INTRODUCTION  

Lifestyle  factors  are  associated  with chronic  diseases  such  as  hypertension, coronary  heart  disease,  cancer  and diabetes mellitus (DM). Globally, the pre- valence of DM is on the increasing trend (Wild  et  al.  2004).  In  Malaysia,  the  third National Health and Morbidity Surveys in 2006  showed  that  the  prevalence  of  DM for  those  aged  30  years  and  above  was 14.9%  compared  to  8.3%  in  a  similar survey in 1996.

DM  is  more  prevalent  among  the el- derly,  as there  is an  increased  in elderly population.  In Malaysia,  5.2%  of  the populations were elderly in 1970, 6.3% in 2000  and  projected  to 10.0%  in  2020 (Population  Ageing  Trends  in Malaysia 2005).  

DM  is  more common  in the elderly  be- cause  as  a person  grows  older,  the  de- position  of  body  fat  increases.  For  those aged  above  30  years,  postprandial  glu- cose will increase five mg/dL for every 10 years  of  age. The  rate  of  glucose  ab- sorption  and insulin  production  becomes slower  after  meals.  Insulin  resistance increases  because  of  reduction  in body mass  and increase  in body  fat  (Hall  & Zweig 2005).

Glucose  control  is  important,  as  hyper- glycaemia  is  one  of  the  risk  factors  for the  development  of  DM  complications. For those who are 60 to 69 years old, the life expectancy will be reduced by four to five  years,  and  for  those  who  are  more than 70 years old, type 2 DM reduces life expectancy by three years (Hall & Zweig 2005).  Microvascular  diseases  are  the main cause of blindness and 50% of the amputation  cases  not  caused  by  injuries or  accidents  are  due to DM.  Twenty  five percent  of  new  cases  of  haemodialysis are caused by DM. The risk of ischaemic heart  diseases  and  stroke  increased  by two  to  four  times.  Nearly  80%  of  elderly diabetics  die due  to heart  diseases  and other  vascular  diseases  (Roos  &  Samos 2002).

However,  there  are  multiple  issues  in the  management  of  elderly  diabetics  in- cluding  polypharmacy,  lack  of health knowledge and financial problems (Haas 2006).  Furthermore  the diabetes  popula- tion is also associated with geriatric syn- drome  such  as  functional  disabilities, depression,  fall,  urinary  incontinence, pain  and  dementia,  which  occur  due to the  ageing  and  diabetic  complications. These  often  lead to frailty,  loss  of  inde- pendence and low quality of life (Araki & Ito 2009). Therefore, this group of people often  needs  help  from  their  family members.

Good  glucose  control  requires  the commitment and motivation of their fami- lies.  It may  reduce  the  risk  of  diabetes complications  and  ensures  a better quality  life  for  the elderly  (Hall  & Zweig 2005). Lack of social support may lead to the  aggravation  of  geriatric  symptoms such as functional disability, malnutrition, depression  and  cognitive  impairment among  elderly  diabetics  (Araki  & Ito 2009). Higher level of social support has a role for better glucose control (Okura et al.  2009).  Reblin  & Uchino  (2008)  found that  social  and  emotional  support  from others can be protective for the persons’ health  status.  However,  this  finding  was different  from  White  et al.  (2009)  which showed  that  the elderly  who  needed more social support  was associated  with poorer health outcome.

Glucose control is measured by glyco- sylated  haemoglobin  (HbA1c).  For  every 1%  rise  in  HbA1c,  there  is  a 35 mg/dL rise in blood glucose. Red blood cell  will be  replenished  for  every  8  to 12  weeks, making  HbA1c  the  best  method  of  mea- suring glucose control over the long term (Alam et al. 2005).

 The  objective  of  this  study  was  to  de- termine the prevalence of glucose control among  elderly  diabetics  and  its  asso- ciated  factors.  Factors  studied  were grouped  into  socio-demographic,  history of  diseases,  diabetes  knowledge  and family  support.  In  this  study,  HbA1c  of 6.5%  or  less  was  considered  as  good glucose control (CPG DM 2004). 

 MATERIALS AND METHODS

 This cross sectional study was conducted from February until May 2009 in Kulim. It involved  329  elderly  diabetics,  chosen through  stratified  random  sampling  from seven government health clinics in Kulim. Respondents  were chosen based on the proportion  of  the  registered  diabetic  pa- tients in each clinic.  The inclusion criteria were  elderly  diabetics  aged  60  and above,  and  who  had  been  diagnosed with  DM  for  at  least  one  year.  The exclusion  criteria  were  aphasic respondents,  patients  who  were  on haemodialysis and dementia. 

Respondents  were  interviewed  perso- nally by the researcher using a structured questionnaire.  For  diabetes  knowledge assessment,  the  questions  were  based on  the  Diabetes  Knowledge  Test  pre- pared  by  Diabetes  and  Hormone  Center of  the  Pacific.  Evaluation  for  family  support  was  through  a  questionnaire adopted  from  the  Duke-University  of North Carolina Functional Social Support Questionnaire,  with  some  modification made  to  suit  the  Malaysian  community.  The questionnaire was validated and the Cronbach’s  Coefficient  Alpha  for  the scale of DM knowledge was 0.69 and for family  support  was  0.85.  To  determine the  HbA1c  level,  two  ml  of  blood  was collected from each respondent. 

Statistical  Package  of  Social  Science (SPSS) software, version 12.0  was used in  processing  and  analyzing  the  data. The significant level at p < 0.05 and 95% confidence interval (CI) were used in this study.  The  Research  and  Ethics  Com- mittee,  Universiti  Kebangsaan  Malaysia as well as the Ministry of Health (NMRR- 08-1194-1453)  approved  this  study. Written  and  verbal  consent  were  taken from each respondent.

RESULTS 

The  prevalence  of  good  glucose  control in  this  study  was  22.5%.  Three  hundred and  thirty  one  respondents  were  ap- proached  and  329  agreed  to  participate in  this  study.  The  response  rate  of  this study  was  99.4%.  Women  made  up 52.9%  of  the  respondents.  Ethnicity  dis- tributions  were  Malays  58.4%,  Indians 28.6%, Chinese 12.2% and others 0.9%. The  majority  of  the  respondents  was  in the  60  to  69  years  old  age  group (73.9%),      married  (68.7%)  and  attained up to primary education (76.3%).  

The  majority  of  the elderly  were  diag- nosed  as  DM  for  more  than five  years (68.1%).  With  regards  to co-morbidities, 79.6%  had  hypertension,  46.5%  dyslipi- daemia,  23.1%  ischaemic  heart  diseases,  10.9%  cataract  and  retinopathy, 9.1% joint  and  bone  problems and 2.1% history  of  stroke.  Those  who  had  hypertension,  dyslipidaemia,  ischemic  heart diseases  and  stroke  were  grouped  as having  co-morbidities.  Overall,  85.7% had  co-morbidities.  Bivariate  analysis showed  that  age (odds  ratio  2.24,  95% CI:  1.29-3.89)  and  diabetes  duration (odds ratio 1.90, 95% CI: 1.11-3.24) had significant  association  with  glucose  con- trol as shown in Table 1. 

DM  knowledge  covered  aspects  of diabetes  symptom,  dietary  control,  exer- cise,  complications  and  risk  factors. Mean  DM  knowledge  score  of  the  res- pondents  was  16.96+2.25  (maximum score  was  20.0).  Family  support  was assessed  with  regards  to  physical,  emo- tional  and  information  support.  The  ma- jority of the respondents had good family support  in  all  the  three  aspects.    Mean family  support  score  of  the  respondents was  29.55+4.99  (maximum  score  was 40.0). However, there were no significant associations  between  glucose  control and  diabetic  knowledge  (t=0.757,  95% CI:  -3.60-0.75)  and  family  support  (t=- 0.823,  95%  CI:  -1.84-0.75)  as  shown  in Table 2.

 Logistic  regression  was  used  in  multi- variate  analysis  and  results  showed  the factors  that  influenced  the  good  glucose control  were  gender  (Adjusted  preva- lence  odds  ratio,  APOR=1.75,  95% CI:1.02-3.00),  age  (APOR=2.48,  95% CI:1.40-4.39)  and  DM  duration (APOR=2.10,  95%  CI:1.21-3.64)  as stated in Table 3. 

DISCUSSION

 Glucose control is an important aspect of diabetes management, as it is one of the risk  factors  for  diabetic  complications. Furthermore,  it  influences  the  patient’s quality  of  life  and  increases  the  financial burden  of  diabetes  management.  In  this study,  the  prevalence  of  good  glucose control  was  22.5%.  It  showed  that  the majority  of  the  respondents  had  poor glucose  control.  This  finding  was  similar to  previous  studies,  done  in Kulim  and Kelantan  in  Malaysia,  and  Bangkok  in Thailand  which  showed  that  the preva- lence  of  good glucose  control  ranged from  21.7%  to 33.0%  (Shahidan  et al. 2003;  Eid  et  al.  2003;  Ngarmukos  et al. 2006; Howteerakul et al. 2007).  

However,  there  were  a few  differences between  this  study  and  the previous ones.  The  previous  studies  used HbA1c<7.0%,  but  this  study  used HbA1c<6.5%  for  the level  of  good glucose  control  (based  on CPG  DM 2004).  Another  difference  was  that  the present  study  involved  only  elderly diabetics  who  sought  treatment  at the primary  level,  whereas  the previous studies  involved  both  young  and  elderly individuals  at the  tertiary  level  (Eid  et al. 2003; Ngarmukos et al. 2006). 

This  study  showed  that  males  had  two times  the probability  of  having  good  glu- cose  control  compared  to females.  This finding  was  similar  to  that  of  Mercado  & Vargas  (1990)  and according  to them, this  was  probably  due  to  the  fact  that someone  else  prepared  the  food  for  the males,  where  as  females  prepared  it themselves.  Food  preparation  by  some- one else has an association with glucose control  (Epple  et  al.  2003).  Furthermore, males  were  physically  more  active  than females.  Physical  activity  may  reduce blood glucose level (Durak 1996). 

The majority  of  the  respondents  in  this study  were  aged  60 to 69 years  old. However when assessing the association of  age factors  and glucose  control,  it showed  that,  those  who were  70 years old  and  above,  were  twice  as  likely  to have  good  glucose  control  than  those aged 60 to 69 years old. This finding was similar  to several  previous  studies  which found  that  the  older  age  groups  were more likely to have good glucose control (Trief et al. 1998; Eid et al. 2003; Choi & Rankin  2009).  The  older  patients  are likely  to  practice  a  healthy  diet  and comply  with  their  treatment  compared with  younger  patients  (Wahba  &  Chang 2007).  This  study  also  found  that  there was  no  association  between      glucose control  and  other  socio-demographic factors, which was similar to the study by Suhaiza et al. (2004) in a primary health centre in Kelantan. 

Those  who  had  DM  for  five  years  or less,  were  twice  as  likely  to have  good glucose  control  compared  to  those  who had  DM  for  more  than five  years,  which was  similar  to study  by  Herraez  et al. (1999) and Eid et al. (2003).  The longer the  DM  duration,  the  harder  it will  be to control  glucose  level.  This  is  probably due to drug resistance, resulting in higher doses  and more  drugs  used in diabetes treatment  (Benoit  et al.  2005;  Choi  & Rankin 2009). 

The  commonest  co-morbidity  was hypertension,  similar  to  a study  by Niefield  et al.  (2003).  Co-morbidities  are challenges  in the management  of  DM  in the  elderly  (Crandall  2003).  When assessing  the  association  between glucose  control  and  co-morbidities,  this study found that there was no association between  them.  However,  this  finding contradicted  from  the study  by  Crandall (2003)  and  Suh  et al.  (2008)  which showed  that,  good  glucose  control  was more  likely  among  those  who  did  not have  any  co-morbidity  compared  to pa- tients  with  co-morbidities.  The  difference could  be  due  to the small  percentage  of respondents  in  this  study  who  did  not have co-morbidities.

Generally,  the  respondents  in  this  study had  a  good  knowledge  score.  The  mean score  was  16.96+2.25  (maximum  score was  20.00).  When  assessing  the  associ- ation  of  good  glucose  control  and  DM knowledge  score,  this  study  found  that there was no association between glucose control  and  knowledge  score,  which  was similar  to  the  study  by  He  &  Wharrad (2007). Although this present study showed that  the  diabetes  knowledge  among  the respondents  was  good,  other factors such as poor diet adherence and lack of physical activity  are  likely  to  have  influenced  the glucose control (Eid et al. 2003).  

For family support, the mean score was 29.55+4.99 (maximum score was 40.00).  This  finding  showed  that  the respondents  received  good family support.  However,  when  assessing  the association between glucose control and family support, this study found that there was  no association  between  them.  This was in contradiction to the study by Epple et  al.  (2003)  and  Choi  & Rankin  (2009), which found that, there  was a significant association between family support in the nutritional  aspect  and  glucose  control. The  difference  could  be  due to  the different  aspects  of  family  support studied in this recent study, which include physical,  emotional  and  informational support. 

There were a few weaknesses found in this  study.  As  this  was  a  cross  sectional study, the cause and effect could not be established  by  the  factors  studied.  The respondents  did  not  include  elderly  pa- tients  who  sought  treatment  at  private clinics  and  hospitals.  This  will  limit  the generalization  to  all  elderly  diabetics. There was also the likelihood of informa- tion  bias  from  the  respondents  as  they might  not  give  the  true  answer;  either they  have  forgotten  or  refused  to  reveal the truth.

CONCLUSION

 The  prevalence  of  good  glucose  control in  this  study  was  still  low.  Elderly diabetics who were involved in this study are  at  high  risk  of  developing  diabetic complications. It will affect their quality of life  and  increases  financial  burden  in diabetes management. The factors asso- ciated  with  good  glucose  control  were gender,  age  and  duration  of  diabetes. Therefore,  awareness,  exposure  and health  education  on  the  nutritional  as- pects,  diabetes  treatment  and  complica- tions  should  be  emphasized  at  the  early stage of diabetes diagnoses. 

ACKNOWLEDGEMENTS

We  would  like  to  thank  the  Ministry  of Health  Malaysia,  Kedah  State  Health Department,  health  staffs  and respondents  who  were  involved  in  this study.  This  study  was  supported  by  a research  grant  from  the  Faculty  of Medicine,  Universiti  Kebangsaan Malaysia Medical Centre (FF-244-2008).