In a patient's 10-day drug history, what score is significant?

Significance of Score in 10-Day Drug History

In a patient's 10-day drug history, a score of 4 or more medications is considered significant as it increases the risk of drug-related problems, adverse events, and medication errors. 1

Understanding Medication History Significance

Medication histories are crucial components of patient assessment that help prevent prescription errors and identify potential drug-related issues. The British Journal of Pharmacology guidelines emphasize that accurate medication histories are essential for:

• Preventing prescription errors and consequent risks to patients
• Detecting drug-related pathology
• Identifying changes in clinical signs resulting from drug therapy 1

Key Risk Thresholds

The significance of medication numbers in a patient's history follows specific thresholds:

• 4+ medications: Increases risk of medication errors and adverse drug events 2
• 5+ medications: Established criterion for identifying patients at high risk for drug-related problems 2
• 9+ medications: Increases fall risk by 50% and nearly doubles mortality risk (adjusted odds ratio 1.96) in older adults 3

Risk Factors for Adverse Drug Events

Several factors contribute to the significance of a patient's medication history:

1. Number of medications:

   • Each additional medication increases the likelihood of drug-related problems 3
   • Five or more medications is a validated criterion for identifying high-risk patients 2

2. Medication regimen complexity:

   • 12+ doses per day
   • 4+ changes to medication regimen within recent period 2

3. Patient characteristics:

   • Female gender (OR 1.5-1.7)
   • Age (variable impact)
   • Weight (OR 1.2-1.4)
   • Renal function (creatinine clearance) (OR 0.8-4.7)
   • Number of comorbidities (OR 1.1-12.6) 4

4. Drug administration factors:

   • Dosage (OR 1.2-3.7)
   • Administration route (OR 1.4-149.9)
   • Number of concomitant drugs (OR 1.2-2.4) 4

Accuracy of Medication Information Sources

When collecting a 10-day drug history, the accuracy of information sources varies significantly:

• Residential care facility charts: Most accurate (median 0 discrepancies)
• Patient's medication list: Moderate accuracy (median 2.5 discrepancies)
• Community pharmacy history: Less accurate (median 3.0 discrepancies)
• Patient's own medications: Least accurate (median 4.0 discrepancies) 5

Strategies to Improve Medication History Accuracy

To ensure accurate medication histories:

• Have pharmacists obtain medication histories when possible, as they are more accurate than physicians or nurses 1
• Use multiple sources to determine the best possible medication history 5
• Document all currently and recently prescribed drugs, previous adverse reactions, over-the-counter medications, and herbal/alternative medicines 6
• Assess adherence to therapy 6

Clinical Implications

The significance of a patient taking 4 or more medications extends beyond just the number:

• 67% of medication histories have at least one prescription error
• 22% of these errors have the potential to significantly harm the patient 1
• Over one-third (34%) of community-dwelling older adults have at least one type of drug interaction 7
• Each additional prescription medication increases the odds of having a drug interaction by 35-40% 7

By recognizing the significance of 4+ medications in a patient's 10-day drug history, clinicians can implement appropriate medication review strategies to minimize risks and improve patient outcomes.