Study population
Baseline data were collected from 25 primary care units in 18 urban communities, in Samutsakhon province, Thailand. Among 13,256 patients, 6,871 had been diagnosed with T2DM. Participants were recruited in routinely scheduled visits during February 2018 to March 2019. Written informed consent was obtained from all participants. All procedures were approved by the Siriraj Institutional Review Board (095/2560 (EC1)). Participants were eligible for inclusion if they had received care and treatment for T2DM at least for 12 months. Pregnant participants and those with gestational diabetes or at their postpartum stage were excluded. Data were collected through face-to-face interviews and a case record form was completed by research coordinators using standardized questionnaires. All primary care units operated under a standard protocol that included guidelines of diabetic treatments according to the American Diabetes Association (ADA)’s recommendations (26) and the Thai clinical practice guideline for diabetes (27), standard anti-diabetic drugs, clinical investigations, and referral system.
Data Collection
Standardized questionnaires comprised demographic data and self-reported comorbidities such as hypertension, dyslipidemia, gout, chronic kidney disease, and a family history of NCDs. Anthropometric information was retrieved from an electronic medical record. Date of diagnosis, behavioral risk factors, and lifestyle (physical activities, smoking and alcohol consumption) were also collected. The recent use of antidiabetic agents, antihypertensive agents, lipid lowering agents and antiplatelet therapies were retrieved from the medical record. Physical activities or exercise were classified into three categories: (1) less than once a week or seldom, (2) once a week, (3) at least 2–3 times a week. Smoking was classified into three categories: (1) never, (2) quit smoking, and (3) current smoking. Alcohol consumption was classified into two categories: (1) yes or drinking and (2) no or never drinking. Body mass index (BMI) was classified as (1) underweight < 18.5 kg/m2, (2) normal 18.5–22.9 kg/m2, (3) overweight 23.0-24.9 kg/m2, (4) obese I 25.0- 29.9 kg/m2, and (5) obese II ≥ 30.0 kg/m2. Waist circumference (WC) was classified as (1) normal (< 90 cm in men and < 80 cm in women) and (2) over. Optimal blood pressure (BP) was defined by systolic blood pressure (SBP) < 140 mmHg and diastolic blood pressure (DBP) < 90 mmHg as defined the American College of Cardiology/American Heart Association Task Force and the American Diabetes Association (11, 28).
Measurements
Laboratory data including fasting blood glucose (FBG), A1C, total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL-C) were retrieved from the medical record within the preceding 9 months. LDL-C was estimated based on the Friedewald formula (29). Plasma uric acid levels, liver functions (aspartate transaminase; AST, and alanine aminotransferase; ALT) and electrolytes (sodium; Na+ and potassium; K+) were determined by a Cobas 6000 clinical chemistry analyzer (Roche Diagnostics, Basel, Switzerland).
Complication Data Collection
Data were collected on complications including cerebrovascular accident, cerebral infarction, ischemic stroke, hemorrhagic stroke, DR, DN, renal insufficiency, and neuropathy. Retinal photography during the year prior to enrollment was retrieved from the medical record. If this had not been performed, subjects were scheduled for retinal screening using a non-mydriatic seven-field stereoscopic retinal photography (KOWA nonmyd 8S, Kowa, Tokyo, Japan) by a trained technical specialist. Results were verified by an ophthalmologist. DR was defined as the presence of at least one microaneurysm, hemorrhage, or evidence of proliferative retinopathy. DR was reported into three categories: (1) normal or no-DR, (2) non-proliferative diabetic retinopathy (NPDR; mild, moderate or severe), and (3) proliferative diabetic retinopathy (PDR). Techniques and standards (30, 31) for diagnosing retinopathy did not change over the period of the study. To assess renal insufficiency, spot morning urine collected at the clinics was sent to the main lab facility, and stored at 4°C until processing. To determine albuminuria, spot morning urine albumin was measured by an immunoturbimetric assay and creatinine using the enzymatic colorimetric method. Then, the urine albumin-to-creatinine ratio (ACR) was calculated. Staging of DN was categorized according to the Kidney Disease Improving Global Outcomes (KDIGO) 2012 guidelines (32, 33): microalbuminuria and macroalbuminuria as well as serum creatinine (Cr), estimated glomerular filtration rate (eGFR). The presence of neurological problems of the feet was evaluated using monofilament (10 ng). Skin and nail characteristics, the presence of foot deformities, and the risk of foot ulcers were evaluated in all participants (34).
Outcome Assessment
QOC (6, 12) comprised TOC and POC. TOC included the ABC indicators of diabetes: A-A1C, B-BP, and C-LDL-C. POC was the receipt of essential diabetes examinations, including the FACE indicators of diabetes: F-Foot exam, A-A1C exam, C-LDL-C exam, and E-eye exam. In addition, aggregates of the QOC measures were generated for TOC (AllABC), POC (AllFACE), and all QOC indicators (a combination of TOC and POC). AllABC represented all three of the treatment goals achieved. AllFACE represented an indicator variable for cases where all four POC were conducted. All7Q represented an indicator variable of whether all seven of the clinical indicators were achieved, including AllABC and AllFACE. Finally, the count variable Num7Q represented the number of TOC and POC outcomes achieved (0, 1, 2, 3, 4, 5, 6 or 7). Participants were considered as satisfactory for achievement of clinical targets if A-A1C ≤ 53 mmol/mol, B-BP ≤ 130/80 mmHg, and C-LDL-C < 2.6 mmol/l. Participants were considered to have satisfactorily met the examination target if they were examined once in the previous 12 months for A1C, cholesterol, feet and eyes. Moreover, all QOC was also compared the effectiveness with previous studies.
Statistical Analyses
Continuous variables were described using means, and standard error of mean (SEM), whereas categorical variables were summarized using counts and percentages. Comparisons between groups were analyzed by independent t-test or Chi-square test, when appropriate. Logistic regression was used to estimate odds ratio (OR) and 95% confidence interval (95% CI) for predictive factors associated with glycemic control. Significant differences were defined as a p-value less than 0.05. Statistical analyses were performed using STATA version 15.0 (Stata Corporation, College Station, TX, USA).