Effect of switching to a high-deductible health plan on use of chronic medications.

Employers and policy makers are increasingly turning to high-deductible health plans (HDHP) to control rising health care costs (Hilzenrath 2010). From 2006 to 2010 the percentage of employees covered by plans with at least a U.S.$1000 deductible increased from 10 percent to 27 percent (Henry J. Kaiser Family Foundation [KFF] 2010). Some analysts expect that the recently passed health insurance reform legislation will lead to an “explosion” in HDHP growth (Kerber 2010). However, the growing popularity of HDHPs has been accompanied by concern that members might underutilize necessary care due to prohibitive cost sharing (Parente, Feldman, and Christianson 2004; Dixon, Greene, and Hibbard 2008). HDHPs require full cost sharing for most services until an annual deductible is met. In 2010, average deductibles for commercial health plans (i.e., HMO, PPO, POS, and savings option plans) with deductibles ranged from U.S.$601 to U.S.$1903 for individuals and U.S.$1321 to U.S.$3780 for families (KFF 2010). HDHPs associated with tax-advantaged Health Reimbursement Accounts (HRAs) or Health Savings Accounts (HSAs) to pay for qualifying medical expenses generally have higher deductibles than plans without spending accounts. Many HDHPs aim to encourage high-value care such as primary care visits and preventive services by excluding them from the deductible (KFF 2010). Although tax laws require that HSA-associated HDHPs fully subject drugs to the deductible, the majority of HDHPs utilize tiered drug copayment structures similar to traditional health plans (KFF 2010). Previous research provides compelling evidence that increased cost sharing reduces health care utilization (Newhouse 1993). The landmark RAND Health Insurance Experiment of 1971–1986 found that patients facing high-level cost sharing reduced overall utilization by approximately 33 percent (Newhouse et al. 1981) and total spending by about 30 percent (Newhouse 1993). Both appropriate and inappropriate utilization decreased, including hospitalizations, outpatient visits, and preventive services (Lohr et al. 1986; Newhouse 1993). The 2007/2008 National Health Interview Survey found that adults in HDHPs had 70 percent more unmet medical or prescription drug needs than adults in traditional health insurance plans (Cohen 2010). Studies have also demonstrated that HDHPs with full cost sharing for prescription drugs alter the use of essential medications for chronic illness, including antihypertensives, statins, cardiac medications, asthma controllers, hypoglycemics, epilepsy medications, and antiulcerants (Greene et al. 2008; Nair et al. 2009; Chen, Levin, and Gartner 2010). However, no studies have examined whether HDHPs that selectively exclude medications from full cost sharing can mitigate or prevent this reduced utilization. Such reductions could still occur if HDHP members (1) reduce contact with physicians due to cost sharing for services such as laboratory testing and radiology (providing fewer opportunities to receive prescriptions), (2) decide that overall increased levels of out-of-pocket payments for services under the deductible exceed their personal health care budget, causing reduced prescription drug purchasing, (3) are confused by complex benefit structures (Marquis 1981; Reed et al. 2009), or (4) experience “sticker shock” and subsequent decreases in generalized utilization because of a very high cost health care event such as an emergency department visit or hospitalization (Wharam et al. 2007). We studied an HDHP that subjected prescription drugs to cost sharing levels typical of traditional health plans. We examined its impact on drugs that reduce morbidity or mortality among patients with major chronic illnesses, including diabetes, hypertension, hyperlipidemia, and chronic pulmonary disease. This research has major policy relevance because most HDHP members nationally face similar drug cost-sharing arrangements (KFF 2010).