Characteristics of randomized controlled trials on the effectiveness of SMBG in patients with type 2 diabetes who are not using insulin
Study | Intervention | Patients (n) | Duration of study | Baseline characteristics (mean ± SD) | Outcomes (mean ± SD) | Changes between baseline and outcomes (mean ± SD) | Comments |
---|---|---|---|---|---|---|---|
Fontbonne (14), 1989, France | SMBG: measurements twice every other day. SMUG: measurements twice every other day. Control: regular HbA1c determinations every 2 months at physician, no self-monitoring | SMBG 68, SMUG 72, control 68 | 6 months | SMBG: HbA1c 8.2 ± 2.5%, BMI 27.1 ± 4.1 kg/m2, age 54.5 ± 10.7 years, diabetes duration 12.2 ± 6.6 years; SMUG: HbA1c 8.6 ± 2.5%, BMI 26.0 ± 3.4 kg/m2, age 54.9 ± 10.2 years, diabetes duration 13.3 ± 6.8 years; control: HbA1c 8.2 ± 2.5%, BMI 27.0 ± 4.1 kg/m2, age 56.3 ± 9.1 years, diabetes duration 12.7 ± 0.8 years | SMBG: HbA1c 7.84%; SMUG: HbA1c 8.47%; control: HbA1c 7.7% | SMBG: HbA1c −0.36 ± 3.14%; SMUG: HbA1c −0.13 ± 2.20%; control: HbA1c −0.5 ± 1.54% | Withdrawals: 44 patients (21%) lost to follow-up (SMBG 12, SMUG 18, control 14). Compliance: expected number to be used = 182 (SMBG 91 strips, SMUG 79 strips, P < 0.01, poor compliance) |
Allen (30), 1990, U.S. | SMBG: at least 36 blood glucose determinations/ month, before each meal every other day. SMUG: at least 36 urine glucose determinations/month, before each meal every other day. Both groups: standardized treatment program including diet and exercise counseling. Use of an algorithm for treatment alterations by physician | SMBG 27, SMUG 27 | 6 months | SMBG: HbA1c 12.4 ± 3.3%, FPG 12.0 ± 2.4 mmol/l, age 58.2 ± 9.7 years, diabetes duration 6.8 ± 6.5 years; SMUG, HbA1c 11.7 ± 3.0%, FPG 12.0 ± 2.6 mmol/l, age 57.9 ± 10.7 years, diabetes duration 9.0 ± 10.3 years | SMBG: HbA1c 10.4 ± 2.9%, FPG 10.6 ± 3.6 mmol/l; SMUG: HbA1c 9.7 ± 2.6%, FPG 10.5 ± 3.0 mmol/l | SMBG: HbA1c −2.0 ± 3.4%, FPG −1.4 ± 3.2 mmol/l; SMUG: HbA1c −2.0 ± 2.4%, FPG −1.5 ± 2.8 mmol/l | Withdrawals: 7 patients. Compliance: records complete in 87% of visits for SMBG and in 90% of visits for SMUG. Attendance at monthly visits: 98% in both groups |
Muchmore (29), 1994, U.S. | SMBG: individual and group teaching on carbohydrate counting and SMBG, measured six times daily for 4 weeks. Reduce to pre- and postprandial testing of a single meal per day for weeks 4–20. Beyond week 20, individual’s election. Control: identical amount of attention, focus on general principles of diabetes nutrition | SMBG 12, control 11 | 28 weeks and follow-up until 44 weeks | SMBG: HbA1c 10.29 ± 1.1%, BMI 35.1 ± 4.8 kg/m2, age 57.3 ± 8.0 years, diabetes duration 5.7 ± 4.8 years, quality of life* satisfaction 3.1, impact 4, worry-diabetes related 4, worry-social/ vocational related 4.6; control: HbA1c 10.45 ± 1.5%, BMI 33.3 ± 4.3 kg/m2, age 60.1 ± 7.3 years, diabetes duration 5.2 ± 4.6 years, quality of life* satisfaction 3, impact 3.9, worry-diabetes related 4.1, worry-social/vocational related 4.3 | SMBG: HbA1c 8.75 ± 1.66%, quality of life* satisfaction 2.7, impact 4.1, worry-diabetes related 4.6, worry-social/vocational related 4.6; control: HbA1c 9.6 ± 2.09%, quality of life* satisfaction 2.7, impact 3.9, worry-diabetes related 4.5, worry-social/vocational related 4.6 | SMBG: HbA1c −1.54 ± 1.46%, quality of life satisfaction −0.4, impact +0.1, worry-diabetes related +0.6, worry-social/ vocational related ±0; control: HbA1c −0.85 ± 1.87%, quality of life satisfaction −0.3, impact ±0, worry-diabetes related +0.4, worry-social/vocational related +0.3 | Withdrawals: 6 patients of 29 recruited dropped out prior to or at the time of randomization. Compliance: data ascertainment for HbA1c was 96% complete. One control group individual did not complete group meetings. High compliance with carbohydrate counting. Average performance of testing blood glucose (4.67 times per week) |
Schwedes (31), 2002, multicenter study in Germany and Austria | SMBG: measurements of blood glucose six times on 2 days per week and recordings of values obtained in a diary for blood glucose data and documentation of eating habits and state of well-being. Patients were seen every 4 weeks for counseling on use of the meter and regarding diet and lifestyle. Continual use of the glucose meter during the follow-up period. Control: nonstandardized counseling with a focus on diet and lifestyle | SMBG 113, control 110 | 6 months and 6 months of follow-up | SMBG: HbA1c 8.47 ± 0.86%, BMI 31.0 ± 4.6 kg/m2, age 58.7 ± 7.6 years, diabetes duration 5.5 ± 4.8 years, quality of life† general well-being 26.4 ± 5.4, satisfaction 27.6 ± 7.1; control: HbA1c 8.35 ± 0.75%, BMI 31.9 ± 5.5 kg/m2, age 60.5 ± 6.6 years, diabetes duration 5.2 ± 3.9 years, quality of life† general well-being 26.5 ± 5.9, satisfaction 27.0 ± 6.6 | SMBG: HbA1c 7.47 ± 1.27%, quality of life† general well-being 30.4, satisfaction 31.12; control: HbA1c 7.81 ± 1.52%, quality of life† general well-being 28.5, satisfaction 30.6 | SMBG: HbA1c −1.0 ± 1.08%‡, quality of life general well-being +4.0, satisfaction +3.52; control: HbA1c −0.54 ± 1.41%, quality of life general well-being +2.0, satisfaction +3.6 | Withdrawals: 27 patients. Compliance: average number of weekly measurements 24.8 ± 3.9 per patient. Blood glucose/eating diary regularly used by 97.9% of the patients. During follow-up, 87% of the patients continued self-monitoring |
Guerci (32), 2003, France | SMBG: SMBG in addition to the conventional laboratory work-up. Education on weight loss and physical activity; treatment alterations by physician. Measurements at least six times per week, on 3 different days, including weekends. Control: conventional laboratory work-up based solely on laboratory measurement of HbA1c every 12 weeks. Education on weight loss and physical activity; treatment alterations by physician | SMBG 345, control 344 | 24 weeks | SMBG: HbA1c 9.0 ± 1.3%, FPG 7.2 ± 5.1 mmol/l, BMI 30.4 ± 6.1 kg/m2, age 60.9 ± 9.4 years, diabetes duration 7.7 ± 6.3 years; control: HbA1c 8.9 ± 1.3%, FPG 7.5 ± 4.8 mmol/l, BMI 29.7 ± 4.8 kg/m2, age 62.2 ± 9.1 years, diabetes duration 8.4 ± 6.6 years | SMBG: HbA1c 8.1 ± 1.6%, FPG 6.66 ± 4.8 mmol/l, hypoglycemia 53 episodes‡; control: HbA1c 8.4 ± 1.4%, FPG 6.9 ± 4.6 mmol/l, hypoglycemia 25 episodes | SMBG: HbA1c −0.9 ± 1.54%‡, FPG −0.54 mmol/l; control: HbA1c −0.5 ± 1.54%, FPG −0.6 mmol/l | Dropouts: SMBG 164 patients (48%), control 139 patients (40%). Compliance: not clear |
Davidson (33), in press, U.S. | SMBG: before and between 1 and 2 h after eating meals 6 days a week; two breakfasts, two lunches, and two suppers. Recordings of what was eaten. Control: regular HbA1c determinations every 2 months at physician, no self-monitoring. Both groups: five visits to dietician for education on nutrition. Support by nurse, unaware of SMBG status, according to detailed algorithms to make therapeutic decisions | SMBG 43, control 45 | 6 months | SMBG: HbA1c 8.38 ± 2.12%, BMI 31.7 ± 6.7 kg/m2, age 49.8 ± 11.2 years, diabetes duration 5.5 ± 4.7 years; control: HbA1c 8.5 ± 2.2%, BMI 33.4 ± 7.0 kg/m2, age 50.9 ± 11.0 years, diabetes duration 5.8 ± 5.8 years | SMBG: HbA1c 7.53 ± 1.55%; control: HbA1c 7.88 ± 1.5% | SMBG: HbA1c −0.8 ± 1.6%; control: HbA1c −0.6 ± 2.1% | Compliance: dietary visits: SMBG 4.0 ± 1.0, control 3.2 ± 0.9. SMBG averaged 129 of 288 readings (45%) |
↵* Quality of life measured by the diabetes quality-of-life inventory used by the Diabetes Control and Complications Trial with a range of 0 (worst) to 5 (best score) (45).
↵† Quality of life measured by the Patient Well-being Questionnaire, which has a four-item scale with a range of 0 (worst score) to 36 (best score) (21), and the Diabetes Treatment Satisfaction Questionnaire, which has a six-item scale with a range from 0 (very dissatisfied) to 36 (very satisfied) (22).
↵‡ Statistically significant difference between groups (P < 0.05). FPG, fasting plasma glucose.