Health care utilization and costs following amplified versus non-amplified molecular probe testing for symptomatic patients with suspected vulvovaginitis: a US commercial payer population

Abstract

Background

Vulvovaginitis (VV) is a common reason women seek medical attention in the USA. Both the non-specific clinical presentation and risk of preterm labor or delivery necessitate accurate identification of the causative agents to guide appropriate therapy. The diagnostic accuracy of amplified molecular probe testing (AMP) has been shown to exceed that of non-amplified molecular probe (NAMP) by 20%–25%.

Objective

To evaluate the impact of diagnosis with AMP testing on health care utilization, direct costs, and health outcomes, compared with NAMP, for symptomatic patients with suspected VV from a commercial payer perspective.

Methods

Symptomatic women (aged 18–64 years) who underwent VV testing with AMP or NAMP from January 1, 2012–December 31, 2016 were identified using the Truven Health Analytics MarketScan Database; those with continuous medical and pharmacy benefit enrollment 6 months pre/post AMP or NAMP testing were included. Patients were propensity score (PS) matched and 6-month all-cause health care resource utilization, all-cause direct costs (2017 USD), risk of all-cause hospitalization, and risk of preterm labor or delivery were compared between cohorts.

Results

After PS match (N=46,810 per group, mean age 34.2 years), AMP had significantly (all P<0.0001) fewer mean hospital outpatient visits (AMP 0.9 vs NAMP 1.0), primary care physician office visits (AMP 1.1 vs NAMP 1.2), and prescription medications (AMP 7.3 vs NAMP 8.0), and a 21% reduction in risk of hospitalization (risk ratio [RR]=0.79, 95% CI= 0.75–0.83, P<0.0001). Total medical expenditures per patient were lower for AMP than NAMP (mean AMP $3,287 vs NAMP $3,555, P<0.0001). Among pregnant women (N=2,175 per group), AMP had a 12% reduction in risk of preterm labor or delivery (RR =0.88, 95% CI=0.77–0.99, P=0.041).

Conclusion

This real-world study offers evidence on the clinical utility for symptomatic patients with suspected VV diagnosed with AMP compared to NAMP – demonstrating an opportunity to improve the patient journey while delivering value-based care.

Keywords:

• vulvovaginitis
• preterm labor
• preterm delivery
• amplified molecular probe testing
• propensity-score matching
• health care utilization
• costs
• NuSwab
• clinical utility

Supplementary material

Table S1 Current procedure terminology codes for identifying testing cohorts

Table S2 Diagnosis codes and drugs for identifying pre-index vulvovaginitis

Table S3 Current procedure terminology codes for vulvovaginitis diagnostic tests

Table S4 Diagnosis codes for malignancy

Table S5 Diagnosis codes for pregnancy

Table S6 Diagnosis codes for preterm labor and delivery

Table S7 Comorbid condition diagnosis codes and drugs of interest

Acknowledgments

The authors thank Rebecca Baik of Covance Market Access Services Inc. for her contributions to the statistical analysis plan and programming; Rachael Mann of Covance Market Access Services Inc. for medical writing and editorial support in the development of this manuscript; and Tawana McIver of Laboratory Corporation of America Holdings for providing ICD-9-CM and ICD-10-CM codes. This study was supported by Laboratory Corporation of America Holdings (LabCorp; Burlington, NC, USA). LabCorp supported this research by acquiring the claims data extract.

Disclosure

At the time of this study, Dr Ackerman, Mr Knight, and Dr Wahl were employed by Covance Inc., which is wholly owned by LabCorp, and Dr Cartwright was employed by LabCorp. Dr Ackerman and Mr Knight are shareholders in LabCorp. Dr Cartwright is an inventor on issued patents (9,057,111; 9,624,552; 9,970,064) relevant to this work and is a shareholder in LabCorp. The authors report no other conflicts of interest in this work.