Orbidity burden increased, adherence to osteoporosis treatment decreased whereas adherence to medications used to treat hypertension and hypercholesterolemia increased. While non-adherence in certain other chronic conditions (for example, hyperlipidemia) may not be associated with shortterm consequences, interruptions in ULD use can trigger or prolong acute gout attacks [3,4]. The most recent publication looking at predictors of adherence in gout patients was focused on the elderly (mean age of the study population was 79), and the overwhelming majority of patients were women [13]. That study population is not representative of patients typically followed in an outpatient medical practice. Therefore, more investigation in the rates and causes of non-adherence in the treatment of gout is SCH 530348 biological activity necessary, particularly in men and younger populations. Specifically, the objective of this study was to analyze the rates and predictors of non-adherence with ULDs in a representative sample of gout patients. We hypothesized that patients with more frequent gout attacks would be more adherent.Study population and design We identified members from the dataset who had an International Disease Classification, version 9 (ICD-9) code for a gout diagnosis (codes 274.XX), were aged 18 years or older at the time of the first ULD dispensing, were dispensed a ULD (allopurinol, probenecid or sulfinpyrazone) between 1 January 2000 and 30 June 2006 and were continuously enrolled in the health plan with drug coverage during the period 12 months prior to and 12 months following the first ULD dispensing. Our analysis focused on new users of therapy, which was defined as no dispensing of a ULD in the prior 6 months. Adherence measure We used the medication possession ratio (MPR) to measure adherence [16]. The MPR was calculated as the days supply of medication dispensed during the follow-up year divided by the number of days in the year and is a reliable measure of adherence [17]. The MPR was determined based on pharmacy dispensing records, including the number of days supplied. Use of the MPR allowed comparisons with other studies who used similar methods in examining adherence to ULDs [11-13]. As has been performed in other prior studies, the MPR was dichotomized at 80 in multivariable analyses, with an MPR of <80 considered non-adherence [11-13]. Covariates and measures Patient characteristics were assessed, including those covariates identified as potential correlates of adherence based on previous studies [11-13,18]. These included demographic factors (age and sex), health care utilization (visits to providers for gout both prior to and after ULD initiation, all provider visits prior to ULD initiation, and number of hospitalizations prior to ULD initiation), specific comorbidities, other medications used to treat symptomatic gout, and medications that can trigger gout. Age (as of first ULD dispensing) and sex were ascertained from the demographic data. We ascertained the presence of comorbidities from the ICD-9 diagnosis codes associated with ambulatory, emergency department, and inpatient care during the time period 12 months prior to and 12 months following the first PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/27385778 ULD dispensing. Comorbidities of interest included coronary heart disease, diabetes mellitus, dyslipidemia, hypertension, nephrolithiasis, peripheral arterial disease, renal insufficiency and renal failure. A Charlson comorbidity score (the score does not include a gout diagnosis) was ascertained b.
