Disproportionate longer-term opioid use among U.S. adults with mood disorders.

Adults with mood disorders frequently use prescription opioids. The factors associated with this increased use remain unclear. We used the Medical Expenditure Panel Surveys from 2005 to 2011 to measure the association of mood disorders with new opioid use and the transition to longer-term opioid use for a variety of pain conditions before and after controlling for patient characteristics and clinical disability. We analyzed 33,450 adults with likely acute or potentially chronic pain conditions who were not using opioids at baseline. Among respondents with likely acute pain conditions, those with mood disorders initiated opioids more frequently for that pain condition compared with those without mood disorders (19.3%, vs 17.2%, P = 0.01). After initiation, they also transitioned to longer-term opioid therapy more frequently (11.7% vs 5.3%, P < 0.01). Among respondents with potentially chronic pain conditions, adults with mood disorders initiated opioid therapy more frequently for their chronic pain condition (11.5% vs 9.2%, P < 0.01) and transitioned to longer-term therapy more frequently (36.8% vs 19.9%, P < 0.01). After adjusting for sociodemographics and clinical disability, there was no association between mood disorders and new opioid use for likely acute (adjusted odds ratio [aOR] 1.05 [0.92-1.20]) or potentially chronic pain (aOR 0.91 [0.80-1.03]). However, there remained a strong association between mood disorders and the transition to longer-term opioid use for likely acute (aOR 1.77 [1.15-2.72]) and potentially chronic pain (aOR 1.95 [1.42-2.68]). Targeting the transition to longer-term opioid use may help clinicians reduce potentially inappropriate opioid prescriptions in this high-risk population.

Multivalent recognition of peptides by modular self-assembled receptors.

Developing nontraditional approaches to the synthesis and characterization of multivalent compounds is critical to our efforts to study and interface with biological systems and to build new noncovalent materials. This paper demonstrates a biomimetic approach to the construction of discrete, modular, multivalent receptors via molecular self-assembly in aqueous solution. Scaffolds presenting 1-3 viologen groups recruit a respective 1-3 copies of the synthetic host, cucurbit[8]uril, in a noncooperative manner and with a consistent equilibrium association constant (K(a)) value of 2 x 10(6) M(-1) per binding site. The assembled mono-, di-, and trivalent receptors bind to their cognate target peptides containing 1-3 Trp residues with K(a) values in the range 1.7 x 10(4)-4.7 x 10(6) M(-1) and in predetermined mono- or multivalent binding modes with 31-280-fold enhancements in affinity and additive enthalpies due to multivalency. The extent of valency was determined directly by measuring the visible charge-transfer absorptivity due to the viologen-indole pair. The predictable behavior of this system and its ease of synthesis and analysis make it well suited to serve as a model for multivalent binding and for the multivalent recognition of peptides by design.