Correlates of health-related quality of life in French people with type 2 diabetes

Abstract

Aim

Diabetes is known to impair health-related quality of life (HrQol). Our aim was to analyse a comprehensive set of potential determinants of HrQol in a large sample of patients with diabetes.

Methods

This study is based on the ENTRED 2007 study, a representative sample of adults (18 years and older) with diabetes. Data were extracted from postal self-reported questionnaires (from patients and medical practitioners) and from reimbursements from the National health insurance data system. HrQol was assessed with the MOS SF-12 for mental (MCS) and physical (PCS) component summaries. Multivariate linear regression models were used to analyse the variables associated with HrQol.

Results

SF-12 MCS and PCS were available in 2832 patients with T2DM, with a mean age 64 years (1715 males, 56%). Lower income, severe hypoglycaemic episodes, hospitalisation ≥24 h, instrumental daily living (IADL) restriction, low satisfaction for social support and an HbA1c within the 8.1–10.0% range were associated with lower MCS rating, whereas an older age and male gender were associated with higher MCS. Older age, female sex, higher BMI, lower income, insulin treatment, macrovascular complications, severe hypoglycaemic episodes, hospitalisation ≥24 h, and IADL restriction were associated with lower PCS values whereas having no need for social support was associated with higher PCS values.

Discussion

HrQol associated factors are multiple but mainly linked with socio-demographic factors, diabetes complications and satisfaction for social support. A patient centred approach should be tested to prevent impairment of HrQol and thus to decrease the burden of diabetes. Assessment of social support should be included.

Introduction

Type 2 diabetes (T2D) is one of the most frequent chronic diseases in adults reaching 3.2% in French people older than 18 years and 11% in those older than 65 years [1]. The burden of diabetes is known to be heavy, as it involves high rates of disability, participation restrictions and decreased life expectancy. The health burden of diabetes is associated with an increasing economic burden, particularly in the oldest [2]. Effective interventions are thus needed to decrease these negative impacts in various populations with diabetes.

Patient's perception of his/her own quality of life is considered as a valuable basis to identify targets for improvement. Health-related quality of life (HrQoL) is therefore one of the major end-points of recent clinical trials in people with diabetes [3], [4]. HrQoL assessment with the generic instrument SF-36 or its shorter version SF-12 has been used in people in T2D along with diabetes-specific instruments. The SF12 questionnaire is an instrument used to measure overall physical and mental health. Using a generic instrument allows comparisons with the general population. In France, in 2003, a previous large cross-sectional study obtained SF-36 scores in 22,743 community dwellers aged 18–84 years old including 3.4% patients with diabetes [5]. Diabetes was shown to be a predictor of lower scores in all of the 8 subscales independently of socio-economic status and diseases such as ischaemic heart disease, heart failure, cancer and hypertension. Similar results have been shown in German [6] or Korean populations [7]. However, in people with T2D and with diverse co-morbidities, the impact of diabetes on HrQoL is not easily distinguishable from that of other diseases or disabilities [8], [9]. Previous studies investigating HrQoL in populations with T2D may have been of limited power due to limited sample sizes [10], [11], [12], [13], or may have addressed only specific populations [14], [15], [16]. In a study focused on 7606 people with chronic diseases, including 14% people with diabetes, factors associated with lower HrQoL scores were not limited to the disease and its consequences but depended strongly on socio-economic factors [17]. Thus, although it has been shown that HrQol was associated with the characteristics of the diabetes disease [18], estimating the respective contribution of diverse factors on HrQol is necessary to better evaluate any intervention. For this purpose, a high power study is needed to assess the relative influences of multiple factors on HrQol.

Using the large ENTRED 2007 cross-sectional study (Échantillon national témoin représentatif des personnes diabétiques), based on a representative of adults with diabetes living in metropolitan France in 2007 [19], the aim of our analysis was to assess HrQol in people with T2D and to estimate the relative contributions of socio-demographic factors, diabetes characteristics, complications and treatment, social support and functional impairment in daily living, in mental and physical components of HrQol.