevalence of hypertension among the residents

As shown in table 4, there were more hypertensives among the females, those in the age group of 70-79, illiterates, those dependent on the activities of daily living and the depressed. Diabetics were almost three folds at risk of having hypertension.

Figure 4

Table 4: Factors associated with hypertension

Diabetes Mellitus (DM)

The mean fasting blood glucose of the participants was 6.2 mmol/L. The prevalence of DM was 25.8% (40). A total of 18 participants were known diabetics on medication and 22 were newly diagnosed. Among the known cases of DM, the blood glucose level of 33.3% (6) were poorly controlled.

Figure 5

Table 5 – Prevalence of Diabetes mellitus

The mean fasting blood glucose of those with diabetes mellitus was 6.4 mmol/L. As shown in Table 6, mean fasting glucose was found to be highest in the 70-79 age group. Higher mean fasting blood glucose was found among the females, non-Chinese, non-Buddhists, widows/divorced, illiterates and housewives. Higher fasting blood sugar was also noted among those who were hypertensive and depressed. As shown in table 6, the mean blood glucose of those with DM was 6.4 mmol/L and those without DM 6.3 mmol/L.

Figure 6

Table 6: Mean blood glucose levels

There were more diabetics among those aged 70-79 years old, among widow/divorced, illiterates, housewives, those with hypertension and among those dependent on the activities of daily living. Those with hypertension were almost three folds at risk of being diabetic as seen shown table 7.

Figure 7

Table 7: Prevalence of Diabetes mellitus with its risk factors

Discussion

Prevalence of Hypertension

Prevalence of Diabetes mellitus

Risk of hypertension and diabetes mellitus

Conclusion

This study revealed a high prevalence and low awareness rates of both hypertension and diabetes mellitus among the elderly in this institution. This reflects an essential need for a more vigilant screening program in this vulnerable population.

Limitation

The sample size in this study was much smaller in comparison to other well-established international studies. Furthermore, as the study was conducted in a private institution, which consisted of mainly Chinese, the results might not be representative of a multiracial country like Malaysia. This is clearly demonstrated when the non-Chinese participants were found to have significantly higher fasting blood glucose compared to the Chinese. It was tempting to attribute this to genetic variation and lifestyle differences among races. However, the finding of the association between hypertension and diabetes mellitus is very important.

Secondly, although fasting values for venous and capillary plasma glucose are identical, fasting plasma glucose alone fails to diagnose 33% of cases of previously undiagnosed diabetes.⁴³ This could subsequently lead to an underestimation of the prevalence of diabetes in this study. Unfortunately, a diagnostic oral glucose tolerance test had to be omitted due to limited resources.

Acknowledgement

This study had received a grant from Penang Medical College, Malaysia. We would like thank the Dean of Penang Medical College for approving this study. We are also grateful to the manager and staff of the elderly care institution for their cooperation.