Do Biologic Therapies for Rheumatoid Arthritis Offset Treatment-Related Resource Utilization and Cost? A Review of the Literature and an Instrumental Variable Analysis

Comorbidities Before and After the Diagnosis of Rheumatoid Arthritis: A Matched Longitudinal Study

OBJECTIVE

To determine the contribution of rheumatoid arthritis (RA) to conditions and medical events. A secondary objective is to quantify this association before and after the introduction of biologic medications.

METHODS

All data were collected as health administrative data in Ontario, Canada. Patients with RA (n = 136 678) matched 1:1 to a pool of possible controls without RA from 1995 to 2016. The study was a retrospective longitudinal observational administrative data-based cohort study with cases (RA) and controls (two non-RA comparator groups). The main exposure was new-onset RA identified by a validated diagnosis algorithm. The secondary exposure was the calendar year, which provided a natural experiment to compare years in which biologics were unavailable (pre-2001) to increasing utilization over time. The main outcomes were counts of 27 Johns Hopkins Expanded Diagnostic Cluster Comorbid Conditions. Outcomes were reported as counts and percentage differences between cases and matched controls.

RESULTS

Patients experienced increases in conditions and medical events up to 5 years before RA disease incidence-4.9 conditions per patient-year compared with 4.6 conditions per patient-year in matched controls. Comorbidities increased to 8.7 conditions per patient-year in the year of RA incidence but were lower in the years after diagnosis-6.9 conditions per patient-year at 5 years postdiagnosis.

CONCLUSION

This study reframes the clinical manifestations of RA with detailed data on the marginal contribution of RA to conditions and medical events. These results show that a large portion of disease burden is due to the indirect effects of RA.

Impact of Psychiatric Comorbidity on Health Care Use in Rheumatoid Arthritis: A Population-Based Study

Objective

Psychiatric comorbidity is frequent in rheumatoid arthritis (RA) and complicates treatment. The present study was undertaken to describe the impact of psychiatric comorbidity on health care use (utilization) in RA.

Methods

We accessed administrative health data (1984–2016) and identified a prevalent cohort with diagnosed RA. Cases of RA (n = 12,984) were matched for age, sex, and region of residence with 5 controls (CNT) per case (n = 64,510). Within each cohort, we identified psychiatric morbidities (depression, anxiety, bipolar disorder, and schizophrenia [PSYC]), with active PSYC defined as ≥2 visits per year. For the years 2006–2016, annual rates of ambulatory care visits (mean ± SD per person) categorized by provider (family physician [FP], rheumatologist, psychiatrist, other specialist), hospitalization (% of cohort), days of hospitalization (mean ± SD), and dispensed drug types (mean ± SD per person) were compared among 4 groups (CNT, CNT plus PSYC, RA, and RA plus PSYC) using generalized linear models adjusted for age, sex, rural versus urban residence, income quintile, and total comorbidities. Estimated rates are reported with 95% confidence intervals (95% CIs). We tested within‐person and RA‐PSYC interaction effects.

Results

Subjects with RA were mainly female (72%) and urban residents (59%), with a mean ± SD age of 54 ± 16 years. Compared to RA without PSYC, RA with PSYC had more than additive (synergistic) visits (standardized mean difference [SMD] 10.92 [95% CI 10.25, 11.58]), hospitalizations (SMD 13% [95% CI 0.11, 0.14]), and hospital days (SMD 3.63 [95% CI 3.06, 4.19]) and were dispensed 6.85 more medication types (95% CI 6.43, 7.27). Cases of RA plus PSYC had increased visits to FPs (an additional SMD 8.92 [95% CI 8.35, 9.46] visits). PSYC increased utilization in within‐person models.

Conclusion

Managing psychiatric comorbidity effectively may reduce utilization in RA.

Presence of anti-citrullinated protein antibodies and costs and disease activity in early rheumatoid arthritis - a 3-year follow-up

Objective: To analyse healthcare utilization, loss of productivity, and disease activity in relation to presence of anti-citrullinated protein antibodies (ACPAs). Method: In total, 447 ACPA-positive and 224 ACPA-negative patients from two early rheumatoid arthritis cohorts, recruited 1996-1998 (cohort 1) and 2006-2009 (cohort 2), were followed during 3 years. Data on disease activity were collected, and patients reported healthcare utilization and days lost from work. Disease activity, healthcare costs, and loss of productivity were compared between ACPA groups. Linear regression was performed, controlling for confounders. Results: Healthcare costs did not differ significantly by ACPA status (EUR 3214 for vs EUR 2174 for ACPA-positive vs ACPA-negative patients in cohort 1, ns; EUR 4150 vs EUR 3820 in cohort 2, ns). Corresponding values for loss of productivity were EUR 9148 vs EUR 7916 (ns) and EUR 5857 vs EUR 5995 (ns). Total prescription of traditional disease-modifying anti-rheumatic drugs was higher in cohort 2 than in cohort 1. Methotrexate prescription was higher in ACPA-positive patients, but biologics did not differ significantly between ACPA groups. Disease activity was significantly more improved in cohort 2, but there was no difference in achieving remission in relation to ACPA status. In cohort 1, 25% of ACPA-positive patients were in remission vs 31% of ACPA-negative (ns) and in cohort 2, 55% vs 60% (ns). Conclusions: With increasing drug treatment for both ACPA-positive and ACPA-negative patients, outcome in ACPA-positive was no more severe than in ACPA-negative patients. Healthcare costs and loss of productivity were similar in the two groups.

Longitudinal Trends in the Direct Costs and Health Care Utilization Ascribable to Inflammatory Bowel Disease in the Biologic Era: Results From a Canadian Population-Based Analysis

OBJECTIVES

The prevalence of inflammatory bowel disease (IBD) is increasing. The total direct costs of IBD have not been assessed on a population-wide level in the era of biologic therapy.

DESIGN

We identified all persons with IBD in Manitoba between 2005 and 2015, with each matched to 10 controls on age, sex, and area of residence. We enumerated all hospitalizations, outpatient visits and prescription medications including biologics, and their associated direct costs. Total and per capita annual IBD-attributable costs and health care utilization (HCU) were determined by taking the difference between the costs/HCU accrued by an IBD case and their controls. Generalized linear modeling was used to evaluate trends in direct costs and Poisson regression for trends in HCU.

RESULTS

The number of people with IBD in Manitoba increased from 6,323 to 7,603 between 2005 and 2015. The total per capita annual costs attributable to IBD rose from $3,354 in 2005 to $7,801 in 2015, primarily driven by an increase in per capita annual anti-tumor necrosis factor costs, which rose from $181 in 2005 to $5,270 in 2015. There was a significant decline in inpatient costs for CD ($99 ± 25/yr. P < 0.0001), but not for ulcerative colitis ($8 increase ±$18/yr, P = 0.63).

DISCUSSION

The direct health care costs attributable to IBD have more than doubled over the 10 years between 2005 and 2015, driven mostly by increasing expenditures on biological medications. IBD-attributable hospitalization costs have declined modestly over time for persons with CD, although no change was seen for patients with ulcerative colitis.

The offset effect of pharmaceutical innovation: A review study

It is well known that pharmaceutical innovation has improved the health and quality of life of patients. It is however sometimes forgotten that new drugs also have the potential of improving the efficiency and the sustainability of the healthcare system. The objective of this review is to shed light on the magnitude of the offset effect that drugs may have in the realm of the healthcare system and for society as a whole. A narrative literature review was carried out. This review demonstrated that a growing body of literature has tried to measure the magnitude of the offset effect associated with pharmaceutical innovation, both at the aggregate level and for different diseases. There is evidence that the aggregate use of new drugs can generate net savings to the healthcare system and to society, as they may release both healthcare and non-healthcare resources for alternative uses. A high degree of heterogeneity in the magnitude of the effect has been found across different pathologies and different types of drugs.

Orthopedic Surgery in Rheumatoid Arthritis: Results from the Spanish National Registry of Hospitalized Patients over 17 Years

OBJECTIVE

To analyze the trend of orthopedic surgery (OS) rates on patients with rheumatoid arthritis (RA).

METHODS

Retrospective observational study based on information provided by the Spanish National System of Hospital Data Surveillance. All hospitalizations of patients with RA for orthopedic surgery [total hip arthroplasty (THA), total knee arthroplasty (TKA), arthrodesis, and upper limb arthroplasty (ULA)] during 1999-2015 were analyzed. The age-adjusted rate was calculated. Generalized linear models were used for trend analysis.

RESULTS

There were 21,088 OS in patients over 20 years of age (77.9% women). OS rate adjusted by age was 754.63/100,000 RA patients/year (women 707.4, men 861.1). Neither an increasing nor a decreasing trend was noted for the total OS. However, trend and age interacted, so in the age ranges 20-40 years and 40-60 years, an annual reduction of 2.69% and 2.97%, respectively, was noted. In the age ranges over 80 years and 60-80 years, we noted an annual increase of 5.40% and 1.09%, respectively. The average age at time of OS increased 5.5 years during the period analyzed. For specific surgeries, a global annual reduction was noted in rates for arthrodesis. In THA, there was an annual reduction in patients under 80 years. In TKA and ULA, there was an annual reduction in patients under 60 years.

CONCLUSION

Although the overall OS rate has not changed, there is a decrease in the rate of arthrodesis at all ages, THA in patients under 80 years of age, as well as TKA and ULA in patients under 60 years of age.

Trends in hip fracture in patients with rheumatoid arthritis: results from the Spanish National Inpatient Registry over a 17-year period (1999-2015). TREND-AR study

Purpose

To analyse trends in hip fracture (HF) rates in patients with rheumatoid arthritis (RA) over an extended time period (17 years).

Methods

This observational retrospective survey was performed by reviewing data from the National Surveillance System for Hospital Data, which includes more than 98% of Spanish hospitals. All hospitalisations of patients with RA and HF that were reported from 1999 to 2015 were analysed. Codes were selected using the Ninth International Classification of Diseases, Clinical Modification: ICD-9-CM: RA 714.0 to 714.9 and HF 820.0 to 820.3. The crude and age-adjusted incidence rate of HF was calculated by age and sex strata over the last 17 years. General lineal models were used to analyse trends.

Results

Between 1999 and 2015, 6656 HFs occurred in patients with RA of all ages (84.25% women, mean age 77.5 and 15.75% men, mean age 76.37). The age-adjusted osteoporotic HF rate was 221.85/100 000 RA persons/ year (women 227.97; men 179.06). The HF incidence rate increased yearly by 3.1% (95% CI 2.1 to 4.0) during the 1999–2015 period (p<0.001) and was more pronounced in men (3.5% (95% CI 2.1 to 4.9)) than in women (3.1% (95% CI 2.3 to 4.1)). The female to male ratio decreased from 1.54 in 1999 to 1.14 in 2015. The average length of hospital stays (ALHS) decreased (p<0.001) from 16.76 days (SD 15.3) in 1999 to 10.78 days (SD 7.72) in 2015. Age at the time of hospitalisation increased (p<0.001) from 75.3 years (SD 9.33) in 1999 to 79.92 years (SD 9.47) in 2015. There was a total of 326 (4.9%) deaths during admission, 247 (4.4%) in women and 79 (7.5%) in men (p<0.001).

Conclusion

In Spain, despite the advances that have taken place in controlling disease activity and in treating osteoporosis, the incidence rate of HF increased in both male and female patients with RA.

Temporal trends and regional disparity in rheumatoid arthritis and gout hospitalizations in Sweden, 1998-2015

Hospitalization is an important component of rheumatoid arthritis (RA) and gout economic burden. This study aimed to assess temporal trends and regional disparities in RA and gout hospitalizations among people aged ≥ 20 years in Sweden during 1998–2015. Data on hospital admissions with a principal diagnosis of RA or gout were collected from the National Patient Register. Age-standardized hospitalization rates (ASHRs) were calculated by means of direct standardization. The absolute and relative regional disparities were assessed. The temporal trends in ASHR and proportion of RA and gout hospitalizations from all and musculoskeletal disorders hospitalizations were analyzed using joinpoint regression. Between 1998–2000 and 2013–2015, the ASHR for RA declined by 78.9% from 109.9 to 23.2 per 100,000 Swedish adults, while it almost doubled for gout (from 10.5 to 20.8 per 100,000 Swedish adults). While in 1998–2000, RA hospitalizations were 10.3 times more frequent than gout (0.54 vs 0.05% of all hospitalizations), this ratio declined to 1.1 in 2013–2015 (0.13 vs 0.11% of all hospitalizations). The joinpoint regression revealed that, on average, the ASHR for RA declined by 10.2% (95% CI: 9.3–11.1) per year whereas for gout, it rose by 4.3% (3.2–5.4) per year during 1998–2015. While the relative regional disparities were stable, the absolute regional disparity declined for RA and increased for gout over the study period. While substantial decline in RA hospitalization is encouraging, the substantial rise in gout hospitalization is of concern, reflecting potential increase in prevalence of gout and suboptimal management of the disease.