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Stars Navigator · Measure Reference

Polypharmacy and Opioid Safety: Poly-ACH and COB

Two Part D patient safety measures added to the 2027 Star Ratings (MY2025) at a weight of 1 each. Both are inverse measures: they report the percentage of members with 30 or more cumulative days of concurrent use, and lower rates indicate better performance.

Measure steward

PQA

Data source

Part D PDE

Weighting category

Process

2027 Star weight

1 each

Direction

Lower is better

Period

Calendar year

Specification

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	Poly-ACH	COB
Full name	Polypharmacy: Use of Multiple Anticholinergic Medications in Older Adults	Concurrent Use of Opioids and Benzodiazepines
Denominator	Members 65 and older with at least two claims for the same anticholinergic medication on different dates of service	Members 18 and older with at least two opioid claims on different dates of service totaling at least 15 days' supply
Numerator	Two or more unique anticholinergic medications, each with at least two claims, with 30 or more cumulative days of concurrent use	At least two benzodiazepine claims on different dates of service, with 30 or more cumulative days of concurrent opioid use
Exclusions	Hospice	Hospice, palliative care, cancer, sickle cell disease
Value set notes	Aligned with the AGS Beers Criteria list of strongly anticholinergic drugs	Buprenorphine products indicated for opioid use disorder are excluded from the opioid list

Operational work should use the PQA value sets for the applicable measurement year.

Calculation

Concurrent use is measured from overlapping days' supply. Overlap can accrue in separate episodes across the year, and once a member reaches 30 cumulative days the result is fixed for the measurement year.

Medication A

Medication B

Concurrent use

Day 1

Day 30

Day 60

Day 90

Day 120

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Cumulative concurrent days	Result
29	Not in the numerator
30 (10 + 10 + 10)	In the numerator for the measurement year

Figure 1. Concurrent use is cumulative, not consecutive. Medication A and B represent two unique anticholinergics (Poly-ACH) or an opioid and a benzodiazepine (COB). Illustrative 120-day window.

Clinical and operational considerations

Anticholinergic burden is cumulative. In older adults it is associated with cognitive impairment, delirium, falls, constipation, and urinary retention.
Common Poly-ACH contributors include bladder antimuscarinics (oxybutynin, solifenacin), first-generation antihistamines (hydroxyzine, meclizine), tricyclic antidepressants (amitriptyline), paroxetine, and some antipsychotics.
Lower-burden alternatives exist for many indications, such as a beta-3 agonist for overactive bladder, a second-generation antihistamine, or an SSRI other than paroxetine.
Opioid and benzodiazepine co-prescribing carries an FDA boxed warning for profound sedation, respiratory depression, and death. Naloxone should be offered when concurrent use continues.
Benzodiazepines require a gradual taper. Abrupt discontinuation risks withdrawal and seizures, so closing a COB gap is a clinical plan, not a stop order.
Prescribers often see only half the combination. Concurrent use frequently spans prescribers and pharmacies, which is why claims-level detection matters.

Member scenarios

How common claim patterns resolve in each measure. Members are illustrative; days' supply and fill dates drive the result, not the clinical intent behind them.

Poly-ACH

#1 · Member A, age 78

Two anticholinergics, 30+ concurrent days

Qualifying drugs

Qualifying concurrent days

✓ Numerator

Amitriptyline and oxybutynin, each filled three times on different dates, run concurrently for 80 days. A clear numerator case and a real anticholinergic burden concern.

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Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

amitriptyline

30d

oxybutynin

30d

Concurrent

80d

amitriptyline

oxybutynin

Concurrent days

Faded bars do not count toward the measure.

#2 · Member B, age 71

Second drug has a single claim

Qualifying drugs

Qualifying concurrent days

Denominator only

Oxybutynin qualifies, and a 30-day hydroxyzine fill overlaps it completely, but hydroxyzine has only one claim. Each unique drug needs at least two claims on different dates, so none of the overlap counts.

Swipe to see the full year →

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

oxybutynin

30d

hydroxyzine

30d

Concurrent

30d

oxybutynin

hydroxyzine

Concurrent days

Faded bars do not count toward the measure.

#3 · Member C, age 76

Short courses add up

Qualifying drugs

Qualifying concurrent days

✓ Numerator

Two separate 15-day meclizine courses, in March and August, overlap daily paroxetine. Concurrent use is cumulative, so 15 plus 15 reaches the 30-day threshold.

Swipe to see the full year →

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

paroxetine

30d

meclizine

15d

Concurrent

15d

paroxetine

meclizine

Concurrent days

Faded bars do not count toward the measure.

#4 · Member D, age 69

A switch that reads as concurrent use

Qualifying drugs

Qualifying concurrent days

✓ Numerator

The prescriber switched oxybutynin to solifenacin on June 15, but the June 1 oxybutynin fill carried 90 days' supply. Claims show 60 concurrent days, so a clinically sound switch lands in the numerator.

Swipe to see the full year →

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

oxybutynin

90d

solifenacin

30d

Concurrent

60d

oxybutynin

solifenacin

Concurrent days

Faded bars do not count toward the measure.

COB

#5 · Member G, age 58

Opioid supply below the threshold

Opioid days' supply

Concurrent days

Not in measure

Two 7-day hydrocodone fills after surgery total 14 days' supply, one day short of the 15-day denominator threshold. The concurrent lorazepam use never enters the calculation.

Swipe to see the full year →

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

hydrocodone

lorazepam

30d

Concurrent

14d

hydrocodone

lorazepam

Concurrent days

Faded bars do not count toward the measure.

#6 · Member J, age 72

Only one benzodiazepine claim

Opioid days' supply

Concurrent days

Denominator only

Oxycodone qualifies the member, and a single 60-day alprazolam fill overlaps it for 60 days, but the numerator requires at least two benzodiazepine claims on different dates.

Swipe to see the full year →

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

oxycodone

30d

alprazolam

60d

Concurrent

60d

oxycodone

alprazolam

Concurrent days

Faded bars do not count toward the measure.

#7 · Member K, age 63

Opioid and benzodiazepine, 30+ concurrent days

Opioid days' supply

Concurrent days

✓ Numerator

Oxycodone and clonazepam, each filled three times on different dates, run concurrently for 85 days. Opioids meet the two-claim and 15-day criteria, and the benzodiazepine has two or more claims.

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Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

oxycodone

30d

clonazepam

30d

Concurrent

85d

oxycodone

clonazepam

Concurrent days

Faded bars do not count toward the measure.

#8 · Member L, age 70

An appropriate taper still counts

360

Opioid days' supply

Concurrent days

✓ Numerator

A diazepam taper dispensed as two 15-day fills runs alongside daily oxycodone. Concurrent use reaches exactly 30 days, so the taper lands in the numerator. A shorter overlap would not.

Swipe to see the full year →

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

oxycodone

30d

diazepam

15d

Concurrent

30d

oxycodone

diazepam

Concurrent days

Faded bars do not count toward the measure.

Exclusions and eligibility

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Member	Claims in the measurement year	Result	Why
E, age 82	Amitriptyline and oxybutynin, each filled monthly. Hospice enrollment in November.	Excluded	Hospice at any point in the measurement year removes the member from Poly-ACH.
F, age 61	Same claims pattern as Member A.	Not in measure	Poly-ACH is limited to members 65 and older.
M, age 45	Buprenorphine/naloxone for opioid use disorder. Clonazepam monthly.	Not in measure	Buprenorphine products for OUD are excluded from the COB opioid list.
N, age 67	Morphine and lorazepam, each filled monthly, with a cancer diagnosis.	Excluded	Cancer, sickle cell disease, hospice, and palliative care are excluded from COB.

Policy watch

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	Change
2027 Star Ratings (MY2025)	Poly-ACH and COB enter the Star Ratings at a weight of 1 each. Poly-CNS remains on the display page.
Cut points	As new measures, Poly-ACH and COB are not covered by the 5-percentage-point guardrail in their first year.
Measure set	Eleven administrative measures are removed across the 2028 and 2029 Star Ratings. Weights are unchanged, so each remaining measure carries a larger share of the summary and overall ratings.
Litigation	After Clover v. HHS (S.D. Ga., May 2026), CMS excluded all Part D measures from its recalculated 2027 QBP ratings and has appealed to the 11th Circuit. Poly-ACH and COB remain in the 2027 Star Ratings measure set.

References

CMS. 2027 Star Ratings Measures and Weights.
Pharmacy Quality Alliance. Poly-ACH and COB measure specifications.
American Geriatrics Society. 2023 Updated AGS Beers Criteria for Potentially Inappropriate Medication Use in Older Adults.
U.S. Food and Drug Administration. Drug Safety Communication on opioid and benzodiazepine co-prescribing (2016).
CMS. Contract Year 2027 Medicare Advantage and Part D Final Rule (CMS-4208-F3), April 2, 2026.
Clover Insurance Co. v. HHS (S.D. Ga., May 27, 2026); CMS memorandum on 2027 Quality Bonus Payment recalculation, June 17, 2026.

Specifications are summarized for education. Consult the PQA measure specifications and CMS Star Ratings Technical Notes for the measurement year in question. Prepared by the MedWatchers clinical pharmacy team, October 2026.