Abstract
Background:
Only 10% of patients with alcohol and other drug (AOD) disorders receive treatment. The AOD Initiation and Engagement in Treatment (AOD-IET) measure was added to the national Healthcare Effectiveness Data and Information Set (HEDIS) to improve access to care. This study identifies factors related to improving AOD-IET rates.
Methods:
We include data from seven health systems with differing geographic, patient demographic, and organizational characteristics; all used a common Virtual Data Warehouse containing electronic health records and insurance claims data. Multilevel logistic regression models examined AOD-IET among adults (18+).
Results:
86,565 patients had an AOD diagnosis qualifying for the HEDIS denominator. Initiation rates varied from 26% to 46%; engagement rates varied from 14% to 29%. Women versus men (odds ratio [OR]=0.81, 95% confidence interval [CI]=0.76-0.86), Hispanics (OR=0.85, 95%CI=0.79-0.91), Black/African Americans (OR=0.82, 95%CI=0.75-0.90), and Asian Americans (OR=0.83, 95%CI=0.72-0.95) versus whites, and patients aged 65+ versus 18-29 (OR=0.82, 95%CI=0.74-0.90) had lower odds of initiation. Patients aged 30-49 versus 18-29 (OR=1.11, 95%CI=1.04-1.19), those with prior psychiatric (OR=1.26, 95%CI=1.18-1.35) and medical conditions (OR=1.18, 95%CI=1.10-1.26) had higher odds of engagement. Identification in primary care versus other departments was related to lower odds of initiation (ED: OR=1.55, 95%CI=1.45-1.66; psychiatry/AOD treatment: OR=3.58, 95%CI=3.33-3.84; other outpatient: OR=1.19, 95%CI=1.06-1.32). Patients aged 30-49 versus 18-29 had higher odds of engagement (OR=1.26, 95%CI=1.10-1.43). Patients 65+ versus 18-29 (OR=0.51, 95%CI=0.43-0.62) and Black/African Americans versus Whites (OR=0.64, 95%CI=0.53-0.77) had lower odds. Those initiating treatment in psychiatry/AOD treatment versus primary care (OR=7.02, 95%CI=5.93-8.31) had higher odds of engagement; those in inpatient (OR=0.40, 95%CI=0.32-0.50) or other outpatient settings (OR=0.73, 95%CI=0.59-0.91) had lower odds.
Discussion:
Initiation and engagement varied, but were low. Findings identified age, race/ethnicity, co-occurring conditions and department of identification as key factors associated with AOD-IET. Focusing on these could help programs develop interventions that facilitate AOD-IET for those less likely to receive care.
Keywords: alcohol and drug, performance measures
Introduction
Alcohol and other drug (AOD) use disorders affect more than 20 million people throughout the United States and have a significant impact on the health of individuals, families and society as a whole. The Centers for Disease Control reports more than 2,200 alcohol overdose deaths in the United States each year—an average of six deaths every day. In 2014, 47,055 drug overdose deaths occurred, and 61 percent of these deaths were the result of opioid use, including prescription opioids and heroin.1 These disorders cost $452 billion annually.2 However, access to treatment is low; only 10% of those needing care receive it.3-5
Barriers to treatment have been identified in both treatment initiation and engagement.6, 7 A welcome development in addressing access was the addition of AOD Initiation and Engagement of Treatment (IET) performance measures to the Healthcare Effectiveness Data and Information Set (HEDIS). HEDIS is a set of nationally adopted quality indicators created in 2002 as part of National Voluntary Consensus Standards for Ambulatory Care- Part 1.8 They became mandatory in 2014, yet health systems and the AOD field in general know little about which factors are related to better performance on HEDIS measures. As shown by a review of studies on these measures, the field needs research on the variation across health systems and clinical departments9 to better identify gaps in care and to inform new approaches to improving treatment access.10 For example, the particular clinical settings where diagnoses are identified may impact initiation.11 Co-location of primary care and AOD treatment, internal versus external AOD treatment, and availability of medication assisted treatment may be other clinical factors that improve treatment initiation and engagement.
Understanding how success in meeting HEDIS standards varies by patient-level factors, can help identify disparities and subgroups that could benefit from enhanced referral and engagement strategies. In previous studies, patient-level factors associated with poorer AOD treatment initiation and engagement included female gender, lower AOD problem severity, drug (versus alcohol) dependence, perceived AOD treatment stigma, low motivation, and belief that treatment is ineffective.6, 12-16 The studies showed mixed findings on effects of race/ethnicity: some found non-White individuals more likely to initiate and engage in treatment; others found the opposite.17-22 Also, past studies have focused on data from Medicaid or the Department of Veterans Affairs rather than from private health systems.
The advent of mandatory HEDIS measures and the increased focus on AOD disorders due to the Affordable Care Act’s inclusion of AOD treatment as an essential benefit23 may have changed the organizational and patient level predictors of performance. In this study, we examined both patient and health system factors associated with HEDIS measures of treatment initiation and engagement across seven diverse health systems. Using the Anderson health care utilization framework, the study focused on key utilization predictors based on performance measures24, 25 available in electronic health records (EHRs), As conceptualized here, the model included predisposing characteristics (demographic factors); need (severity, prior year medical and psychiatric comorbidities) and enabling factors (type of health care settings). Our goal was to identify opportunities to develop patient- and system-level interventions that facilitate initiation and engagement in AOD services, particularly among those who may be less likely to receive care.
Methods
Study Participants and Data Sources
This multisite study examined HEDIS AOD IET rates between October 1, 2014 to August 15, 2015 among patients (age ≥18) who qualified for the HEDIS measure denominator with an AOD diagnosis.26, 27 Seven health systems in the Health Care System Research Network (HCSRN)28 of the National Institute on Drug Abuse’s Clinical Trials Network participated in this study. These systems are located throughout nearly all regions of the United States and represent different geographic, patient demographic, and organizational characteristics. They include diverse types of health insurance, including commercial, individual, Medicaid and Medicare plans. They also share a common Virtual Data Warehouse model which uses a common data structure comprised of harmonized data elements from the EHRs and insurance claims data for all health system members. This facilitates multisite research by allowing programming code written at one health system to be distributed and efficiently run at other health systems with minimal site-specific customization.
The analyst at the lead health system prepared the data extraction programs, which were code-reviewed by another health system’s analyst before dissemination to the remaining systems for implementation. The limited datasets were transferred back to the lead health system and reviewed for quality assurance and then combined into the final composite analytic dataset (N=86,565 patients). It included healthcare utilization data for adult patients with at least one HEDIS-qualifying AOD use disorder diagnosis. This research was reviewed and approved by the Kaiser Permanente Northern California Institutional Review Board. It met requirements for a waiver of informed consent.
Measures
HEDIS Performance Measure Outcomes: Treatment Initiation and Engagement.
Following the National Committee for Quality Assurance (NCQA) Measure Technical Specifications,29 the following data were extracted to identify all patients with an index diagnosis of AOD abuse or dependence: Diagnosis-Related Group (DRG) categories, International Classification of Diseases (ICD)-9 diagnosis codes, Current Procedural Terminology (CPT) codes, Uniform/Universal Billing form (UB) 92 Revenue codes, Centers for Medicare and Medicaid Services (CMS) 1500 site of service codes, department, and date of services.26, 27 Per HEDIS definitions, adult patients with a “new” AOD abuse or dependence index diagnosis, defined as having no AOD diagnoses in the 60 days before the index diagnosis, who were continuously enrolled in the health system 2 months prior to the index date through 44 days post the index date were included in the denominator. For each patient, the index date (date of first qualifying AOD diagnosis during the study period), type of diagnosis (alcohol, cannabis, opioid, other drugs), and setting were extracted from the EHR. Settings included inpatient, emergency department (ED), psychiatry/AOD treatment, primary care (e.g., internal medicine, family practice, primary care, OBGYN, urgent care), and other outpatient.
Initiation and engagement rates were calculated consistent with HEDIS definitions. If the index diagnosis was made at an inpatient encounter, excluding detoxification, the inpatient stay was considered initiation of treatment, consistent with the HEDIS initiation definition.29 If the index episode was an ED or outpatient claim/encounter, the patient must have had a subsequent AOD service (not including ED visits or detoxification) within 14 days of the index date to be considered “initiated.” Patients who had two or more AOD-related services within 30 days after initiating treatment were considered “engaged.”29
Patient-Level Characteristics.
Patient characteristics included demographics (age, sex, race/ethnicity), length of health system membership in the year prior to the index date (allowing for a 30-day gap), insurance type (commercial/private pay, Medicare, state subsidized, unknown), type of AOD diagnoses in the year prior to index diagnosis visit (alcohol, opioid, cannabis and other drug) and location of the initiation visit, when applicable.
Co-occurring ICD-9 medical and psychiatric conditions in the year prior to the index visit were extracted from the EHR. The 18 main categories from the Healthcare Cost and Utilization Project (HCUP) clinical classifications were included.30 Additional codes related to 21 Substance Abuse-Related Medical Conditions (SAMC) identified by a consensus of researchers with expertise in addiction medicine based on conditions related to drug and alcohol abuse in the literature were also included (see Appendix 1).16, 31-35 Indicators of any medical and psychiatric SAMCs were created based on these conditions. Patients living with HIV were identified by an ICD-9 code of 042. Charlson comorbidity index scores were calculated based on diagnosis codes made in the year prior to the index date.36
Counts of primary care, ED, and psychiatry/AOD treatment visits made in the 45 days after the index date were extracted.
Organization-Level Characteristics.
Data on organization-level characteristics were provided by site investigators based on their working knowledge of the health system and publicly available information. Variables were created to determine the following: if all clinics, at least one clinic, or no clinics within each health system had the following characteristics: 1) co-location of primary care and AOD treatment in the same building/campus; 2) AOD treatment only available external to the health system (i.e., contracted out); 3) medication treatment available in AOD specialty treatment (e.g., buprenorphine, naltrexone, acamprosate); 4) medication treatment available in primary care (e.g., buprenorphine, naltrexone, acamprosate); 5) behavioral medicine specialist co-located with primary care in same building/campus; 6) use of EHR referral system to AOD treatment.
Analysis
Frequencies of the index AOD diagnosis type and department, patient characteristics, prior year medical and psychiatric SAMC conditions, prior-year Charlson comorbidity index, organizational factors and utilization patterns within 45 days after the index episode (i.e., visits to primary care, ED, and psychiatry/AOD specialty treatment) were examined across sites and by each performance measure using Chi-square tests and ANOVA models, for categorical and continuous predictors respectively. Because patients were nested within health systems, generalized linear models (GLM), with a logit link, clustered on health system, were used to model patient factors associated with initiation and engagement. These models examined a subset of key variables including patient characteristics, SAMC medical and psychiatric conditions, and index or initiation setting. Index setting was used to model treatment initiation, and initiation setting was included in the engagement model to examine the role of treatment initiation in engagement. Based on the HEDIS definition, inpatient index encounters qualified as treatment initiation, therefore only ED and outpatient (primary care psychiatry/AOD specialty treatment, and other outpatient) index encounters were examined in the treatment initiation models. Engagement rates were examined among all those who initiated treatment, including inpatient encounters. Measures potentially associated with initiation but not engagement were not examined in this study; therefore, a two-part model to account for the propensity for initiation among those engaged32 was not used.
Using the methodology described above, associations between organizational-level characteristics and performance measures were examined. Models were run separately due to correlation between the organizational-level characteristics; all models adjusted for patient age, sex, race/ethnicity and Charlson comorbidity index score.
Results
Sample characteristics
Across the health systems, 86,565 adult patients had at least one HEDIS-qualifying AOD diagnosis during the study period. Among these patients, demographics and prevalence of prior medical and psychiatric conditions differed across health systems (all p<.001; Table 1). Overall, the majority of patients were men, aged 50-64, White, and had a high prevalence of medical conditions. Commercial/private pay was the most common insurance type. Type of index diagnosis differed, although alcohol was the most prevalent across all health systems. The majority of AOD diagnoses occurred during primary care visits, followed by ED and inpatient. Utilization of primary care, ED and psychiatry/AOD specialty treatment within 45 days post index also differed across health systems (Table 1).
Table 1.
Characteristics of Patients with an Index Alcohol or Drug Abuse/Dependence Encounter in Seven Health Systems by Site, October 1, 2014 and August 15, 2015 (n=86,565)
| Health System |
||||||||
|---|---|---|---|---|---|---|---|---|
| A | B | C | D | E | F | G | p- value |
|
| Gender, % | ||||||||
| Female | 40.8 | 37.6 | 40.8 | 36.5 | 44.6 | 41.5 | 44.2 | |
| Male | 59.2 | 62.4 | 59.2 | 63.5 | 55.4 | 58.4 | 55.8 | <.001 |
| Age, % | ||||||||
| 18-29 | 22.2 | 16.9 | 24.3 | 21.6 | 19.8 | 22.1 | 17.1 | |
| 30-49 | 31.3 | 17.9 | 29.0 | 28.1 | 27.6 | 30.8 | 37.8 | |
| 50-64 | 29.0 | 37.9 | 28.1 | 29.2 | 33.2 | 29.4 | 30.2 | |
| 65+ | 17.5 | 27.3 | 18.6 | 21.2 | 19.5 | 17.8 | 14.9 | <.001 |
| Race/ethnicity, % | ||||||||
| American Indian/Alaska Native | 1.3 | 0.7 | 1.2 | 0.7 | 2.2 | 1.5 | 8.1 | |
| Asian | 0.9 | 0.6 | 5.6 | 3.3 | 2.4 | 1.5 | 0.1 | |
| Native Hawaiian/Other Pacific Islander | 0.3 | 0.0 | 0.8 | 0.5 | 0.8 | 0.7 | 0.1 | |
| Black/African American | 4.7 | 39.3 | 12.4 | 11.1 | 4.1 | 4.5 | 2.3 | |
| Hispanic | 14.2 | 1.7 | 17.3 | 30.4 | 3.4 | 4.4 | 0.7 | |
| White | 64.4 | 50.7 | 60.5 | 50.9 | 66.9 | 83.7 | 88.3 | |
| Other/Unknown | 14.2 | 7.0 | 2.2 | 3.0 | 20.2 | 3.6 | 0.4 | <.001 |
| Substance abuse related psychiatric conditions in the year prior, % | 42.9 | 45.1 | 43.2 | 43.7 | 45.6 | 47.0 | 56.0 | <.001 |
| Substance abuse related medical conditions in the year prior, % | 58.4 | 74.4 | 66.0 | 60.6 | 61.4 | 63.7 | 66.7 | <.001 |
| Charlson Comorbidity Index, mean (SD) | 0.90 (1.72) | 1.34 (1.96) | 1.12 (1.93) | 0.91 (1.68) | 0.97 (1.77) | 1.06 (1.86) | 0.77 (1.36) | <.001 |
| Insurance Type, % | ||||||||
| Commercial/Private Pay | 65.0 | 67.5 | 61.4 | 67.0 | 64.8 | 57.7 | 0.0 | |
| Medicare | 22.7 | 32.5 | 26.8 | 23.9 | 26.9 | 15.3 | 0.0 | |
| State Subsidized | 12.3 | 0.0 | 11.9 | 9.1 | 2.7 | 27.0 | 0.0 | |
| Unknown | 0.0 | 0.0 | 0.0 | 0.0 | 5.6 | 0.0 | 100.0 | <.001 |
| Type of index diagnosis, % | ||||||||
| Alcohol | 59.8 | 53.4 | 50.8 | 51.9 | 51.5 | 52.7 | 50.5 | |
| Cannabis | 14.5 | 12.9 | 15.8 | 14.9 | 16.6 | 16.0 | 9.0 | |
| Opioids | 9.0 | 13.3 | 9.9 | 16.3 | 15.8 | 13.7 | 11.8 | |
| Other drug | 16.8 | 2.0 | 23.5 | 16.9 | 16.1 | 17.6 | 28.8 | <.001 |
| Index encounter type, % | ||||||||
| Primary care, % | 20.3 | 48.1 | 21.8 | 16.5 | 14.5 | 21.6 | 19.8 | |
| Emergency department, % | 29.3 | 16.8 | 14.9 | 50.7 | 53.9 | 31.2 | 57.2 | |
| Inpatient, % | 29.6 | 15.0 | 47.6 | 13.1 | 16.1 | 24.9 | 3.6 | |
| Psychiatry/AOD treatment, % | 9.5 | 6.6 | 9.9 | 14.2 | 7.8 | 14.3 | 9.9 | |
| Other outpatient, % | 11.4 | 13.5 | 5.8 | 5.5 | 7.7 | 8.0 | 9.4 | <.001 |
| Treatment utilization 45 days post index encounter, mean(SD) | ||||||||
| Primary care | 0.58(0.99) | 0.61(0.98) | 1.08(1.82) | 0.71(1.16) | 1.29(2.96) | 0.76(1.12) | 3.20(3.62) | <.001 |
| Emergency department | 0.03(0.27) | 0.14(0.45) | 0.31(0.83) | 0.12(0.47) | 0.23(0.80) | 0.28(0.77) | 0.07(0.34) | <.001 |
| Psychiatry/AOD treatment | 0.65(1.98) | 0.98(3.35) | 3.45(14.90) | 1.70(7.91) | 0.70(2.74) | 0.51(2.68) | 0.25(1.16) | <.001 |
Treatment initiation
Of patients identified with an index diagnosis, 27.9% (24,188/86,565; unadjusted) initiated treatment (Table 2). As index encounters in an inpatient setting (excluding detox) qualified as initiation per HEDIS definitions, treatment initiation was calculated only among patients with an index encounter in an outpatient or ED setting (n=70,079). Among these patients, 11.4% (7,995/70,079) initiated treatment. Rates ranged from 5.2% to 13.6% across health systems. More patients who initiated treatment were men, aged 30-49, and White, and fewer were Hispanic. Patients who initiated had lower average Charlson comorbidity scores and more SAMC medical and psychiatric conditions. More patients with an alcohol, opioid, or other drug index diagnosis initiated treatment, while fewer with a cannabis diagnosis initiated. Patients were more likely to initiate treatment with an index diagnosis in the ED or psychiatry/AOD specialty treatment. On average, patients who initiated treatment had greater primary care, ED, and psychiatry/AOD treatment utilization in the 45 days post the index encounter (Table 2).
Table 2.
Characteristics of Patients with an Index Alcohol or Drug Abuse/Dependence Encounter by Treatment Initiation* and Engagement**
| Initiated Treatment |
Did not Initiate Treatment |
Engaged in treatment |
Did not engage in treatment |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|
| (n=7,995) | (n=62,084) | p- value |
(n=2,782) | (n=21,406) | p-value | |||||
| n | % | n | % | n | % | n | % | |||
| Gender | ||||||||||
| Female | 3,000 | 37.5 | 24,439 | 39.4 | 1,063 | 38.2 | 8,659 | 40.5 | ||
| Male | 4,995 | 62.5 | 37,645 | 60.6 | 0.002 | 1,719 | 61.8 | 12,747 | 59.6 | 0.023 |
| Age | ||||||||||
| 18-29 | 1,902 | 23.8 | 14,466 | 23.3 | 645 | 23.2 | 3,988 | 18.6 | ||
| 30-49 | 2,744 | 34.3 | 18,885 | 30.4 | 1,086 | 39.0 | 5,084 | 23.8 | ||
| 50-64 | 2,351 | 29.4 | 17,802 | 28.7 | 814 | 29.3 | 6,690 | 31.3 | ||
| 65+ | 998 | 12.5 | 10,931 | 17.6 | <.001 | 237 | 8.5 | 5,644 | 26.4 | <.001 |
| Race/ethnicity | ||||||||||
| American Indian/Alaska Native | 98 | 1.2 | 861 | 1.4 | 35 | 1.3 | 317 | 1.5 | ||
| Asian | 257 | 3.2 | 2,246 | 3.6 | 87 | 3.1 | 719 | 3.4 | ||
| Native Hawaiian/Other Pacific Islander | 45 | 0.6 | 384 | 0.6 | 16 | 0.6 | 127 | 0.6 | ||
| Black/African American | 669 | 8.4 | 5,988 | 9.6 | 181 | 6.5 | 2,429 | 11.4 | ||
| Hispanic | 1,397 | 17.5 | 12,656 | 20.4 | 494 | 17.8 | 3,635 | 17.0 | ||
| White | 5,074 | 63.5 | 36,589 | 58.9 | 1,785 | 64.2 | 13,301 | 62.1 | ||
| Other/Unknown | 455 | 5.7 | 3,360 | 5.4 | <.001 | 184 | 6.6 | 878 | 4.1 | <.001 |
| Substance abuse related psychiatric conditions in the year prior | 4,138 | 51.8 | 25,484 | 41.1 | <.001 | 1,504 | 54.1 | 11,240 | 52.5 | 0.123 |
| Substance abuse related medical conditions in the year prior | 4,858 | 60.8 | 35,728 | 57.6 | <.001 | 1,697 | 61.0 | 16,766 | 78.3 | <.001 |
| Type of index diagnosis | ||||||||||
| Alcohol | 4,318 | 54.0 | 32,574 | 52.5 | 1,511 | 54.3 | 10,741 | 50.2 | ||
| Cannabis | 673 | 8.4 | 9,480 | 15.3 | 197 | 7.1 | 3,404 | 15.9 | ||
| Opioid | 1,331 | 16.7 | 8,510 | 13.7 | 561 | 20.2 | 2,402 | 11.2 | ||
| Other drug | 1,673 | 20.9 | 11,520 | 18.6 | <.001 | 513 | 18.4 | 4,859 | 22.7 | <.001 |
| Index encounter type | ||||||||||
| Inpatient | n/a | n/a | n/a | n/a | xx | xx | xx | xx | ||
| Primary care | 2,312 | 28.9 | 29,456 | 47.5 | xx | xx | xx | xx | ||
| Emergency department | 2,749 | 34.4 | 19,804 | 31.9 | xx | xx | xx | xx | ||
| Psychiatry/Addiction treatment | 2,400 | 30.0 | 7,644 | 12.3 | xx | xx | xx | xx | ||
| Other outpatient | 534 | 6.7 | 5,180 | 8.3 | <.001 | xx | xx | xx | xx | |
| Initiation encounter type | ||||||||||
| Inpatient | xx | xx | xx | xx | 246 | 8.8 | 7,357 | 34.4 | ||
| Primary care | xx | xx | xx | xx | 280 | 10.1 | 2,302 | 10.8 | ||
| Psychiatry/AOD treatment | xx | xx | xx | xx | 1,584 | 56.9 | 1,956 | 9.1 | ||
| Other outpatient | xx | xx | xx | xx | 218 | 7.8 | 3,164 | 14.8 | ||
| Unknown | xx | xx | xx | xx | 454 | 16.3 | 6,627 | 31.0 | <.001 | |
| mean | SD | mean | SD | p- value |
mean | SD | mean | SD | p-value | |
| Charlson comorbidity Index in year prior | 0.72 | 1.43 | 0.76 | 1.51 | 0.012 | 0.77 | 1.56 | 1.67 | 2.28 | <.001 |
| Treatment utilization 45 days post index encounter | ||||||||||
| Primary care | 1.30 | 2.21 | 0.75 | 1.46 | <.001 | 1.52 | 2.78 | 1.60 | 2.47 | 0.096 |
| Emergency department | 0.34 | 0.89 | 0.14 | 0.56 | <.001 | 0.43 | 1.06 | 0.32 | 0.81 | <.001 |
| Psychiatry/AOD treatment | 12.50 | 26.50 | 0.78 | 4.78 | <.001 | 26.06 | 35.61 | 2.28 | 9.71 | <.001 |
Initiation was estimated among patients with an index encounter in an outpatient or ED setting (i.e., not inpatient) (n=70,079)
Engagement was estimated among all patients who initiated AOD treatment, including patients with an index inpatient encounter (n=24,188)
In adjusted generalized linear models (Table 3), the same predictors emerged. Women had lower odds of initiation than men (Odds Ratio [OR]=0.81, 95% Confidence Interval [CI]=0.76-0.86); Hispanic (OR=0.85, 95% CI=0.79-0.91), Black/African American (OR=0.82, 95% CI=0.75-0.90) and Asian patients (OR=0.83, 95% CI=0.72-0.95) had lower odds of treatment initiation than white patients. Patients aged 30-49 had higher odds of initiation (OR=1.11, 95% CI=1.04, 1.19) while those 65+ had lower odds (OR=0.82, 95%CI=0.74-0.90) compared with patients aged 18-29. Both prior SAMC psychiatric (OR=1.26, 95% CI=1.18-1.35) and medical (OR=1.18, 95% CI=1.10-1.26) conditions were associated with higher odds of initiation. All index settings had higher odds of initiation compared with identification in primary care (ED: OR=1.55, 95% CI=1.45-1.66; psychiatry/AOD treatment: OR=3.58, 95% CI=3.33-3.84; other outpatient: OR=1.19, 95% CI-1.06-1.32).
Table 3.
Characteristics associated with Treatment Initiation and Engagement
| Treatment Initiation* | Treatment Engagement** | |||||||
|---|---|---|---|---|---|---|---|---|
| OR | 95% CI | p-value | OR | 95% CI | p-value | |||
| Gender | ||||||||
| Female | 0.81 | 0.76 | 0.86 | <.001 | 0.92 | 0.82 | 1.04 | 0.144 |
| Male (ref) | -- | -- | -- | -- | -- | -- | -- | -- |
| Age | ||||||||
| 18-29 (ref) | -- | -- | -- | -- | -- | -- | -- | -- |
| 30-49 | 1.11 | 1.04 | 1.19 | 0.005 | 1.26 | 1.10 | 1.43 | 0.002 |
| 50-64 | 1.07 | 1.00 | 1.15 | 0.066 | 0.99 | 0.86 | 1.13 | 0.871 |
| 65+ | 0.82 | 0.74 | 0.90 | <.001 | 0.51 | 0.43 | 0.62 | <.001 |
| Race/ethnicity | ||||||||
| American Indian/Alaska Native | 0.90 | 0.72 | 1.12 | 0.335 | 0.92 | 0.62 | 1.38 | 0.688 |
| Asian | 0.83 | 0.72 | 0.95 | 0.011 | 0.92 | 0.70 | 1.20 | 0.512 |
| Native Hawaiian/Other Pacific Islander | 0.83 | 0.60 | 1.15 | 0.247 | 0.81 | 0.45 | 1.48 | 0.482 |
| Black/African American | 0.82 | 0.75 | 0.90 | 0.001 | 0.64 | 0.53 | 0.77 | <.001 |
| Hispanic | 0.85 | 0.79 | 0.91 | <.001 | 0.90 | 0.79 | 1.02 | 0.101 |
| Other/Unknown | 0.94 | 0.84 | 1.05 | 0.255 | 0.99 | 0.81 | 1.22 | 0.952 |
| White (ref) | -- | -- | -- | -- | -- | -- | -- | -- |
| Substance abuse related psychiatric conditions in prior year | 1.26 | 1.18 | 1.35 | <.001 | 1.11 | 0.98 | 1.24 | 0.061 |
| Substance abuse related medical conditions in prior year | 1.18 | 1.10 | 1.26 | <.001 | 0.87 | 0.77 | 0.99 | 0.040 |
| Index encounter type | ||||||||
| Emergency Department | 1.55 | 1.45 | 1.66 | <.001 | xx | xx | xx | |
| Inpatient | n/a | n/a | n/a | n/a | xx | xx | xx | |
| Psychiatry/AOD treatment | 3.58 | 3.33 | 3.84 | <.001 | xx | xx | xx | |
| Other outpatient | 1.19 | 1.06 | 1.32 | 0.004 | xx | xx | xx | |
| Primary Care (ref) | -- | -- | -- | -- | ||||
| Initiation encounter type | ||||||||
| Inpatient | xx | xx | xx | 0.40 | 0.32 | 0.50 | <.001 | |
| Psychiatry/AOD treatment | xx | xx | xx | 7.02 | 5.93 | 8.31 | <.001 | |
| Other outpatient | xx | xx | xx | 0.73 | 0.59 | 0.91 | 0.008 | |
| Unknown | xx | xx | xx | 0.67 | 0.55 | 0.81 | <.001 | |
| Primary Care (ref) | -- | -- | -- | -- | -- | -- | -- | -- |
Initiation was estimated among patients with an index encounter in an outpatient or ED setting (i.e., not inpatient) (n=70,079)
Engagement was estimated among all patients who initiated AOD treatment, including patients with an index inpatient encounter (n=24,188)
Treatment Engagement
Of patients who initiated AOD treatment in any department, including patients with an index inpatient encounter, 11.5% (2,782/24,188) engaged in treatment (Table 2). Engagement rates ranged from 4.5% to 17.9%. More patients who engaged in treatment were men and White and fewer were Black/African American. Those meeting engagement criteria had lower Charlson comorbidity scores and fewer had SAMC medical conditions than those who did not engage; psychiatric conditions did not differ. Engagement was more common among patients with an index diagnosis of alcohol, opioid, or other drug, and less likely with a cannabis diagnosis. Engagement occurred more frequently among patients with initiation in psychiatry/AOD treatment, and less frequently in inpatient or other outpatient settings. On average, those who engaged in treatment had more ED and psychiatry/AOD treatment visits in the 45 days post index than others; primary care visits did not differ.
In the generalized linear models, patients aged 30-49 had higher odds of engagement (OR=1.26, 95%CI=1.10-1.43) while patients aged 65 and older had lower odds (OR=0.51, 95%CI=0.43-0.62) compared with patients aged 18-29. Blacks/African Americans (OR=0.64, 95% CI=0.53-0.77) had lower odds of treatment engagement compared with Whites. Patients who initiated in psychiatry/AOD treatment had higher odds of engagement (OR=7.02, 95%CI=5.93, 8.31), while those who initiated in an inpatient (OR=0.40, 95%CI=0.32-0.50) or other outpatient setting (OR=0.73, 95% CI=0.59-0.91) had lower odds of engagement compared with patients initiating in primary care (Table 3).
Organization-Level Characteristics
All but one health system had at least one clinic where primary care and specialty treatment were co-located. Five of seven had specialty treatment only available internally (excluding methadone). Three systems did not have AOD medications available in primary care, but all had at least one clinic where they were available in specialty treatment. Behavioral medicine specialists were available in at least one primary clinic for all health systems except one. The EHR was used as the referral system to AOD treatment for five of the seven health systems; of the remaining two systems, one had at least one clinic using EHR referrals, the other did not.
In the generalized linear models, patients in health systems with co-located primary care and specialty AOD treatment had higher odds of treatment initiation (OR=2.77, 95% CI=1.89, 4.05) and engagement (OR=3.55, 95% CI=1.50, 8.43). Patients had higher odds of engagement when specialty treatment was available internally rather than contracted out (OR=2.27, 95% CI=1.07, 4.83). Patients at health systems where at least one clinic used the EHR for referrals to specialty treatment had lower odds of initiation (OR=0.35, 95% CI=0.21, 0.58) and engagement (OR=0.17, 95% CI=0.08, 0.36) than health systems that did not; patients also had lower odds of engagement when all clinics used EHR referrals (OR=0.54, 95% CI=0.33, 0.88) (Table 4).
Table 4.
Organizational Characteristics associated with Treatment Initiation and Engagement
| Treatment Initiation* | Treatment Engagement** | |||||||
|---|---|---|---|---|---|---|---|---|
| OR | 95% CI | p- value |
OR | 95% CI | p- value |
|||
| Primary care and specialty AOD treatment co-located | ||||||||
| At least one clinic but not all | 2.77 | 1.89 | 4.05 | 0.001 | 3.55 | 1.50 | 8.43 | 0.013 |
| None (ref) | -- | -- | -- | -- | -- | -- | -- | -- |
| Specialty treatment only available internally (excluding methadone treatment) | ||||||||
| At least one clinic but not all | 1.73 | 0.94 | 3.18 | 0.070 | 2.27 | 1.07 | 4.83 | 0.038 |
| None (ref) | -- | -- | -- | -- | -- | -- | -- | -- |
| Medication assisted treatment availability in primary care | ||||||||
| All clinics | 1.44 | 0.48 | 4.38 | 0.411 | 1.33 | 0.34 | 5.25 | 0.593 |
| At least one clinic but not all | 1.20 | 0.54 | 2.65 | 0.563 | 1.78 | 0.66 | 4.78 | 0.179 |
| None (ref) | -- | -- | -- | -- | -- | -- | -- | -- |
| Medication assisted treatment availability in specialty treatment | ||||||||
| All clinics | 1.29 | 0.64 | 2.60 | 0.399 | 1.08 | 0.40 | 2.92 | 0.856 |
| At least one clinic but not all (ref) | -- | -- | -- | -- | -- | -- | -- | -- |
| Behavioral medicine specialist availability in primary care | ||||||||
| All clinics | 1.47 | 0.58 | 3.96 | 0.338 | 0.80 | 0.17 | 3.72 | 0.706 |
| At least one clinic but not all | 0.93 | 0.35 | 2.48 | 0.842 | 0.65 | 0.14 | 3.05 | 0.485 |
| None (ref) | -- | -- | -- | -- | -- | -- | -- | -- |
| EHR use for referrals to specialty AOD treatment | ||||||||
| All clinics | 0.98 | 0.68 | 1.41 | 0.880 | 0.54 | 0.33 | 0.88 | 0.025 |
| At least one clinic but not all | 0.35 | 0.21 | 0.58 | 0.005 | 0.17 | 0.08 | 0.36 | 0.003 |
| None (ref) | -- | -- | -- | -- | -- | -- | -- | -- |
Note: all models were run separately for each measure due to collinearity; models adjust for gender, age, race/ethnicity, and Charlson index
Initiation was estimated among patients with an index encounter in an outpatient or ED setting (i.e., not inpatient) (n=70,079)
Engagement was estimated among all patients who initiated AOD treatment, including patients with an index inpatient encounter (n=24,188)
Discussion
This study used HEDIS measures to investigate use of AOD treatment services in a diverse sample of seven health systems across the United States. We found that overall initiation and engagement rates were low relative to the need for AOD services. Age, race/ethnicity, co-occurring conditions and department of identification were identified as key factors associated with AOD-IET. Specifically, Black/African Americans, Hispanics and Asians were less likely to initiate treatment, as were women, patients aged 65+, and those identified in a primary care versus other health care settings. Black/African Americans and patients aged 65+ were also less likely to engage in treatment, as were those who initiated in an inpatient or other outpatient setting versus primary care. Middle aged patients age 30-49 (compared to the youngest group 18-29) had better initiation and engagement rates; patients with co-occurring conditions had better initiation rates; those who initiated in psychiatry/AOD treatment had higher engagement rates. These findings support national survey results. Replicating these findings in healthcare settings rather than in a population survey is critical as it makes the evidence of disparities in access to services more robust.
Low initiation rates among patients identified in primary care is an important finding as primary care is where most people interact with health care. Primary care could play a major role in facilitating initial AOD treatment visits; however, it often does not. Additional support and training for primary care providers, including training in motivational enhancement skills, inclusion of behavioral health staff, and strategies to improve referrals, could greatly improve treatment initiation rates.
A history of medical and/or psychiatric co-occurring conditions were related to initiation, but not engagement. These patients may feel more urgency to start treatment but not necessarily to sustain engagement. Patients who initiated treatment in specialty psychiatry/AOD departments had higher odds of engagement than those initiating in primary care. However, these rates also need improvement.
Overall, organizational characteristics were less related to initiation and engagement than expected. Co-location of primary care and AOD treatment and having AOD treatment available internally were positively related as expected but having EHR capacity for providing referrals was negatively associated with initiation and engagement. While automated referrals may be more efficient, other referral processes such as warm-handoffs may provide more successful transitions though these types of referrals may occur less frequently when clinicians have easy access to EHRs. Other organizational characteristics, such as availability of AOD medications, were not significant. Given the heterogeneity of these characteristics across clinics within health systems, this finding may be due to the fact that these variables were measured at the health systems level rather than the clinic level.
Our most important findings were the overall low initiation and engagement rates in AOD treatment among patients with relatively good treatment access in these health systems. In the first study of these measures across health maintenance organizations, preferred provider organizations, and point of service plans,37 initiation rates varied from 26% to 46% (our overall rate was 27%, also with wide variation), and engagement rates varied from 14% to 29% (our overall rate was 11.5%, ranging from 4.5% to 17.9%). Thus, rates have improved little over time, and some have even dropped.37
Recent years have seen many health policies implemented that were expected to improve treatment initiation and engagement. These include the Paul Wellstone and Pete Domenici Mental Health Parity and Addiction Equity Act (MHPAEA) of 2008,38 which required health plans to cover mental health and AOD treatment services and the Affordable HealthCare Act,23 which increased health care coverage and made AOD treatment services “essential benefits.”39 Other policy changes, such as Meaningful Use,39 which has increased the use of EHRs, should better facilitate referrals, as should the focus on integration by the Centers for Medicare and Medicaid, Institute of Medicine Reports6 and the Surgeon General’s Report.5 More recent changes in healthcare policy, including reversal of the ACA individual mandate, may also have an impact. It is important to continue measuring HEDIS-based outcomes moving forward, as we have far to go to improve AOD treatment access. Developing a deeper understanding of the patient, provider, and health system characteristics related to initiating and engaging in treatment should provide some needed answers for improvement.
This study based on EHR data from multiple health systems had several limitations common to observational studies. Many individuals possibly eligible for an AOD diagnosis may go unrecognized or undocumented; thus, our analyses did not include them. Without this omission, the true denominator would be larger and the gap even wider than this paper documents. For HEDIS measures (not specific to this study), quality and specificity of care are unknown. It is also challenging to compare inpatient settings to other settings that require more documentation. Department coding varied somewhat across health systems. Three health systems included AOD treatment within psychiatry; thus, our analyses combined them. One health system used a utilization-based enrollment definition, a conservative capture of patients using the healthcare system, but this is unlikely to impact study results. Insurance information was not available for one health system.
The study timeframe (October 1, 2014 to August 15, 2015) was selected to allow use of the most recent data before the ICD-9/ICD-10 transition. The transition to ICD-10 coding could affect performance measures; future studies should evaluate the new coding scheme to determine whether actual changes in the HEDIS measures occur rather than artificial changes.
Conclusion
Despite recent measures to increase access to treatment, this study of seven heterogeneous health systems found that initiation and engagement rates in AOD treatment remain low. Systems should focus most on those with the worst rates, specifically, women, minorities and patients aged 65+, but rates were low for all patients needing services. The biggest improvements are needed in primary care, where most AOD disorders are identified, and patients can be helped to initiate treatment. Both structural changes and motivational interventions are called for to improve rates of AOD patient initiation and engagement in treatment, and to provide a benchmark for future study outcomes.
Acknowledgements:
We wish to thank Agatha Hinman at Kaiser Permanente Northern California, and Richard Contreras at Kaiser Permanente Southern California for their contributions. This study was supported by a grant from the National Institute of Drug Abuse (NIDA) 5UG1DA040314-03. The content is solely the responsibility of the authors and does not necessarily represent the official views of NIDA. The NIDA Clinical Trials Network (CTN) Research Development Committee reviewed the study protocol and the NIDA CTN publications committee reviewed and approved the manuscript for publication. The funding organization had no role in the collection, management, analysis, and interpretation of the data or decision to submit the manuscript for publication.
Appendix 1: ICD9 Medical and Psychiatric Codes for Substance Abuse-Related Medical Conditions (SAMCs) Diagnoses
| Depression | 296.2, 296.3, 296.82, 298.0, 300.4, 301.12, 309.0, 309.1, 309.28, 311 |
| Injury and poisonings | 800-999 |
| Anxiety and nervous disorders | 300.00, 300.01, 300.02, 300.2, 300.3, 309.21, 309.24, 309.81, 308.3 |
| Hypertension | 362.11, 401, 403, 402.00, 404.10, 402.90, 404.0, 405 |
| Asthma | 493 |
| Psychoses | 295, 297, 298.1, 298.2, 298.3, 298.4, 298.8, 298.9, 296.0, 296.1, 296.4, 296.5, 296.6, 296.7, 296.80, 296.81, 296.89, 296.9 |
| Acid-related disorders | 530.1, 531, 532, 533, 535, 536.8 |
| Ischemic heart disease | 410, 411, 412, 413, 414 |
| Pneumonia | 480, 481, 482, 483, 484, 485, 486, 487 |
| Chronic obstructive pulmonary disease | 490, 491, 492, 494, 496 |
| Liver cirrhosis | 571 |
| Hepatitis C | 070.41, 070.44, 070.51, 070.54 |
| Diseases of the pancreas | 577 |
| Alcoholic gastritis | 535.3 |
| Toxic effects of alcohol (ethyl and unspecified) | 980.0, 980.9 |
| Alcohol neuropathy | 357.5 |
| Drug neuropathy | 357.6 |
| Alcoholic cardiomyopathy | 425.5 |
| Excess blood alcohol level | 790.3 |
| Poisoning by alcohol | E86.0 |
| Drug dependence in mother-childbirth | 648.3 |
References
- [1].Weisner C, Mertens J, Parthasarathy S, Moore C and Lu Y. Integrating primary medical care with addiction treatment: a randomized controlled trial. JAMA 2001;286(14):1715–1723. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [2].Stein MD. Medical consequences of substance abuse. Psychiatr Clin North Am 1999;22(2):351–370. [DOI] [PubMed] [Google Scholar]
- [3].Sikkink J and Fleming MF. Adverse health effects and medical complications of alcohol, nicotine, and drug abuse In: Fleming MF and Barry KL eds. Addictive Disorders: A Practical Guide to Treatment. St. Louis: Mosby-Year Book Primary Care Series; 1992:145–168. [Google Scholar]
- [4].National Institute on Alcohol Abuse and Alcoholism. Seventh Special Report to the U.S. Congress on Alcohol and Health. Rockville, MD: U.S. Dept. of Health and Human Services Public Health Service; DHHS Publication No. ADM 90-1656. https://babel.hathitrust.org/cgi/pt?id=pur1.32754062634468;view=1up;seq=3. Published 1990. Accessed January 12, 2018. [Google Scholar]
- [5].Moos RH, Brennan PL and Mertens JR. Diagnostic subgroups and predictors of one-year re-admission among late-middle-aged and older substance abuse patients. J Stud Alcohol 1994;55(2):173–183. [DOI] [PubMed] [Google Scholar]
- [6].Kessler RC, Nelson CB, McGonagle KA, Edlund MJ, Frank RG and Leaf PJ. The epidemiology of co-occuring addictive and mental disorders: Implications for prevention and service utilization. Am J Orthopsychiatry 1996;66(1):17–31. [DOI] [PubMed] [Google Scholar]
References
- [1].Rudd RA, Aleshire N, Zibbell JE and Gladden RM. Increases in drug and opioid overdose deaths - United States, 2000–2014. MMWR Morb Mortal Wkly Rep 2016;64(50–51):1378–1382. [DOI] [PubMed] [Google Scholar]
- [2].Center for Behavioral Health Statistics and Quality. Results from the 2015 National Survey On Drug Use And Health: Detailed tables. Rockville, MD: Substance Abuse and Mental Health Services Administration; 2016. [Google Scholar]
- [3].McGlynn EA, Asch SM, Adams J, et al. The quality of health care delivered to adults in the United States. N Engl J Med 2003;348(26):2635–2645. [DOI] [PubMed] [Google Scholar]
- [4].Clark HW, Power AK, Le Fauve CE and Lopez EI. Policy and practice implications of epidemiological surveys on co-occurring mental and substance use disorders. J Subst Abuse Treat 2008;34(1):3–13. [DOI] [PubMed] [Google Scholar]
- [5].U.S. Department of Health and Human Services and Office of the Surgeon General. Facing Addiction in America: The Surgeon General’s Report on Alcohol, Drugs, and Health. Washington, DC: U.S. Department of Health & Human Services; 2016. [PubMed] [Google Scholar]
- [6].Institute of Medicine. Improving the Quality of Health Care for Mental and Substance-Use Conditions. Washington, DC: National Academies Press; 2006. [PubMed] [Google Scholar]
- [7].Harris AH, Bowe T, Finney JW and Humphreys K. HEDIS initiation and engagement quality measures of substance use disorder care: impact of setting and health care specialty. Popul Health Manag 2009;12(4):191–196. [DOI] [PubMed] [Google Scholar]
- [8].National Committee for Quality Assurance. HEDIS® & performance measurement. http://www.ncqa.org/hedis-quality-measurement. Published 2018. Accessed June 25, 2018.
- [9].Garnick DW, Horgan CM, Acevedo A, McCorry F and Weisner C. Performance measures for substance use disorders--what research is needed? Addict Sci Clin Pract 2012;7(1):18. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [10].Selby JV, Schmittdiel JA, Lee J, et al. Meaningful variation in performance: what does variation in quality tell us about improving quality? Med Care 2010;48(2):133–139. [DOI] [PubMed] [Google Scholar]
- [11].Yarborough BJH, Chi FW, Green CA, et al. Patient and system characteristics associated with performance on the HEDIS measures of Alcohol and Other Drug Treatment Initiation and Engagement [published online March 19). J Addict Med 2018. [DOI] [PubMed] [Google Scholar]
- [12].Choi S, Adams SM, Morse SA and MacMaster S. Gender differences in treatment retention among individuals with co-occurring substance abuse and mental health disorders. Subst Use Misuse 2015;50(5):653–663. [DOI] [PubMed] [Google Scholar]
- [13].Greenfield SF, Brooks AJ, Gordon SM, et al. Substance abuse treatment entry, retention, and outcome in women: A review of the literature. Drug Alcohol Depend 2007;86(1):1–21. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [14].McKellar JD, Harris AH and Moos RH. Predictors of outcome for patients with substance-use disorders five years after treatment dropout. J Stud Alcohol 2006;67(5):685–693. [DOI] [PubMed] [Google Scholar]
- [15].Mertens J and Weisner C. Predictors of alcohol and drug treatment seeking, initiation, and retention in an HMO. Research Society on Alcoholism 24th Annual Scientific Meeting Vol. Montreal, Canada2001. [Google Scholar]
- [16].Weisner C, Mertens J, Parthasarathy S, Moore C and Lu Y. Integrating primary medical care with addiction treatment: a randomized controlled trial. JAMA 2001;286(14):1715–1723. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [17].Wells K, Klap R, Koike A and Sherbourne C. Ethnic disparities in unmet need for alcoholism, drug abuse, and mental health care. Am J Psychiatry 2001;158(12):2027–2032. [DOI] [PubMed] [Google Scholar]
- [18].Zemore SE, Murphy RD, Mulia N, et al. A moderating role for gender in racial/ethnic disparities in alcohol services utilization: Results from the 2000 to 2010 national alcohol surveys. Alcohol Clin Exp Res 2014;38(8):2286–2296. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [19].Mertens J and Weisner C. People who seek, start, and remain in treatment in an HMO: Who are they? FrontLines 2003;June:6. [Google Scholar]
- [20].Mulia N, Schmidt LA, Ye Y and Greenfield TK. Preventing disparities in alcohol screening and brief intervention: the need to move beyond primary care. Alcohol Clin Exp Res 2011;35(9):1557–1560. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [21].Mulia N, Tam TW and Schmidt LA. Disparities in the use and quality of alcohol treatment services and some proposed solutions to narrow the gap. Psychiatr Serv 2014;65(5):626–633. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [22].Mertens J, Weisner C and Sterling S. Disparities across treatment settings for the medically indigent: implications for substance abuse screening and interventions. FrontLines 2001;June:6;8. [Google Scholar]
- [23].U.S. Congress. Patient Protection and Affordable Care Act, 42 U.S.C. § 18001. Public Law 111–148. Washington, DC: U.S. Government Printing Office; https://www.gpo.gov/fdsys/pkg/PLAW-111publ148/html/PLAW-111publ148.htm. Published 2010. Accessed March 7, 2018. [Google Scholar]
- [24].Andersen R and Newman JF. Societal and individual determinants of medical care utilization in the United States. Milbank Mem Fund Q Health Soc 1973;51(1):95–124. [PubMed] [Google Scholar]
- [25].Satre DD, DeLorenze GN, Quesenberry CP, Tsai A and Weisner C. Factors associated with treatment initiation for psychiatric and substance use disorders among persons with HIV. Psychiatr Serv 2013;64(8):745–753. [DOI] [PMC free article] [PubMed] [Google Scholar]
- [26].National Committee for Quality Assurance. Summary table of measures, product lines and changes. HEDIS 2015, Volume 2 (p.8); http://www.ncqa.org/Portals/0/HEDISQM/Hedis2015/List_of_HEDIS_2015_Measures.pdf. Published 2015. Accessed July 26, 2018. [Google Scholar]
- [27].Agency for Healthcare Research and Quality. Engagement of alcohol and other drug (AOD) treatment: percentage of members who initiated treatment and who had two or more additional services with a diagnosis of AOD within 30 days of the initiation visit. National Quality Measures Clearinghouse; https://www.qualitymeasures.ahrq.gov/summaries/summary/49778. Published October 2015. Accessed June 21, 2018. [Google Scholar]
- [28].Health Care Systems Research Network. Who we are. http://www.hcsrn.org/en/ Published 2015. Accessed July 10, 2018.
- [29].National Committee for Quality Assurance. HEDIS 2015 QRS Technical Update. Washington (DC): National Committee for Quality Assurance (NCQA); http://www.ncqa.org/Portals/0/HEDISQM/Hedis2015/HEDIS%20QRS%202015%20Technical%20Update_Final.pdf. Published October 1 2014. Accessed July 26, 2018. [Google Scholar]
- [30].HCUP CCS. Healthcare Cost and Utilization Project (HCUP). Rockville,MD: Agency for Healthcare Research and Quality; https://www.hcup-us.ahrq.gov/toolssoftware/ccs/ccs.jsp#examples. Published 2017. Accessed July 17, 2018. [Google Scholar]
- [31].Stein MD. Medical consequences of substance abuse. Psychiatr Clin North Am 1999;22(2):351–370. [DOI] [PubMed] [Google Scholar]
- [32].Sikkink J and Fleming MF. Adverse health effects and medical complications of alcohol, nicotine, and drug abuse In: Fleming MF and Barry KL eds. Addictive Disorders: A Practical Guide to Treatment. St. Louis: Mosby-Year Book Primary Care Series; 1992:145–168. [Google Scholar]
- [33].National Institute on Alcohol Abuse and Alcoholism. Seventh Special Report to the U.S. Congress on Alcohol and Health. Rockville, MD: U.S. Dept. of Health and Human Services Public Health Service; DHHS Publication No. ADM 90-1656. https://babel.hathitrust.org/cgi/pt?id=pur1.32754062634468;view=1up;seq=3. Published 1990. Accessed January 12, 2018. [Google Scholar]
- [34].Moos RH, Brennan PL and Mertens JR. Diagnostic subgroups and predictors of one-year re-admission among late-middle-aged and older substance abuse patients. J Stud Alcohol 1994;55(2):173–183. [DOI] [PubMed] [Google Scholar]
- [35].Kessler RC, Nelson CB, McGonagle KA, Edlund MJ, Frank RG and Leaf PJ. The epidemiology of co-occuring addictive and mental disorders: Implications for prevention and service utilization. Am J Orthopsychiatry 1996;66(1):17–31. [DOI] [PubMed] [Google Scholar]
- [36].Charlson ME, Charlson RE, Peterson JC, Marinopoulos SS, Briggs WM and Hollenberg JP. The Charlson comorbidity index is adapted to predict costs of chronic disease in primary care patients. J Clin Epidemiol 2008;61(12):1234–1240. [DOI] [PubMed] [Google Scholar]
- [37].Garnick DW, Lee MT, Chalk M, et al. Establishing the feasibility of performance measures for alcohol and other drugs. J Subst Abuse Treat 2002;23(4):375–385. [DOI] [PubMed] [Google Scholar]
- [38].Centers for Medicare & Medicaid Services. Subtitle B—Paul Wellstone and Pete Domenici Mental Health Parity and Addiction Equity Act of 2008. H. R. 1424—117; https://www.cms.gov/Regulations-and-Guidance/Health-Insurance-Reform/HealthInsReformforConsume/downloads/MHPAEA.pdf. Published 2008. Accessed June 25, 2018. [Google Scholar]
- [39].Meaningful use. HealthIT.gov. Washington, DC: Office of the National Coordinator for Health Information Technology; http://www.healthit.gov/policy-researchers-implementers/meaningful-use. Published 2013. Accessed July 10, 2018. [Google Scholar]
