Both cardiovascular and non-cardiovascular comorbidity are related to health status in well-controlled type 2 diabetes patients: a cross-sectional analysis

BACKGROUND: Type 2 diabetes patients have a decreased health-related quality of life compared to healthy persons, especially regarding physical functioning and well-being. Health-related quality of life is even lower in type 2 diabetes patients when other diseases co-exist. In contrast to earlier studies, we assessed the associations between the number and type of comorbidities and health status in well-controlled type 2 diabetes patients, in whom treatment goals for HbA1c, blood pressure and cholesterol had been reached. Approximately one in five type 2 diabetes patients belongs to this group. METHODS: Cross-sectional analysis was performed in 2086 well-controlled (HbA1c ≤58 mmol/mol, systolic blood pressure ≤145 mmHg, total cholesterol ≤5.2 mmol/l and not using insulin) type 2 diabetes patients in general practice. Both number and type (cardiovascular and non-cardiovascular) of comorbidities were determined for each patient. Health status was assessed with the questionnaires Short Form-36 (SF-36) and EuroQol (EQ). The SF-36 generates eight dimensions of health and a Physical and Mental Component Score (PCS and MCS), scale: 0–100. The EQ consists of two parts: EQ-5D and EQ Visual Analogue Scale. Multivariable linear regression analysis was used to assess if number and type of comorbidities were associated with health status. RESULTS: Well-controlled type 2 diabetes patients with comorbidities had a much lower health status, with a decrease ranging from -1.5 for the MCS to -26.3 for role limitations due to physical problems, compared to those without. Health status decreased when the number of comorbidities increased, except for mental health, role limitations due to emotional problems, MCS and both EQ measures. In patients with both cardiovascular and non-cardiovascular comorbidity, physical functioning, role limitations due to physical problems and PCS were significantly lower than in patients with only cardiovascular comorbidity. Physical functioning was also lower compared to patients with only non-cardiovascular comorbidity. CONCLUSIONS: Even acceptable values of HbA1c, blood pressure and cholesterol in type 2 diabetes patients are not necessarily related with a good health status. We have shown that comorbidities have a large impact on health status. Physicians may take into account patient’s health status and integrate the impact of comorbidities into diabetes care.