The prevalence and ingredient cost of chronic comorbidity in the Irish elderly population with medication treated type 2 diabetes: A retrospective cross-sectional study using a national pharmacy claims database

Abstract

BackgroundComorbidity in patients with diabetes is associated with poorer health and increased cost. The aim of this study was to investigate the prevalence and ingredient cost of comorbidity in patients ≥ 65 years with and without medication treated type 2 diabetes using a national pharmacy claims database.MethodsThe Irish Health Service Executive Primary Care Reimbursement Service pharmacy claims database, which includes all prescribing to individuals covered by the General Medical Services scheme, was used to identify the study population (≥ 65 years). Patients with medication treated type 2 diabetes (T2DM) were identified using the prescription of oral anti-hyperglycaemic agents alone or in combination with insulin as a proxy for disease diagnosis. The prevalence and ingredient prescribing cost of treated chronic comorbidity in the study population with and without medication treated T2DM were ascertained using a modified version of the RxRiskV index, a prescription based comorbidity index. The association between T2DM and comorbid conditions was assessed using logistic regression adjusting for age and sex. Bootstrapping was used to ascertain the mean annual ingredient cost of treated comorbidity. Statistical significance at p < 0.05 was assumed.ResultsIn 2010, 43165 of 445180 GMS eligible individuals (9.7%) were identified as having received medication for T2DM. The median number of comorbid conditions was significantly higher in those with T2DM compared to without (median 5 vs. 3 respectively; p < 0.001). Individuals with T2DM were more likely to have ≥ 5 comorbidities when compared to those without (OR = 2.82, 95% CI = 2.76-2.88, p < 0.0001). The mean annual ingredient cost for comorbidity was higher in the study population with T2DM (€1238.67, 95% CI = €1238.20 - €1239.14) compared to those without the condition (€799.28, 95% CI = €799.14 - € 799.41).ConclusionsIndividuals with T2DM were more likely to have a higher number of treated comorbid conditions than those without and this was associated with higher ingredient costs. This has important policy and economic consequences for the planning and provision of future health services in Ireland, given the expected increase in T2DM and other chronic conditions.

Study design and baseline characteristics of inpatients with diabetes mellitus in a tertiary hospital in China: A database study based on electronic medical records

“…The proportion of patients with coexisting diabetes and hypertension in our study was higher than that reported by EMR‐based studies in other countries. An analysis of ambulatory adult T2DM patients in a center in the United States demonstrated a prevalence of 17.8%, while a study in Ireland found 32.2% T2DM patients on antihypertension therapy . This diversion might be a consequence of the heterogeneity of patients’ characteristics.…”

The prevalence of Type 2 diabetes and related complications in a nationally representative sample of adults aged 50 and over in the Republic of Ireland

“…Regional data from Ireland have shown that the prevalence of diagnosed Type 2 diabetes among middle‐aged primary care patients ranged from 2.8% in 1998 to 5% in 2010–2011 . Cross‐sectional analysis of a national prescription database demonstrated a higher prevalence (9.1%) among adults aged over 65 years in 2010 . Type 2 diabetes is a significant cause of blindness, non‐traumatic lower limb amputations, end‐stage renal disease and cardiovascular disease .…”

“…Similar to other countries, Ireland does not have a national diabetes register or universal data‐capture system to monitor the burden of Type 2 diabetes and related complications. Prevalence estimates rely on data from observational studies . However, these estimates can vary due to differences in age ranges, study populations and case finding methods; comparability between studies is limited, making it difficult to observe trends over time .…”

Pharmaceutically treated comorbidities and associated healthcare costs among triptan users in Switzerland: A pharmacoepidemiological study from a nationwide health insurance database

“…However, epidemiological data on the medical and economic burden are very scarce and in absence of valid population‐based clinical data on migraine, healthcare claims data provide a valuable source for (pharmaco‐)epidemiological research . These data are reliable, longitudinal, comprise a large number of residents, can be seen as representative to the general population, and are widely used in epidemiological research to determine the prevalence of chronic diseases . Second, our cost estimates are not able to reflect the total cost‐of‐illness since data on indirect costs such as productivity losses due to work absenteeism were not available.…”

“…However, since all prescription drug items are coded and assigned to a respective ATC code in our database, we were thus able to assign certain ATC codes to different chronic diseases. In administrative databases, this mapping approach allows us a direct measure of treated diseases, and represents in the meanwhile a commonly used and reliable method to identify patients with chronic diseases . Furthermore, these drugs include the drug groups which were most frequently prescribed in primary care in Switzerland and, therefore, were likely to cover the majority of relevant drugs prescribed in real‐life patients .…”