The quality of T2DM care is affected not only by patient characteristics such as age, sex, ethnicity, socioeconomic position, educational status, and lifestyle but also by healthcare system factors such as healthcare organization, insurance system, financial incentives, clinical guidelines, and care-provider characteristics such as age, sex, and specialty [11,12,13,14]. The role of general practice and diabetic clinics in the management of diabetes is still a matter of debate. Studies have consistently shown that specialist care is associated with better process outcomes in type 1 diabetes . For type 2 diabetes, some studies have suggested that patients with diabetes achieve better glycemic control with specialist care than with care by general practitioners [11, 16]. Conversely, some studies, including our previous study [6, 16], have shown that there are no substantial differences between specialists and general practitioners in terms of outcome, although specialists tend to perform better than general practitioners in process measures [11, 17].
From our survey, overall HbA1c levels in patients with T2DM treated by general practitioners were lower than those in patients treated by specialists. In addition, the median HbA1c levels of patients treated by general practitioners in any group that was divided on the basis of patient age and BMI were lower than those of patients treated by specialists. However, multivariable regression analysis showed that lower age, higher BMI, and being female were associated with higher HbA1c levels in this study. Consistent with the findings of our previous study , the HbA1c levels of patients treated by general practitioners were lower than those of patients treated by specialists, regardless of patient age and BMI.
One possible explanation for this finding is that the proportion of therapy types differed between general practitioners and specialists. A higher proportion of patients treated by general practitioners than those treated by specialists received OAD therapy, whereas a higher proportion of patients treated by specialists than those treated by general practitioners received insulin therapy. Patients who received insulin therapy had higher HbA1c levels than those who did not receive insulin therapy, regardless of the care provider. The HbA1c levels of patients receiving OAD therapy from general practitioners were lower than those of patients receiving OAD therapy from specialists. General practitioners prescribed fewer OADs than did specialists, and HbA1c levels were found to be associated with the number of OADs prescribed, according to multivariable regression analyses. Our results suggest that specialists may treat patients who have a greater difficulty in achieving glycemic control and need to undergo intensive treatments such as insulin therapy or multiple combined OAD therapy.
General practitioners were more reluctant to intensify treatment for patients with T2DM, e.g., by initiating insulin or drug intensification, and specialists were less prone to clinical inertia than were primary care practitioners [13, 16]. Under these circumstances, the appropriate response of general practitioners to elevated HbA1c levels would be to consult with a specialist. Accessibility to specialists may be a critical factor for smooth consultation, and the network between general practitioners and specialists may contribute to appropriate diabetes care. In this study, 88.2% of general practitioners indicated that it was easy to consult with specialists. Further, a shared care program between a specialized outpatient clinic and primary healthcare physicians has been shown to be non-inferior to management in a specialized outpatient clinic . Another study has shown that training and continuous communication between primary care physicians and endocrinologists resulted in improvements in metabolic control among patients with diabetes and vascular disease in a primary setting . In Italy, althpigh diabetic specialists have been endeavored for improving diabetic care [20, 21], for further improvement, a recent ongoing study is examining whether integrated care by general practitioners, diabetologists, and cardiologists can afford better outcomes in a population at-high-risk patients with diabetes . Our study suggests that general practitioners may consult with specialists in a timely manner at the step of therapy intensification, such as the addition of a fourth OAD or more than four OADs or at the initiation of insulin therapy. In our study, the HbA1c level that general practitioners wished to consult with specialists about was higher than that for which specialists preferred to be consulted. In concordance with the findings of these reports, the network between general practitioners and specialists is expected to be bidirectional. In other words, not only should general practitioners consult with specialists but specialists should also inform general practitioners of guidelines and provide them with knowledge on new drugs as well as methods for initiation of insulin.
Weight control in patients with T2DM is a concern for physicians because BMI is associated with HbA1c values . In our study, the BMIs of patients with T2DM cared for by general practitioners were found to be higher than those of patients cared for by specialists, especially among those with higher HbA1c levels. For weight management, lifestyle interventions, such as medical nutrition therapy, physical activity, and self-management education, and psychological support are necessary . Many co-medical staff members need to participate in the education and empowerment of patients to introduce lifestyle changes. However, these collaborations may be difficult among general practitioners. Even among patients with T2DM and a good glycemic control status, such as HbA1c levels < 7.0%, the BMI of patients cared for by specialists was lower than that of those cared for by general practitioners. This suggests that specialists may conduct the weight control in all patients with T2DM, regardless of their HbA1c levels. The association between BMI and all-cause mortality among patients with T2DM shows a U-shaped curve, and both lean and obese patients show an increased risk for all-cause mortality . Further, the Jichi Medical School Cohort Study in Japan showed that the risk of all-cause death in elderly patients with diabetes was substantially higher than that in lean patients of all ages, whereas the risk of all-cause death in obese patients was restricted to patients aged < 65 years . According to these reports, the weight management of patients with T2DM cared for by general practitioners was acceptable, except for those with high HbA1c levels.
Hypertension is common among patients with diabetes. Furthermore, it is a strong and modifiable risk factor for macrovascular and microvascular complications of diabetes . Meta-analysis of clinical trials revealed that antihypertensive treatment of populations with diabetes and baseline blood pressure < 140/90 mmHg reduces the risk of atherosclerotic cardiovascular disease (ASCVD), heart failure, retinopathy, and albuminuria [26,27,28]. Therefore, most patients with diabetes and hypertension should be treated maintaining a target blood pressure of at least < 140/90 mmHg. A target blood pressure lower than < 149/90 mmHg may be beneficial for selected patients with diabetes. However, the JDS and the Japanese Society of Hypertension recommend that the target level of office blood pressure in patients with diabetes be < 130/80 mmHg and an ACEi/ARB be used as a first-line antihypertensive drug because of its organ-protective and insulin-sensitizing properties [29, 30]. An ACEi/ARB is also recommended as a first-line treatment for hypertension in patients with T2DM and albuminuria in a position statement from the American Diabetes Association . The EUROASPIRE IV survey showed that only 54% of patients with diabetes achieved a target blood pressure < 140/90 mmHg . Canada is another country whose guidelines have retained a target blood pressure < 130/80 mmHg, and the achievement rate was 36% among patients with T2DM . In concordance with these reports, the target blood pressure (< 140/90 mmHg) achievement rates of 73.2% and 73.3% for patients with T2DM cared for by general practitioners and specialists, respectively, in our study appear to be adequate and similar to the findings of a Canadian report (< 130/80 mmHg; 37.7% and 40.0%, respectively). Our results that diabetes specialists prescribe ACEi/ARB more often than general practitioners also suggest that specialists may focus on albuminuria and may consider the prevention of renal function more than general practitioners.
The limitations of this study include the sample size and nature of the participants. We randomly selected approximately 15% of the JMDPIMC members for study eligibility, and 6.9% participated in this study. In addition, it is likely that the majority of practitioners who agreed to participate in this study had an interest in diabetes care, considering participation was voluntary. However, the ratio of specialists to general practitioners in this study was 16.8%, which is close to the ratio of certified diabetologists to general practitioners in Japan. Further, we did not collect precise information about the patients, such as duration of diabetes and complications, because the method of data collection was administration of a questionnaire among the busy practitioners. This study was cross-sectional; therefore, we could not clarify how the quality of diabetic care of general practitioners or specialists could contribute to improve the HbA1c levels.
In summary, the median HbA1c level of all patients treated by general practitioners was slightly lower than that of patients treated by specialists in this study. This suggests that collaboration between general practitioners and specialists is appropriate for managing patients with diabetes in Japan. In addition, blood pressure control by general practitioners was adequate and weight control was acceptable, except in patients with high HbA1c levels. The present study clearly demonstrated that many patients with T2DM are appropriately cared for by general practitioners instead of diabetes specialists in Japan, although the number of diabetes specialists is insufficient to cover all patients with diabetes. Finally, to match the constant increase in demand for diabetes care, provision of adequate quality of care by general practitioners is a solution to decrease the complications of diabetes and improve the quality of life of patients with diabetes. Our investigation may contribute to the policy of public health services in every country.