The 36th Annual Meeting of the Society for Medical Decision Making

October 18 - 22, 2014

Purpose: As lower income countries like India experience rapid economic development, resources available for health interventions increase. Cost-effectiveness analysis (CEA) is critical for leveraging these newly acquired resources most efficiently. When interventions differentially extend life expectancy, CEA best practices require accounting for background medical spending that varies by age and sex. This practice is common in the US and Europe but less so for developing countries where data on background medical spending are sparse. We developed an approach to estimate time-varying age- and sex-specific medical spending from household consumption expenditure surveys and applied them to a policy-relevant example in India.

Method: We analyzed nationally representative household expenditure data (871,702 households) collected in 15 cross-sectional waves (1995 to 2010) by India’s National Sample Survey Organization. The main outcome was real household medical expenditure. We quantified the average expenditure attributable to household members by age and sex for the overall population and for urban and rural subpopulations for each wave using regression analysis to decompose household expenditure. We characterized time-trends with inverse-variance-weighted, local polynomial smoothing. We inflation adjusted expenditures to 2012 Rupees and accounted for complex survey sampling designs to achieve nationally representative estimates.

Result: Real per-capita average monthly medical expenditure rose nearly 60% (from 50 to 80 Rupees) between 1995 and 2010, with urban expenditure rising faster and higher than rural expenditure. Expenditure on drugs in outpatient settings accounted for 78% of total medical expenditure, lower in urban areas (74%) than in rural areas (79%). Monthly expenditure for males aged 0-19 years averaged 10 Rupees from 2005-2010 and increased with age to 225 Rupees for males aged 60+. For females aged 0-19 years during this period, expenditure averaged 8 Rupees, rose rapidly during childbearing years (150 Rupees), and were lower than men for those aged 60+ (200 Rupees). The largest growth in spending over 1995-2010 has been for urban men aged 50+ and women aged 30-59, particularly in urban areas.

Conclusion: In India, higher medical expenditure has become increasingly concentrated in urban areas particularly in older males and for outpatient drug purchases. More generally, the methods we used demonstrate that it is possible to estimate individual-level background medical expenditure from household consumption expenditure surveys for many developing countries for the purpose of conducting best-practice CEAs.

Purpose:

Neisseria meningitidis (NM) is a leading cause of bacterial meningitis and septicemia in infants, young children and adolescents, with considerable morbidity and mortality and outbreaks every two years in certain parts of the world. Public health costs associated with meningococcal outbreaks are not well known in Latin America. The aim of the study is to provide estimates of the economic burden of meningococcal outbreaks in two endemic countries of the region. 

Methods:

We developed an economic model to estimate the cost associated with meningococcal outbreaks in Brazil (Campinas, Sao Paulo) and Colombia (Cartagena and Sincelejo, Cartagena de Indias) from a societal perspective. Structured interviews were conducted by local health authorities to estimate the cost of the outbreaks. The interviews captured information about the use of resources, expenses allocated to case management (e.g. chemoprophylaxis), immunization campaigns and response activities during the outbreak and disease surveillance after the outbreak. Resource utilization and cost data associated with control of the outbreak (response phase) and monitoring of disease (disease surveillance phase) were collected retrospectively. 

Results:

Costs associated with outbreaks of meningococcal disease were reported from two recent outbreaks: one in Brazil (Vila Brandina in 2011), and one in Colombia (Cartagena de Indias in 2012). The first outbreak that occurred in Vila Brandina, São Paulo, reported 3 cases that were associated with a total investigation and outbreak management cost of US$34,425 (US$11,475 per notified case), compared to US$735.10 (US$122.52 per notified case) for the 2012 outbreak, which reported 6 cases in Cartagena de Indias. These costs correspond to the disease response phase. For the disease surveillance phase, the costs ranged from US$3,935 (Cartagena outbreak) to US$6,667 (outbreak in Vila Brandina). The difference in cost between the two outbreaks was due to the number of cases of an outbreak, the size of the population, the area of exposure, and management practices.

Conclusions:

Findings of this study underscore the importance of meningococcal disease in the region. Current study findings will be used to inform national health authorities about the economic burden of meningococcal outbreaks in endemic countries of the region.

Purpose:

We aimed to estimate cost-effectiveness of a community-pharmacy service to improve adherence to new medicines for long-term-conditions, compared with current practice, by combining effectiveness in adherence improvement and intervention costs from an RCT with modelled effects of adherence on patient outcomes and healthcare costs, to estimate the effect on costs and quality-adjusted-life-years (QALYs).

Method:

The New Medicine Service (NMS) is offered by community-pharmacists in England to people starting a new medicine for asthma/ chronic obstructive pulmonary disease (COPD), type 2 diabetes (T2D), hypertension or antiplatelet/anticoagulant treatment to help improve medicines adherence. We conducted a robust, pragmatic patient-level RCT, the primary outcome was adherence at 10 weeks (defined as Morisky Medication Adherence Score, MMAS-8 ≥ 6). We undertook the economic analysis from the perspective of NHS England with a lifetime time-horizon.

We developed Markov models for each therapeutic area, using the most commonly prescribed drug in each to inform model design. Clinical event probability, treatment pathway, resource-use and costs were extracted from literature and English costing tariffs. Lifetime cost and QALYs were derived from each medicine-specific model, for adherent and non-adherent patients. A composite probabilistic model combined patient-level adherence models with adherence rates and intervention costs from the trial. Cost per extra QALY and cost-effectiveness acceptability curves were generated.

Result:

504 patients (253 current practice; 251 NMS intervention) were recruited from 46 pharmacies. 249 (49.4%) had hypertension, 117 (23.2%) asthma/COPD; 95 (18.8%) T2D; 43 (8.5%) antiplatelet/anticoagulant treatment. At Week 10 there was a significant adherence improvement in NMS arm, compared to current practice, with adjusted odds ratio 1.81 (95%CI: 1.07-3.05, p=0.03).

Mean (median, range) NHS cost at 10 weeks for patients in current practice and NMS are £260 (121, 0-1668), and £215 (110,0-1458), respectively, suggesting NMS service costs were countered by reduced NHS contact costs.

NMS generated a mean of 0.06 (95%CI: 0.00-0.16) more QALYs per patient, at a mean reduced cost of £-190 (-929-87). The NMS service dominates current practice, with an ICER (95% credibility range) of -£3,005 (-17,212-4,542). Probabilistic analysis suggests the probability that NMS dominates current practice is 0.81. NMS has a high probability (0.97) of cost-effectiveness at a willingness-to-pay of £20,000/QALY.

Conclusion:

NMS increased health gain at a cost per QALY well below most accepted UK thresholds for technology implementation, £20,000-£30,000.

Purpose:   Whiplash injury following a traffic collision may lead to whiplash-associated disorder (WAD). The present study gives a detailed description of the health care utilization among patients with whiplash injury.  It evaluates the association between patients’ expected recovery at baseline and their health care costs one year after the accident. 

Method: We re-analyzed data from a previously conducted randomized clinical trial containing one year healthcare costs of 340 patients with whiplash injury following a motor vehicle accident. Detailed descriptive statistics were generated for health care utilization and cost. A two-part Zero Adjusted Gamma (ZAGA) regression model was used to investigate the association between cost and expected recovery, adjusting for important confounders. This model was selected primarily because it addressed issues with the cost data such as high skewness and presence of zeros. Model fitting was assessed with the use of diagnostics, while Bootstrap resampling was employed for model validation.

Result: The median cost of those who expected to “never get better” (N=74) was $7,354.  This cost was three times larger that those who expected to “get better slowly” (N=101) and more than five times larger than those who expected to “get better soon” (N=165). The association between expected recovery and cost was demonstrated by the covariate adjusted two-part model, where patients expecting to “never get better” had on average 2.66 times higher costs than those who expected to “get better soon” (p-value < 0.0001). Additional covariates with significant association with cost were Whiplash Disability Questionnaire (WDQ) score (p-value < 0.0001), Center for Epidemiologic Studies Depression score (CESD) (p-value = 0.0022) and Physical Component score (PCS) (p-value < 0.0001). The model was validated and seemed to fit the data well.

Conclusion: The ZAGA model was shown to perform well for the analysis of health care cost data. Expected recovery and other modifiable factors were found to have a significant effect on health care utilization and cost. These findings could have a significant impact on policy making by informing evidence-based guidelines for managing minor traffic injuries in Ontario.