The study included 1,032 patients (mean age, 12.5±4.1 years; 50.5% females, 49.5% males; 67.9% pubertal, 32.1% prepubertal), who were followed with a diagnosis of T1DM for a mean period of 4.7±3.2 years. The majority of the patients (70.4%) were aged between 10 and 20 years. The distribution of the patients according to age groups at the time of evaluation and at the time of diagnosis is presented in .
Distribution of the patients by age groups at the time ofevaluation and at the time of diagnosis
Obesity was present in 4.4% (n=38) of the patients. No statistically significant difference was found between the obese and non-obese T1DM patients in terms of age, diabetes duration and mean HbA1c levels of the past year (p>0.05) ().
Age, duration of diabetes, and hemoglobin A1c (HbA1c)levels in obese and non-obese type 1 diabetic patients
Height SDS was below -2SD in 5% of the patients.Within the past one year, measurement of HbA1c as an indicator of metabolic control was performed three times in 35.5%, four times in 35.8%, twice in 18.4%, only once in 5.5% and more than four times in 4.8% the patients. According to these measurements, 31.6% the patients had good metabolic control, 33.6% had moderate metabolic control, and 34.8% had poor metabolic control. Mean HbA1c level was 8.5±1.8% at the last control visit and 8.4±1.6% in the past year. Mean age and mean duration of diabetes were shorter in Group 1 than in Groups 2 and 3 (). Moreover, it was found that the pubertal patients had significantly higher mean HbA1c levels in the past year as compared to the prepubertal patients (8.6±1.6 vs. 8.2±1.4, p=0.001).
Age and diabetes duration of the patients according to theirmean hemoglobin A1c (HbA1c) levels
Of the patients, 79.5% (694/873=67%) were on flexible insulin therapy (3 or more very fast-acting insulin analogues before meals + long-acting insulin), 5.9% were on insulin infusion (II) pump [continuous subcutaneous II (CSII)], and 3.2% were receiving multiple insulin therapy (NPH+ regular insulin before meals 3 times a day). Thirty (58.8%) of 51 patients using II pump had good metabolic control, whereas 12 (23.5%) had moderate metabolic control. Of the 694 patients receiving flexible insulin therapy, 206 (29.6%) had good metabolic control and 236 (34.0%) had moderate metabolic control. Insulin therapy regimens of the patients and their mean HbA1c levels in the past year are presented in .
Insulin therapy regimens of the patients according to their mean hemoglobin A1c (HbA1c) levels in the past year
Concomitant Autoimmune Diseases
Chronic lymphocytic thyroiditis was identified in 12% patients and Graves’ disease in 0.1%. While 954 (93.3%) of all patients were euthyroid, subclinical hypothyroidism was found in 29 (2.8%) patients, hypothyroidism in 37 (3.6%), and hyperthyroidism in 2 (0.2%) patients at the time of diagnosis or during follow-up.
Of the patients, 4.3% were under follow-up with a diagnosis of GSE. GSE was diagnosed by antibody positivity alone in 16.7% of the patients, by biopsy alone in 5.6%, and by both antibody positivity and biopsy in 77.8% of the patients.
During the past year, severe hypoglycemia and ketoacidosis episodes were observed in 4.9% and 5.2% of the patients, respectively. No significant difference was found among the groups with good, moderate, and poor metabolic control in terms of the number of severe hypoglycemia episodes within the past year (p=0.58), while the number of ketoacidosis episodes was significantly lower in the group with good metabolic control as compared to groups with moderate and poor metabolic control (p=0.007 and p=0.008, respectively). There was no significant difference between the groups with moderate and poor metabolic control in terms of frequency of ketoacidosis (p=0.91; ).
Mean numbers of severe hypoglycemia and ketoacidosis episodesaccording to glycemic control
Mean total cholesterol, HDL- and LDL-cholesterol levels were 162.5±38.8 mg/dL, 57.1±14.4 mg/dL, and 88.2±28.8 mg/dL in the total group. These values were 166.76±39.21 mg/dL, 58.7±14.01 mg/dL, and 90.5±29.0 mg/dL in the boys; 158.14±37.9 mg/dL, 55.5±14.7 mg/dL, and 86.0±28.4 mg/dL in the girls. There was no significant difference between the genders. The rate of dyslipidemia was 17.5%, and 8.2% (n=14) of these patients were obese. The majority of patients with dyslipidemia (75.2%) were pubertal. Patients with dyslipidemia were found to be older compared to the cases without dyslipidemia (13.2±3.9 years vs. 12.4±4.1 years, p=0.02). No significant difference was determined between the patients with and without dyslipidemia in terms of diabetes duration (5.2±3.2 years and 4.7±3.2 years, respectively; p=0.91). However, there was a significant difference between the patients with and without dyslipidemia in terms of the mean HbA1c level in the past year (9.5±2.0% and 8.2±1.4%, respectively; p<0.001).
Focal neuropathy, sensory-motor neuropathy, and polyneuropathy were identified in 1.1%, 1.1%, and 0.5% of the patients, respectively. The patients with neuropathy were significantly older compared to those without (15.8±3.9 years and 12.4±4.1 years, respectively; p=0.001). Mean diabetes duration was significantly higher in patients with neuropathy than in those without (8.3±4.4 years and 4.6±3.1 years, respectively; p=0.00). There was no significant difference between these two groups in terms of mean HbA1c levels in the past year (8.5±1.4% in those with neuropathy and 8.4±1.6% in those without neuropathy; p=0.7).
Retinopathy was identified in 1.4% of the patients. Among them, 64.3% had microaneurysms, 14.3% hard and soft exudates, and 21.4% had proliferative retinopathy. Cataract was observed in 9.5% of the patients. The patients with retinopathy were significantly older than those without (16.7±3.9 years and 12.5±4.1 years, respectively; p=0.001). Mean diabetes duration of patients with retinopathy was also significantly longer than that of those without retinopathy (9.8±5.3 years and 4.7±3.2 years, respectively; p=0.00). There was no significant difference between these two groups regarding mean HbA1c levels in the past year (8.8±1.3% in those with retinopathy and 8.4±1.6% in those without retinopathy, p=0.3).
Diabetic nephropathy was not present in any of the patients, whereas persistent microalbuminuria was noted in 5.4%. The age of patients with and without microalbuminuria was 15.6±3.0 years and 12.4±4.1 years; the difference was significant (p=0.001). The duration of diabetes was significantly longer in patients with microalbuminuria compared to those without microalbuminuria (7.2±3.9 years and 4.6±3.1 years, respectively; p=0.001). No significant difference regarding glycemic control in the past year (HbA1c, 8.8±1.4% and 8.4±1.6%, respectively; p=0.05) was noted.
When the complications were evaluated according to the pubertal stages, nephropathy was present in 7.4% of pubertal patients and in 0.9% of prepubertal patients (p=0.001); retinopathy was present in 1.9% of pubertal patients and in 0.3% of prepubertal patients (p=0.07); neuropathy was present in 3.5% of pubertal cases and in 0.9% of prepubertal cases (p=0.02).