Health Outcome Effects of Common Medications in Elders With Multiple Conditions

Background/Aims: Determining medication effects is more complex in individuals with multiple chronic conditions (MCC). One approach to addressing these limitations is to define effectiveness through the use of cross-condition, universal health outcomes such as self-reported health (SRH). Appropriate methodology is needed to evaluate medication effects in the setting of MCC. Methods: We studied 9 commonly used oral medications from national disease guidelines (renin-angiotensin system blockers (RAS), statins, thiazides, calcium channel blockers, selective serotonin reuptake inhibitors, metformin, warfarin and clopidogrel) recommended for 8 common chronic conditions (atrial fibrillation, coronary artery disease, depression or anxiety, diabetes mellitus, heart failure, hyperlipidemia, hypertension and pulmonary embolism/venous thrombosis) and used by at least 20% of 8,517 Medicare Current Beneficiary Survey enrollees with two or more MCC from 2005–2009 with follow-up data available through 2011. We estimated the odds of high SRH (good-excellent) of the most commonly used medications for 8 common and morbid chronic conditions, adjusted for 14 covariates and accounting for within-subject correlation. For absolute population level estimates, we applied the longitudinal extension of the average-attributable-fraction with time-varying conditions on recurrent SRH. Results: The most common dyads of conditions at baseline were hypertension and hyperlipidemia, with 71.3% (6,073 of 8,517). On average, 11.3% (96 of 8,517) discontinued a medication over the 3-year follow-up period, whereas 6.9% (588 of 8,517) started a new medication. All the conditions except atrial fibrillation were significantly associated with poorer SRH; pulmonary embolism/venous thrombosis had borderline significance. Hyperlipidemia had significantly higher odds of high SRH. There were four significant condition-medication interaction terms. Regarding participants with hypertension, the odds of high SRH for people who take RAS blockers were greater than those who do not. Conversely, the odds of high SRH for people who take thiazide for hypertension are lower than those who do not. The odds of reporting high SRH for people taking statins is higher than those not taking statins within the hyperlipidemia subpopulation. The odds of high SRH among people who have coronary artery disease is lower in those who take clopidogrel than those who do not. Discussion: Medication effects on universal health outcomes provide a way to compare across conditions