RESUMO
OBJECTIVE: To compare three antidepressant drugs from different classes used in treating moderate-to-severe major depressive disorder (MDD) in Colombian adults. METHODS: Based on expert input, a decision-tree model was adapted for Colombia to analyze data over 6 months from the government-payer perspective. The cost-effectiveness of amitriptyline, fluoxetine, and venlafaxine was determined. The clinical outcome was remission of depression (a score <7 on the Hamilton Depression [HAM-D] scale or <12 on the Montgomery-Åsberg Depression Rating Scale [MADRS]) after 8 weeks of treatment. Clinical data were obtained from the literature and costs from standard Colombian price lists. One-way and multivariate sensitivity analyses tested model robustness. RESULTS: Costs per patient (in 2007 US$) for treatment were: venlafaxine, $1 618; fluoxetine, $1 207; and amitriptyline, $1 068. Overall remission rates were 73.1 percent, 64.1 percent, and 71.3 percent, respectively. Amitriptyline dominated fluoxetine (i.e., it had lower costs and higher outcomes). The incremental cost-effectiveness ratio (ICER) of venlafaxine over amitriptyline was US$ 31 595. The acquisition price of venlafaxine was the model's cost driver, comprising 53.4 percent of the total cost/patient treated, compared with 18.5 percent and 24.8 percent for fluoxetine and amitriptyline, respectively. For the others, hospitalization comprised the major cost (72.1 percent and 65.2 percent, respectively). Probabilistic (Monte Carlo) sensitivity analysis confirmed the original findings of the pharmacoeconomic model. CONCLUSIONS: Amitriptyline is cost-effective in comparison to fluoxetine and venlafaxine in Colombia. However, the cost of venlafaxine was estimated for the brand-name product, as generics were not currently available. These cost-effectiveness results can be substantially affected by the presence of generics or drug cost regulations.
OBJETIVO: Comparar tres medicamentos antidepresivos de diferentes clases empleados para tratar trastornos depresivos mayores moderados e intensos en adultos colombianos. MÉTODOS: A partir de los aportes de expertos se adaptó un modelo de árbol de decisión para Colombia a fin de analizar los datos de seis meses desde la perspectiva del gobierno como pagador de los servicios. Se determinó la relación costo-efectividad de la amitriptilina, la fluoxetina y la venlafaxina. El desenlace clínico fue la remisión de la depresión (una puntuación <7 en la escala de depresión de Hamilton o <12 en la escala de valoración de la depresión de Montgomery-Åsberg) después de 8 semanas de tratamiento. Los datos clínicos se obtuvieron de la literatura especializada y los costos, de las listas habituales de precios de Colombia. Se realizaron análisis de sensibilidad simples y multifactoriales para probar la robustez de los modelos. RESULTADOS: Los costos del tratamiento por paciente (en dólares estadounidenses de 2007) fueron: US$ 1 618 para la venlafaxina, US$ 1 207 para la fluoxetina y US$ 1 068 para la amitriptilina. Las tasas de remisión general fueron 73,1 por ciento, 64,1 por ciento y 71,3 por ciento, respectivamente. La amitriptilina tuvo un menor costo y una mayor remisión que la fluoxetina. La razón de rentabilidad incremental de la venlafaxina sobre la amitriptilina fue de US$ 31 595. El inductor de costos (cost driver) del modelo fue el valor de adquisición de la venlafaxina, que representó 53,4 por ciento del total del costo por paciente tratado, en comparación con la fluoxetina (18,5 por ciento) y la amitriptilina (24,8 por ciento). En los otros casos, la hospitalización representó el mayor costo (72,1 por ciento y 65,2 por ciento, respectivamente). El análisis de sensibilidad probabilístico (Monte Carlo) confirmó los resultados preliminares del modelo farmacoeconómico. CONCLUSIONES: En Colombia, la amitriptilina es más efectiva en función del costo que la fluoxetina y la venlafaxina. No obstante, el costo de la venlafaxina se estimó a partir del medicamento de marca, ya que no había genéricos disponibles. Esta relación costo-efectividad puede variar considerablemente con la aparición de medicamentos genéricos o medidas regulatorias del costo de los medicamentos.
Assuntos
Humanos , Masculino , Feminino , Amitriptilina/economia , Antidepressivos/economia , Cicloexanóis/economia , Transtorno Depressivo/tratamento farmacológico , Fluoxetina/economia , Modelos Teóricos , Amitriptilina/uso terapêutico , Antidepressivos/uso terapêutico , Colômbia/epidemiologia , Convulsoterapia/economia , Análise Custo-Benefício , Cicloexanóis/uso terapêutico , Árvores de Decisões , Transtorno Depressivo/economia , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/terapia , Países em Desenvolvimento , Custos de Medicamentos , Fluoxetina/uso terapêutico , Gastos em Saúde/estatística & dados numéricos , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Método de Monte Carlo , Programas Nacionais de Saúde/economia , Visita a Consultório Médico/economia , Psicoterapia/economiaRESUMO
Background: Data from the Ministry of Health show that in Chile in 2004, 17 percent of the population had some form of depression and mood disorders are the tenth cause of disability-adjusted Ufe years (DALY) loss. Aim: To determine consumption of antidepressants (ADs) in Chile from 1992 to 2004. Material and methods: National sales data were obtained from the company IMS Health Chile and converted into defined daily doses (DDDs) per 1,000 inhabitants per day Available ADs were classified in four pharmacological groups (i.e., serotonin-norepinephrine reuptake inhibitors, SNRIs; selective-serotonin reuptake inhibitors, SSRIs; tricyclic antidepressants, TCAs; and others). Total economic burden of ADs utilization and cost per DDDs were also calculated. Trends over time were analyzed using Pearson-R2. Results: Total ADs consumption in Chile measured by DDDs per 1,000 inhabitants per day (DHD) increased linearly (y =0.901x+1.9129; R2 =0.9296; p <0.001) from 2.5 in 1992 to 11.7 in 2004 (total growth of 470.2 percent). SSRIs were the drug class with higher consumption, and fluoxetine the most commonly consumed antidepressant. SSRIs were the drugs that dominated the market representing 79 percent of the total drug consumption throughout the years. Total economic burden of ADs in Chile (total cost of DDDs consumed) increased from US$65.4 million in 2001 to US$74.6 million in 2004 (14 percent increase). Average cost per DDD of all AD increased linearly, however not significantly from US$ 0.94 in 2001 to US$ 1.04 in 2004 (y =0.0362x+0.8784; R2 =0.7382; p =0,262). Conclusions: DDDs per 1,000 inhabitants per day increased linearly over 470 percent from 1992-2004. SSRIs were the most commonly consumed drugs in Chile. Future research should evaluate the cost-effectiveness of antidepressants in Chile, comparing the results with drug utilization, and determining if unnecessary expenditures have been paid out.