Risk factors for long-term complicationsin patients with type 2 diabetes , in Sri Lanka .

Objective: To identify risk factors for longterm complications in patients with type 2 diabetes in Sri Lanka, Methodology: An unmatched, clinic-based, case control study. Diabetic patients enrolled from randomlyselected medical clinics from primary, secondary and tertiary care level hospitals were interviewed to determine possible risk factors and: screened for longterm complications. 252 diabetic patients having one or more long term complications were selected as cases and 288 diabetic patients free from long term complications included as controls. Results: Peripheral diabetic neuropathy (25.2%), micro albuminuria (22.8%), retinopathy (20%), and coronary heart disease (12.4%) were some complications present among cases. 21.9% had only one complication while 16.5% and 6.9% had two and three complications respectively. Only 1.5% had all four complications. In the univariate analysis, smoking, low family income, body mass index over 25, older age ( over60 years), longer duration of diabetes (11 -15 years), random blood sugar > 11,0mmoV/, raised diastolic bloodpressure > 90mmHg were significantly (p<0.05) associated with the development of long-term complications, The latter four factors were significantly associated with a number of complications. Multivariate analysis identified older age (OR = 5. 51 CI 1.59, 19.17), duration ofdiabetes (OR= 2.08CI 1.23, 3.50), random blood sugar 11.0-16.7 mmol/l (OR= 3.15 CL 1.31, 7.56) and currentsmoking (OR= 8.88, CI 1.53, 51.53) as significant risk factors. ‘4 Management Development & Planning Unit, Dept of Health Services. ? Dept. of Community Medicine, University of Ruhuna. > Dept. of Medicine, University of Sri Jayawardanepura, Journal ofthe College ofCommunity Physicians ofSri Lanka Conclusion: Long-term complications in type 2 diabetes are common amongpatients. Most of jhe significantrisk factors are preventable.


Introduction
Theearly detection and identification of the risk factors contributing to the development of longterm complications in diabetes is an important strategy to minimize the human suffering and costs of the conditions (1). There are several factors related to person characteristics, clinical variables and the delivery ofcare that play an important role in the development of complications (2). Most of these risk factors are considered as avoidable. Poor compliance, uncontrolled diet and lack of knowledge on disease are also associated with an increased risk of development of complications(2). Cigarette smoking is a well-established risk factor for the progression of diabetic complications, where as an association with alcohol consumption is not very clear (1,2). 'Type of diabetes, duration, glycaemic control and uncontrolled hypertension are the strongest clinical predictors of the outcome (3,4).
Diabetes currently afflicts more individuals than some of the communicable diseases in Sri Lanka and it has now emerged as a major public health problem. The National Diabetic Association estimates that there are one million people with diabetes in Sri Lanka (5). Studies done in Sri Lanka have reported that long-term complications are an emerging problem in this country (6,7).
There appear to be challenges in the management of diabetes and its complications in Sri Lanka viz. increasing prevalence, uncertainties in risk factors of diabetes complications in our settings, and limited health care facilities on screening and managementof diabetes complications. Therefore, this study was undertaken to investigate the relationship of long-term complications with some selected risk factors amongstpatients with type 2 diabetes.

Method
This was a clinic based cross sectional study, designed as an unmatchedcase control study. This study was carried out during the period of 1998-1999 in the Western Province of Sri Lanka. Primary, secondary and tertiary level government institutions with diabetic clinic facilities were Volume , 2004 8  A case was defined as a patient attending clinic and diagnosed as type 2 diabetes for a period of 5 years and newly identified with one or more of the following long-term complications during the survey: diabetic retinopathy (by direct ophthalmoscopy after pupillary dilation and the presence of microaneurysms, haemorrhages, cotton wool spots, microvasular abnormalities. Exudates were not considered, because they were not specific for diabetes.) (8); peripheral diabetic neuropathy ( the insensitivity to the 5.07g 'monofilamentat one or more ofnine sites on either foot) (9); diabetic nephropathy ( presence of microalbuminuria, 20 to 200 mg/l, in two consecutive urine collections) (10) Coronary heart diseases ( based on ECG records: coronary probable, coronary possible and normal, according to Minnesota coding system)(11).
Controls were patients attending the diabetic clinic and diagnosed as type 2 diabetes for a period of 5 years, but free from long-term complications at the time of screening, Patients, who were diagnosed as type 2 diabetes, within last five years and were under treatment or treated for the complications or/and risk factors being studied, as well as pregnant women and those who did not cooperate for any reason were excluded. Diabetes, once thought to be a disease of affluent countries, has emerged as a public health concem in the developing countries, including Sri Lanka. The age adjusted (30 -65 years) crude prevalence ofdiabetes for the adult population in Sri Lanka is around 5% (5). In Sri Lanka,patients are able to visit any government health facility they chose. The majority of the study population was female, above the age of 40 years, and from low income groups. This is expected as the majority of working men with diabetes are likely to receive their diabetes care privately.

Journal ofthe College ofCommunity PhysiciansofSri Lanka
Thus the findings ofthis study are generalisable to the patients receiving care in governmentclinics, but may notapplyto those receiving private care 'This wasoneofthelimitations in the presentstudy.

Person related risk factors
Asreported i nearlier studies in many parts of the world, this study also identified that persons of older age over 60 years and low income groups are at higher risk for the development of long-term complications(2, 13). Increased risk ofdeveloping long-term complications at an older age is inevitable, because early onset of diabetes leads to a longer duration of the illness. Even after controlling for these confoundingeffects, age was a highly significant risk factor in developing longterm complications in type 2 diabetes and therefore the importance of continuous treatment should be highlighted in the management of long-term complications (6,13,14).
Effects of smoking on diabetes and long-term complications are well known andestablished (1, 2), This study too revealed similar findings. It was interesting to note, that heavy smokers had a relatively lower risk than average smokers. The possible reason is survival of average smokers than the heavy smokers. In this study, the inverse association between alcohol consumption and longterm complications was established. Orchard et al described,that there was no evidenceof long-term alcohol intake and dose responserelationship in developing long-term complications. In fact they revealed an inverse relationship between alcohol and glycaemia (13). Both smoking and alcoholare predominantly seen in males in Sri Lanka. In this study females accounted for 80% of the study population. As only a small numberof males were included, the results should be interpreted with caution.

Volume , 2004 10
Clinical riskfactors Duration of diabetes, poor GC, raised BP, high level of cholesterol and BMI are established risk factors for complications of diabetes (2, 4, 6, 13). This study also revealed similar findings except in cholesterol: two fold increased risk with long duration of diabetes (11-15 years) and higher RBS over 11.0 mmol/l and, BMIover25. Also all these were statistically significant (p<0.01). Although, the patients with recorded high systolic (>160 mm Hg)and high diastolic (290 mm Hg)blood pressure were found to be at higher risk of developing long-term complications, it was observed that only raised diastolic blood pressure was significant, as a risk factor for diabetic complications, Other studies have reported possible risk of cither one orboth systolic and diastolic blood pressure in complications of diabetes (4,15,16).
However interestingly, longer duration of diabetes (over 20 years), very high level of RBS (>16.7mmol/l), raised cholesterol (>6.2mmol/)) and high BMI (>27) showed a decreasing trendofrisk in the present study, which is contrary to the findings of the studies carried out in other countries (3,13). Theobserved lower risk of complications in those with longer duration of diabetes, very high level of RBS is probably a function of a relative survival, Thetwo major limitations in this study were: (i) non-use of more advance techniques to screen some diabetic complications (HbAs for glycaemic control and Neurothesiometer to detect diabetic neuropathy), these may cause some misclassification of disease status (ii) risk factors were studied for all complications together, but not separately for each complication, Using more advanced techniques in screening and studying a large sample for each complication would have heen ideal, but could not be carried out due to practical and other logistic constraints, In conclusion, ourfindings suggestthat longterm complications in type 2 diabetes are important health problems among patients attending state sector clinics in Sri Lanka. Most of the identified risk factors are preventable. It is obvious with the increase of incidence and prevalence of diabetes, longterm complications of diabetes will tend to rise. Hence, strategy will be plan and implement 'risk factors' oriented preventive Journal ofthe College of Community Physicians ofSri Lanka programmes. Widespread coverage of basic investigation facilities and centres of excellence with advanced techniques for diagnosis of longterm complications should also be established. Further studies are needed in the field of epidemiology of long-term complications of diabetes.